Clinical significance of hyperbilirubinemia in patients with pulmonary hypertension undergoing heart-lung transplantation.

Hyperbilirubinemia is commonly observed in long-standing pulmonary hypertension and is thought to be the result of chronic right ventricular failure and subsequent liver congestion. To evaluate the clinical significance of preoperative hyperbilirubinemia, we reviewed the cases of 62 patients with pulmonary hypertension (31 primary and 31 Eisenmenger's syndrome) who underwent heart-lung transplantation between 1981 and 1990 at Stanford. Bilirubin levels higher than 1.0 mg/dl were noted in 58% of patients, and bilirubin levels higher than 2.0 mg/dl were noted in 23% of patients. Indirect hyperbilirubinemia accounted for 66% to 87% of the total bilirubin and tended to fluctuate with diuretic therapy. It was associated with polycythemia, reticulocytosis, and mild elevations of liver enzymes. Early postoperative mortality in patients with total bilirubin levels greater than 2.1 mg/dl, bilirubin levels greater than 1 mg/dl but less than 2.0 mg/dl, and levels less than 1 mg/dl was 58%, 27%, and 16%, respectively (p less than 0.05). In those with high bilirubin levels, four patients had severe hemorrhage as part of their terminal event. Cardiac cirrhosis was found at autopsy in 75% of the early deaths of patients with high bilirubin. We conclude that hyperbilirubinemia is a late manifestation of pulmonary hypertension. The mechanism of hyperbilirubinemia is probably the result of the combination of increased hemolysis and decreased uptake by the chronically congested liver. Patients with pulmonary hypertension and hyperbilirubinemia appear to be at greater surgical risk during heart-lung transplantation.