Which arrhythmias are absolute indications to terminate a maximal exercise test?

Which arrhythmias are absolute indications to terminate a maximal exercise test?

• A. Sustained ventricular tachycardia or other arrhythmias including second- or third-degree AV block impairing cardiac output
• B. Short runs of atrial ectopy
• C. Non-sustained VT
• D. Sinus arrhythmia

Answer: (C)

The key idea is safety: stop the test when an arrhythmia occurs that could compromise blood flow or progress to a dangerous rhythm. Non-sustained ventricular tachycardia, even though it ends on its own, signals ventricular irritability and a risk that it could escalate to a sustained VT or cause hemodynamic instability during maximal exertion. That potential for rapid deterioration makes it an absolute reason to terminate the test. By contrast, short runs of atrial ectopy and sinus arrhythmia are generally benign during peak exercise and don’t by themselves mandate stopping the test, while sustained ventricular tachycardia or high-grade AV block clearly impair cardiac output and are also reasons to stop.

The key idea is safety: stop the test when an arrhythmia occurs that could compromise blood flow or progress to a dangerous rhythm. Non-sustained ventricular tachycardia, even though it ends on its own, signals ventricular irritability and a risk that it could escalate to a sustained VT or cause hemodynamic instability during maximal exertion. That potential for rapid deterioration makes it an absolute reason to terminate the test. By contrast, short runs of atrial ectopy and sinus arrhythmia are generally benign during peak exercise and don’t by themselves mandate stopping the test, while sustained ventricular tachycardia or high-grade AV block clearly impair cardiac output and are also reasons to stop.