The prognostic value of perfusion lung scintigraphy in patients who underwent single-lung transplantation for emphysema and pulmonary fibrosis.

UNLABELLED

The objective of this study was to evaluate the role of quantitative perfusion lung scintigraphy (QPLS) in predicting the development of chronic rejection in patients who underwent single-lung transplantation.

METHODS

Eighteen patients (15 men, 3 women; age range, 41-60 y; mean age, 54.6+/-6.0 y) who underwent single-lung transplantation for emphysema (n = 14) or pulmonary fibrosis (n = 4) were studied. Patients were evaluated using QPLS and pulmonary function tests before surgery and at 1-3 mo and 1-3 y after transplantation. Relative perfusion of the transplanted lung was calculated from standard perfusion lung scintigrams. Values for forced expiratory volume in the first second (FEV1) were obtained from lung function tests at the same time points. The maximal and minimal relative perfusion and FEV1 values in the early (1-3 mo) and late (1-3 y) follow-up periods were identified for each patient. Receiver operating curve (ROC) analysis was performed on all parameters.

RESULTS

In total, 82 lung scans were performed (mean, 4.8+/-1.55 per patient) and 484 FEV1 test determinations were obtained (mean, 30.0+/-15.6 per patient) during a follow-up period ranging from 8 to 84 mo (mean, 39.6+/-19.3 mo). In 7 of the 18 patients, chronic rejection developed, whereas 11 patients had a favorable outcome. No significant difference was found in the number of complications (acute rejection and infection episodes) between patients with a favorable outcome and patients with chronic rejection, up to 1 y after transplantation. At 1-3 mo, minimal relative perfusion values were 67.1%+/-12.2% in the favorable outcome group and 50.8%+/-9.6% in the chronic rejection group (P = 0.02). Before surgery and at 1-3 y, minimal relative perfusion was not significantly different between the 2 groups. The difference in maximal relative perfusion at 1-3 y was marginally significant, with 76.5%+/-8.9% in the favorable group and 64.3%+/-15.0% in the chronic rejection group (P = 0.051). FEV1 values were not significantly different preoperatively and 1-3 mo after surgery between the chronic rejection and the favorable outcome groups. Late in the follow-up period (1-3 y), FEV1 values in the chronic rejection and favorable outcome groups were 35.6%+/-7.9% and 56.9%+/-13.6%, respectively (P = 0.002). ROC analysis of minimal relative perfusion at 1-3 mo identified a threshold of 57% under which the sensitivity and specificity for chronic rejection were 83% and 88%, respectively. Minimal FEV1 for the same period identified a threshold of 48% under which the sensitivity and the specificity were 80% and 67%, respectively.

CONCLUSION

QPLS early after transplantation in our patients predicted the development of chronic rejection in patients with single-lung transplantation for emphysema and pulmonary fibrosis, whereas surgical complications, acute rejection, infection episodes, and lung function tests did not predict the outcome. This early prediction could not be obtained from lung function tests performed at the same time.