Comparing leadless and conventional pacemakers for heart rhythm issues

The Leadless AV Versus DDD Pacing Study: A Randomized Controlled Single-center Trial on Leadless Versus Conventional Cardiac Dual-chamber Pacing

PHASE4 · Insel Gruppe AG, University Hospital Bern · NCT05498376

This study tests if a new leadless pacemaker can help older patients with heart rhythm problems just as well as traditional pacemakers, but with fewer complications.

Quick facts

PhasePHASE4
Study typeInterventional
Enrollment100 (estimated)
Ages70 Years and up
SexAll
SponsorInsel Gruppe AG, University Hospital Bern (other)
Locations1 site (Bern)
Trial IDNCT05498376 on ClinicalTrials.gov

What this trial studies

This clinical trial evaluates the effectiveness of a leadless pacemaker system, Micra AV, compared to traditional dual-chamber pacemakers in patients aged 70 and older with atrioventricular block. The study aims to determine if the leadless system can provide similar or improved heart rhythm management without the complications associated with traditional leads. Participants will be monitored for outcomes related to heart function and device performance. The trial includes patients who are eligible for either type of pacemaker and will assess the safety and efficacy of the leadless option.

Who should consider this trial

Good fit: Ideal candidates are patients aged 70 and older who require a new pacemaker due to intermittent or permanent atrioventricular block.

Not a fit: Patients with permanent atrial fibrillation, significant heart failure, or those requiring specific pacing not compatible with the leadless device may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to safer and more effective heart rhythm management for elderly patients with bradyarrhythmias.

How similar studies have performed: Previous studies have shown promising results with leadless pacemakers, indicating potential for success with this newer version.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Patients (≥70y) undergoing a de-novo pacemaker implantation due to intermittent or permanent AV block, qualifying for a conventional or leadless pacemaker
* Written informed consent

Exclusion Criteria:

* Permanent atrial fibrillation or atrial standstill
* Evidence of sinus node disease and need for right atrial pacing (not possible with Micra AV)
* LVEF \<50% and permanent high-degree or total AVB (requiring CRT/His-Bundle/CSP pacing)
* Preoperative E/A ratio \>1.5 in the echocardiography
* Any co-existing ICD indications (no leadless ICD systems available)
* Hemodialysis
* Presence of a mechanical tricuspid valve prosthesis
* Unwilling or unable to comply fully with study procedures and follow-up

Where this trial is running

Bern

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Cardiac Pacemaker, Arrhythmias, Cardiac, Heart Diseases, Cardiovascular Diseases, Leadless pacemaker, Atrioventricular conduction block, Bradyarrhythmias, Micra

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.