Table 1 Abbreviations

Afzal MR, Daoud EG, Cunnane R, et al. (2018)

Techniques for successful early retrieval of the Micra transcatheter pacing system: A worldwide experience.

Heart Rhythm 15(6): 841–846

n=40 (29 with full procedural details)
Follow-up duration for delayed retrievals: median 46 days (range 1 to 95 days)

Early retrieval of LP is feasible and safe. All retrievals (immediate and delayed) were successful with no serious complications. Most common reasons were elevated pacing thresholds and infections.

Only successful retrievals were included; limited generalisability due to small sample size, retrospective nature, and absence of a comparator group.

Alhuarrat M, Kharawala A, Renjithlal S, et al. (2023)

Comparison of in-hospital outcomes and complications of leadless pacemaker and traditional transvenous pacemaker implantation.

EP Europace 2023; euad269.

n=35,430 admissions; LP group: n=7780; TVP group: n=27,650; in-hospital outcomes only

LP population had significantly higher in-hospital mortality (aOR 1.6), vascular complications (aOR 7.5), venous thromboembolism (aOR 3.7), cardiac complications (aOR 1.8), device thrombus (aOR 5.0), and transfusion need (aOR 1.5) compared to TVP population. TVP population was more likely to experience pulmonary complications (aOR 0.7) and device revisions (aOR 0.4). Differences may reflect higher comorbidity burden in LP group.

Covered in systematic reviews included in evidence summary.

Ando K, Inoue K, Harada T, et al. (2023)

Safety and Performance of the Micra VR Leadless Pacemaker in a Japanese Cohort – Comparison with Global Studies

Circulation Journal 87(12): 1809–1816

n=300

Follow-up: mean 7.23; SD 2.83 months

Micra VR implantation was highly successful with a low acute (30 day) major complication rate of 3%, consistent with global trial data. No procedure- or device-related deaths occurred. Frailty scores improved post-implantation.

Limited to a non-randomised observational study with a relatively short follow-up period. More robust evidence from randomised controlled trials or meta-analyses was prioritised for the main summary.

Arps K, Li B, Allen JC Jr, et al. (2023)

Association of leadless pacing with ventricular and valvular function.

J Cardiovasc Electrophysiol 34(11):2233–2242.

n=54; median follow-up echocardiogram at 8.9 months (IQR 4.5 to 14.5)

LP implantation was not associated with worsening tricuspid regurgitation in the short term. There was a significant decline in LVEF (mean decrease: 52% to 48%, p=0.0019) and TAPSE (1.8 cm to 1.6 cm, p=0.0437), indicating a reduction in biventricular function. 24% of people experienced a 10% or more drop in LVEF, consistent with known effects of RV pacing.

Small, single-center cohort with short-term follow-up; observational nature limits ability to determine causality for observed ventricular function decline.

Bahbah A, Sengupta J, Kapphahn‐Bergs M, et al. (2024)

A comparison of procedure-related adverse events between two right ventricular leadless pacemakers.

Journal of Cardiovascular Electrophysiology 35(12): 2397–2401

n=10,940 (Micra VR), n=5,990 (AVEIR VR)

Follow-up duration not specified; adverse events reviewed from 2022 to 2024

Micra VR and AVEIR VR showed similar rates of major adverse clinical events (p=0.387) and procedure-related complications (including death and perforation). However, AVEIR VR had a higher rate of device dislodgement (p<0.001), while Micra VR had more unacceptable pacing thresholds requiring replacement (p=0.001). Design-related differences may account for these outcomes.

The study is based on retrospective analysis of adverse event reports from the MAUDE database, which may be subject to reporting biases and lacks the controlled conditions of prospective clinical trials. Therefore, more robust, randomised controlled studies were prioritised in the main evidence summary.

Bahbah A, Sengupta J, Witt D, et al. (2024)

Device dislodgement and embolization associated with a new leadless pacemaker.

Journal of Cardiovascular Electrophysiology 35(12): 2483–2486

n=5,990 (AVEIR VR, over 21 months)
n=72,237 (Micra VR, over 8 years)

Follow-up: Device approval periods: AVEIR VR (Apr 2022 to Dec 2023), Micra VR (2016 to Apr 2024)

Dislodgement and/or embolisation (D/E) occurred in less than 1% of both AVEIR VR cases and Micra VR cases (p<0001). Most AVEIR D/E events (60%) occurred during implantation, commonly due to release mechanism or fixation issues.

Data based on passive post-market surveillance (MAUDE), with known limitations in voluntary reporting accuracy and absence of clinical adjudication or comparator control.

Beccarino NJ, Choi EY, Liu B, et al. (2023)

Concomitant leadless pacing in pacemaker-dependent patients undergoing transvenous lead extraction for active infection: Mid-term follow-up.

Heart Rhythm 20(6): 853–860.

n=86, undergoing LP implantation at the time of transvenous lead extraction for active CIED infection; median follow-up 163 days (IQR 57 to 403)

Concomitant LP implantation during TLE for active infection was associated with no procedural complications and no recurrent infections during follow-up. Despite a 29% mortality rate, most deaths were unrelated to infection.

Covered by systematic reviews included in main evidence summary.

Bertelli M, Toniolo S, Ziacchi M, et al. (2022)

Is Less Always More? A Prospective Two-Centre Study Addressing Clinical Outcomes in Leadless versus Transvenous Single-Chamber Pacemaker Recipients.

J Clin Med 11(20): 6071.

n=344 (LP: n=72; TVP: n=272); follow-up duration not explicitly stated but included both acute and long-term complications

No statistically significant difference in complication rates between LP and TVP groups. Higher mortality in the TVP group attributed to older age and comorbidities. LP implantation was preferentially used in people with higher bleeding/infection risk, difficult venous access, or active lifestyle.

Covered by systematic review included in the main evidence summary.

Bhatia NK, Kiani S, Merchant FM, et al. (2021)

Life cycle management of Micra transcatheter pacing system: Data from a high-volume center.

Journal of Cardiovascular Electrophysiology 32(2): 484–490

n=302

Follow-up: mean 1105.5; SD 529.3 days (3 years)

LP was durable with low complication rates over long-term follow-up. 6% of people required system modification—either extraction (n=11) or abandonment (n=12)—mainly due to CRT upgrade, threshold issues, or battery depletion. All extractions and abandonments were successful without long-term complications.

Study focuses on long-term device management rather than long-term safety and efficacy outcomes and includes a limited number of extraction/abandonment cases.

Bodin A, Clementy N, Bisson A, et al. (2022)

Leadless or Conventional Transvenous Ventricular Permanent Pacemakers: A Nationwide Matched Control Study.

J Am Heart Assoc 11(16): e025339.

n=42,315 total (LP: 1487; TVP: 40,828); matched cohort: n=1344 per group; mean follow-up 6.2; SD 8.7 months

LP recipients had lower all-cause and cardiovascular mortality within 30 days post-implantation compared to TVP recipients. During midterm follow-up, there were no significant differences between LP and TVP groups in all-cause mortality, cardiovascular death, or infective endocarditis after matching for baseline comorbidities.

Covered by systematic review included in the main evidence summary.

Bongiorni MG, Della Tommasina V, Barletta V et al. (2019)

Feasibility and long-term effectiveness of a non-apical Micra pacemaker implantation in a referral centre for lead extraction. EP Europace 21(1): 114–120.

n=52

Follow-up: mean 13; SD 9 months

LP implantation was successful in 52 people, with 60% receiving non-apical implants. Non-apical placement was feasible and had no adverse impact on electrical performance. Pacing thresholds remained optimal in 94% of people. No device-related adverse events occurred during follow-up, demonstrating safety and long-term stability even in high-risk population.

Relatively small sample size and single-centre design More comprehensive, multicentre studies with larger cohorts and randomised controlled designs were prioritised in the main evidence summary.

Breeman KTN, Oosterwerff EFJ, de Graaf MA, et al. (2023)

Five-year safety and efficacy of leadless pacemakers in a Dutch cohort.

Heart Rhythm 20(8): 1128–1135

n=179 (93 Nanostim, 86 Micra VR)
Follow-up: mean 44; SD 26 months (3.7 years); up to 5 years

LPs demonstrated good long-term safety and performance. The 5-year major complication rate was 4% when excluding Nanostim advisory-related events, and 27% when including them. Capture threshold was less or equal to 2 V and stable in 98% of people. No infections or late complications occurred.

Includes people implanted with the discontinued Nanostim device; results may not reflect outcomes relevant to currently used LPs.

Cantillon DJ, Exner DV, Badie N, et al. (2017)

Complications and Health Care Costs Associated with Transvenous Cardiac Pacemakers in a Nationwide Assessment.

JACC: Clinical Electrophysiology 3(11): 1296–1305.

n = 72,701 (mean age 75; SD 12 years; 55% men)

Follow-up: Mean 1.5; SD 1.1 years; outcomes tracked up to 3 years

TVP complications were more frequent than previously reported, with an overall 3-year complication rate of 15 to 16%. Key findings include:

Acute complications (within 30 days): 8% in single-chamber TVP, 9% in dual-chamber TVP

Most common: thoracic trauma (4%, cost: $70,114), lead revision (4%, cost: $9,296), and infection (1%, cost: $80,247)

Long-term complications (1 to 36 months): 6% (single-chamber) and 6% (dual-chamber)

Focused on health systems and healthcare costs.

Cantillon DJ, Dukkipati SR, Ip JH, et al. (2018)

Comparative study of acute and mid-term complications with leadless and transvenous cardiac pacemakers.

Heart Rhythm 15(7): 1023–1030.

n=718 LP (LEADLESS II) vs. n=1436 TVP (matched); complications assessed at less than or at 1 month (short-term) and between 1 to 18 months (mid-term).

LP recipients had significantly fewer overall complications (HR 0.4; 95% CI 0.3 to 0.6), with reduced short-term (6% vs 9%) and mid-term (1% versus 5%) complications. LCPs had higher rates of pericardial effusion (2% versus 0.3%; p=.005) but fewer infectious, lead-related, and pocket-related events. No thoracic trauma events occurred in the LP group.

Covered in systematic review included in the main evidence summary.

Chinitz L, Ritter P, Khelae SK, et al. (2018)

Accelerometer-based atrioventricular synchronous pacing with a ventricular leadless pacemaker: Results from the Micra atrioventricular feasibility studies.

Heart Rhythm 15(9): 1363–1371.

n=64 across 12 centers in 9 countries; median 6 months post-implant (range 0 to 41.4 months); evaluation over 30 minutes of pacing.

Accelerometer-based atrial sensing algorithm achieved high atrioventricular synchrony (AVS) during pacing: 87% average AVS overall, 80% in high-degree AV block, and 94% in intrinsic conduction. AVS was significantly better during AV algorithm pacing than VVI pacing in high-degree block (p<.001).

Covered in systematic review included in the main evidence summary.

Chinitz LA, El-Chami MF, Sagi V, et al. (2023)

Ambulatory atrioventricular synchronous pacing over time using a leadless ventricular pacemaker: Primary results from the AccelAV study.

