PROGNOSIS OF PATIENTS WITH CYSTIC-FIBROSIS AWAITING HEART AND LUNG TRANSPLANTATION

Heart-lung transplantation is a successful treatment for patients with cystic fibrosis and chronic respiratory failure. Patients are assesse d for surgery when life expectancy is deemed short. This study assesse s the ability of measurements of pulmonary function, blood gas levels, and nutritional status to predict survival of patients awaiting heart -lung transplantation and to assess the effect of heart-lung transplan tation on survival. Sixty-seven patients with cystic fibrosis were acc epted for heart-lung transplantation from 1985 through 1990. Each pati ent underwent tests of pulmonary function, exercise tolerance, blood-g as levels, and nutritional status. Cox regression was used to analyze the prognostic value of these data. Of the 67 patients accepted for he art-lung transplantation, organs became available for 30; 24 patients died waiting, and 13 patients were on the list December 31, 1990. Eigh t patients died after transplantation. Patients with above-average for ced expiratory volume in 1 second (FEV1) (median, 17% predicted) at as sessment were half as likely to die waiting (relative risk, 0.47; 95% confidence interval, 0.23 to 0.97) as patients with below-average FEV1 . The relative risk of death for patients on the waiting list was 1.44 (95% confidence interval, 1.17 to 1.77) for each increment in PCO2 of 1 kPa. No effect of nutritional status on waiting list death was foun d, but seven of eight patients who died after heart-lung transplantati on were below 80% predicted weight for height. Using a time-dependent analysis, heart-lung transplantation almost halved the risk of death ( relative risk, 0.57; 95% confidence interval, 0.22 to 1.48). Postopera tive actuarial survival was 79% (95% confidence interval, 63% to 95%). The measurements of FEV1 and arterial PCO2 were the most reliable pro gnostic indicators. Referral of patients with cystic fibrosis is sugge sted before the FEV1 falls below 20% predicted and while arterial PCO2 remains normal.