[Clinical characteristics of spontaneous closure of congenital ventricular septal defect in children].

Objective

To investigate the occurrence of spontaneous closure in children with congenital ventricular septal defect (VSD), and to analyze the clinical and echocardiographic characteristics of different defect types.

Methods

In this retrospective cohort study, clinical data, including sex, age at initial diagnosis, physical examination findings, initial echocardiographic parameters, and follow-up outcomes of 1 483 children under 1 year old diagnosed with VSD by echocardiography at the Women and Children's Hospital Affiliated to Qingdao University from January 1, 2013 to August 31, 2025 were collected. The Turnbull nonparametric maximum likelihood method was used to estimate the cumulative probabilities of spontaneous closure at 1, 3, and 5 years after diagnosis. According to whether spontaneous closure occurred, patients were divided into spontaneous closure and non-closure groups. The baseline data of the two groups were compared. In the spontaneous closure group, patients were further classified into perimembranous, muscular, and subpulmonary groups according to anatomical location. The age at spontaneous closure and echocardiographic parameters were compared among the three groups. Intergroup comparisons were performed using Mann-Whitney U test, Kruskal-Wallis H test, χ² test, or Fisher's exact test.

Results

Among 1 483 VSD patients, there were 702 males (47.3%) and 781 females (52.7%). The age at initial diagnosis was 3.3 (1.5, 10.2) months, and the diameter of VSD (DVSD) was 4.4 (3.0, 6.0) mm. During the observation period, spontaneous closure was confirmed by echocardiography in 184 patients (12.4%). The highest observed proportion of spontaneous closure was found in patients with muscular type (19.4%, 34/175), followed by perimembranous type (12.3%, 147/1 195) and subpulmonary type (2.8%, 3/106). Turnbull analysis showed that the cumulative probabilities of spontaneous closure at 1, 3, and 5 years after diagnosis were 6.8% (95%CI 5.4%-8.9%), 18.4% (95%CI 15.4%-21.9%), and 27.2% (95%CI 21.6%-33.6%), respectively. Muscular type showed a relatively higher early cumulative probability of spontaneous closure, with 1 and 3-year estimates of 13.3% and 28.8%, respectively. The spontaneous closure group had significantly smaller DVSD and higher proportion of muscular type than the non-closure group (both P<0.05). The age at first echocardiographic confirmation of spontaneous closure in the overall spontaneous closure group was 24.5 (12.6, 43.1) months old. The age at spontaneous closure in muscular type was significantly younger than that in perimembranous type (P<0.05). The muscular type showed significantly smaller DVSD, DVSD/aortic diameter, maximal regurgitation pressure gradient, left ventricular end-diastolic volume/aortic diameter, and stroke volume/aortic diameter than the perimembranous type (all P<0.05), and was predominantly composed of small defects, significantly higher than perimembranous (P<0.05).

Conclusions

VSD has a considerable potential for spontaneous closure, which is closely related to defect type and size. Muscular VSD showed a relatively higher early cumulative probability of spontaneous closure and an earlier age at first confirmation of closure. Children with spontaneous closure tended to have smaller DVSD.