Heart Rhythm 20(1): 46–54.

n=152 enrolled; primary analysis subset: n=54 with complete AV block and normal sinus function; follow-up at 1 and 3 months

In people with complete AV block and normal sinus function, LP achieved mean resting AVS of 85% and ambulatory AVS of 75% at 1 month. Optimisation improved ambulatory AVS to 83% (p<.001). AVS remained stable at 3 months, and quality of life improved significantly (p=.031). No device upgrades were needed during the follow-up.

Covered by systematic review included in the main body evidence summary.

Crossley GH, Piccini JP, Longacre C, et al. (2023)

Leadless versus transvenous single-chamber ventricular pacemakers: 3 year follow-up of the Micra CED study.

J Cardiovasc Electrophysiol 34(4): 1015–1023.

n=6,219 (LP n=2,202; TVP n=4,017); 3-year follow-up

LP recipients had lower adjusted 3-year risks of chronic complications (HR 0.8, 95% CI 0.7 to 0.9; p<.001), device-related reintervention (HR 0.5, 95% CI 0.4 to 0.7; p<.001), and device-related infection (HR 0.4, 95% CI 0.2 to 0.8; p=.005) compared with TVP recipients. No significant difference in 3-year all-cause mortality was observed (HR 1, 95% CI 0.9 to 1.1; p=.73).

Covered by systematic review included in the main evidence summary.

Crossley GH, Longacre C, Higuera L, et al. (2024)

Outcomes of patients implanted with an atrioventricular synchronous leadless ventricular pacemaker in the Medicare population.

Heart Rhythm 21(1): 66–73.

n=7471 LP recipients; n=107,800 dual-chamber TVP recipients; outcomes assessed at 30 days and 6 months

LP recipients had higher comorbidity burden (mean Charlson Index 4.9 versus 3.8) but similar unadjusted 30-day complication rates (9% vs 9%). After adjustment, LP was associated with significantly lower 30-day (9% versus 11%) and 6-month complication rates (HR 0.5; 95% CI 0.4 to 0.6) and reinterventions (HR 0.5; 95% CI 0.4 to 0.6). Higher mortality in LP group attributed to baseline health differences.

Covered by Mhasseb (2025) systematic review included in the main evidence summary.

Darlington D, Brown P, Carvalho V, et al. (2022)

Efficacy and safety of leadless pacemaker: A systematic review, pooled analysis and meta-analysis.

Indian Pacing and Electrophysiology Journal 22(2): 77–86

18 studies included

n=2,496 (LP recipients)

Follow-up duration varied across studies

LPs demonstrated high implant success rates (96 to 100%) with low adverse event rates. Device/procedure-related death rate was less than 1%; overall complication rate 3%; pericardial tamponade 1%. Other complications such as pericardial effusion, dislodgement, revision, malfunction, infection, and access site complications occurred in less than 1% of people.

No significant differences found between LPs and TVPs for:

More updated and comprehensive studies have been included in the main evidence summary.

Defaye P, Klug D, Anselme F, et al. (2018)

Recommendations for the implantation of leadless pacemakers from the French Working Group on Cardiac Pacing and Electrophysiology of the French Society of Cardiology.

Archives of Cardiovascular Disease 111(1): 53–58.

Not applicable (guideline document); consensus formed based on expert experience and early clinical trials.

Recommended cautious use of LPs due to limited long-term data and complication risk. Identified groups most suitable for LP: those with no venous access, high infection risk, prior endocarditis, or cosmetic preferences. Advocated for implantations only in high-expertise centers with cardiac surgery facilities. Advised that only board-certified electrophysiologists with sufficient volume (more than 20 LPs/year) perform these procedures. Highlighted risks: tamponade, vascular injury, device migration, and lack of extraction experience. Stressed mandatory surveillance via national registry and outlined minimum training and implantation volumes to ensure safety.

Not an empirical study; guideline based on expert consensus rather than original research data.

Denman RA, Lee G, Phan K, et al. (2018)

Leadless Permanent Pacing: A Single Centre Australian Experience.

Heart, Lung and Circulation 28(11): 1677–1682

n=79
Follow-up: median 355 days (range; 9 to 905 days)

Implantation was successful in 96% of people. Electrical performance remained excellent over follow-up with a median R-wave of 11.2 mV, capture threshold of 0.5 V at 0.2 ms, and impedance of 754 ohm. No people required revision or were readmitted for device-related complications. 1 case of acute dislodgement was successfully managed. 5 deaths (7%) occurred, all unrelated to the device.

Single-centre study with small sample size and limited generalisability; lacks comparator arm or stratification across different risk groups.

Doshi RN, Ip JE, Defaye P, et al. (2024)

Chronic wireless communication between dual-chamber leadless pacemaker devices.

Heart Rhythm, published online ahead of print on October 19, 2024.

n=399
Follow-up: at implant, discharge, 1, 3, and 6 months

Aveir DR dual-chamber LPs demonstrated more than 90% success in implant-to-implant (i2i) wireless communication (A-to-V and V-to-A) throughout 6 months. People with less than 70% success at implant showed marked improvement by 1 month, decreasing to only 5% by 6 months. Improvements were linked to reprogramming and post-implant device adaptation.

The study focuses on device communication metrics rather than clinical outcomes such as complications, mortality, or pacing efficacy; thus, it is not directly comparable with safety and performance endpoints in the main summary.

Duray GZ, Ritter P, El-Chami M, et al. (2017)

Long-term performance of a transcatheter pacing system: 12-Month results from the Micra Transcatheter Pacing Study.

Heart Rhythm 14(5): 702–709

n=726 (Micra)
Follow-up: 12 months for safety, 24 months for electrical performance

At 12 months, freedom from major complications was 96% (95% CI: 92 to 97; p<0.0001), meeting the prespecified performance goal. The risk of major complications was 48% lower than with TVPs (HR 0.5; 95% CI: 0.6 to 0.8; p=0.001). Device performance remained stable through 24 months with projected battery life of 12.1 years.

Earlier results already incorporated into broader summaries; this study includes historical comparator data and device-specific outcomes rather than direct head-to-head comparison within a randomised framework.

El-Chami MF, Soejima K, Piccini JP et al. (2019)

Incidence and outcomes of systemic infections in patients with leadless pacemakers: Data from the Micra IDE study. Pacing and Clinical Electrophysiology 42(8): 1105–1110.

n=720 (Micra)
n=16 developed 21 serious infectious events (SIEs)
Follow-up after SIE: mean 13.1; SD 9.1 months

Serious infections (bacteraemia or endocarditis) occurred in 2% of people (16/720), on average 4.8 months post-implant. All events were adjudicated as unrelated to the device or procedure. Most infections involved gram-positive organisms and resolved with antibiotics, with no persistent bacteraemia observed.

Focused specifically on rare post-implant infectious events; small number of cases limits generalisability and does not evaluate broader safety or efficacy outcomes of the device.

El-Chami MF, Johansen JB, Zaidi A, et al. (2019)

Leadless pacemaker implant in patients with pre-existing infections: Results from the Micra postapproval registry.

J Cardiovasc Electrophysiol 30(4): 569–574.

n=105 people with prior CIED infection who underwent Micra implant attempt less than or at 30 days after device explant; mean follow-up 8.5; SD 7.1 months

LP was successfully implanted in 99% of people with recent CIED infection. No LP removals due to infection were reported. Most people received IV antibiotics pre-implant (91%) and/or post-implant (42%). 2 persons died from sepsis, but no reinfections involved the LP system.

Covered by systematic review included in the main evidence summary.

El-Chami MF, Bonner M, Holbrook R, et al. (2020)

Leadless pacemakers reduce risk of device-related infection: Review of the potential mechanisms.

Heart Rhythm 17(8): 1393–1397.

More than 3000 (across clinical trials referenced); follow-up durations vary across studies included

LPs demonstrate a markedly lower rate of infection compared to TVPs (0.00% versus 1 to 2% in trials with over 3000 people). Proposed mechanisms include absence of subcutaneous pocket and leads, minimal skin/glove contact during implantation, smaller size, implantation in a lower-flow cardiac environment, and biocompatible materials.

Narrative review — not a primary study or systematic review/meta-analysis; mechanism-focused without formal comparative data analysis.

El-Chami MF, Garweg C, Iacopino S et al. (2022)

Leadless pacemaker implant, anticoagulation status, and outcomes: Results from the Micra Transcatheter Pacing System Post-Approval Registry. Heart Rhythm 19(2): 228–234.

n=1,795 (with documented anticoagulation status)
Follow-up: 30 days post-implant

implantation was safe across all perioperative anticoagulation (AC) strategies: non-AC (n=585), interrupted AC (n=795), and continued AC (n=415). Major complication rates were 3%, 3%, and 2% respectively. Implant success exceeded 99% in all groups. Vascular or pericardial effusion events did not significantly differ among AC strategies, suggesting continued AC does not increase procedural risk.

Focused specifically on procedural safety relative to anticoagulation management, rather than overall clinical outcomes or long-term device performance.

El-Chami MF, Clementy N, Garweg C et al. (2019)

Leadless pacemaker implantation in hemodialysis patients: Experience with the Micra transcatheter pacemaker. JACC: Clinical Electrophysiology 5(2): 162–170.

n=201, on hemodialysis (7% of 2,819 total)
Follow-up: mean 6.2 months (range 0 to 26.7 months)

LP implantation was successful in 98% (197/201) of people having haemodialysis. The median procedure time was 27 minutes. There were 4 implant failures and 3 procedure-related deaths. No device-related infections or removals occurred. People included in this study had multiple comorbidities, and 72% were deemed unsuitable for TVPs.

A more recent study including people on haemodialysis has been included in table 2.

El-Chami MF, Bockstedt L, Longacre C et al. (2022)

Leadless vs. transvenous single-chamber ventricular pacing in the Micra CED study: 2-year follow-up. European Heart Journal 43(12): 1207–1215.

n=6,219 (LP) vs. n=10,212 (TVP)
Follow-up: 2 years

LP group had significantly fewer reinterventions (adjusted HR 0.6, 95% CI 0.5 to 0.9, P=0.003) and chronic complications (adjusted HR 0.7, 95% CI 0.6 to 0.8, P<0.0001) compared to TVP population. Adjusted all-cause mortality did not differ (HR 1, 95% CI 0.9 to 1, P=0.4).

A more recent publication from the same study has been included in the main evidence summary.

El-Chami MF, Al-Samadi F, Clementy N et al. (2018)
Updated performance of the Micra transcatheter pacemaker in the real-world setting: a comparison to the investigational study and a transvenous historical control.
Heart Rhythm 15(12): 1800–1807.

n=1817 (Micra PAR); mean follow-up 6.8; SD 6.9 months
Comparators: n=726 (IDE study) and n=2667 (TVP control group)

The major complication rate in Micra PAR was 3% at 12 months (95% CI 2% to 3%). Compared to TVPs, LPs had a 63% lower risk of major complications (HR 0.4, 95% CI 0.3 to 0.5, p<0.001). There were no battery or telemetry issues, and pacing thresholds remained stable.

A more recent publication from PAR study has been included in the main evidence summary.

