Remodelling after surgical repair of atrial septal defects within the oval fossa

Abstract

In a retrospective study, we analysed the data from 101 adults with echocardiographic follow-up after surgical repair of defects within the oval fossa at a mean age of 35 +/- 17 years; 56% of the cohort being above the age of 30 years. Mean age at follow-up was 44 +/- 18 years, and length of follow-up was up to 40 years (11 +/- 12 years). At follow-up, atrial fibrillation or flutter was present in one quarter. Dilation of the right atrium, found in 64%, of the left atrium, found in 44%, and of the right ventricle, found in 29%, were also frequent, as well as pulmonary arterial hypertension, which was found in 30%. Diminished right ventricular ejection fraction, in contrast, was very rare, found only in 1%, and abnormal left ventricular ejection fraction was not encountered. By multivariate analysis, predictors for right or left atrial, or right ventricular, dilation were age at follow-up, degree of tricuspid regurgitation, pulmonary hypertension, and/or atrial fibrillation. In a subset of 21 patients in sinus rhythm, we correlated prospectively the diastolic and systolic function of both ventricles with levels of brain natriuretic peptide, comparing values to those of 20 age-matched controls with a mean age of 46 +/- 14 years. Levels of brain natriuretic peptide were significantly higher in patients than in controls (p = 0.006), and correlated significantly with diastolic dysfunction (p = 0.007) and left atrial size (p < 0.0001). In the long-term follow-up after surgical repair of defect within the oval fossa, therefore, complete normalization of heart size and function is rare. Despite preserved systolic function, persistent diastolic dysfunction is common and is associated with elevated levels of brain natriuretic peptide, which may explain the late occurrence of atrial arrhythmias.