Evaluation of heart rate variability in patients with coronary artery ectasia and coronary artery disease.

OBJECTIVE The present study compared heart rate variability (HRV) parameters in patients with coronary artery ectasia (CAE) and coronary artery disease (CAD). METHODS The study population consisted of 60 consecutive patients with CAE (14 women; mean age 51.63±7.44 years), 60 consecutive patients with CA (15 women; mean age 53.67±9.31 years), and 59 healthy individuals (13 women; mean age 52.85±8.19 years). Electrocardiograms, 24-hour Holter analyses, and routine biochemical tests were performed, and clinical characteristics were evaluated. Coronary angiography images were analyzed. Time-domain HRV parameters, including the standard deviation (SD) of normal-to-normal intervals (SDNN) and the root mean square of difference in successive normal-to-normal intervals (RMSSD) were evaluated, as were frequency-domain HRV parameters including low-frequency (LF), very low-frequency (VLF), high-frequency (HF), the proportion derived by dividing low- and high-frequency (LF/HF), and total power (TP). RESULTS SDNN was lower in both the CAE and CAD groups, compared to the healthy group (140.85±44.21, 96.51±31.28, and 181.05±48.67, respectively). A significant difference in RMSSD values among the groups was determined (p=0.004). Significantly decreased VLF and HF values were found in the CAE group, compared with the healthy group (VLF p<0.001; HF, p=0.007). TP, VLF, and HF values were significantly lower (p<0.001, p<0.001, and p<0.001, respectively), but LF and LF/HF values were significantly higher (p<0.001 for both) in the CAD group than in the healthy group. TP values were significantly higher (p<0.001), and LF and LF/HF values were lower in the CAE group, compared with the CAD group (p<0.001 for both). CONCLUSION A decrease in vagal modulation or an increase in sympathetic activity of cardiac function, assessed by HRV analysis, is worse in patients with CAD than in patients with CAE.