Fagerlund BC, Harboe I, Giske L et al. (2018)

The Micra™ Transcatheter Pacing System, a leadless pacemaker, in patients indicated for single-chamber ventricular pacemaker implantation: a single technology assessment.

Norwegian Institute of Public Health.

Clinical review included data from 3 large multi-site trials (total n=1,575) and 3 smaller case series. Follow-up: up to 24 months (efficacy), 10-year horizon for cost-effectiveness model.

LP achieved satisfactory pacing thresholds in 93 to 97% of people at 12 to 24 months. Major complications occurred in 2 to 4% of people, with 4 reported device/system-related deaths. Compared to historical controls, LPs had a lower complication rate, but evidence was rated low to very low certainty due to study design (single arm) and indirectness.

More recent systematic reviews have been included in the main evidence summary.

Gangannapalle M, Monday O, Rawat A, et al. (2023)

Comparison of Safety of Leadless Pacemakers and Transvenous Pacemakers: A Meta-Analysis.

Cureus 15(9): e45086

This meta-analysis encompassed 17 studies comparing LPs and TVPs. The total number of people and specific follow-up durations varied across the included studies.​

LPs were associated with a lower risk of total complications, device-related complications, pneumothorax, endocarditis, and need for reintervention compared to TVPs. However, the risk of pericardial effusion was significantly higher in the LP group.

Comprehensive and more recent meta-analyses have been included in the main evidence summary.

Garg A, Koneru JN, Fagan DH, et al. (2020)

Morbidity and mortality in patients precluded for transvenous pacemaker implantation: Experience with a leadless pacemaker.

Heart Rhythm 17(12): 2056–2063

n=2,817, undergoing Micra implantation; 546 (19%) were precluded from TVP implantation
Follow-up: 36 months

People precluded from TVP had higher acute mortality (3% vs 1%, p=0.022) and 36-month mortality (38% vs 21%, p<0.001) than no precluded people.

Although informative for high-risk subpopulations, the comparative arm is not randomised, and the elevated mortality likely reflects baseline comorbidities rather than device performance, limiting its applicability for general evidence synthesis.

Garg J, Shah K, Bhardwaj R et al. (2023)
Adverse events associated with Aveir™ VR leadless pacemaker: a Food and Drug Administration MAUDE database study.
Journal of Cardiovascular Electrophysiology 34(9): e15932.

n=64 adverse event reports included (from post-FDA approval until January 2023)
No follow-up duration specified; real-world device surveillance study

Most common complications included high threshold/noncapture (28%), stretched helix (17%), and device dislodgement (16%). Serious adverse events included 5 cases of pericardial effusion requiring pericardiocentesis and 2 deaths (3%). The study highlights rare but serious safety concerns with the Aveir™ VR LP.

Brief communication: this study is based on voluntarily reported adverse events from a regulatory database without denominator data or follow-up, limiting its comparability to prospective clinical trials or registries.

Garweg C, Chinitz L, Marijon E, et al. (2024)

A leadless ventricular pacemaker providing atrioventricular synchronous pacing in the real-world setting: 12-Month results from the Micra AV post-approval registry.

Heart Rhythm 21(10): 1939–1947

n=801 (LP), with 12-month follow-up
Comparison: Historical cohort of 2667 people with TVPs

LP showed a significantly lower major complication rate at 12 months compared to transvenous dual-chamber pacing (4% vs 9%; HR 0.4, 95% CI 0.3 to 0.6 p<0.001) and a lower system revision rate (2% vs 6%; HR 0.3, 95% CI 0.13 to 0.5; p<0.001). Median AV synchrony index was 79% in high burden paced population.

This real-world observational registry lacks a direct comparator group within the study itself, limiting its suitability for inclusion in the main evidence summary prioritising controlled or randomised studies.

Garweg C, Vandenberk B, Jentjens S, et al. (2020)

Bacteraemia after leadless pacemaker implantation.

Journal of Cardiovascular Electrophysiology 31(9): 2440–2447

n=155, with LP implantation
Median follow-up after bacteraemia: 263 days (range: 15 to 1134)

Bacteraemia occurred in 15 people (10%) at a median of 226 days post-implantation. FDG PET/CT in 6 people showed no evidence of infection involving the pacemaker. No cases of LP related endocarditis were identified, and all infections resolved with antibiotics.

Small single-centre retrospective study with a limited number of events and lack of control group; not prioritised for inclusion in main evidence summary focused on broader or comparative outcomes.

Garweg C, Vandenberk B, Foulon S, et al. (2020)

Leadless pacemaker for patients following cardiac valve intervention.

Arch Cardiovasc Dis 113(12): 772–779.

n=170 LPs (54 post-valve intervention vs 116 controls);

Median follow-up: 12 months

LP implantation was successful in all people, including the 54 with prior cardiac valve interventions (aortic, mitral, or multiple valves). No major procedural complications occurred. Both valve intervention and control groups showed similar reduction in LVEF over 12 months, which correlated with the amount of right ventricular pacing.

Broader registry study has been added in the main summary evidence.

Garweg C, Vandenberk B, Foulon S, et al. (2019)

Leadless pacing with Micra TPS: A comparison between right ventricular outflow tract, mid-septal, and apical implant sites.

Journal of Cardiovascular Electrophysiology 30(10): 2002–2011

n=133
Mean follow-up: 13; SD 11 months

LP implantation was successful in all. across RV outflow tract (n=45), mid-septal (n=58), and apical (n=30) sites. RVOT pacing was associated with the narrowest QRS duration (142 ms vs. 159 ms mid-septal vs. 181 ms apical; p<0.001). No pericardial effusion occurred. 2 major complications were reported in the apical group. Electrical performance (pacing threshold, R-wave amplitude) was stable across all positions.

This single-centre, non-randomised observational study with modest sample size offers valuable insights into implantation site differences but lacks comparative clinical outcomes beyond electrical parameters, limiting its inclusion in the main evidence summary.

Garweg C, Ector J, Voros G, et al. (2018)

Monocentric experience of leadless pacing with focus on challenging cases for conventional pacemaker.

Acta Cardiologica 73(5): 459–468

n=66
Follow-up: mean 10.4; SD 6.1 months (range 1 to 23 months)

LP was successfully implanted in 99% of people, with stable electrical performance at follow-up. Mean pacing capture threshold was 0.6 V, impedance 580 Ohms, and R-wave sensing 10.6 mV. 1 major and 3 minor adverse events were reported. No dislodgement, infection, or pericardial effusion occurred. The device was also effective in anatomically challenging population.

Single centre with small sample size and non-comparative design limits generalisability and strength of evidence compared to larger multicentre or controlled trials.

Grubman E, Ritter P, Ellis CR, et al. (2017)

To retrieve, or not to retrieve: System revisions with the Micra transcatheter pacemaker.

Heart Rhythm 14(12): 1801–1806.

n=989 (LP group) vs. n=2667 (TVP group); up to 24 months follow-up

The 24-month revision rate for LP was 1%, statistically significantly lower than the 5% revision rate in the TVP group (75% relative risk reduction; p<0.001). No LP revisions were due to dislodgement or device-related infection. Most LP devices were disabled and left in situ; percutaneous retrieval was successful up to 14 months post-implant.

Broader registry studies have been included in the main evidence summary.

Gul EE, Baudinaud P, Waldmann V, et al. (2024)

Leadless pacemaker implantation following tricuspid interventions: multicenter collaboration of feasibility and safety.

J Interv Card Electrophysiol 67(5): 1241–1246.

n=40 with prior tricuspid valve interventions.

Mean follow-up: 10 months

All people successfully received LPs after tricuspid valve surgery or intervention. No acute complications were observed. Electrical parameters (pacing threshold: 1.4; SD 1.2 V, impedance: 772; SD 245 Ohm, R-wave: 6.9; SD 5.4 mV) remained stable through follow-up. There were 4 deaths, not procedure related.

Broader registry study has been prioritised in the main body evidence.

Gulletta S, Schiavone M, Gasperetti A, et al. (2023)

Peri-procedural and mid-term follow-up age-related differences in leadless pacemaker implantation: Insights from a multicenter European registry.

Int J Cardiol 371:197–203.

n=1154; 2 cohorts: younger (50 or less in years, 6%) and older (more than 50 years); mid-term follow-up duration not explicitly stated

In younger people, LPs were primarily chosen due to preference (47% versus 6%, p<0.001), while in older population, infectious (68%) and vascular concerns (16%) were more common indications. Periprocedural complication rate was 4% with no significant age-related difference. Younger people had higher pacing thresholds at discharge and follow-up (0.6 V versus 0.5 V, p=0.004), though device performance remained acceptable in both groups.

Age-based subgroup analysis with limited representation of younger people (6% of cohort).

Haddadin F, Majmundar M, Jabri A, et al. (2022)

Clinical outcomes and predictors of complications in patients undergoing leadless pacemaker implantation.

Heart Rhythm 19(8): 1289–1296

n=7,821
Follow-up: In-hospital and 30-day outcomes

Immediate procedure-related complications occurred in 8% of people. Specific complications included pericardial effusion (2%), pericardiocentesis (1%), vascular complications (2%), and device dislodgment.

Shorter follow up duration might not capture long term safety and efficacy outcomes. Studies with longer follow up period have been assessed in the main evidence summary.

Hai JJ, Fang J, Tam CC, et al. (2019)

Safety and feasibility of a midseptal implantation technique of a leadless pacemaker.

Heart Rhythm 16(6): 896–902

n=51
Follow-up: Median 218.7 days

Midseptal LP implantation was successfully achieved in 90% of people using fluoroscopic guidance (RAO, LAO, and lateral views).

Small, single-centre feasibility study with a short follow-up duration and limited generalisability; primarily technical in nature rather than focused on comparative safety or efficacy outcomes.

Hauser RG, Gornick CC, Abdelhadi RH, et al. (2021)

Major adverse clinical events associated with implantation of a leadless intracardiac pacemaker.

Heart Rhythm 18(7): 1132–1139

n=363 major adverse clinical events (MACE) for Micra (LP) vs. n=960 MACE for CapSureFix (TVP)
Timeframe: 2016–2020 (retrospective database review; no population-level follow-up duration)

LPs was associated with significantly more serious events: deaths (26% versus 2%), tamponade (79% versus 23%), and rescue thoracotomies (27% versus 5%) compared to TVPs (all p<0.001).

Although highlighting critical safety signals, this study is based solely on voluntary manufacturer-reported adverse event data from the MAUDE database, which lacks denominator data, standardised event adjudication, and clinical detail, limiting its reliability for inclusion in formal evidence summaries.

Hindricks G, Doshi R, Defaye P, et al. (2024)

Six-month electrical performance of the first dual-chamber leadless pacemaker.

Heart Rhythm 2024;21(1):66–73.

n=381; follow-up duration: 6 months post-implant

The Aveir DR dual-chamber LP showed stable and improving electrical performance over 6 months. Capture thresholds significantly decreased in both atrial (2.4 V to 0.8 V) and ventricular (0.8 V to 0.6 V) devices. Sensed amplitudes increased (atrial: 1.8 mV to 3.4 mV; ventricular: 8.8 mV to 11.7 mV). Impedance remained stable in the atrial device and decreased in the ventricular device. Performance did not vary by implant location. These results suggest robust and reliable pacing and sensing for dual-chamber LPs.

