Initiation of Neurohormonal Blockade and Clinical Outcomes in <scp>HeartMate</scp> 3 <scp>LVAD</scp> Recipients During Index Implantation

BACKGROUND: The use of neurohormonal blockade (NB), including beta-blockers, mineralocorticoid receptor antagonists, and renin angiotensin system inhibitors, in patients after left ventricular assist device (LVAD) implantation is associated with improved clinical outcomes. However, its use during and soon after index LVAD implant discharge, a period of potential hemodynamic and laboratory vulnerability, and impact on outcomes in HeartMate 3 (HM3) recipients remain undefined and is the aim of the current study. METHODS: A single-center retrospective analysis was performed of patients undergoing HM3 LVAD implantation and discharged from index implant from January 2015 to December 2021. To align with contemporary management, we included sodium-glucose cotransporter 2 inhibitors in the NB cohort. Patients on and not on any NB after index discharge were compared. Cox proportional hazards modeling was performed to investigate the association between the presence of NB with survival and heart failure (HF) readmission. RESULTS: In total, 273 patients underwent HM3 LVAD implantation during the study period. The average implant age was 58 years, 75% were men, and 78% were Black patients. Of the 273 patients, 138 (50%) had a prescription of at least one NB agent after index discharge. Predictors of NB use included a history of stroke, perioperative renal replacement therapy, and index discharge creatinine level. An index discharge prescription for NB was associated with a lower risk of all-cause mortality at a median follow-up of 3.8 years (age-sex-race adjusted HR 0.63; 95% CI, 0.41-0.98; p = 0.042). The association was attenuated with additional adjustment for the predictors (HR 0.68; 95% CI, 0.43-1.08; p = 0.100). A discharge prescription for NB was not associated with HF readmission. CONCLUSION: While early initiation of NB therapy in HM3 LVAD recipients was associated with a lower risk of mortality, its clinical impact was attenuated after accounting for baseline and perioperative factors. These findings suggest that NB prescription may reflect underlying clinical stability and accordingly, results should be considered hypothesis-generating and warrant prospective evaluation.