Pulmonary function after successful heart transplantation; One year follow-up

Congestive heart failure (CHF) has been associated with the development of restrictive ventilatory abnormalities and decreased pulmonary diffusing capacity. Whether these physiologic changes reflect permanent alterations of lung anatomy or result solely from potentially reversible alterations of lung water is not known. To examine this issue, we reviewed the pulmonary function tests (PFTs) and cardiac catheterization data from recipients of successful heart transplants prior to and 1 year after transplantation. Thirty-eight patients met the inclusion criteria (median age, 52 years). The median duration of symptomatic CHF prior to transplantation was 22 months (range, 3 to 72 months). After transplantation, spirometry revealed an improvement in FEV₁ from 75.8±3.5 to 99.1±2.8 percent of predicted and FVC from 81.3±3.7 to 101.6±3.0 percent of predicted (p<0.001). The FEV₁/FVC ratio remained unchanged at 80 percent. Nonsmokers and former smokers had similar improvements in spirometry after transplantation. The TLC improved from 91.1±3.3 to 105.5±2.9 percent of predicted (p<0.001); this improvement was due to an increase in inspiratory capacity. Diffusing capacity for carbon monoxide was decreased before transplantation and showed a small decline after transplantation from 82.3±3.2 to 76.8±2.6 percent of predicted (p<0.05). After correction of severe CHF by cardiac transplantation, normalization of FEV₁, FVC, and TLC can be anticipated. Diffusing capacity, however, may actually decline after transplantation.