Short-term follow-up (6 months) in an early experience cohort; long-term outcomes and comparative effectiveness data with dual LP has been included in the main evidence summary.

Huang J, Bhatia NK, Lloyd MS, et al. (2023)

Outcomes of leadless pacemaker implantation after cardiac surgery and transcatheter structural valve interventions.

J Cardiovasc Electrophysiol 34(11): 2216–2222.

n=78; mean follow-up: 1.3; SD 1.1 years

LPs were successfully implanted in post-surgical and post-transcatheter valve intervention group, with device electrical performance over medium-term follow-up. Mean RVP burden decreased significantly (from 74% to 48%; p<.001). LVEF showed a modest decline (from 55% to 52%; p<.001). 6 people (8%) required conversion to TVPs—four due to need for cardiac resynchronisation and two for dual-chamber pacing. No device-related safety issues were highlighted.

Broader registry study has been added in the main summary evidence.

Huang J, Bhatia NK, Lloyd MS, et al. (2024)

Impact of omitting the intravenous heparin bolus on outcomes of leadless pacemaker implantation.

J Cardiovasc Electrophysiol 35(6):1212-1216.

n=621 LP implantations; 326 with heparin bolus, 243 without, 52 excluded due to unknown status; median follow-up: 14.3 months

No statistically significant differences were observed between heparin bolus and no-bolus groups in terms of procedural complications (hematoma, pseudoaneurysm, cardiac perforation, thrombus formation), 30-day readmission or mortality, or implant electrical parameters.

Operators chose anticoagulation strategy, possibly reflecting population-level confounders not fully adjusted.

Hofer D, Regoli F, Saguner AM, et al. (2023)

Efficacy and Safety of Leadless Pacemaker Implantation in Octogenarians.

Cardiology 148(5): 441–447

n=220 (of which 124 were 80 years or more)
Follow-up: Not explicitly stated; included procedural and post-implant follow-up measurements

Implantation in octogenarians was found to be safe and effective, with a high success rate (99%) and a low major complication rate (3%). Procedural time and radiation exposure were slightly higher in people more or equal to 80 years, but post-procedural outcomes and device performance were comparable to younger people.

While relevant for older adults, the study's retrospective design, limited follow-up duration, and non-comparative structure reduce its strength for informing this evidence summaries.

Ip JE, Rashtian M, Exner DV, et al. (2024)

Atrioventricular Synchrony Delivered by a Dual-Chamber Leadless Pacemaker System.

Circulation 150(6): 439–450

n=464 enrolled; n=384 evaluable (83%)
Follow-up: 3 months post-implantation

Achieved a mean atrioventricular (AV) synchrony of 98% across all evaluated beats and postures, outperforming atrial-to-ventricular and ventricular-to-atrial i2i communication success rates (both 94%; p<0.001). AV synchrony more than 95% was maintained consistently across various postures (sitting, standing, supine, lateral recumbency), activity levels (walking, fast walking), implantation indications, AV event types, and heart rates including more than 100 bpm.

The study's follow-up period was limited to 3 months, which may not capture long-term performance and safety outcomes, which restricts its inclusion in evidence summaries prioritising long-term comparative data from randomised or controlled observational studies.

Jelisejevas J, Regoli F, Hofer D, et al. (2024)

Leadless Pacemaker Implantation in Patients with a Prior Conventional Pacing System.

CJC Open 6(4): 649–655

n=257

Implantation was successful and safe in people with prior conventional pacing systems (CPS). There were no major complications in the prior CPS group, including those who underwent lead extraction due to infection. No infections were recorded post-LP implantation, even when LP implantation followed device-related infection. Electrical parameters at implant and follow-up were comparable between groups. Major complications occurred in 3% of the full cohort (none in the prior CPS group).

Despite its relevance, the study's small subgroup size for prior CPS people (n=24), retrospective design, and limited generalisability restrict its inclusion in main evidence summaries prioritising large-scale or prospective comparative studies.

Jelisejevas J, Regoli F, Hofer D, et al. (2023)

Leadless Pacemaker Implantation, Focusing on Patients With Conduction System Disorders Post-Transcatheter Aortic Valve Replacement: A Retrospective Analysis.

CJC Open 6(2Part A): 96–103.

n=257 (26 with post-TAVR bradycardia; 231 non-TAVR controls); follow-up duration not explicitly reported, but complications assessed within 30 days post-implantation.

The implantation success rates were 100% in TAVR and 99% in non-TAVR groups. No significant differences were found in pacing parameters (sensing, impedance, and threshold) at implantation or during follow-up. The major complication rate was similarly low (4% in TAVR versus 3% in non-TAVR).

Broader registry study has been prioritised in the main summary evidence.

Jelisejevas J, Breitenstein A, Hofer D, et al. (2021)

Left femoral venous access for leadless pacemaker implantation: patient characteristics and outcomes.

Europace 23(9): 1456–1461

n=143 (125 right femoral access, 18 left femoral access)
Follow-up: Mean 15; SD 11.5 months

Left femoral venous access for LP implantation was safe and effective, with procedural success and device parameters comparable to the conventional right-sided approach. All 5 major complications (4%) occurred with right-sided access. Left-sided access was more commonly used following transfemoral TAVI (42% versus 8%, P=0.003).

While informative, the small sample size for left-sided access (n=18) and single-centre retrospective design limit generalisability

Katsuki T, Nagashima M, Kono H, et al. (2022)

Clinical outcome for heart failure hospitalizations in patients with leadless pacemaker.

Journal of Arrhythmia 38(5): 730–735

n=929 (368 LPs vs. 561 TVPs)

Median follow-up: 1.7 years (IQR 0.8–2.6 years)

People with LPs had a significantly higher risk of heart failure hospitalisation than those with conventional pacemakers (adjusted HR 1.7; 95% CI 1.1 to 2.6; p=0.01).

The study's retrospective design and observational nature limit the ability to establish causality between pacemaker type and heart failure hospitalisation. Additionally, the median follow-up duration of 1.7 years may not be sufficient to capture long-term outcomes associated with different pacemaker types.

Kempa M, Mitkowski P, Kowalski O, et al. (2021)

Expert opinion of a Working Group on Leadless Pacing appointed by the National Consultant in Cardiology and the Board of the Heart Rhythm Section of the Polish Cardiac Society.

Kardiologia Polska 79(5): 604–608.

Not applicable (policy and guidance document; no population cohort analysed)

Endorsed LPs as a safe and effective alternative to traditional TVPs, particularly when infection risk or venous access issues exist. Highlighted positive outcomes from international clinical trials confirming LP safety and efficacy. Provided Polish-specific guidance including - indications and contraindications for LP use, emphasis on procedural expertise and proper center accreditation for implantation and called for formal reimbursement frameworks in Poland to increase access.

This is an expert consensus document providing recommendations for clinical practice in Poland, not an original empirical study with a population cohort.

Khan MZ, Nguyen A, Khan MU, et al. (2024)

Association of chronic kidney disease and end-stage renal disease with procedural complications and inpatient outcomes of leadless pacemaker implantations across the United States.

n=29,005 LP implantations (CKD: n=5,245 [18.1%]; ESRD: n=3,790 [13.1%])

In-hospital outcomes only (no post-discharge follow-up)

CKD and ESRD were significantly associated with increased inpatient mortality.

Focused only on in-hospital outcomes.

Khan MZ, Nassar S, Nguyen A, et al. (2024)

Contemporary trends of leadless pacemaker implantation in the United States.

Journal of Cardiovascular Electrophysiology 35(7): 1351–1359

Data from 2016–2020, showing growth from 3,230 LP implants (2016–2017) to 11,815 implants (2020)
Follow-up: In-hospital outcomes only

LP implantations steadily increased in the US over the study period. Adjusted in-hospital mortality significantly declined (2018: aOR 0.6; 2019: aOR 0.5; 2020: aOR 0.5, all p<0.01) compared to 2016 to 2017.

Trend study, not aligned with the objective of this overview.

Kiani S, Black GB, Rao B, et al. (2019)

Outcomes of Micra leadless pacemaker implantation with uninterrupted anticoagulation.

Journal of Cardiovascular Electrophysiology 30(8): 1313–1318

n=170 (OAC group: n=26; Off-OAC group: n=144)
Follow-up: Not explicitly stated, complete in-hospital and procedural data

Implantation with uninterrupted anticoagulation (OAC) was safe and feasible. The composite complication rate was similar between OAC and Off-OAC groups (4% versus 1%; P=0.761), with no significant difference in length of stay (1.3; SD 2.6 vs 2.3; SD 3.4 days; P=0.108).

Focused on a specific subset of population, also the sample size is smaller.

Kiani S, Black GB, Rao B, et al. (2019)

The Safety and Feasibility of Same-Day Discharge After Implantation of MICRA Transcatheter Leadless Pacemaker System.

n=167 (Same-day discharge [SD] group: n=25; Hospitalised overnight [HD] group: n=142)
Follow-up: 45 days

Same-day discharge after LP implantation was safe and feasible. No major complications occurred in the SD group vs. 4% in the HD group (P=1.00), with similar rates of individual complications such as access site issues, pericardial effusion, dislodgement, or device revision.

The study did not capture long term safety and efficacy outcomes.

Kiblboeck D, Blessberger H, Ebner J, et al. (2024)

Feasibility, timing and outcome of leadless cardiac pacemaker implantation in patients undergoing cardiac implantable electronic device extraction.

Clin Res Cardiol 2024 Aug 12. doi: 10.1007/s00392-024-02516-0

n=48, undergoing CIED extraction (38 for infection, 10 for dysfunction); median follow-up 15 months (IQR 12 to 41)

LP implantation was feasible in 98% of people undergoing CIED extraction, with 67% receiving the LP in a single procedure. Complete CIED removal was achieved in 92% overall and 97% of infected cases. In-hospital mortality was 6%, and 1-year survival was 85%. No LP-related mortality or recurrent infections occurred during follow-up.

Covered in the systematic review included in the main evidence body.

Knops RE, Tjong FVY, Neuzil P, et al. (2015)

Chronic performance of a leadless cardiac pacemaker: 1-year follow-up of the LEADLESS trial.

Journal of the American College of Cardiology 65(15): 1497–1504

n=31 (implanted with LPs)
Follow-up: 12 months

Demonstrated stable electrical performance at 6 and 12 months, with mean pacing thresholds of 0.40; SD 0.3 V (6 months) and 0.43; SD 0.3 V (12 months), R-wave amplitudes of 10.6; SD 2.6 mV and 10.3; SD 2.2 mV, and impedance of 625; SD 205 ohms and 627; SD 209 ohms, respectively.

Small sample size and single-arm design without comparator group limits generalisability and prevents comparative assessment with conventional pacing systems.

Kowlgi GN, Tseng AS, Tempel ND, et al. (2022)

A real-world experience of atrioventricular synchronous pacing with leadless ventricular pacemakers.

