Micra vs Aveir leadless peacemakers: which is the best option? Experience implantation and follow-up in a medium-volume centre in Spain

As the population ages, the number of pacemaker implantations is increasing. To avoid complications associated with traditional pacemakers, leadless pacemakers have been developed as a safe and effective alternative pacing therapy. In 2023 in Europe was introduced a novel leadless stimulation system Aveir (Abbott) as an alternative to the Micra (Medtronic) system, which has been in use since 2016.

To compare safety, effectiveness, and electrical parameters at implantation and during follow-up between Micra and Aveir at real-word performance.

Single-centre, observational, prospective, analytical study in Spain. We consecutively enrolled all patients available receiving Micra and Aveir between March 2022 and October 2024. The clinical variables and characteristics related to pre- or implantation procedure were collected, as well as safety (acute or subacute/chronic complications), and post-implantation electrical parameters at the time of procedure and in two posterior visits: one-month post-implantation, and at three-month follow-up. Statistical analysis was conducted using the SPSS 28.0 version software.

53 patients (pts) undergone leadless pacemaker implantation, 34 Micra-Medtronic AV and VR and 19 patients who had received the Aveir-Abbott VR. The majority were of advanced age (mean 73.79) and the electrocardiographic indication was slow/blocked atrial fibrillation (84,2%). Baseline characteristics and clinical variables related to procedure were comparable and are illustrated in table 1.

Implantation was achieved in 100% (19) of patients in the Aveir group with one Micra system failure (NS). A single device release was lower in the Aveir group (68.4% vs. 79.4%; p = 0.38) and the number of releases needed was similar (1.4 vs. 1.38; p = 0.24). Furthermore, procedure times (in minutes) (51.96 vs. 49.13; p = 0.29) and escopia (13.99 vs. 10; p = 0.3) were analogous. Two patients (10.5%) experienced complications: a device dislodge and AV block during implantation in Aveir group. The electrical parameters at implantation, first and third month were equivalent. Following implantation, the R wave was lower in the Aveir group (7,647[±3,32] vs 11,36 [±4,77] p=0,04) and a statistically significant higher threshold was maintained during the first visit (0,6 [±0,16 vs 0,46 [±0,23] p=0,05) but not in three-month follow-up, as illustrated in Figure 1. It was remarkable that within 53.5% of pacing, the estimated longevity at 3 months was 18,25 years in the Aveir group.

The Aveir device is an effective and safe alternative with electrical parameters comparable to Micra in terms of monitoring. Larger sample studies are needed to confirm our findings.Table 1.

Baseline characteristics