The combined mitral stenosis (MS) and aortic regurgitation (AR) impose opposite loading conditions on the left ventricle. Physiologically, the relief of MS may increase the severity of AR.

Participants were Filipinos 19 years or older, admitted because of severe MS with mild to moderate AR. The outcome of percutaneous transmitral commissurotomy (PTMC) was divided into two groups: (1) significant AR that included the increase in severity of AR: mild to moderate/severe or moderate to severe AR, and (2) the insignificant AR group, which included any decrease in the severity of AR: moderate to mild or persistence of mild or moderate AR. These groups were compared from baseline, 24 hours, 1 month, and 6 months using the same echocardiographic parameters. The numerical data between significant and insignificant tricuspid regurgitation were compared using nonparametric Mann-Whitney U test and categorical data using the χ2 test.

A total of 43 participants were analyzed. At 24 hours post-PTMC, the significant AR group had significantly lower left ventricular end-diastolic dimension (3.83 vs 4.5, P = 0.008), left ventricular end-systolic dimension (2.33 vs 2.97, P = 0.017), right ventricular fraction area change (38.6 vs 48.7, P = 0.025), and left ventricular outflow tract (1.66 vs 2.02, P = 0.020) and higher systolic pulmonary arterial pressure (57 vs 32.4, P = 0.008). At 1 and 6 months, there were no significant differences in echocardiographic parameters between the significant and insignificant AR groups' left ventricular end-diastolic dimension (4.58 vs 4.5, 4.64 vs 4.57), left ventricular end-systolic dimension (3.1 vs 2.9, 2.9 vs 2.91), and systolic pulmonary arterial pressure (28 vs 34.7, 33.8 vs 32.4). Those with significant AR had a higher mean Wilkin score (mean, 10; P = 0.007) and subvalvular thickening (mean, 2.6; P = 0.005).

On short-term follow-up, the presence of mild to moderate AR before PTMC does not lead to severe AR. The outcomes regardless of the group showed a good functional class and no significant echocardiographic differences when compared.