J Cardiovasc Electrophysiol 33(5):982–993.

n=56 with LP implants; minimum follow-up 3 months

65% of people achieved atrial synchronous ventricular pacing (AVP) equal or more than 70%. Higher AV synchrony was associated with lower BMI, fewer comorbidities (e.g., heart failure), and prior cardiac surgery.

Covered by systematic review included in the main evidence summary.

Lenormand T, Abou Khalil K, Bodin A et al. (2023)

Comparison of first- and second-generation leadless pacemakers in patients with sinus rhythm and complete atrioventricular block.

Journal of Cardiovascular Electrophysiology 34(8): 1730–1737.

n=93 (45 first-generation Micra VR, 48 second-generation Micra AV)
Follow-up: At least 1 year

Second-generation Micra AV pacemakers achieved atrioventricular synchrony (median AV-synchronous beats: 78%) and were associated with significantly lower incidence of pacemaker syndrome (0% versus. 11% in Micra VR group, p=0.02).

Focused on head-to-head comparison between device generations rather than broader safety/effectiveness outcomes. Small sample size and short-term follow-up limit generalisability.

Lenormand T, Abou Khalil K, Bodin A et al. (2023)

Leadless cardiac pacing: Results from a large single-centre experience.

Archives of Cardiovascular Disease 116(6-7): 316–323.

n=400 (328 Micra VR, 72 Micra AV)
Follow-up: Median 16 months (694 person-years)

Implantation success was 100%. At 30 days, perioperative complication rate was 4%, and 88% of people were discharged the next day.

Single-centre retrospective study without a comparator group or stratified outcome data; limits generalisability.

Li B, Allen JC, Arps K, et al. (2022)

Leadless pacemaker implantation after lead extraction for cardiac implanted electronic device infection.

J Cardiovasc Electrophysiol 33(3): 464–470.

n=39; mean follow-up 24.8; SD 14.7 months

LP implantation following extraction of infected cardiac devices was associated with low complication rates and no recurrence of infection during the 2-year follow-up. Among 3 major complications (8%), none were infections.

Covered in systematic review included in main evidence summary.

Loring Z, North R, Hellkamp AS, et al. (2020)

VVI pacing with normal QRS duration and ventricular function: MOST trial findings relevant to leadless pacemakers.

Pacing and Clinical Electrophysiology 43(12): 1545–1553.

n = 1284 (subset of the original 2010 MOST participants)

Inclusion: LVEF more than 35%, QRS duration less than 120 ms, no prior ICD or ventricular arrhythmias

Follow-up: 4 years

VVIR pacing, typical of most LPs, does not increase the risk of death, stroke, or heart failure hospitalisation compared to DDDR pacing.

However, it significantly increases the risk of new-onset AF, especially in people without a history of AF.

Focused on pacing mode effects in LP-eligible populations, particularly highlighting the AF risk tradeoff with VVIR mode pacing typical in current LP devices.

Mararenko A, Udongwo N, Pannu V, et al. (2023)

Intracardiac leadless versus transvenous permanent pacemaker implantation: Impact on clinical outcomes and healthcare utilization.

J Cardiol 82(5):378–387.

n=21,782 (mean age 81.1 years, 46% female); follow-up focused on 30-day readmissions and in-hospital outcomes

No significant difference in 30-day readmission (HR 1.1, 95% CI 0.9 to 1.4) or inpatient mortality (HR 1.4, 95% CI 0.7 to 2.6) between LP and TVP groups. Length of stay was slightly longer for LP recipients (0.5 days; p<0.001).

Covered in systematic review included in main evidence summary.

Martínez-Sande JL, García-Seara J, Rodríguez-Mañero M et al. (2017)

The Micra Leadless Transcatheter Pacemaker. Implantation and Mid-term Follow-up Results in a Single Center.

Revista Española de Cardiología (English Edition) 70(4): 275–281.

n=30 (65 years or more);
Mean follow-up: 5.3; SD 3.3 months (range up to more than 1 year in 4 people)

Successful implantation was achieved in all. Electrical pacing and sensing parameters remained stable from implantation through follow-up. 1 moderate pericardial effusion occurred without tamponade; otherwise, no severe complications were observed.

Small single-centre study with limited follow-up duration and generalisability. Also, concurrent procedures were assessed.

Martinez-Sande JL, Garcia-Seara J, Gonzalez-Melchor L, et al. (2021)

Conventional single-chamber pacemakers versus transcatheter pacing systems in a "real world" cohort of patients: A comparative prospective single-center study.

Indian Pacing Electrophysiol J 21(2):89–94.

n=443 (LP: n=198, TVP: n=245); mean follow-up 22.3; SD 15.9 months

LP recipients had significantly fewer overall complications compared to TVP groups (HR 0.4, 95% CI 0.2 to 1; p=0.013), with a 96% probability of lower risk in Bayesian analysis. No significant differences in major complications (LP 3% versus TVP 6%; p=0.1761) or mortality.

Covered in systematic review included in the main body evidence.

Mitacchione G, Schiavone M, Gasperetti A, et al. (2023)

Sex differences in leadless pacemaker implantation: A propensity-matched analysis from the i-LEAPER registry.

Heart Rhythm 20(10):1429–1435.

n=1179 (64% male); after matching, n=738 (1:1 matched); median follow-up: 25 months (IQR 24 to 39)

There were no statistically significant sex differences in major complication rates (HR 2.03; 95% CI 0.7 to 5.8; p=.190) or all-cause mortality (HR 1; 95% CI 0.4 to 2.4; p=.96). LP performance was similar between men and women, although women had slightly higher pacing impedance at implant and follow-up (670 ohms vs 616 ohms at 24 months; p=.014), remaining within acceptable ranges. Women were underrepresented among LP recipients.

While sex-specific findings are valuable, the analysis was exploratory and not powered to detect small differences in adverse outcomes. No impact on safety or efficacy was observed despite impedance variation.

Molina-Lerma M, Cózar-León R, García-Fernández FJ, Calvo D. (2024)

Spanish pacemaker registry. 21st official report of Heart Rhythm Association of the Spanish Society of Cardiology (2023).

Rev Esp Cardiol (Engl Ed) 77(11):947–956.

112 hospitals participated

24,343 LP implantations reported in 2023

No specific population-level follow-up data provided

Marked 48% increase in reported device implantations compared to 2022. LPs saw an 18% rise, with 963 devices implanted. AV block remained the top indication; atrial tachyarrhythmia with slow ventricular response ranked second for the first time.

This is a national registry report summarising implantation trends and system use in Spain, not a clinical trial or comparative study measuring population outcomes.

Molina-Linde JM, Díaz-Infante E, Tercedor-Sánchez L, et al. (2023)

The VR leadless pacemaker: Results of an expert panel using the RAND/UCLA method.

Pacing Clin Electrophysiol 46(5):358–364.

Involved expert evaluation of 256 clinical scenarios, 64 for people with AF, 192 for people in sinus rhythm. Follow-up not applicable; no population-level outcome data

The panel created appropriateness criteria for VR LP implantation. Limitation of vascular access via the superior vena cava was the strongest predictor for recommending LPs in both groups. Additional relevant variables included: life expectancy, risk of infection, presence of prosthetic valves, LVEF and population mobility and exercise capacity.

It provides expert-based recommendations rather than empirical outcome data.

Nair DG, Exner DV, Hadadi C et al. (2024)

Early real-world implant experience with a helix-fixation ventricular leadless pacemaker.

Journal of Interventional Cardiac Electrophysiology 67: 1539–1545.

n=167

Follow-up: 30 days post-implant

Implantation of the helix-fixation Aveir VR was successful in 99% of cases, with 98% free from acute adverse events.

Short-term follow-up (30 days), limited to initial commercial rollout without comparator group, and focused only on procedural outcomes.

Neuzil P, Exner DV, Knops RE, et al. (2025)

Worldwide Chronic Retrieval Experience of Helix-Fixation Leadless Cardiac Pacemakers.

J Am Coll Cardiol 85(11):1111–1120.

n=233 subjects with 234 retrieval attempts (mean retrieval time = 3.2 years, range 0.2 to 9 years post-implant)

The chronic retrieval success rate for helix-fixation LPs was 88% (205/234). Failures were mostly due to inability to access the docking button (86%). Retrieval-related complications occurred in 4% of people (9/233), with 11 total complications. Time since implantation (up to 9 years) did not statistically significantly affect retrieval success (p=0.71).

Focused on device retrieval safety and feasibility rather than on comparative effectiveness or long-term pacing outcomes of LPs versus TVPs.

Ngo L, Nour D, Denman RA et al. (2021)

Safety and Efficacy of Leadless Pacemakers: A Systematic Review and Meta-Analysis.

Journal of the American Heart Association 10(13): e019212.

36 studies included
Micra: n=1608 (90-day data), n=3194 (1-year data)
Nanostim: variable, fewer studies
Follow-up: up to 1 year

LPs showed a low pooled complication rate (less than 1% at 90 days and 2% at 1 year) and excellent pacing capture threshold maintenance (99% with less than or equal to 2V at 1 year).

More recent systematic reviews with inclusion of studies with longer follow up duration have been covered in the main evidence summary.

Nicosia A, Iacopino S, Nigro G et al. (2022)

Performance of transcatheter pacing system use in relation to patients' age. Journal of Interventional Cardiac Electrophysiology 65(1): 103–110.

n=577
Follow-up: Not explicitly stated; electrical parameters and safety outcomes assessed at implant and last follow-up

LP implantation was found to be safe and effective across all age groups (less than 70, 70 to77, 78 to83, and 83 and above years). Procedural complications were rare (less than 1%) and did not differ significantly by age group, despite greater frailty in older people. No cases of cardiac tamponade were reported. Electrical performance remained stable and comparable across all ages.

A larger study with similar subgroup of people was included in the main evidence summary.

Noor TA, Rana MOR, Kumari S et al. (2023)

Outcomes of primary leadless pacemaker implantation: A systematic review. Annals of Noninvasive Electrocardiology 28(6): e13084.

n=1276 across 4 included studies

Follow-up duration not consistently reported across all studies

LPs had shorter procedure and fluoroscopy times compared to temporary or TVPs in some studies. Major complications and mortality were not significantly different, and pacing parameters (threshold, impedance, sensing) were comparable. Hospital stay was generally shorter with LPs. The review suggests LPs may be an effective and safer alternative even in urgent/emergency pacing situations.

More recent systematic reviews have been included in the main evidence summary.

Oates CP, Breeman KTN, Miller MA, et al. (2024)

Long-Term Safety and Efficacy of Intraoperative Leadless Pacemaker Implantation During Valve Surgery.

JACC: Clinical Electrophysiology 10(10): 2224–2233.

n=100; median follow-up duration: 10.6 months (IQR: 2 to 22.7 months)

Intraoperative LPs implantation during valve surgery was successful in all, with no device-related complications during follow-up. At 12 months, 95% of people maintained acceptable pacing thresholds (2.0 V or lower at 0.24 ms). The cohort included 99% with tricuspid valve involvement and 78% undergoing multivalve surgery.

Broader registry study has been included in the main evidence summary.

