The analysis of the parameters of 24-hr ECG Holter monitoring in patients with blood neoplasms undergoing high-dose chemotherapy and stem cell transplantation.

Background: Hematopoietic stem cell transplantation (HSCT) is a widely used procedure in the treatment of malignant diseases, including blood neoplasms and has increased survival in hematological diseases. The aim of the study was to analyze parameters of 24-hr ECG monitoring in patients with selected blood neoplasms in whom the procedure of hematopoietic stem cell transplantation was performed.

Methods: The study group consisted of 64 adults diagnosed with hematologic cancer qualified for HSCT with the previous high dose chemotherapy (HDC). In all patients 24-hr Holter monitoring was carried out twice. First examination took place prior to the HSCT procedure, and the second after finishing the procedure of HSCT.

Results: The minimal and mean heart rate (HR min and HR max) from 24-hr ECG recording was statistically significantly higher after the transplantation in comparison with the first test. The number of premature ventricular complexes (PVCs) was higher in the test after HSCT. In the second examination there was significantly higher percentage of premature ventricular complexes, incidents of tachycardia, and Mobitz type 1 second degree atrioventricular block. In regression analysis, in a group of patients with blood neoplasms after HSCT and HDC, administration of cyclophosphamide, fludarabine and total body irradiation were independent risk factors for electrocardiographic abnormalities in 24-hr Holter monitoring, that is, the increase in HR min, HR mean and PVCs.

Conclusion: In patients with blood neoplasms undergoing HSCT more electrocardiographic abnormalities may be found after this procedure in comparison with the 24-hr Holter monitoring before transplantation.