Spontaneous closure of muscular ventricular septal defects

Introduction/Objective. Ventricular septal defect (VSD) is the most frequently diagnosed congenital heart anomaly. The prognosis is usually good as it has spontaneous closure evolution, especially small muscular VSDs. The aim of this study was to determine the natural history of isolated muscular VSDs including the frequency of spontaneous closure in relation to location in the muscular septum and the age at the time of closure. Methods. The study included 96 children (52 girls and 44 boys) with isolated muscular VSD diagnosed during the first month of life. We analyzed the tendency of spontaneous closure of these defects for the duration of childhood during a follow-up period of 16 years. Two-dimensional color Doppler echocardiography was performed to detect muscular VSD as a primary cardiac lesion. There was significant prevalence of small apical versus trabecular defects and their outcomes were evaluated. Results. Our study evaluated 91 children, 49 (53.8%) girls and 42 (46.2%) boys who did not undergo surgery. Apically located VSD was diagnosed in 68 (74.7%), while trabecular defects were found in 23 (25.3%) children. Spontaneous closure occurred in 56 out of 91 cases (61.5%). The time of spontaneous closure was most commonly recorded during the first six months after birth (46.4%). The overall rate of spontaneous closure was 81.3% by the end of the first year. Apically located ventricular defects underwent spontaneous closure in the majority of patients, in comparison to trabecular ventricular defects (χ2 = 12.581; p < 0.001). Kaplan–Meier analysis demonstrated a significant difference in the average time required for spontaneous closure between the analyzed patient groups (log-rank = 9.64, p = 0.002). Conclusion. The frequency of spontaneous closure of muscular VSDs, especially apically located, is very high in the first six months, especially within the first year of life. It is advisable to detect them early on using color flow imaging and to follow up patients up to spontaneous closure