Mid-Term Follow-Up of Asymptomatic Coronary Arteriovenous Fistulas in Children

Background : Recently, improvements in echocardiography techniques have increased the diagnosis of small asymptomatic coronary arteriovenous fistula (CAVF). However, the natural history and incidence of spontaneous closure are unknown. Methods : We retrospectively analyzed all patients aged under 18 years with CAVF diagnosed via transthoracic two-dimensional doppler echocardiography between 2009 and 2019. Results : In total, 65 (34 boys) children were diagnosed with CAVF and were enrolled in the analysis. The median age at diagnosis was 4 (0 ‒ 86) months, and the mean follow-up period was 42 (0 ‒ 215) months. Spontaneous closure of CAVF was observed in 31 (48 ％ ) children. There was no significant difference in terms of closure rate according to gender. Meanwhile, the left and right coronary arteries remarkably differed in terms of CAVF patency according to origin ( p ＜ 0.05). Moreover, there was a significant difference between the pulmonary artery and the ventricle in terms of CAVF patency according to drainage ( p ＜ 0.05). One patient underwent coil embolization at the age of 1 year and 4 months. However, no other intervention was required. None of the patients had ischemia or heart failure during the clinical course. Conclusion : Approximately 48 ％ of patients experienced spontaneous closure of CAVF. The closure rate was higher than that previously reported, and it differed based on origin and opening of the fistula. Hence, assess-ment of the origin and opening of the fistula may be useful during follow-up.