Mitral Regurgitation Severity After Continuous-Flow LVAD Implantation as ot Associated with Adverse Long-Term Clinical Outcomes

Abstract

Introduction Mitral regurgitation (MR) resulting from a markedly dilated left ventricle (LV) is common in advanced heart failure patients undergoing LV assist device (LVAD) implant. Significant MR post-LVAD therapy can contribute to worsening pulmonary venous hypertension, right ventricular (RV) failure, morbidity and mortality. Our aim was to examine the impact of MR severity on survival outcomes in patients on LVAD support. Methods A single-center retrospective chart review was conducted for any patient with LVAD implant for demographic, clinical, and echocardiographic variables. Post-LVAD MR severity was used to categorize patients into minimal or significant MR groups. Significant (severe) MR was defined by the presence of EROA ≥0.4cm2, regurgitant volume ≥60ml, regurgitant fraction ≥50%, jet >40% of LA, or grade ≥2+. Results 270 patients (mean age 57 ± 12 years) were analyzed. The majority were male (84%), and had non-ischemic cardiomyopathy (60%), bridge-to-transplant LVAD therapy (52%), significant pre-implant MR (75%), and minimal post-LVAD MR (87%). Median survival time after LVAD implant was 5.96 vs 4.74 years among patients with minimal vs significant MR, respectively (p=0.50). No significant difference was seen between groups even after adjusting for age, gender and device indication (hazard ratio 1.49 [95% CI 0.91, 2.24], p=0.119). Median survival time post-LVAD was 4.90 vs 5.41 years among patients with vs without grade ≥1 MR improvement post-LVAD, respectively (p=0.30). Overall, 28 patients (45%) and 75 patients (36%) died in the respective significant and minimal MR cohorts post-LVAD. Conclusions In our cohort, a minority of patients had persistence of significant MR on LVAD support. Survival outcomes on LVAD support or as bridge to heart transplant did not differ based on MR severity post-LVAD implant. Future studies are warranted on the implications of post-LVAD MR severity on hospital readmission burden.