You observe a patient rhythm with a regular rhythm and occasional wide, bizarre early beats. What are these likely?

• A. Atrial flutter
• B. Sinus arrhythmia
• C. Premature ventricular contractions
• D. Ventricular tachycardia

Answer: (C)

Premature ventricular contractions arise when an impulse starts in the ventricles rather than the SA node. They appear as early, wide, bizarre-looking QRS complexes on the ECG because ventricular conduction is different and slower than normal. When a patient’s rhythm is otherwise regular and you notice these early, wide beats interrupting it, that pattern points to ectopic ventricular activity rather than a supraventricular rhythm.

Atrial flutter would show characteristic atrial activity (sawtooth waves) and a regular or variable ventricular response, not isolated wide premature beats. Sinus arrhythmia features variation in heart rate with breathing but preserves normal, narrow QRS complexes. Ventricular tachycardia presents as a rapid, sustained, wide-complex rhythm rather than occasional extras within a regular rhythm. So the description fits premature ventricular contractions.