What is ventricular tachycardia?

• A. A slow rhythm originating in the atria
• B. A fast rhythm originating in the atria
• C. A fast rhythm originating in the ventricles
• D. A slow rhythm originating in the ventricles

Answer: (C)

Ventricular tachycardia is a rapid heart rhythm that starts in the ventricles, the lower chambers of the heart. Because the impulse arises in the ventricles rather than the atria, the rate climbs quickly—often above 100 beats per minute—and the ECG shows wide, abnormal-looking QRS complexes due to the abnormal path the impulse takes through ventricular muscle. This is different from rhythms that originate in the atria, which are supraventricular tachycardias and usually have narrower QRS complexes unless there’s another conduction problem. It’s also distinct from slow rhythms, where the heart rate is reduced rather than accelerated.