Oates CP, Basyal B, Whang W, et al. (2024)

Trends in safety of catheter-based electrophysiology procedures in the last 2 decades: A meta-analysis.

Heart Rhythm 21(9): 1718–1726.

n=43,914 across 174 studies
Includes:

Vascular complication rates remained unchanged. Results suggest that procedural safety of catheter-based electrophysiology, including LP implantation, has improved over time despite increased usage.

It included multiple other procedures alongside LPs.

Pagan E, Gabriels J, Khodak A, et al. (2020)

Safety of leadless pacemaker implantation in the very elderly.

Heart Rhythm 17(12):2023–2028.

n=302, aged 85 years or more (LP: n=183; TVP: n=119); follow-up not specified; focused on in-hospital procedural outcomes

LP implantation in very elderly people was successful in 98% and associated with similar procedure-related complication rates compared to TVP (3% vs 6%, p=0.276). LP group had significantly shorter procedure times (35.7; SD 23 minute versus 62.3; SD 31.5-minute, p<0.001). No significant differences in pericardial effusion, hematoma, or lead dislodgement rates.

Covered in systematic review included in the main evidence summary.

Palmisano P, Guido A, Panico V, et al. (2021)

Leadless pacemaker versus transvenous single-chamber pacemaker therapy: peri-procedural aspects, utilization of medical resources and patient acceptance.

Expert Review of Medical Devices 18(5): 483–491.

n=154 (77 matched pairs: LP versus TVP)
Follow-up: baseline, 1 week, 3 months, and 6 months

L-PM implantation was associated with longer procedural time (42.2;SD 16.3 vs. 28.9;SD 11.9 minutes; p<0.001) but lower intra- and post-operative pain, shorter hospitalisation (3.2;SD 0.5 vs. 3.5;SD 1.1 days; p=0.034), greater acceptance (FPAS score: 58.7;SD 7.1 vs. 40.5;SD 4.1; p<0.001), and better quality of life on physical and mental health scales at all timepoints.

Single-centre study with a relatively small sample size; findings may not be generalisable to broader populations. Outcomes such as complication rates and long-term device performance were not the primary focus.

Palmisano P, Iacopino S, De Vivo S, et al. (2022)

Leadless transcatheter pacemaker: Indications, implantation technique and peri-procedural patient management in the Italian clinical practice.

International Journal of Cardiology 365: 49–56.

n=782
Median follow-up: 20 months

Implantation of L-PMs was primarily chosen due to high infection risk (30% of people). The implantation success rate was 99%, with 90% of devices implanted septally.

Focused on per-procedural patient management.

Palmisano P, Facchin D, Ziacchi M, et al. (2023)

Rate and nature of complications with leadless transcatheter pacemakers compared with transvenous pacemakers: results from an Italian multicentre large population analysis.

EP Europace 25(1):112–120.

n=2669 total (LP: n=665; TVP: n=2004); matched cohort: n=884 (442 LP versus 442 TVP); median follow-up: 39 months

LP group had significantly lower 12-month device-related complication rate (1% versus 2%, p=0.009). In the matched analysis, LP was associated with fewer late complications (more than 30 days; p=0.031), while early complication risk was similar (p=1.000). All LP complications occurred early, whereas 75% of TVP complications were lead- or pocket-related.

Covered in the systematic review included in the main evidence summary.

Piccini JP, Stromberg K, Jackson KP, et al. (2017)

Long-term outcomes in leadless Micra transcatheter pacemakers with elevated thresholds at implantation: Results from the Micra Transcatheter Pacing System Global Clinical Trial.

Heart Rhythm 14(5):685–691.

LP cohort: n=711

Capture (TVP) cohort: n=538

Follow-up: up to 6 months

12% LP populations had an initial pacing threshold more than 1 V at 0.2 ms pulse width. Thresholds statistically significantly decreased over time (p<.001), with 87% of those with high thresholds (1 to 1.5 V) and 85% of those with very high thresholds (more than 1.5 V) showing improvement by 6 months. Only 18% of people with an initial threshold more than 2 V achieved a threshold at 1 V or less at 6 months.

Primarily focuses on threshold behavior post-implant rather than broader clinical outcomes or direct device comparisons, might be informative for procedural decision-making.

Piccini JP, Stromberg K, Jackson KP, et al. (2019)

Patient selection, pacing indications, and subsequent outcomes with de novo leadless single-chamber VVI pacing.

Europace 21(11):1686–1693.

n=720, successfully implanted with LP; 228 (32%) had non-AF indications; follow-up: 24 months

The study found that 32% of LP implants were for non-AF-related indications, mainly due to expectations of infrequent pacing (66%) or advanced age (27%). Non-AF people had significantly lower VP needs (median 13%) compared to AF people (68%; p<0.001). The 24-month risk of the composite outcome (cardiac failure, pacemaker syndrome, or syncope) was low (2%) and similar between groups (HR 1.4; 95% CI 0.5 to 4.2; p=0.59), supporting the safety and feasibility of leadless pacing in selected non-AF population.

The analysis was limited to the Micra IDE cohort and lacked direct comparisons with transvenous pacing or atrioventricular synchronous pacing outcomes

Piccini JP, El-Chami M, Wherry K, et al. (2021)

Contemporaneous Comparison of Outcomes Among Patients Implanted with a Leadless vs Transvenous Single-Chamber Ventricular Pacemaker.

JAMA Cardiol 6(10):1187–1195.

n=15,408 (LP: n=5746; TVP: n=9662); acute outcomes at 30 days and complications at 6 months

LP recipients had higher unadjusted acute complication rates (8% versus 7%; p=.02) and more pericardial effusions/perforations (1% vs 0.4%; p=.004). However, after adjusting for population characteristics, the overall acute complication rate was similar (8% vs 7%). LP recipients had significantly fewer 6-month complications than TVP recipients (adjusted HR 0.8; 95% CI, 0.6 to 1; p=.02).

Covered by the systematic review included in the main evidence summary.

Reddy VY, Exner DV, Cantillon DJ, et al. (2015)

Percutaneous implantation of an entirely intracardiac leadless pacemaker.

New England Journal of Medicine 373(12): 1125–1135.

n=526 enrolled; primary cohort: n=300, with 6-month follow-up

Successfully implanted in 96% of people. In the primary cohort, the combined efficacy endpoint (maintaining an acceptable pacing threshold less or equal to 2 V at 0.4 msec and R-wave amplitude more or equal to 5.0 mV through 6 months) was met in 90% of people, and the safety endpoint (freedom from device-related serious adverse events) was met in 93% of people.

The study evaluated the Nanostim LP, which is no longer available due to safety concerns, limiting the applicability of its findings to current clinical practice.

Reddy VY, Knops RE, Sperzel J et al. (2014)
Permanent leadless cardiac pacing: results of the LEADLESS trial.
Circulation 129(14): 1466–1471.

n=33
Follow-up: 3 months

Implant success rate was 97% (32/33). 1 person experienced right ventricular perforation and died following a stroke; the overall complication-free rate was 94%. Pacing parameters remained stable or improved over the 3-month period.

The small sample size, Nanostim device inclusion and short follow-up period limit the generalisability of the findings.

Reynolds D, Duray GZ, Omar R, et al. (2016)

A Leadless Intracardiac Transcatheter Pacing System.

New England Journal of Medicine 374(6):533–541.

n=725 enrolled; n=719 (99%) received successful implantation; primary safety and efficacy assessed at 6 months

LPs met both prespecified safety (96% free from major complications; p<0.001 versus goal of 83%) and efficacy (98% with low, stable pacing thresholds; p<0.001 versus goal of 80%) targets. No device dislodgements occurred. Post hoc comparison with a TVP cohort (n=2667) showed a statistically significantly lower major complication rate (HR 0.5; 95% CI, 0.3 to 0.8; p=0.001).

Covered in the systematic review included in the main evidence summary.

Regoli FD, Saguner AM, Auricchio A, et al. (2023)

Peri-Procedural Management of Direct-Acting Oral Anticoagulants (DOACs) in Transcatheter Miniaturized Leadless Pacemaker Implantation.

J Clin Med 12(14):4814.

n=392, undergoing LP implantation; 282 on anticoagulation, including 192 on DOACs. No specific long-term follow-up duration stated—focused on peri-procedural outcomes.

A standardised DOAC management approach—skipping 1 dose before the procedure and resuming 6 to 24 hours afterward—was used in 115 people (Group 1A) and compared to alternative strategies in 77 (Group 1B). The incidence of major peri-procedural complications was low and similar in both groups (3% in 1A vs 4% in 1B; p=0.685). Group 1A people were more likely to undergo elective implantation and had better overall clinical profiles. No significant increase in bleeding or thromboembolic events was observed with the standardised DOAC protocol.

While relevant for procedural safety, the study focused on anticoagulation strategy rather than comparing pacemaker systems or long-term device-related outcomes.

Ritter P, Duray GZ, Steinwender C, et al. (2015)

Early performance of a miniaturized leadless cardiac pacemaker: the Micra Transcatheter Pacing Study.

European Heart Journal 36(37): 2510–2519.

n=140

Follow-up: Mean 1.9; SD 1.8 months; 3-month outcomes reported in 60 people

Met both safety and efficacy endpoints. No unanticipated serious adverse device events were reported. Among 60 people with 3-month follow-up, all had pacing thresholds less than 2 V, with a mean threshold of 0.5; SD 0.2 V. 1 case of pericardial effusion occurred without tamponade.

Short follow-up period and limited 3-month data on a subset (n=60) reduce confidence in long-term outcomes.

Roberts PR, Clémenty N, Mondoly P, et al. (2023)

A leadless pacemaker in the real-world setting: Patient profile and performance over time.

Journal of Arrhythmia 39(1): 1–9.

n=928
Mean follow-up: 9.7; SD 6.5 months

Confirmed a high implant success rate (100%) and a low 30-day major complication rate (3%) for LPs, consistent with earlier IDE and PAR studies. Electrical performance was stable through 12 months, with a mean pacing threshold of 0.6; SD 0.4 V.

Broader real-world studies with larger sample size have been emphasised in main evidence summary.

Roberts PR, Clementy N, Al Samadi F, et al. (2017)

A leadless pacemaker in the real-world setting: The Micra Transcatheter Pacing System Post-Approval Registry.

Heart Rhythm 14(9): 1375–1379.

n=795 (implant success in 792; 99.6%)
Follow-up: 30 days post-implant

100% implant success rate and a low 30-day major complication rate of 1.5%. Key complications included cardiac effusion, device dislodgement, and sepsis.

The short follow-up period limits the assessment of long-term safety and efficacy outcomes.

Roberts PR, Pepper C, Rinaldi CA, et al. (2019)

The use of a single chamber leadless pacemaker for the treatment of cardioinhibitory vasovagal syncope.
Int J Cardiol Heart Vasc 23:100349.

n=32

Follow-up: mean 404; SD 237 days (range: 63 to 928 days)

Implantation was successful in all people, with a major complication rate of 3%. After follow-up, 87% of people were symptom-free, suggesting good efficacy. The study supports the feasibility and potential benefit of leadless pacing in this younger syncope population.

