Contraindications and termination conditions




Stress cardiac imaging is not recommended for asymptomatic, low-risk patients as part of their routine care. Some estimates show that such screening accounts for 45% of cardiac stress imaging, and evidence does not show that this results in better outcomes for patients. Unless high-risk markers are present, such as diabetes in patients aged over 40, peripheral arterial disease; or a risk of coronary heart disease greater than 2 percent yearly, most health societies do not recommend the test as a routine procedure.

Absolute contraindications to cardiac stress test include:

  • Acute myocardial infarction within 48 hours
  • Unstable angina not yet stabilized with medical therapy
  • Uncontrolled cardiac arrhythmia, which may have significant hemodynamic responses (e.g. ventricular tachycardia)
  • Severe symptomatic aortic stenosis, aortic dissection, pulmonary embolism, and pericarditis
  • Multivessel coronary artery diseases that have a high risk of producing an acute myocardial infarction
  • Decompensated or inadequately controlled congestive heart failure
  • Uncontrolled hypertension (blood pressure>200/110mm Hg)
  • Severe pulmonary hypertension
  • Acute aortic dissection
  • Acutely ill for any reason

Indications for termination:

A cardiac stress test should be terminated before completion under the following circumstances:

Absolute indications for termination include:

  • Systolic blood pressure decreases by more than 10 mmHg with increase in work rate, or drops below baseline in the same position, with other evidence of ischemia.
  • Increase in nervous system symptoms: Dizziness, ataxia or near syncope
  • Moderate to severe anginal pain (above 3 on standard 4-point scale)
  • Signs of poor perfusion, e.g. cyanosis or pallor
  • Request of the test subject
  • Technical difficulties (e.g. difficulties in measuring blood pressure or EGC)
  • ST Segment elevation of more than 1 mm in aVR, V1 or non-Q wave leads
  • Sustained ventricular tachycardia

Relative indications for termination include:

  • Systolic blood pressure decreases by more than 10 mmHg with increase in work rate, or drops below baseline in the same position, without other evidence of ischemia.
  • ST or QRS segment changes, e.g. more than 2 mm horizontal or downsloping ST segment depression in non-Q wave leads, or marked axis shift
  • Arrhythmias other than sustained ventricular tachycardia e.g. Premature ventricular contractions, both multifocal or triplet; heart block; supraventricular tachycardia or bradyarrhythmias
  • Intraventricular conduction delay or bundle branch block or that cannot be distinguished from ventricular tachycardia
  • Increasing chest pain
  • Fatigue, shortness of breath, wheezing, claudication or leg cramps
  • Hypertensive response (systolic blood pressure > 250 mmHg or diastolic blood pressure > 115 mmHg)

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