Analysis of the effects of the Blalock-Taussig shunt on ventricular function and the prognosis in patients with single ventricle.

Twenty-four patients with single ventricle, six with single left (SLV) and 18 with single right (SRV) ventricle, who received a Blalock-Taussig (BT) shunt at an average age of 3.2 years were studied. Ventricular function was assessed angiographically by end-diastolic volume index (EDVI) and ejection fraction (EF), and attempts were made to measure ventricular mass index (VMI) and VM/EDV. In 14 patients, the preoperative and postoperative results (average 2.4 years after placement of BT shunt) were compared in SLV (n = 5) and SRV (n = 9) groups. The SLV group showed significant increases in EDVI, VMI, and VM/EDV without a significant change in EF. The SRV group showed significant increases in EDVI and VMI, while EF decreased and VM/EDV was unchanged. Late death from congestive heart failure occurred in five patients with SRV. Three patients with atrioventricular valve regurgitation suffered late death. Among the patients with SRV, the late death group had significantly lower preoperative EF and VM/EDV compared with the survivors (n = 13). All of those with a preoperative EF of less than 0.50 and a VM/EDV of less than 0.35 g/ml suffered late death. In summary, patients with SRV appear to fail to develop adaptational hypertrophy to volume loading after the BT shunt procedure, with concomitant depression in ventricular pump function. Also, late cardiac failure seems likely to develop when low EF and VM/EDV are present preoperatively.