Balloon dilation for postoperative pulmonary stenosis following surgical creation of an intrapulmonary coronary arterial tunnel

Balloon dilation was performed in four patients with postoperative pulmonary stenosis who had undergone surgical creation of a coronary arterial tunnel in the pulmonary trunk. Two patients had complete transposition in whom the arterial switch operation had been performed using the modified Aubert method. The other two patients had anomalous origin of the left coronary artery from the pulmonary trunk treated with the Takeuchi procedure. Balloon dilation was performed at 11 locations. The pressure gradient decreased from 48 ± 22 to 24 ± 14mmHg (p<0.01), and the diameter of the narrowest segment increased from 5.3 ± 2.5 to 7.5 ± 2.8mm (p<0.01), respectively. Of the 11 procedures, 8 (73%) were judged successful with use of the criterion of success as a greater than 50% decrease in pressure gradient, and/or a greater than 50% increase in diameter. The inflated balloon must have compressed the coronary arterial tunnel in the pulmonary trunk, but there was no apparent myocardial damage in any patient, although transient and mild ST-T changes appeared on electrocardiographic monitoring during the procedure in 2 patients. Rupture of the wall of the pulmonary trunk occurred in two patients, one of whom required elective surgical intervention. These data suggest that balloon dilation should be performed with caution for management of postoperative pulmonary arterial stenosis in patients with a surgically created intrapulmonary coronary arterial tunnel, since tearing the wall of the pulmonary trunk may occur.