Objective: Aortic insufficiency (AI) can lead to left ventricular (LV) remodeling characterized by dilation and increased LV mass. This remodeling can cause altered mitral valve coaptation and functional mitral regurgitation (FMR). While there is growing evidence that aortic valve replacement (AVR) for aortic stenosis promotes sufficient ventricular reverse remodeling that FMR improves or resolves, this effect is not well characterized for patients with AI.
Methods: All cases of AVR for AI that were performed at a single center between January 2003 and December 2015 were reviewed. Cases with any concomitant procedures, any degree of aortic stenosis, any evidence of ischemic etiology, absence of mitral regurgitation, or significant primary mitral pathology were excluded from analysis. The primary outcome was change in FMR after isolated AVR. Secondary outcomes included change in LV ejection fraction (EF), left atrial (LA) dimension, and change in end-diastolic and –systolic LV dimensions. Two-tailed paired t-test was used to evaluate for difference between the two time points.
Results: Over the course of 13.4 years, 31 cases of isolated aortic valve replacement for pure aortic insufficiency with concurrent functional mitral regurgitation were identified. 54.8% (17/31) of cases had some evidence of bacteremia or aortic vegetations at time of surgery, with 41.9% (13/31) of cases completed urgently. Postoperatively, FMR was improved in 74.2% (23/31) of the patients, and decreased by a mean 1.0 ± 0.8 grades (1.6 ± 0.8 vs 0.6 ± 0.7, p < 0.001). There was no significant change in LV EF (50.5 ± 13.4 vs. 50.2 ± 12.9, p = 0.892) or LA dimension (42.5 ± 7.2 vs 40.7 ± 5.9, p = 0.341), but there were significant reductions in the dimension of the LV at end-diastole (56.7 ± 7.1 vs 47.7 ± 8.5, p < 0.001) and end-systole (38.5 ± 9.7 vs 34.0 ± 8.3, p = 0.011).
Conclusions: Significant reduction in ventricular size and subsequent improvement in functional mitral regurgitation is expected after isolated aortic valve replacement for pure aortic insufficiency.