The Blalock-Taussig shunt in infants: standard versus modified

In recent years, the modified Blalock-Taussig shunt--a polytetrafluoroethylene graft from the subclavian artery to the pulmonary artery--has been preferred over the standard shunt by some surgeons because (1) it requires less dissection and (2) length of native vessels is not critical. From January, 1979, to June, 1985, we operated on 51 infants less than 1 year of age, including 26 less than 1 week of age, to palliate severe complex cyanotic congenital cardiac malformations. Twenty-four modified Blalock-Taussig shunts and 29 standard Blalock-Taussig shunts were created. The groups were concurrent. We reviewed all available cineangiograms and measured branch pulmonary and subclavian arteries. Pulmonary artery index was not different preoperatively in patients given a modified versus a standard Blalock-Taussig shunt (144 +/- 118 and 118 +/- 59 mm2/m2, respectively), but it was greater postoperatively in patients with a modified shunt (431 +/- 188 and 189 +/- 106 mm2/m2) (p = 0.07). Distortion of the pulmonary artery occurred less often after a modified Blalock-Taussig shunt (4/11) than a standard Blalock-Taussig shunt (6/8) (p = 0.06), though none of the distortions was severe. Early and late shunt failure occurred less often with a modified shunt (5/24) than with a standard shunt (15/29) (p less than 0.05). The modified Blalock-Taussig shunt had advantages over the standard Blalock-Taussig shunt in our series: pulmonary artery growth was greater, distortion of pulmonary arteries was less commonly seen, and shunt failure occurred less often. Thus, in infants, we believe the modified Blalock-Taussig shunt should be considered a reasonable alternative to the standard Blalock-Taussig shunt.