Persistent mitral regurgitation after left ventricular assist device: a clinical conundrum

Persistent mitral valve regurgitation (MR) after continuous flow left ventricular assist device implantation (cfLVAD) is associated with pulmonary hypertension and right ventricular failure with variable effects on survival across published studies. The aim of this study is to determine the incidence and predictors of persistent MR at 6-month follow-up after cfLVAD implantation and its impact on survival, haemodynamics, right ventricular function, and morbidity.

We performed a retrospective review of all adult cfLVAD recipients from January 2012 to June 2017 at a single tertiary university hospital with follow-up until April 2019. Primary outcome was to compare survival between patients with no-to-mild compared with persistent moderate-to-severe MR at 6 months. Secondary outcomes included right heart failure (RHF), length of stay, re-hospitalizations, and composite of death, transplant, and pump exchange during the length of follow-up. Final analytic sample was 111 patients. The incidence of persistent moderate or severe MR at 6 months was 26%. Significant predictors of persistent MR at 6 months were left atrium dimension and volume. The group with persistent moderate-to-severe MR at 6 months had higher incidence of RHF at 6 months (45% vs. 25%, P = 0.04). There was no difference in survival at 1 year between the groups (no-to-mild MR 85.5%, moderate-to-severe MR 87.9%, Wilcoxon P-value = 0.63). There was no difference in re-hospitalizations, length of stay, composite of death, transplant, or pump exchange during the length of follow-up between the comparison groups.

Persistent moderate-to-severe MR after cfLVAD implantation is present in one fourth of patients and is associated with increased incidence of RHF, higher mean pulmonary pressure, and pulmonary capillary wedge pressure with no effect on 1 year survival. Increased left atrium size was associated with persistent moderate-to-severe MR at 6 months.