Biochemical Markers of Cardiotoxicity of High-Dose Chemotherapy and Autologous Hematopoietic Stem Cell Transplantation in Patients with Malignant Lymphoproliferative Disorders

Background. High-dose chemotherapy (HDCT) with autologous hematopoietic stem cells transplantation (auto-HSCT) is an effective therapeutic option for patients with Hodgkin’s lymphoma and aggressive non-Hodgkin’s lymphomas in those cases, when the standard chemotherapy combined with the radiation therapy proves to be ineffective. The HDCT and auto-HSCT are also basic treatment options for multiple myeloma. However, toxic effects of the transplantation, including cardiotoxicity, may significantly worsen the prognosis of patients who receive this treatment. Aim. To evaluate changes in biochemical markers of cardiotoxicity (troponin and N-terminal prohormone of brain natriuretic peptide (NT-proBNP)) in patients with malignant lymphomas (receiving HDCT and auto-HSCT). Materials & Methods. 157 patients were enrolled in the study. The sensitivity threshold of the troponin T test was 0.1 ng/mL and troponin I 0.001 ng/mL (highly sensitive troponin). Troponin T (conventional troponin) was measured in 56 patients, troponin I was assessed in 101 patients. Serum troponin levels were evaluated before the conditioning, on D0, D+7, and D+12. The level of NT-proBNP was assessed before the conditioning, on D0 and D+12. Results. Increased troponin T level was observed in 2 of 56 patients (3.6 %), increased troponin I level — in 27 of 101 patients (26.7 %) (p < 0.01). Troponin levels were within normal limits in all patients at admission. Troponin T levels increased only on D+7. Troponin I level increased in 4 patients (4 %) on D0, in 17 patients (16.8 %) on D+7 and in 11 patients (10.9 %) on D+12. The median concentration of troponin I was 0.215 ng/mL after HDCT completion, 0.74 ng/mL on D+7 and 0.21 ng/mL on D+12. No cases of myocardial infarction were observed. NT-proBNP levels in most patients were within normal limits at admission (median level 79.2 pg/mL). The situation changed significantly after conditioning: in most patients the level was almost twice as high as the upper normal limit (medial 240.6 pg/mL). Significant differences in levels of NT-proBNP (p < 0.05) were observed at comparison of data before conditioning and D0, and before conditioning and D+12. Conclusion. The data obtained confirm a significant impact of HDCT and auto-HSCT on the cardiovascular system of patients with malignant lymphomas. Further studies and observation of the patients are needed to clarify the prognostic significance of the findings related to cardiotoxicity (in particular, congestive heart failure).