Abstract 11583: Impact of Micra Pacemaker Implantation on Echocardiographic Parameters: A Multi-Center Analysis

Introduction: Studies on leadless pacemakers (LP) are very limited and they often fail to reflect real population outcomes. Hypothesis: We sought to evaluate the effect of leadless pacemaker implantation on the echocardiographic parameters including ventricular function and valvular competence. Methods: A retrospective review including 162 patients (81 Micra Leadless pacemaker implant and 81 dual-chamber transvenous pacemakers) from 3 centers were included. Follow-up clinical, echocardiographic, and pacing characteristics were obtained over a median of 14+/-2 months. Results: baseline demographics and clinical characteristics were comparable between the 2 groups including age (78.6+/-9.9, Range 35-95) and gender (49 males, 69.5%). Compared to conventional pacemakers, LP patients had worsening tricuspid regurgitation noted on follow-up echo in 59.3% of patients compared to baseline(P<0.001). This difference was independent of the RV pacing percentage and device location. In addition, LP implantation resulted in a reduction of RV function (P=0.003) and left ventricular ejection fraction (P=0.03). The RV Pacing burden in LP patient patients was not associated with a change in LVEF during the follow-up period (95% CI -0.24, 0.20, p = 0.846). Conclusions: LP therapy is associated with worsening tricuspid valve regurgitation and biventricular dysfunction over a mean 1 year of follow-up. Additional prospective randomized studies are warranted to further evaluate these findings.