Chin C F, Messenger J C, Greenberg P S, Ellestad M H
Clin Cardiol. 1979 Feb;2(1):12-8. doi: 10.1002/clc.4960020103.
Patients with chronotropic incompetence, defined as a failure of the heart rate response to exercise to rise to within two standard deviations of the expected increase with exercise, where studied and compared to patients with known coronary disease by angiogram with and without ST segment depression. 72% of the patients with chronotropic incompetence but without ST depression had significant coronary heart disease. The demonstration of chronotropic incompetence in exercise testing has important predictive implications and should be looked upon as carefully as ST segment changes. There was no evidence of SA node ischemia in these patients. Intrinsic heart rate measurements done in this study suggest autonomic dysfunction as a possible pathophysiologic mechanism for chronotropic incompetence. The heart rate response to exercise may be a useful predictor of the presence and severity of coronary disease. Therefore, a predicted heart rate response with standard deviation for age and sex should be included as part of the stress test protocol.
变时性功能不全的患者被定义为运动时心率反应未能上升至预期运动增加量的两个标准差范围内，对这些患者进行了研究，并与通过血管造影术诊断为患有或未患有ST段压低的已知冠心病患者进行了比较。72% 变时性功能不全但无ST段压低的患者患有严重冠心病。运动试验中变时性功能不全的表现具有重要的预测意义，应与ST段改变一样仔细看待。这些患者没有窦房结缺血的证据。本研究中进行的固有心率测量表明自主神经功能障碍可能是变时性功能不全的病理生理机制。运动时的心率反应可能是冠心病存在和严重程度的有用预测指标。因此，应将根据年龄和性别计算的预测心率反应及标准差纳入应激试验方案。
