Impact of aortic valve replacement for severe aortic stenosis on organic and functional mitral regurgitation

Aims Concurrent mitral regurgitation (MR) influences treatment considerations in patients with severe aortic stenosis (sAS). Limited information exists regarding haemodynamic effects of sAS on MR severity and outcome of these patients. We assessed the impact of aortic valve replacement (AVR) on MR according to mechanism in patients with sAS and MR. Methods and results In patients with sAS who received surgical or transcatheter AVR from 2008 to 2017, those with effective mitral regurgitant orifice area (ERO) ≥ 10 mm2 prior to AVR were evaluated. The change in MR after AVR was considered significant when there was at least one grade difference. We compared the all‐cause mortality of patients with and without improvement in MR. Of 234 patients with sAS and MR (age 80 ± 9 years, 52% male, ERO 19 ± 7 mm2), organic and functional MR were present in 166 (71%) and 68 (29%), respectively. MR improved in 136 (58%); improvement occurred with similar frequency in organic versus functional MR (59% and 57%, P = 0.88). Associated determinants were absence of atrial fibrillation in organic MR [odds ratio (OR) 2.09, 95% confidence interval (CI) 1.00–4.37; P = 0.049] and indexed aortic valve area (iAVA) ≤ 0.40 cm2 in functional MR (OR 3.28, 95% CI 1.13–9.47; P = 0.028). In the overall cohort, mitral annulus diameter