SPC365

Comparative Real-World Performance of First- and Second-Generation of Micra AV Leadless Pacemaker: Insights from a Two-Center Experience

Session: Sessão de Posters 29 - Pacing sem elétrodos e inovação em dispositivos
Speaker: Margarida Câmara Farinha

Congress: CPC 2026
Topic: C. Arrhythmias and Device Therapy
Theme: 09. Device Therapy
Subtheme: 09.1 Antibradycardia Pacing
Session Type: Posters Eletrónicos
FP Number: ---
Authors: Margarida Câmara Farinha; Fernando Nascimento Ferreira; Fabiana Duarte; João Pereira; Sónia Oliveira; Bruno Valente; Susana Covas; Ana Lousinha; Pedro Silva Cunha; André Viveiros Monteiro; Miguel Pacheco; Mário Oliveira

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:&quot;Times New Roman&quot;,serif"><u><span style="background-color:white"><span style="font-family:&quot;Arial&quot;,sans-serif"><span style="color:#212121">Background:</span></span></span></u><span style="background-color:white"><span style="font-family:&quot;Arial&quot;,sans-serif"><span style="color:#212121"> Micra AV (Medtronic) was the first-generation leadless pacemaker (LP) capable of ventricular pacing and </span></span></span><span style="font-family:&quot;Arial&quot;,sans-serif">mechanical atrial sensing <span style="background-color:white"><span style="color:#212121">(VDD mode), </span></span>but with <span style="background-color:white"><span style="color:#212121">a high variability in AV synchrony (AVS) reported. A second generation, Micra AV2, is now available, promising higher automatic tracking capability and longer battery life. However, real-world data of AVS reliability and device </span></span>long-term performance<span style="background-color:white"><span style="color:#212121"> is scarce. </span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:&quot;Times New Roman&quot;,serif"><u><span style="font-family:&quot;Arial&quot;,sans-serif">Purpose:</span></u><span style="font-family:&quot;Arial&quot;,sans-serif"> <span style="background-color:white"><span style="color:#212121">We sought to access </span></span><span style="color:#212121">real-world effectiveness of Micra AV pacemakers, comparing both device generations regarding <span style="background-color:white">electrical performance, atrioventricular tracking, reprogramming requirements and battery status.</span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:&quot;Times New Roman&quot;,serif"><u><span style="font-family:&quot;Arial&quot;,sans-serif">Methods:</span></u><span style="font-family:&quot;Arial&quot;,sans-serif"> <span style="background-color:white"><span style="color:#212121">This was a two-center analysis including consecutive patients implanted with a Micra AV for atrioventricular block, screened and assessed before discharge and during follow-up (1- and 6- month post-implant). Patients were divided in first- (Micra AV1) and second-generation (Micra AV2) devices and compared regarding </span></span><span style="color:#212121">AVS and atrial mechanical sensed-ventricular pacing (AM-VP), </span>ventricular pacing burden without AVS (%VP-only), reprogramming needs <span style="color:#212121">and battery longevity.</span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:&quot;Times New Roman&quot;,serif"><u><span style="font-family:&quot;Arial&quot;,sans-serif">Results:</span></u><span style="font-family:&quot;Arial&quot;,sans-serif"> Forty-two patients were included (Micra AV1 n=28; Micra AV2 n=14). Baseline characteristics were comparable, with similar distribution of major cardiovascular comorbidities. <span style="background-color:white"><span style="color:#212121">AVS was better in </span></span>Micra AV2 group with significantly higher AM-VP at all timepoints (pre-discharge: 3.1% vs 47.8%, p=0.02; 1 month: 30.9% vs 72.4%, p=0.03; 6 months: 13.6% vs 76.2%, p=0.008). In contrast, individualized reprogramming was more frequent in Micra AV1 patients (61.3% vs 21.4%, p=0.02). This was even more evident in patients with higher ventricular pacing burden (&gt;20%). In this subgroup, Micra AV2 maintained markedly better atrial mechanical synchrony throughout follow-up (pre-discharge: 1.9% vs 64.6%, p=0.028;1 month: 5.1% vs 76.6%; p=0.049; and 6 months: 5.9% vs 79% p=0.035) and less reprograming (77.8% vs 22.2%, p=0.033). </span></span></span></p>

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="font-family:&quot;Arial&quot;,sans-serif">Regarding <span style="background-color:white"><span style="color:#212121">battery parameters, Micra AV2 group had better projected longevity </span></span>in the overall cohort (battery voltage 2.58V vs 2.56V; p=0.001) and in high-burden patients (battery voltage 2.58V vs 2.56V; p=0.025).</span></span></span></p>

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:&quot;Times New Roman&quot;,serif"><u><span style="font-family:&quot;Arial&quot;,sans-serif">Conclusions:</span></u><span style="font-family:&quot;Arial&quot;,sans-serif"> <span style="background-color:white"><span style="color:#212121">Micra AV2 pacemakers </span></span>demonstrated enhanced atrial-mechanical tracking, reduced need for reprogramming and superior battery estimates compared to first generation devices. These findings support improved device efficiency in real-world practice of Micra AV2.</span></span></span></p>