Second Department of Internal Medicine, Kyorin University School of Medicine, Tokyo.
J Cardiovasc Electrophysiol. 2011 Oct;22(10):1135-40. doi: 10.1111/j.1540-8167.2011.02082.x. Epub 2011 May 3.
Previous studies have described the clinical utility of heart rate turbulence (HRT) as an autonomic predictor in risk-stratifying patients after myocardial infarction (MI). Some reports showed that diabetes mellitus (DM) affects the prognostic value of autonomic markers. We assessed the utility of HRT as a risk marker in post-MI patients with DM and without DM.
We prospectively enrolled 231 consecutive DM patients and 300 non-DM patients after acute MI. HRT was measured using an algorithm based on 24-hour Holter electrocardiograms (ECGs), assessing 2 parameters: turbulence onset (TO) and turbulence slope (TS). HRT was considered positive when both TO ≥0% and TS ≤2.5 ms/R-R interval were met. The endpoint was defined as cardiac mortality.
Of patients with DM, 9 patients (4%) were not utilized for HRT assessment because of frequent ventricular contractions or presence of atrial fibrillation. Forty-two of 222 patients (19%) were HRT positive. During follow-up of 876 ± 424 days, 26 patients (22%) reached the endpoint. Several factors including left ventricular ejection fraction (LVEF), renal dysfunction, documentation of nonsustained ventricular tachycardia (VT), and a HRT-positive outcome had significant association with the endpoint. Multivariate analysis determined that renal dysfunction and a positive HRT outcome had significant value with a hazard ratio (HR) of 4.7 (95%CI, 1.9-11.5; P = 0.0008) and 3.5 (95%CI, 1.4-8.8; P = 0.007), respectively. In non-DM patients, only a positive HRT outcome had significant value.
This study reveals that HRT detected by 24-hour Holter ECG can predict cardiac mortality in post-MI patients whether DM is present or not.
先前的研究已经描述了心率震荡（HRT）作为心肌梗死后（MI）患者自主神经预测指标的临床应用。一些报告显示，糖尿病（DM）会影响自主标志物的预后价值。我们评估了 HRT 在伴有或不伴有 DM 的 MI 后患者作为风险标志物的效用。
我们前瞻性纳入 231 例连续的 DM 患者和 300 例非 DM 患者。使用基于 24 小时动态心电图（ECG）的算法测量 HRT，评估 2 个参数：震荡起始（TO）和震荡斜率（TS）。当满足 TO≥0%和 TS≤2.5 ms/R-R 间期时，HRT 被认为是阳性。终点定义为心脏死亡率。
在 DM 患者中，由于频发室性收缩或存在心房颤动，有 9 例（4%）患者无法进行 HRT 评估。在 222 例患者中，有 42 例（19%）HRT 阳性。在 876±424 天的随访期间，26 例患者（22%）达到终点。包括左心室射血分数（LVEF）、肾功能不全、记录非持续性室性心动过速（VT）和 HRT 阳性结果在内的多个因素与终点显著相关。多变量分析确定肾功能不全和 HRT 阳性结果具有显著价值，风险比（HR）分别为 4.7（95%CI，1.9-11.5；P=0.0008）和 3.5（95%CI，1.4-8.8；P=0.007）。在非 DM 患者中，只有 HRT 阳性结果具有显著价值。
这项研究表明，通过 24 小时动态心电图检测的 HRT 可以预测 MI 后患者的心脏死亡率，无论是否存在 DM。
