Inpatient Outcomes Of Mechanical Circulatory Support Devices and Bridging to Transplantation in Hypertrophic Cardiomyopathy

Objective Understand the outcomes of mechanical circulatory support devices (MCSD) and heart transplantation (HT) in patients with underlying hypertrophic cardiomyopathy (HCM). Introduction HCM can rarely cause severe left ventricular outflow tract obstruction and apical ballooning presenting as cardiogenic shock necessitating the use of mechanical circulatory support devices (MCSD). Data on in-hospital outcomes of HCM patients placed on MCSD and receiving HT is limited. Methods The National Inpatient Sample (2016-2019) was used for the retrospective analysis of patients hospitalized for MCSD and HT using ICD-10 codes. These patients were divided into two cohorts, with and without HCM, and compared in terms of in-hospital mortality, trends in mortality rates, hospitalization costs and mean length of stay. Results Among 254170 patients hospitalized for MCSD and HT, 12,000 patients had underlying HCM. Underlying HCM was associated with increased odds of mortality in patients receiving left ventricular assist devices (LVAD) (OR 3.06, 95% CI 1.18-7.93, p =0.02) and short-term MCSD (OR 1.8, CI 1.29-2.5, p<0.001. HCM was not associated with increased mortality in patients hospitalized for HT (OR 1.05, CI 0.42-2.6, p =0.9). Patients with HCM undergoing MCSD and HT had a longer mean length of stay (26.6 vs 14.4 days, p<0.0001), and higher mean hospitalization charges ($977797 vs $497590, p<0.0001) as compared to non-HCM patients. Conclusion Underlying HCM is associated with increased in-hospital mortality in patients undergoing LVAD and short-term MCSD placement. Further prospective studies are required to expand our understanding of prognosis of HCM in patients undergoing MCSD and establish management guidelines.