Department of Electrical Engineering, National Tsing Hua University, Hsinchu, Taiwan, ROC.
Ann Biomed Eng. 2011 Feb;39(2):835-49. doi: 10.1007/s10439-010-0180-6. Epub 2010 Oct 16.
Congestive heart failure (CHF) is a major medical challenge in developed countries. In order to screen patients with CHF and healthy subjects during circadian observation, accurate judgment and fast response are imperative. In this study, optimal timing during circadian observation via the heart rate variability (HRV) was sought. We tested 29 CHF patients and 54 healthy subjects in the control group from the interbeat interval databases of PhysioBank. By invoking the α1 parameter in detrended fluctuation analysis of HRV, we found that it could be used as an indicator to screen the patients with CHF and subjects in normal sinus rhythm (NSR) under Kruskal-Wallis test. By invoking Fano factor, the optimal timing to screen CHF patients and healthy subjects was found to be from 7 PM to 9 PM during the circadian observation. In addition, this result is robust in a sense that the same result can be achieved by using different ECG recording lengths of 2, 5, 10, … , and 120 min, respectively. Furthermore, a support vector machine was employed to classify CHF and NSR with α1 parameter of a moving half-hour ECG recordings via leave-one-out cross validation. The results showed that the superlative screening performance was obtained in the 7 pm-9 pm period during circadian observation. It is believed that this result of optimal timing will be helpful in the non-invasive monitoring and screening of CHF patients and healthy subjects in the clinical practice.
充血性心力衰竭（CHF）是发达国家面临的主要医学挑战。为了在昼夜节律观察期间筛选 CHF 患者和健康受试者，准确的判断和快速的反应至关重要。在这项研究中，我们通过心率变异性（HRV）寻求了昼夜节律观察的最佳时间。我们从 PhysioBank 的 Interbeat 间隔数据库中测试了 29 名 CHF 患者和 54 名健康对照组受试者。通过调用 HRV 去趋势波动分析中的α1 参数，我们发现它可以用作筛选窦性心律（NSR）的 CHF 患者和受试者的指标，通过 Kruskal-Wallis 检验。通过调用 Fano 因子，发现筛选 CHF 患者和健康受试者的最佳时间是在昼夜观察期间从下午 7 点到晚上 9 点。此外，该结果具有稳健性，因为通过分别使用不同的 ECG 记录长度 2、5、10、…和 120 分钟，都可以获得相同的结果。此外，通过使用带有移动半小时 ECG 记录的α1 参数的支持向量机通过留一法交叉验证对 CHF 和 NSR 进行分类。结果表明，在昼夜观察期间的晚上 7 点至晚上 9 点获得了最佳的筛选性能。据信，这一最佳时间的结果将有助于临床实践中对 CHF 患者和健康受试者的非侵入性监测和筛选。
