LONG-TERM SURVIVAL IMPACT OF CONCOMITANT MITRAL VALVE INTERVENTION IN PATIENTS WITH SEVERE AORTIC STENOSIS AND FUNCTIONAL MITRAL REGURGITATION UNDERGOING AORTIC VALVE REPLACEMENT

Abstract

Whether patients with severe aortic stenosis (AS) and significant (≥moderate) functional mitral regurgitation (FMR) should undergo isolated aortic valve replacement (AVR) or double aortic and mitral valve replacement (DVR) remains controversial. Accordingly, we sought to compare their perioperative and long-term outcomes following AVR or DVR. Among patients undergoing isolated AVR, we also sought to determine the impact of significant residual MR on long-term survival. Data prospectively collected from 736 consecutive patients with severe AS and FMR were retrospectively analyzed, and their echocardiograms reviewed by a single blinded cardiologist. Patients with organic or ischemic MR (previous or concomitant CABG/PCI), previous AVR or more-than-mild aortic regurgitation were excluded, resulting in 74 patients constituting our study population. Of these, 19 patients had a DVR, and 55 patients an isolated AVR. Among patients undergoing DVR, 14 (74%) underwent mitral valve replacement and 5 (26%) underwent mitral valve repair. Their pre-operative characteristics, post-operative complications and age-adjusted survival over time were compared. Patients from the isolated AVR group were older and had milder FMR (87% moderate and 13% severe MR vs 12% moderate and 88% severe MR in the DVR group, p < 0.0001). Patients undergoing DVR required more post-operative blood transfusions (84% vs 38%, p=0.0005) and had a longer hospital stay (9.9 vs 7.0 days, p=0.01), but there were no differences in perioperative mortality (5.3% vs 6.7%, p=0.83) or other complications compared with patients undergoing isolated AVR. After adjustment for age, there was no significant difference in survival over time between the two groups (p=0.26, see figure). However, patients in the isolated AVR group whose MR improved following surgery (60%) had significantly increased long-term survival compared with patients in the group with significant residual MR (40%) (p=0.03). In patients with severe AS and significant FMR, DVR is not associated with significant differences in perioperative mortality, perioperative complications and long-term age-adjusted survival. In patients undergoing isolated AVR, nearly a third remain with significant residual MR at long-term follow up, and persistence of significant residual MR after surgery is associated with significantly lower long-term survival. This suggests that in patients with significant FMR and severe AS, a concomitant mitral intervention should be strongly considered, or a staged approach contemplated in the absence of MR improvement after the initial surgery.