Recovery of RV Function Determines Outcomes of Extracorporeal Biventricular Support for Acute Biventricular Failure

Purpose Mechanical circulatory support for acute biventricular failure is challenging. Given that durable VAD is available only for LV support as bridge-to-transplantation in Japan, the treatment options for this pathology are limited to extracorporeal biventricular assist device (BiVAD) support first, which can be subsequently upgraded to durable LVAD in cases having recovery of RV function and transplant candidacy. The purpose of this study was to review the outcomes of extracorporeal BiVAD and to explore factors associated with the outcomes. Methods This study enrolled an institutional consecutive series of 39 cases who underwent extracorporeal BiVADs implantation for acute biventricular failure between April 2014 and October 2020. The etiological diagnosis was myocarditis in 27 cases, acute MI in 6 cases, and dilated cardiomyopathy (DCM) in 6 cases. The cases were assigned into the two groups according to the BiVAD support less than 7 days (n=18, Short group) or 7 days or more (n=21, Long group). The Long group consisted of 6 cases of acute MI (100%), 13 cases (48%) of myocarditis, two cases of DCM (33%). Results There was no case who deceased within 7 days after BiVAD implantation. In the Short group, extracorporeal LVAD was weaned-off in 11 cases (61%) or upgraded to durable LVAD in 6 cases after withdrawal of RV support within 7 days. The remaining one case deceased under extracorporeal LVAD. In the Long group, RV support was discontinued in 10 cases in the median support of 60 days (IQR; 24.2-76.8), while two cases were on BiVAD support at October 2020. The remaining nine cases (43%) deceased under BiVAD support in-hospital. Survival and VAD-free survival at 1 year were 79% and 56% in the Short group versus 48% and 20% in the Long group, respectively. Conclusion Outcomes of extracorporeal BiVAD support for acute biventricular failure were dependent on recovery of RV function. Targeting approach for RV function would be warranted for poor biventricular function.