Division of modified Blalock-Taussig shunt at correction avoids distortion of the pulmonary artery

Background. Modified Blalock-Taussig (BT) shunt causing pulmonary artery distortion has been reported. This distortion may get worse after a corrective operation if the BT shunt is ligated, rather than divided. In this study we examined whether division of modified BT shunt at the time of corrective operation would allow pulmonary artery growth and avoid further distortion. Methods. Fifteen patients who had modified BT shunts and subsequently had corrective operations performed by one surgeon between January 1980 to December 1990 were analyzed. The median time from the BT shunt to corrective operation was 46.3 months (range, 3 to 119 months). At the time of corrective procedure, the BT shunt was divided and metal clips were used to occlude and mark each end. At follow-up a chest roentgenogram was obtained and the distance between the two clips was measured. Results. In all 15 patients measured sequentially the distances between the two clips increased steadily. Conclusions. Division of BT shunt at the time of corrective procedure reduces pulmonary artery distortion.