Indexed on: 24 Sep '11Published on: 24 Sep '11Published in: The Annals of Thoracic Surgery
Although mild mitral regurgitation (MR) associated with atrial septal defect (ASD) is believed to improve by ASD closure alone, new-onset MR or aggravation of preexisting mild MR may also develop after ASD closure. We sought to determine the preoperative risk factors for the postoperative deterioration of mitral valve competence in adults with ASD.Retrospective review of 286 adults with ASD who had undergone surgical closure of ASD between January 2004 and December 2009 was performed. Patients with significant preoperative MR (≥III/IV) that necessitated mitral valve intervention were excluded. Preoperative MR grades were 0 in 204 patients, I in 67 patients, and II in 15 patients.After ASD repair, MR degree did not change or improved in most of the patients (204 of 286, 71%), whereas 82 patients (82 of 286, 29%) showed aggravated or new-onset MR, including 18 patients whose MR degree increased by grade 2 or more. Univariable analysis revealed older age, preoperative atrial fibrillation, large left atrial size, large indexed ASD size, high peak tricuspid regurgitation velocity, and associated tricuspid valve surgery or Maze procedure as risk factors for new-onset or aggravated MR, but only older age (odds ratio, 1.058; 95% confidence interval, 1.025 to 1.092; p = 0.0005) and indexed ASD size (odds ratio, 1.120; 95% confidence interval, 1.042 to 1.205; p = 0.0022) remained significant on multivariable analysis. The ratio of postoperative left ventricular end-diastolic volume to preoperative left ventricular end-diastolic volume was greater in patients with new-onset or aggravated MR (p = 0.016).Mitral valve competence may deteriorate after ASD closure in older patients with large ASD.