B-type natriuretic peptide in heart transplantation: an important marker of allograft performance.

The successful management of a cardiac allograft recipient centers around detection of allograft dysfunction early and preferably in a noninvasive manner. Up to this point, echocardiography or right heart catherization with endomyocardial biopsy are the only definitive methods available to diagnose allograft dysfunction. However, these methods do not reflect early structural changes and neurohormonal aberrations involved in allograft dysfunction. B-type natriuretic peptide (BNP) reflects ventricular wall stress and pressure and early studies have intimated potential usefulness of this marker in heart transplantation. Recent studies utilizing point-of-care BNP assay in heart transplant recipients have demonstrated elevated BNP levels at baseline compared with controls. Furthermore, the two most significant correlates of BNP levels are central hemodynamic perturbations despite preserved systolic function and presence of right sided cardiac dysfunction. Initial investigations have demonstrated BNP levels to serve as prognostic marker for cardiac related events and to track responses to therapeutic interventions. Further studies are needed to further assess the utility of BNP as surrogate marker for cardiac function and adaptation.