Limited sample size and observational design without a control group limit the generalisability and strength of conclusions regarding efficacy compared to conventional pacemakers or other management strategies.

Russo V, D'Andrea A, De Vivo S, et al. (2021)

Single-Chamber Leadless Cardiac Pacemaker in Patients Without Atrial Fibrillation: Findings from Campania Leadless Registry.

Frontiers in Cardiovascular Medicine 8: 781335.

n=140
Mean follow-up: 606.5; SD 265.9 days

No significant difference in perioperative complications (5%), cardiac hospitalisation (5%), syncope (4%), or all-cause mortality (8%) was observed between AF and non-AF groups. No pacemaker syndrome was reported in either group.

Evidence with larger sample size have been prioritised in main evidence summary.

San Antonio R, Chipa-Ccasani F, Apolo J, et al. (2019)

Management of anticoagulation in patients undergoing leadless pacemaker implantation.

Heart Rhythm 16(12):1849–1854.

n=107 (consecutive people receiving LPs between 2014 and 2018)

Among 107 people, 43 (40%) received anticoagulation. Anticoagulation was managed via temporary discontinuation or continuation. Only 2 people experienced complications: 1 haemorrhagic pericardial effusion and 1 saphenous vein thrombosis (not on anticoagulants).

Single-centre study with a modest sample size and no comparator group limits the generalisability of conclusions regarding anticoagulation safety across broader populations or different procedural techniques.

Sanchez R, Nadkarni A, Buck B, et al. (2021)

Incidence of pacing-induced cardiomyopathy (PICM) in pacemaker-dependent patients is lower with leadless pacemakers compared to transvenous pacemakers.

Journal of Cardiovascular Electrophysiology 32(2):477–483.

n=198 pacemaker-dependent people (TVP: n=131; LP: n=67) with baseline LVEF equal or more than 50%; mean follow-up: TVP 592; SD 549 days, LP 817; SD 600 days

PICM (equal and more than10% LVEF reduction) occurred more often in TVP recipients (14%) than LP recipients (3%; p=0.02). TVP was an independent predictor of PICM (OR: 1.1), while older age reduced the risk (OR: 0.9). Nearly all people responded to CRT, including both LP cases that developed PICM.

Covered by systematic review included in the main evidence summary.

Sasaki K, Togashi D, Nakajima I, et al. (2022)

Clinical outcomes of non-atrial fibrillation bradyarrhythmias treated with a ventricular demand leadless pacemaker compared with an atrioventricular synchronous transvenous pacemaker: A propensity score-matched analysis.

Circulation Journal 86(8):1283–1291.

n=193 total; matched cohort: n=116 (58 in each group with LP or TVP); median follow-up 733 days (IQR: 395 to 997)

Although late device-related adverse event rates were not statistically significantly different (0% versus 4%; p=0.155), people receiving LP had statistically significantly higher HF-related readmission (29% versus 2%; p=0.001) and a trend toward higher all-cause mortality (28% versus 4%; p=0.059) compared to TVP recipients.

Covered in the systematic review included in the main body evidence.

Schiavone M, Gasperetti A, Mitacchione G, et al. (2022)

Leadless Pacemaker Implantation in the Emergency Bradyarrhythmia Setting: Results from a Multicenter European Registry.

Medicina 59(1): 67.

n=1154 with 6% presenting from emergency departments (ED+)
Periprocedural outcomes only (no long-term follow-up reported)

Implantation for urgent bradyarrhythmias (ED+) was feasible and did not significantly increase the rate of major complications compared to elective implantations (ED−) (7% vs. 4%, p=0.244).

Short-term outcomes only; limited sample size for the emergency group and no follow-up beyond the procedural period.

Semlitsch T, Loder C (2020)

Leadless pacemaker for right ventricle pacing (Update 2020).

Decision Support Document 97 / Update 2020. Austrian Institute for Health Technology Assessment (AIHTA).

n=2,976 across 16 new documents (3 ongoing multicentre single-arm studies, 1 multicentre case-control study, 5 monocentre case series)

The update identified limited evidence for comparative efficacy versus conventional pacemakers. However, LP showed consistent safety advantages, particularly in avoiding complications related to subcutaneous pockets and transvenous leads.

Evaluated as a policy-level update and synthesis of ongoing observational evidence rather than a new clinical study with direct comparative outcomes.

Shantha G, Brock J, Singleton MJ, et al. (2023)

A comparative study of the two leadless pacemakers in clinical practice.

Journal of Cardiovascular Electrophysiology 34(9): 1896–1903.

n=50 (25 AVEIR-VR, 25 MICRA-VR) with 8 weeks of follow-up

Both devices had 100% implant success and stable pacing parameters. AVEIR-VR had more single-attempt deployments (80% versus 60%), a higher rate of ventricular arrhythmias (20% versus 0%; p=.043), and a significantly longer estimated battery life (15 versus 8 years; p=.047). No significant procedural complications or dislodgements occurred.

Small sample size and short follow-up period; initial experience rather than long-term outcomes.

Sharma P, Guleria VS, Bharadwaj P et al., (2020)
Assessing safety of leadless pacemaker (MICRA) at various implantation sites and its impact on paced QRS in Indian population.
Indian Heart Journal 72(5): 376–382.

n=35 with mean follow-up of 1.4 years

Mid-septal LP implantation resulted in the narrowest paced QRS duration (139.3 ms), while apical placement had the broadest (166.6 ms). Left ventricular ejection fraction and pacing thresholds remained stable across all groups. 2 minor complications were reported (pericardial effusion and diaphragmatic pacing).

The small sample size and single-centre design may limit the generalisability of the findings.

Shtembari J, Shrestha DB, Awal S, et al. (2023)

Comparative assessment of safety with leadless pacemakers compared to transvenous pacemakers: a systematic review and meta-analysis.

Journal of Interventional Cardiac Electrophysiology 66(12): 2165–2175.

17 studies included population numbers varied (exact pooled n not reported); follow-up duration not uniformly stated across studies

LPs had 42% lower odds of overall complications compared to TVPs (OR 0.6, 95% CI 0.4 to 0.8). LPs showed significantly lower risks for device dislodgment (OR 0.3), re-intervention (OR 0.5), and pneumothorax (OR 0.1). However, LPs were associated with higher odds of pericardial effusion (OR 2.7). All included studies were observational.

More comprehensive systematic reviews and meta-analyses have been covered in the main evidence summary.

Soejima K, Asano T, Ishikawa T, et al. (2017)

Performance of leadless pacemaker in Japanese patients vs. rest of the world: Results from a global clinical trial.

Circulation Journal 81(11): 1589–1595.

n=38 Japanese people (total global cohort not specified here); 12-month follow-up

Japanese people had no major complications and low, stable pacing thresholds over 12 months. Despite smaller body size and different procedural practices (e.g., anticoagulation, length of stay), their outcomes were comparable to people from outside Japan. Freedom from major complications at 12 months was 100% in Japanese people vs. 96% in the rest of the world (P=0.211).

The limited sample size of the subgroups may restrict the generalisability of the findings to the entire population.

Sperzel J, Burri H, Gras D, et al. (2018)

Primary safety results from the LEADLESS Observational Study.

Europace 20(9): 1491–1497.

n=470 (safety endpoint evaluated in 300 post-pause people); follow-up at discharge, 90 days, 180 days, and every 6 months

Freedom from serious adverse device effects (SADEs) at 6 months was 95% (95% CI: 91 to 97%) in the 300 post-pause cohort, exceeding the predefined performance goal of 86% (P<0.0001). The most common SADEs included cardiac perforation (1%), device dislodgement, and vascular complications (1%). Cardiac perforation and dislodgement decreased significantly following protocol amendments and additional training during the study pause.

Nanostim device is no longer in use due to market withdrawal, limiting current clinical applicability of findings.

Steinwender C, Khelae SK, Garweg C, et al. (2020)

Atrioventricular synchronous pacing using a leadless ventricular pacemaker: Results from the MARVEL 2 study.

JACC: Clinical Electrophysiology 6(1):94–106.

n=75 enrolled; n=40 with sinus rhythm and complete AV block included in the primary efficacy analysis; algorithm performance assessed over a 5 hour download period

In people with sinus rhythm and complete AV block, AV synchronous pacing using the enhanced accelerometer-based algorithm resulted in 70% or more AV synchrony in 95% of participants versus 0% during pacing (p<0.001). Mean AV synchrony rose from 27% to 89%. No pauses or oversensing-induced tachycardia episodes occurred in the full cohort.

Covered in the systematic review included in the main evidence summary.

Steinwender C, Lercher P, Schukro C, et al. (2020)

State of the art: leadless ventricular pacing: A national expert consensus of the Austrian Society of Cardiology.

J Interv Card Electrophysiol 57(1):27–37.

Not a clinical study; no people enrolment or follow-up

Based on pooled evidence, expert opinion, and national practice experience in Austria

This consensus document presents recommendations from a panel of Austrian experts on indications for LP vs TVP, infection management, operator training requirements and technical standards for LP implantation

It emphasises that LPs can be safely implanted with low complication rates if technical and clinical guidance is adhered to.

This was a consensus-based expert opinion rather than a clinical or observational study with original population data or comparative outcomes.

Sultan A, Scheurlen C, Wörmann J et al. (2024)

First long-term outcome data for the Micra VR™ transcatheter pacing system: data from the largest perspective German cohort.

Clinical Research in Cardiology 113(7): 1443–1450.

n=188; mean follow-up of 723.4; SD 598 days

Among 188 people, predominantly with AV block III° in AF (85%), LPs demonstrated excellent long-term safety and performance. No infections or device failures were reported. Electrical parameters remained stable over time despite increased RV pacing demand (from 17% to 87%). Battery status declined as expected (3.2 V to 3 V), consistent with longevity estimates.

Broader real-world registry studies have been covered in main evidence summary.

Tachibana M, Banba K, Matsumoto K, et al. (2020)

The feasibility of leadless pacemaker implantation for superelderly patients.

Pacing Clin Electrophysiol 43(4):374–381.

n=62, aged more than 85 years (TVP group: n=35; LP group: n=27); follow-up duration up to 3 months

Despite a higher proportion of dementia in the LP group (63% versus 37%, p=.04), complication-free rates were similar between LP and TVP groups (87% versus 93%, p=.68). LP implantation had higher initial pacing thresholds (p<.01), but these improved over 3 months. Procedure and hospitalisation durations were shorter in the LP group.

Covered in the systematic review included in the main body evidence.

Tam MTK, Cheng YW, Chan JYS, et al. (2024)

Aveir VR real-world performance and chronic pacing threshold prediction using mapping and fixation electrical data.

Europace 26(3): euae051.

n=123 Aveir VR implant attempts (122 successful, 99%)

n=88 reached 3-month follow-up. Comparison with retrospective cohort of 139 LP people.

3-month PCT correlated with impedance during mapping and tethering (p<0.001), but not with post-fixation PCT (P>0.05). High intraoperative impedance (more than 470 ohms) predicted excellent chronic PCT with 88% sensitivity and 71% specificity. Despite higher initial high PCT rates for Aveir (12%) vs Micra (2%; P=0.004), the 3-month high PCT rates were similar (Aveir 2% vs Micra 3%; P=1.000).

