The modified Blalock-Taussig shunt: analysis of adequacy and duration of palliation.

The modified Blalock-Taussig shunt provides excellent palliation for patients with cyanotic heart disease and may be the optimal shunt for infants less than 3 months old. The duration of palliation with flow limited by a fixed conduit between the subclavian and pulmonary artery is unknown. Between October 1980 and June 1985 forty-nine patients received 55 shunts. Age at operation was 1 day to 15 years (median 2 weeks), with 29 patients less than 3 months old. Weights were 1.7 to 53 kg, with 31 patients less than 5 kg. There were two early (4%) and four late (9%) deaths, none shunt related. The 43 late survivors were followed from 2 to 60 months (mean 27 +/- 16). Late study in 32 patients revealed a mean PO2 of 52 +/- 2 mm Hg. No patient had pulmonary arterial distortion or hypertension. In 10 patients inadequate shunt function was noted from 12 to 34 months after operation (mean 28 +/- 10). There were no sudden failures and all shunts remained patent. Univariate analysis revealed that age less than 3 months (p = .0154) and weight less than 3.6 kg (p = .0110) were risk factors predictive of earlier shunt failure. The mean satisfactory shunt survival time for these two groups was 38 +/- 3.6 and 35 +/- 3.7 months, respectively. The presence of pulmonary atresia (p = .1175) and the specific diagnostic group (p = .7620) were not of themselves risk factors.(ABSTRACT TRUNCATED AT 250 WORDS)