Clinical and hemodynamic results of the Fontan operation for tricuspid atresia

Abstract

Thirty patients aged 3 months to 26 years (median 9 years) with tricuspid atresia or severe tricuspid stenosis underwent a modified Fontan operation at Children's Hospital, Boston, between 1973 and 1980. Thirty-six palliative operations had been performed previously in 20 patients. Preoperative hemodynamic measurements included: mean pulmonary arterial pressure 6 to 18 mm Hg (median 9); pulmonary vascular resistance 0.3 to 2.2 Woods units/m 2 (median 1.5) and left ventricular end-diastolic pressure 3 to 14 mm Hg (median 7). There were five hospital deaths (17 percent), including two in the last 24 operations. The 25 survivors have been followed up for 4 to 85 months (median 23) with no late deaths. Twenty patients are in New York Heart Association class I and four in class II; one infant was not classified. Two patients have required reoperation, at, respectively, 71 and 26 months postoperatively; the former for late-developing conduit obstruction and residual bidirectional shunting; and the latter for a residual right to left shunt at atrial level. Early postoperative monitoring of hemodynamics in the intensive care unit revealed that a mean right atrial pressure of 17 mm Hg or greater, without obstruction of the anastomosis, was invariably associated with serious morbidity or mortality. Fifteen patients underwent elective cardiac catheterization 9 to 21 months (median 13) postoperatively. The mean right atrial pressure ranged between 5 and 12 mm Hg (median 8) and mean pulmonary arterial pressure between 4 and 11 mm Hg (median 7). The cardiac index (measured in 12 patients) was 1.9 to 4.0 liters/min per m 2 (median 3.2). The left ventricular ejection fraction measured in 11 patients did not change significantly postoperatively, remaining normal in 10. Three patients had a residual right to left shunt at atrial level while the arterial oxygen saturation in the remaining 12 patients was 93 to 97 percent. Thus the modified Fontan operation can be performed with excellent clinical and hemodynamic results in selected patients with tricuspid atresia.