Complication rate was low (1.6%).

Focuses primarily on procedural and electrical performance characteristics (PCT prediction) of the Aveir VR device rather than direct comparative long-term safety or clinical effectiveness outcomes between different device types.

Tan MC, Tan JL, Tay ST, et al. (2023)

A Systematic Review of Short-Term Outcomes of Leadless Pacemaker Implantation After Transvenous Lead Removal of Infected Cardiac Implantable Electronic Device.

American Journal of Cardiology 203: 444–450.

n=253; mean follow-up 11.3; SD 10.6 months

LP implantation after transvenous lead removal (TLR) of infected cardiac devices was feasible and safe, with low complication (4%) and reinfection (less than 1%) rates. The most common infection pathogen was Staphylococcus aureus. Concomitant LP implantation during TLR was performed in 42% of cases. Few short-term complications were noted, including hematoma, femoral AV fistula, and pericardial effusion. 1 LP-related infection occurred during follow-up.

Focused specifically on post-infection TLR scenarios, limiting generalisability to broader LP use cases.

Tjong FVY, Knops RE, Udo EO, et al. (2018)

Leadless pacemaker versus transvenous single-chamber pacemaker therapy: A propensity score-matched analysis.

Heart Rhythm 15(9):1387–1393.

n=440 (LP; n=220; TVP; n=220); median follow-up 800 days

When excluding PM advisory-related events, LPs had fewer complications than TVPs (1% versus 5%, p=.02). However, when including advisory-related complications, LPs had a higher total complication rate (11% versus 5%, p=.063), negating the initial advantage.

Covered in the systematic review included in the main evidence summary.

Togashi D, Sasaki K, Okuyama K, et al. (2023)

Two-year Outcomes of Ventricular-demand Leadless Pacemaker Therapy for Heart Block After Transcatheter Aortic Valve Replacement.

J Innov Card Rhythm Manag 14(6): 5491–5498.

n=39 (17 LPs, 22 TVPs); 2-year follow-up

Post-procedural complication rates were low and similar across groups, people with LPs had significantly higher all-cause mortality (41% versus 5%, p<.01) and more heart failure rehospitalisations (24% versus 0%, p=.01) compared to those with TVPs after TAVR. No significant differences were observed in late device-related adverse events or new-onset AF.

Broader registry study with larger sample size has been prioritised in the main body evidence

Tokavanich N, Machado C, Banga S, et al. (2023)

Implant efficiency and clinical performance of Aveir™ VR and Micra™ VR leadless pacemaker: A multicenter comparative analysis of 67 patients.

Pacing and Clinical Electrophysiology 46(8): 827–832.

n=67; follow-up at 3 and 6 months

Micra VR had significantly shorter electrophysiology lab time (41; SD 12 vs. 55; SD 11.5 min, p=.008) and fluoroscopy time (6.5; SD 2.2 vs. 11.5; SD 4.5 min, p<.001) compared to Aveir VR. Aveir VR showed higher initial pacing thresholds (0.7; SD 0.3 mA vs. 0.5; SD 0.18 mA, p<.001) but matched performance at 3 and 6 months. No significant differences in sensing, impedance, or pacing percentage were observed. Projected battery longevity was significantly greater in the Aveir™ VR group (18.8; SD 4.3 versus 7.7; SD 0.8 years, p<.001). Procedural complications were rare in both groups.

Focused on comparative implant parameters and early performance, not long-term safety or effectiveness outcomes.

Tolosana JM, Guasch E, San Antonio R, et al. (2020)

Very high pacing thresholds during long-term follow-up predicted by a combination of implant pacing threshold and impedance in leadless transcatheter pacemakers.

Journal of Cardiovascular Electrophysiology 31(4):868–874.

n=110 (LP implants from 2014 to 2018); 108 successful implants

Follow-up: up to 48 months (mean 24; SD 16 months)

Only 4% of people developed very high pacing thresholds (VHPT: more than 2 V/0.2 ms). People who developed VHPT had higher implant pacing thresholds (1; SD 0.3 V vs 0.6; SD 0.3 V; p=.003) and lower implant impedance (580; SD 59 ohms vs 837; SD 232 ohms; p=.03).

While valuable for hypothesis generation and identifying predictors, further validation is needed before routine clinical application.

Tonegawa-Kuji R, Kanaoka K, Mori M, et al. (2022)

Mortality and 30-Day Readmission Rates After Inpatient Leadless Pacemaker Implantation: Insights from a Nationwide Readmissions Database.

Canadian Journal of Cardiology 38(11): 1697–1705.

n=137,732 total pacemaker implantations (including 5,986 LP implantations); 30-day follow-up for readmissions

The in-hospital mortality rate for LP implantations was 5%, with an overall in-hospital complication rate of 16%, and a 30-day readmission rate also at 16%. Notably, in-hospital mortality declined from 11% in early 2017 to 4% by late 2019 (P<0.001), and overall complications decreased from 21% to 13% in the same period (P<0.001).

Focused on administrative database outcomes and trends rather than device-specific performance or prospective clinical trial data.

Tam TK, Chan YS, Chan GCP, et al. (2022)

Effect of Low Body Mass Index in Outcome of Micra Leadless Pacemaker Implantation.

Journal of the Hong Kong College of Cardiology 30(2): 43–52.

n=147, who underwent

Follow-up duration extended to 12 months post-implantation.

The composite procedure safety and efficacy outcome was achieved in 93% of people.

The study's single-centre, retrospective design and focus on a specific population subgroup may limit the generalisability of its findings.

Vaidya VR, Dai M, Asirvatham SJ, et al. (2019)

Real-world experience with leadless cardiac pacing.

Pacing Clin Electrophysiol 42(3): 366–373.

n=90 LP recipients (73 Micra, 17 Nanostim) matched 1:1 with 90 TVP recipients; median follow-up 62 days (IQR 28 to 169).

LPs showed comparable safety to TVPs in terms of major (0% versus 1%) and minor (8% versus 3%) complications (p>0.05). LP group had significantly lower rates of device-related revision or extraction (0% versus 5%, p=0.028) and endocarditis (0% versus 3%, p=0.04), and no significant worsening of tricuspid regurgitation (0% versus 19%, p=0.017). Estimated device longevity was longer in the LP group (12 versus 10 years, p<0.0001).

Covered in the systematic review included in the main body evidence.

Valiton V, Graf D, Pruvot E, et al. (2019)

Leadless pacing using the transcatheter pacing system (Micra TPS) in the real world: initial Swiss experience from the Romandie region.

Europace 21(2): 275–280.

n=92; 1-year follow-up

Implantation success rate was high (98%), and pacing thresholds remained low and stable over time (median 0.4 V/0.2 ms). However, serious perioperative adverse events occurred in 7% (n=6), including 1 death, and 3 additional major events (3%) occurred during follow-up (including ventricular tachycardia and device explantation), resulting in an overall 10% major complication rate.

Limited by small sample size and regional data; initial real-world experience only, without comparator arm or long-term evaluation.

Vincent L, Grant J, Peñalver J, et al. (2022)

Early trends in leadless pacemaker implantation: Evaluating nationwide in-hospital outcomes.

Heart Rhythm 19(8): 1334–1342.

Nationally representative cohort: exact sample size not specified in abstract; in-hospital outcomes only.

LP use increased among older and more acutely ill people over time. From 2017 to 2019, LP-related procedural complications decreased significantly (11% to 8%; p<.001), and in-hospital mortality declined (8% to 4%; p<.001). Compared to TVP, LP had fewer procedural complications (9% versus 11%) but higher in-hospital mortality (5% versus 1%; p<.001).

Covered in the systematic review included in the main body evidence.

Wherry K, Stromberg K, Hinnenthal JA, et al. (2020)

Using Medicare Claims to Identify Acute Clinical Events Following Implantation of Leadless Pacemakers.

Pragmatic and Observational Research 11: 19–26.

n=230 dually enrolled people; 30-day follow-up for acute complications

95% agreement in identifying 30-day acute complications between Medicare administrative claims (Micra CED) and physician-adjudicated registry data (Micra PAR). Disagreements in reporting were limited to specific low-frequency complications such as arteriovenous fistula (50%), pulmonary embolism (67%), haemorrhage/hematoma (75%), and deep vein thrombosis (100%). No disagreements occurred in adjudicated event identification.

Focus was on data validation and agreement between administrative claims and registry data rather than direct clinical outcomes or safety/effectiveness of the device.

Xu F, Meng L, Lin H, et al. (2024)

Systematic review of leadless pacemaker.

Acta Cardiologica 79(3): 284–294.

Included 28 studies published between 2015 and 2023, covering a total of 13,129, who underwent LP implantation. Follow-up durations ranged from 3 months to 5 years across included studies.

The review highlights that LPs significantly reduce complications associated with traditional TVPs, especially those related to leads and pacemaker pockets.

More robust systematic reviews have been covered in the main evidence summary.

Yan L, Zhang Y, Liu Q, et al. (2024)

Efficacy and safety of leadless ventricular pacemaker: a single-center retrospective observational study.

Cardiovascular Diagnosis & Therapy 14(2): 878–889.

n=112, who had LP implantation between 2020 and 2023. The average follow-up period was 12.4; SD 3.7 months.

Success rate was 100%. Procedure-related complications occurred in 5% of included people, including 2 cases of pericardial effusion and 3 of vascular access complications. No lead-related or pocket infections were reported. Mean pacing threshold remained stable throughout follow-up (0.5; SD 0.2 V at implant vs. 0.5; SD 0.2 V at final follow-up, P=0.72).

Although informative, this study represents a single-centre retrospective series with limited generalisability, thus was excluded from the main summary table prioritising larger or multicentre datasets.

Zucchelli G, Tolve S, Barletta V, et al. (2021)

Comparison between leadless and transvenous single-chamber pacemaker therapy in a referral centre for lead extraction.

J Interv Card Electrophysiol 61(2):395–404.

n=200 (100 LP, 100 TVP); median follow-up: 12 months

LP implantation was associated with a lower acute complication rate (0% vs 7%, p=0.02) and fewer system revisions (0% vs 6%, p=0.038) compared to TVP. Both groups showed stable electrical performance, but LP demonstrated longer estimated battery longevity. 1 systemic infection occurred in the TVP group.

Covered in systematic review included in the main evidence summary.

Zucchelli G, Barletta V, Della Tommasina V, et al. (2019)

Micra pacemaker implant after cardiac implantable electronic device extraction: feasibility and long-term outcomes.

EP Europace 21(8):1229–1236.

n=83 total (Group 1: 23 post-extraction; Group 2: 60 naïve); median follow-up: 18 months (IQR 1 to 24 months)

LP implantation was feasible and safe in post-TLE people, with no significant differences in fluoroscopy time, delivery success, or electrical performance at implant and 12-month follow-up compared to naïve people. No device-related events occurred during follow-up. Majority of implants achieved non-apical placement (72%) with no significant group differences.

Covered in systematic review included in the main evidence summary.