Casolo G C, Stroder P, Signorini C, Calzolari F, Zucchini M, Balli E, Sulla A, Lazzerini S
Clinica Medica I, University of Florence, Italy.
Circulation. 1992 Jun;85(6):2073-9. doi: 10.1161/01.cir.85.6.2073.
After acute myocardial infarction (AMI), several abnormalities of the autonomic control to the heart have been described. Heart rate (HR) variability has been used to explore the neural control to the heart. A low HR variability count measured 7-13 days after AMI is significantly related to a poor outcome. Little information is available on HR variability early after AMI and its relation to clinical and hemodynamic data.
We studied 54 consecutive patients (42 men and 12 women; mean age, 60.4 +/- 11 years) with evidence of AMI by collecting the 24-hour HR SD from Holter tapes recorded on day 2 or 3. We also measured HR variability in 15 patients with unstable angina and in 35 age-matched normal subjects. HR variability was lower in AMI than in unstable angina patients (57.6 +/- 21.3 versus 92 +/- 19 msec; p less than 0.001) and controls (105 +/- 12 msec; p less than 0.001). Also, HR variability was greater in non-Q-wave than in Q-wave AMI (p less than 0.0001) and in recombinant tissue-type plasminogen activator-treated patients with respect to the rest of the group (p less than 0.02). No difference was found for infarct site. HR variability was significantly related to mean 24-hour HR, peak creatine kinase-MB, and left ventricular ejection fraction (all p less than 0.0001). Patients belonging to Killip class greater than I or who required the use of diuretics or digitalis had lower counts (p less than 0.004, p less than 0.001, and p less than 0.024, respectively). Six patients died within 20 days after admission to the hospital. In these patients, HR variability was lower than in survivors (31.2 +/- 12 versus 60.9 +/- 20 msec; p less than 0.001), and a value less than 50 msec was significantly associated with mortality (p less than 0.025).
HR variability during the early phase of AMI is decreased and is significantly related to clinical and hemodynamic indexes of severity. The causes for the observed changes in HR variability during AMI may be reduced vagal and/or increased sympathetic outflow to the heart. It is suggested that early measurements of HR variability during AMI may offer important clinical information and contribute to the early risk stratification of patients.
急性心肌梗死（AMI）后，已描述了心脏自主神经控制的几种异常情况。心率（HR）变异性已被用于探索心脏的神经控制。AMI后7 - 13天测得的低HR变异性计数与不良预后显著相关。关于AMI早期的HR变异性及其与临床和血流动力学数据的关系，现有信息较少。
我们连续研究了54例有AMI证据的患者（42例男性和12例女性；平均年龄60.4±11岁），通过收集第2天或第3天记录的动态心电图磁带中的24小时HR标准差。我们还测量了15例不稳定型心绞痛患者和35例年龄匹配的正常受试者的HR变异性。AMI患者的HR变异性低于不稳定型心绞痛患者（57.6±21.3对92±19毫秒；p<0.001）和对照组（105±12毫秒；p<0.001）。此外，非Q波AMI患者的HR变异性高于Q波AMI患者（p<0.0001），且重组组织型纤溶酶原激活剂治疗的患者相对于组内其他患者HR变异性更大（p<0.02）。梗死部位无差异。HR变异性与24小时平均HR、肌酸激酶-MB峰值和左心室射血分数显著相关（均p<0.0001）。属于Killip分级大于I级或需要使用利尿剂或洋地黄的患者计数较低（分别为p<0.004、p<0.001和p<0.024）。6例患者在入院后20天内死亡。在这些患者中，HR变异性低于幸存者（31.2±12对60.9±20毫秒；p<0.001），且值小于50毫秒与死亡率显著相关（p<0.025）。
AMI早期阶段的HR变异性降低，且与严重程度的临床和血流动力学指标显著相关。AMI期间观察到的HR变异性变化的原因可能是迷走神经减少和/或心脏交感神经输出增加。建议在AMI期间早期测量HR变异性可能提供重要的临床信息，并有助于对患者进行早期风险分层。
