PO-05-025 LONGER TERM OUTCOMES IN PATIENTS PRECLUDED FOR TRANSVENOUS PACEMAKER IMPLANTATION: EXPERIENCE WITH THE MICRA VR TRANSCATHETER PACEMAKER

Abstract

The Micra leadless pacemaker is a safe and effective alternative to transvenous pacemakers (TVP). However, longer-term safety and mortality in patients precluded for TVP is not well characterized. To assess long-term safety and mortality among patients implanted with a Micra leadless pacemaker who are precluded for TVP. Micra VR patients from the Post-Approval Registry (PAR) and Micra VR Acute Performance European and Middle Eastern (MAP EMEA) registry were divided into groups based upon whether the implanting physician considered the patient to be precluded from receiving a transvenous pacing system. All-cause mortality through 5-years post-implant was compared between Micra groups and patients receiving a single-chamber transvenous pacemaker (SC-TVP) from the Medtronic product surveillance registry using univariate and propensity weighted Cox models. Among 2,735 Micra patients, 841 (30.7%) were deemed precluded from SC-TVP implant primarily due to history of CIED infection or venous access issues. Precluded patients were younger (74.2 vs 76.6 years), more likely to have a prior CIED implant (41.7% vs 7.6%), more likely to require dialysis (21.5% vs 3.0%), and more likely to have congestive heart failure (18.8% vs 11.5%). Five-year all-cause mortality was higher in precluded Micra patients compared to SC-TVP patients (HR: 1.93, 95% CI: 1.56 – 2.40, P<0.001); however, there was no significant difference in mortality when comparing non-precluded Micra patients and SC-TVP patients (HR: 0.95, 95% CI: 0.77 – 1.16, P=0.59; Figure). Major complication rates at 5-years related to the Micra VR system or procedure were 5.2% for precluded and 4.1% non-precluded Micra patients (P=0.170). Pericardial effusion rates regardless of severity were 1.2% for precluded and 0.7% for non-precluded patients (P=0.27). All-cause mortality risk through 5 years was highest for patients who were precluded from receiving SC-TVP, despite no difference in system or procedure related major complication rates among precluded and non-precluded Micra patients. However, all-cause mortality risk was similar for non-precluded Micra patients and SC-TVP patients. Preclusion for TVP should be considered when comparing outcomes between Micra and TVP patients.