Impact of age, sex, therapeutic intent, race and severity of advanced heart failure on short-term principal outcomes in the MOMENTUM 3 trial

Background Primary outcomes analysis of the Multicenter Study of MagLev Technology in Patients Undergoing MCS Therapy With HeartMate 3 (MOMENTUM 3) trial short-term cohort demonstrated a higher survival rate free of debilitating stroke and reoperation to replace/remove the device (primary end-point) in patients receiving the HeartMate 3 (HM3) compared with the HeartMate (HMII). In this study we sought to evaluate the individual and interactive effects of pre-specified patient subgroups (age, sex, race, therapeutic intent [bridge to transplant/bridge to candidacy/destination therapy] and severity of illness) on primary end-point outcomes in MOMENTUM 3 patients implanted with HM3 and HMII devices. Methods Cox proportional hazard models were used to analyze patients enrolled in the “as-treated cohort” (n = 289) of the MOMENTUM 3 trial to: (1) determine interaction of various subgroups on primary end-point outcomes; and (2) identify independent variables associated with primary end-point success. Results Baseline characteristics were well balanced among HM3 (n = 151) and HMII (n = 138) cohorts. No significant interaction between the sub-groups on primary end-point outcomes was observed. Cox multivariable modeling identified age (≤65 years vs >65 years, hazard ratio 0.42 [95% confidence interval 0.22 to 0.78], p = 0.006]) and pump type (HM3 vs HMII, hazard ratio 0.53 [95% confidence interval 0.30 to 0.96], p = 0.034) to be independent predictors of primary outcomes success. After adjusting for age, no significant impact of sex, race, therapeutic intent and INTERMACS profiles on primary outcomes were observed. Conclusions This analysis of MOMENTUM 3 suggests that younger age (≤65 years) at implant and pump choice are associated with a greater likelihood of primary end-point success. These findings further suggest that characterization of therapeutic intent into discrete bridge-to-transplant and destination therapy categories offers no clear clinical advantage, and should ideally be abandoned.