What type of ventricular rhythm is characterized by slow, regular beats?

• A. Atrial fibrillation
• B. Idioventricular rhythm
• C. Ventricular tachycardia
• D. Sinus rhythm

Answer: (B)

The correct choice identifies idioventricular rhythm, which is characterized by slow and regular ventricular beats. This rhythm typically occurs when the heart's primary pacemaker, often the sinoatrial node, fails to function adequately, allowing the ventricles to generate their own impulses. In an idioventricular rhythm, the ventricular rate usually ranges from 20 to 40 beats per minute, which is considered slow compared to the normal heart rate. The impulses originate from the ventricles, resulting in a regular rhythm despite being slower than normal, and this is what distinguishes it from other types of rhythms.

The other options mentioned represent different types of cardiac rhythms. For instance, atrial fibrillation is characterized by an irregularly irregular rhythm and lacks the regularity seen in idioventricular rhythm. Ventricular tachycardia involves a faster heart rate, often exceeding 100 beats per minute, which again contrasts sharply with the slow beats of idioventricular rhythm. Lastly, sinus rhythm is typically defined by a normal heart rate of 60 to 100 beats per minute, marked by regular intervals, which does not fit the description of the slow, regular beats associated with idioventricular rhythm.