Significant and Morbid Changes in Heart Rate Variability Precedes and Complicates Symptomatic Hypotension in Peripheral Blood Stem Cell Apheresis.

Peripheral blood stem cell harvest (PBSCH) has been widely performed for rescue following high-dose chemotherapy or as an alternative to BMT for allogeneic stem cell transplantation. However, severe complications, which caused sudden death, were reported in PBSCH from healthy donors. Recent cumulative evidence shows that decrease in cardiovascular signal variability of the R-R period (heart rate variability, HRV) is strongly associated with sudden death and/or cardiac event after a myocardial infarction. Furthermore, usefulness of HRV as a clinical tool has been explored in numerous conditions such as hypertrophic cardiomyopathy, obstructive sleep apnea, diabetic neuropathy, and various neurological alterations. Two types, time domain and frequency domain, are included in HRV analysis. In this study, we investigated HRV during and after apheresis for PBSCH in 23 cases [8 autologous transplant patients, 15 allogeneic transplant donors; 8 men, 15 women; median age 47 years (27–55)]. Date from 24-hour ambulatory ECG recordings were analyzed with R-R data analysis software (MemCalc/CHIRAM version 1, Suwatrust, Tokyo, Japan). Acknowledged simple markers in time domain analysis are the standard deviation of all normal beats (SDNN) and the square root of the mean of the sum of squared differences between adjacent normal-to-normal intervals (r-MSSD). On the other hand, markers in frequency domain analysis include LH, low frequency power (0.04–0.15Hz); HF, high frequency power (0.15–0.4 Hz); LH/HF ratio; VLF, very low frequency power (0.003–0.04 Hz); and ULF, ultra low frequency power (