TITLE:
The Structural Impact of Aortic Valve Replacement on Mitral Regurgitation
AUTHORS:
Conor F. Hynes, Dominic A. Emerson, Michael D. Greenberg, Federico E. Mordini, Gregory D. Trachiotis
KEYWORDS:
Aortic Valve, Replacement, Cardiac Anatomy/Pathologic Anatomy, Mitral Regurgitation
JOURNAL NAME:
World Journal of Cardiovascular Surgery,
Vol.6 No.2,
February
23,
2016
ABSTRACT: Background: Structural changes to the mitral annulus occur following aortic valve replacement
(AVR) for severe aortic stenosis which may influence functional mitral regurgitation (MR). Methods:
A retrospective review of 44 patients who underwent open AVR for aortic stenosis at a single
center from 2010-2013 was performed. Patients undergoing concomitant aortic root surgery
or with severe MR were excluded. MR was evaluated with preoperative and postoperative transthoracic
echocardiograms. Univariate and multivariable analyses were performed to assess for
factors associated with postoperative MR improvement and worsening. Results: Prior to AVR,
none had severe MR, 5% (2 patients) had moderate, 9% (4 patients) mild-to-moderate, 46% (20
patients) mild, and 23% (9 patients) trace MR. Of patients with pre-operative MR, 44% (16 patients)
experienced improvement of MR. Six patients had worsening of MR and the remaining 22
patients had no change. Cases of more severe MR were more likely to improve compared with mild
or trace MR (P = 0.04). MR worsening was significantly more likely in patients with bicuspid aortic
valves (83% vs. 24%; P = 0.004), and with larger aortic annulus diameters (P = 0.03). MR worsening
was less frequent in cases of mitral annular calcification (0% vs 42%; P = 0.04) and left atrial
enlargement (17% vs 65%; P = 0.03). Logistic regression analysis revealed negative predictors for
MR improvement were mitral annular calcification (P = 0.04) and larger aortic annulus diastolic
diameter (P = 0.05). Conclusion: Structural factors such as aortic annular size, mitral annular calcification
and valve morphology may impact MR following AVR and should be investigated further
as potential targets of surgical therapy.