Effect of Blalock Taussig shunt on clinical parameters, left ventricular function and pulmonary arteries.

Twenty children (mean age 3.25 years) with congenital cyanotic heart disease undergoing modified left Blalock-Taussig (BT) shunt were studied. The mean follow-up period was 9.5 months (range 6 months to 1 year). The shunt was performed for cyanotic spells in 15 (75%) and hypoplastic pulmonary arteries in 5 (25%) patients. There were no immediate or late complications. None had cyanotic spell after the shunt. The mean arterial oxygen saturation improved from 66.47 +/- 11.9 to 76.97 +/- 8.16% (p = 0.0003) and mean hematocrit decreased from 51.55 +/- 9.5 to 46.5 +/- 9.7 (p = 0.002) after the shunt. The left atrial systolic volume and left ventricular diastolic volume also increased significantly following the shunt (from 15.82 +/- 6.37 to 20.83 +/- 8.91 ml p = 0.006 and from 36.13 +/- 16.08 to 41.08 +/- 20.07 ml (p = 0.01) respectively. There was significant growth of main, right and left pulmonary arteries and pulmonary valve annulus after the procedure.