Multimarker approach to evaluation of cardiac toxicity during preparative regimen and hematopoietic cell transplantation

Cardiac toxicity of preparative regimen (PR) containing high-dose Cyclophosphamide (120 mg/kg) followed by hematopoietic cell transplantation (HCT) was evaluated with 6 biomarkers of cardiac injury: N-terminal pro brain natriuretic peptide (NT-proBNP), creatine kinase MB (CK-MB mass), cardiac troponins (cTnT, cTnI), heart-type fatty acid binding protein (H-FABP), glycogen phosphorylase BB (GPBB). Twenty-three patients (mean age 44.5+/-10.6 years, 15 males) with acute leukemia were studied. All biomarkers were measured the day before PR, the day after PR, the day after HCT and 14 days after HCT. We found NT-proBNP elevations above 500 ng/L in 6 (26.1 %) patients after PR, in 9 (39.1 %) after HCT and in 7 (30.4 %) 14 days after HCT. GPBB became elevated (above 7.30 microg/L) in 5 (21.7 %) patients after PR, remained elevated in 5 (21.7 %) after HCT and in 2 (8.7 %) 14 days after HCT. A significant correlation between elevation in NT-proBNP and GPBB was found. Other markers remained within the reference range early after PR and HCT. Our findings show that administration of PR and HCT for acute leukemia is associated with acute neurohumoral activation of cardiac dysfunction (significant rise in NT-proBNP) and may lead to GPBB elevation. These changes could indicate acute cardiac toxicity due to treatment and require further follow-up. The predictive value for development of cardiomyopathy in the future is unclear. Further studies will be needed to define the potential role of new biomarkers in this context.