Absolute Indications
- Suspicion of a myocardial infarction or acute myocardial infarction (heart attack)
- Onset of moderate-to-severe angina (chest pain)
- Drop in systolic blood pressure (SBP) below standing resting pressure or drop in SBP with increasing workload accompanied by signs or symptoms
- Signs of poor perfusion (circulation or blood flow), including pallor (pale appearance to the skin), cyanosis (bluish discoloration), or cold and clammy skin
- Severe or unusual shortness of breath
- CNS (central nervous system) symptoms
- e.g., ataxia (failure of muscular coordination), vertigo (An illusion of dizzying movement), visual or gait (pattern of walking or running) problems, confusion
- Serious arrhythmias (abnormal heart rhythms)
- e.g.: second / third degree AV block, atrial fibrillation with fast ventricular response, increasing premature ventricular contractions or sustained ventricular tachycardia)
- Technical inability to monitor the ECG
- Patient's request (to stop)
Relative Indications
- Any chest pain that is increasing
- Physical or verbal manifestations of shortness of breath or severe fatigue
- Wheezing
- Leg cramps or intermittent claudication (grade 3 on a 4-point scale)
- Hypertensive response (SBP >260 mm Hg; DBP>115 mm Hg)
- Pronounced ECG changes from baseline
- >2 mm of horizontal or down sloping ST- segment depression, or >2 mm of ST-segment elevation (except in aVR)
- Exercise-induced bundle branch block that cannot be distinguished from ventricular tachycardia
- Less serious arrhythmias (abnormal heart rhythms) such as supraventricular tachycardia