BackgroundSevere aortic regurgitation (AR) and mitral regurgitation (MR) can lead to left ventricular (LV) systolic dysfunction; however, there are limited data about recovery of LV after surgery for AR or MR. Little is known to guide the management of combined AR and MR (mixed valvular heart disease [VHD]). This study is sought to investigate the predictors of postoperative LV function recovery in left-sided regurgitant VHD with reduced left ventricular ejection fraction (LVEF), especially for mixed VHD.MethodsFrom 2010 to 2020, 2053 adult patients underwent aortic or mitral valve surgery at our center. The patients with valvular stenosis, infective endocarditis, concomitant revascularization, and preoperative LVEF ≥40 % were excluded. A total of 127 patients were included in this study: 22 patients with predominant AR (AR group), 64 with predominant MR (MR group), and 41 with combined AR and MR (AMR group).ResultsThe mean preoperative LVEF was 32.4 %, 30.7 %, and 30.2 % (p = 0.44) in the AR, MR, and AMR groups, respectively. The AR group was more likely to have postoperative LVEF recovery. The cut-point of left ventricular end-systolic diameter (LVESD) for better recovery was 49 mm for the MR group and 58 mm for the AMR group.ConclusionLV dysfunction due to combined AR and MR has similar remodeling reserve as AR, and better recoverability than MR. Thus, double-valve surgery is recommended before the LVESD is > 58 mm.