Which statement best describes the relationship between P waves and QRS complexes in a healthy rhythm?

Which statement best describes the relationship between P waves and QRS complexes in a healthy rhythm?

• A. There are multiple QRS for every P
• B. Each P wave is followed by a single QRS complex
• C. There is no P wave associated with QRS
• D. P waves occur only after T waves

Answer: (B)

In a healthy rhythm, the atrial impulse and the ventricular impulse stay in a one-to-one sequence: each P wave represents atrial depolarization and is followed by a single QRS complex representing ventricular depolarization. This demonstrates proper AV conduction and a consistent timing (the PR interval is regular, and the QRS is narrow). That’s why the statement “Each P wave is followed by a single QRS complex” is the best description. If you saw multiple QRS complexes for one P, or no P wave at all with a QRS, or P waves appearing after the T wave, you’d be looking at an abnormal rhythm, not a healthy sinus rhythm.

In a healthy rhythm, the atrial impulse and the ventricular impulse stay in a one-to-one sequence: each P wave represents atrial depolarization and is followed by a single QRS complex representing ventricular depolarization. This demonstrates proper AV conduction and a consistent timing (the PR interval is regular, and the QRS is narrow). That’s why the statement “Each P wave is followed by a single QRS complex” is the best description. If you saw multiple QRS complexes for one P, or no P wave at all with a QRS, or P waves appearing after the T wave, you’d be looking at an abnormal rhythm, not a healthy sinus rhythm.