Usefulness of heart rate turbulence for predicting cardiac events in patients with nonischemic dilated cardiomyopathy

作者：Ikeda Takanori^*; Miwa Yosuke; Abe Atsuko; Nakazawa Kazuo

来源：Journal of Electrocardiology, 2011, 44(6): 669-672.

DOI：10.1016/j.jelectrocard.2011.08.003

• Heart rate turbulence
• Risk stratification
• Holter monitoring
• Nonischemic dilated cardiomyopathy

Background: Few studies have described the clinical value of heart rate turbulence (HRT), an autonomic risk stratification index, in stratifying patients with nonischemic dilated cardiomyopathy (NIDCM). We prospectively assessed the utility of HRT for cardiac events in patients with NIDCM.
Methods: We enrolled 134 consecutive patients with NIDCM. Heart rate turbulence was automatically measured using an algorithm based on 24-hour Holter electrocardiograms. In addition to HRT, other risk indices such as a reduced left ventricular ejection fraction of 30% or less, the presence of nonsustained ventricular tachycardia (VT), the use of medical treatment, and so on were assessed as well. The primary end point was defined as cardiac mortality and sustained VTs.
Results: Of the patients enrolled, 106 (79%) were used for HRT assessment. Heart rate turbulence was determined as positive in 26 patients (25%) and negative in 80 patients (75%). During a follow-up of 445 +/- 216 days, 23 patients (23%) reached the primary end point. Among indices, documented presence of nonsustained VT and an HRT-positive outcome had significant values with the primary end point (P=.02 and P=.0001, respectively). On multivariate analysis, an HRT-positive outcome was the most significant predictor, with a hazard ratio of 4.5 (95% confidence interval, 2.0-10.4; P=.0004).
Conclusions: Heart rate turbulence is a powerful risk stratification index for cardiac events defined as cardiac mortality and sustained VTs in patients with NIDCM.

• 出版日期2011-12