Hospitalization Patterns and Impact of a Magnetically-Levitated Left Ventricular Assist Device in the MOMENTUM 3 Trial

Background: In the MOMENTUM 3 (Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3) pivotal trial, the HeartMate 3 (HM3) fully magnetically levitated left ventricular assist device (LVAD) demonstrated superiority over the axial-flow HeartMate II (HMII) LVAD. The patterns and predictors of hospitalizations with the HM3 LVAD have not been characterized.

Objectives: This study sought to determine causes, predictors, and impact of hospitalizations during LVAD support.

Methods: Patients discharged after LVAD implantation were analyzed. In the pivotal trial, 485 recipients of HM3 were compared with 471 recipients of HMII. The pivotal trial HM3 group was also compared to 949 recipients of HM3 in the postapproval phase within the trial portfolio. Predictors of cause-specific rehospitalization were analyzed.

Results: The rates of rehospitalization were lower with HM3 LVAD than with HMII LVAD in the pivotal trial (225.7 vs 246.4 events per 100 patient-years; P < 0.05). Overall, rehospitalization rates and duration were similar in the HM3 postapproval phase and pivotal trial but prolonged hospitalizations (>7 days) were less frequent (rate ratio: 0.90 [95% CI: 0.80-0.98]; P < 0.05). In HM3 recipients, the most frequent causes of rehospitalization included infection, heart failure (HF)-related events, and bleeding. First rehospitalization caused by HF-related event versus other causes was associated with reduced survival (HR: 2.2 [95% CI: 1.3-3.9]; P = 0.0014). Male sex, non-White race, presence of cardiac resynchronization therapy/implantable cardioverter-defibrillator, obesity, higher right atrial pressure, smaller LV size, longer duration of index hospitalization, and lower estimated glomerular filtration rate at index discharge predicted HF hospitalizations.

Conclusions: Contemporary support with the HM3 fully magnetically levitated LVAD is associated with a lower hospitalization burden than with prior pumps; however, rehospitalizations for infection, HF, and bleeding remain important challenges for progress in the patient journey. (MOMENTUM 3 IDE Clinical Study, NCT02224755; MOMENTUM 3 Continued Access Protocol [MOMENTUM 3 CAP], NCT02892955).