Incidence and Predictors of Aggravation of Mitral Regurgitation After Atrial Septal Defect Closure.

BACKGROUND

The association between atrial septal defect (ASD) and mitral regurgitation (MR) is well known. However, data about the predictors of changes in MR after ASD closure are limited. The purpose of this study was to clarify the chronological changes in MR after ASD closure and the predictors of aggravation of MR.

METHODS

In this single-center cohort study, we retrospectively investigated 129 consecutive adult patients (mean age, 53 ± 14 years) who underwent surgical ASD closure between 1987 and 2014. The MR grade was qualitatively classified as none, mild, moderate, or severe by echocardiography. Aggravation of MR was defined as an increase by two or more grades after ASD closure. Clinical factors and echocardiographic and catheterization data were evaluated.

RESULTS

The mean follow-up period was 77 months. Aggravation of MR after ASD closure occurred in 16 patients (12%). The rate of perioperative atrial fibrillation was higher (odds ratio, 5.89), the anterior mitral leaflet was thicker (odds ratio, 1.91), and the posterior mitral leaflet length was shorter (odds ratio, 1.58) in patients with aggravation of MR than in the remaining 113 patients. The mechanism of aggravated MR was poor coaptation associated with annular dilatation, thickened anterior mitral leaflet, and shortened posterior mitral leaflet.

CONCLUSIONS

A thickened anterior mitral leaflet and shortened posterior mitral leaflet, combined with mitral annular dilation associated with atrial fibrillation and restored left ventricular geometry, may aggravate MR after ASD closure. Careful follow-up is needed for patients with atrial fibrillation, a thickened anterior mitral leaflet, or a shortened posterior mitral leaflet.