Incidence and Clinical Significance of Aortic Regurgitation in HeartMate 3 Continuous Flow Left Ventricular Assist Device Recipients: An Analysis from the Momentum 3 Trial Portfolio

Abstract

<h3>Purpose</h3> Aortic Regurgitation (AR) is a significant complication following LVAD implantation but has not been adequately studied in patients with the HeartMate 3 (HM3) LVAD. In this trial level analysis of the MOMENTUM 3 pivotal trial (M3 PT) and Continued Access Protocol (M3 CAP), we plan to assess the incidence, predictors and clinical outcomes of AR in HM3 implants. <h3>Methods</h3> AR incidence at 2-years was analyzed in the randomized M3 PT and validated in the first 500 implanted patients of the M3 CAP. Patients with concomitant or prior aortic valve surgery or without baseline or post-implant echocardiograms were excluded from this analysis. Each site provided qualitative assessment of AR severity by echocardiography. Significant AR was defined as moderate or severe grades of AR. Comprehensive evaluation of predictors of development of AR, effect of this complication on hospitalizations, major adverse events (including hemocompatibility and non-hemocompatibility related events), functional capacity and QOL will be completed by February 2021. <h3>Endpoints</h3> Of 1028 patients enrolled in the M3 PT, 918 were included in this analysis (HM3=465, HMII=453). At 2-years of LVAD support, fewer HM3 (5.6% (26/465)) than HMII (11.5% (52/453)) patients demonstrated clinically significant AR (HR 0.35, 95% CI 0.20 - 0.59, p<0.01). (Figure) Of 455 patients analyzed from the first 500 implanted M3 CAP patients, the rate of clinically significant AR was 5.9% (27/455), consistent with the M3 PT (P=0.3). Due to lower rates of AR in the HM3 than with previous devices, we plan to add 500 patients from the M3 CAP (for a total of over 1500 HM3 implants) to provide sufficient power to discern the predictors and clinical impact of AR by February 2021. This analysis will represent the first and largest outcomes-based evaluation performed within a prospective clinical trial portfolio. (M3 PT: NCT02224755; M3 CAP: NCT02892955; Funded by Abbott).