Should Early Acceleration of Heart Rate During Exercise Be Used to Risk Stratify Patients With Suspected or Established Coronary Artery Disease?

xercise is one of the most common noninvasive stressors used to risk stratify patients with suspected or established coronary disease. Functional capacity, time to onset of demand-induced ischemic ST-segment shifts or angina, complex ventricular arrhythmias, a progressive fall in systolic blood pressure during exercise, and abnormal heart rate (HR) responses either during or after exercise are all well-established independent predictors of long-term outcome and, when used in combination, have the potential to identify prognostic high-risk patients who may be candidates for coronary angiography and coronary revascularization. 1 Among HR variables tested that are predictive of mortality, the most common include the ability to augment HR to age-predicted maximum (chronotropic response), the HR recovery response in the immediate postexercise phase, and the ST-segment response corrected for HR. 2,