Prognostic value of brain natriuretic peptide in heart transplant patients.

BACKGROUND

Continuously elevated B-type natriuretic peptide B (BNP) levels are associated with adverse prognosis in heart failure, but this has been less well established in heart transplantation, where medium- to long-term studies are lacking. The purpose of this study was to determine whether BNP levels determined in the first year of transplant have prognostic implications for subsequent outcome.

METHODS

A retrospective case-control study was carried out in 71 heart transplant patients with a total of 488 biopsies and BNP determinations. Determinations that might raise BNP levels (rejection, high lung pressures, renal dysfunction, depressed ventricular function and graft vascular disease) and those obtained in the first 4 months were excluded. The final analysis included 56 patients with 155 BNP determinations spread over Months 5, 7, 9 and 12. Two groups were made according to the presence of major events after the first year (death, late rejection and ventricular dysfunction associated or not with graft vascular disease): group with events: 13 patients, 37 determinations; group without events: 43 patients, 118 determinations.

RESULTS

There were no differences in the clinical profile of the patients. Mean follow-up was 6 years. Mean BNP was higher in the events group for determinations at Month 5 [event: 140 (95), no events: 68 (68); p = 0.01], Month 7 [event: 174 (32), no event: 66 (65); p = 0.002], Month 9 [event: 143 (37), no event: 58 (54); p = 0.002] and Month 12 [event: 126 (55), no event: 48 (37); p = 0.001]. The receiver-operator characteristic (ROC) curve showed that a BNP value of 100 pg/ml classified patients with a sensitivity of 80% and a specificity of 75% (p = 0.0001).

CONCLUSIONS

BNP values determined in the first year of transplant might help to distinguish a sub-group of patients with a higher rate of significant complications in long-term follow-up.