Intermediate to long-term outcome following congenital coronary artery fistulae closure with focus on thrombus formation

We sought to evaluate intermediate to long-term follow-up after coronary artery fistula (CAF) closure with emphasis on thrombotic complications. Transcatheter closure (TCC) or surgical closure (SC) is the current standard of treatment for significant CAF. Incidence and risk factors of coronary thrombosis after CAF closure have not been well described. Patients with CAF were identified from a departmental database and their medical records were retrospectively reviewed. CAFs were classified as proximal or distal based on origin and size as small, medium, or large. Of 16 patients, 12 underwent TCC and 4 SC. Median follow-up was 2.3 years (0.1 to 41.6). Myocardial infarction (MI) related to coronary thrombosis occurred in 3 patients; immediately, 0.9 year, and 42 years after closure. Ages at MI were 9.2, 57, and 49 years. All 3 had distal, large CAFs and underwent SC. Anticoagulation was used in 2 of 3 patients. In the remaining 13 patients, TCC was performed in 12 and SC in 1; mean age was 13.8 years (0.1 to 38.9). CAFs were proximal in 10 and distal in 3 and large in 10 and medium in 3. On follow-up, these patients were asymptomatic without MI. Anticoagulation was used in 9 of 13 after closure. In conclusion, patients with CAF are at risk for coronary artery thrombosis and MI after closure. Patients with distal type, large CAF, and older age at presentation may be at higher risk for coronary thrombosis. Close follow-up with anatomic and functional coronary evaluation is warranted in all patients after CAF closure.