The Early “Unnatural” History Following Surgical Repair of Ventricular Septal Defects

INTRODUCTION: Surgical outcomes for simple ventricular septal defects (VSD) have been excellent in the past three decades. For this project, the timing of resolution of left-sided dilation and mitral regurgitation (MR) following VSD repair was assessed. METHODS: Echocardiographic data surrounding surgery of 42 consecutive children who underwent surgical patch repair of a VSD were reviewed. The echocardiograms were reviewed up to a mean of 12 months post-operatively (range 9 – 14 months). Quantitative data indexed to body surface area including left atrial (LA) volume, mitral valve annulus diameter, and left ventricular end-diastolic dimension (LVEDD) was analyzed. RESULTS: The majority of our pre-surgical cohort had only trace (44%) or no MR (31%), with a small proportion having mild (16%) or moderate MR (9%). No patients had moderate or greater MR following repair at follow-up. The median mitral valve annular Z-score was 1.8 (SD 1.6; range: −1.2 to 4.1) pre-operatively, improving to a 0.6 (range: −1.7 to 2.4; p < 0.001) at follow-up. LA dilation was present in 70% of patients, with a median LA volume Z-score of 1.1 (range: −2.6 to 15.5), decreasing to 13% median Z-score −1.2 (range: −3.5 to 2.9; p < 0.001) at follow-up. LV dilation was present in 81% of pre-operative patients with a median LVEDD Z-score of 3.0 (range: −2.0 to 7.9). There was significant improvement in qualitative assessment of LV enlargement (25%) with a median LVEDD Z-score of 0.5 (range: −2.1 to 2.9; p < 0.001) at follow-up. Discharge echocardiogram was performed at a mean of 5.7 days (range: 3 – 12 days) following surgery. CONCLUSIONS: Normalization of LA, mitral valve annulus, and LV size occurred within the first three months in the majority of patients, with significant changes occurring within the first post-operative week following surgical repair for VSD.