Initial syncope associated with alternating attacks of supraventricular tachycardia and atrioventricular block long after surgical correction of tricuspid atresia.

The Fontan procedure has become a generic term to define a surgical procedure that orients the systemic venous return directly to the pulmonary arteries, and has been used as a palliative operation for pulmonary atresia, tricuspid atresia, double inlet ventricle and complex single ventricle. The earliest type of Fontan procedure was a simple atriopulmonary anastomosis between the right atrium and the pulmonary artery. Atrial arrhythmias, particularly atrial flutter and sinus node dysfunction may occur in the early and late postoperative period after simple atriopulmonary anastomosis. The case presented here represents a much delayed occurrence of an initial syncope due to alternating attacks of SVT (supraventricular tachycardia) and second degree heart block on admission 21 years after simple atriopulmonary anastomosis performed for the correction of tricuspid atresia.