Objective: Systemic-to-pulmonary collateral vessels can develop in patients with obstruction of the right ventricular outflow tract or the pulmonary artery. Occlusion of these vessels is necessary before surgical correction of the primary disease. We report the results of transcatheter coil embolization in the treatment of 56 patients.
Materials and methods: Seventy-four procedures were done in the perioperative period for treatment of 67 aortopulmonary collateral arteries, five modified Blalock-Taussig shunts, and two enlarged veins.
Results: In the "aortopulmonary collateral" group, occlusion was complete in 51 patients (76%), subtotal in seven (10%), partial in four (6%), and failed in five (8%). Inadvertent embolization to the aorta occurred in two procedures, but both coils were retrieved nonsurgically. During follow-up of 1-12 months (n = 32; mean, 6.3 months), the coils remained in position, without any migration. Follow-up angiograms in 14 embolized vessels showed no recanalization (mean, 5.3 months; range, 2-12 months). In the "shunt" group, occlusion was complete in four patients and failed in one. Distal embolization to the pulmonary artery occurred in one patient. This coil was retrieved during surgery. During follow-up of 3-6 months, coils remained in position in all patients. In one patient, a follow-up angiogram at 3 months showed no recanalization. In the "venous embolization" group, occlusion was complete in one patient. The coils were in position 5 months later. The procedure was unsuccessful in the other patient.
Conclusion: We conclude that transcatheter coil embolization is useful in the treatment of abnormal systemic-to-pulmonary vessels and shunts in patients with obstruction of the right ventricular outflow tract or the pulmonary artery. Homemade coils are safe and effective in obliterating antegrade flow.