Which term denotes normal sinus rhythm?

• A. Murmur
• B. T-wave
• C. QRS complex
• D. NSR

Answer: (D)

Normal sinus rhythm is the standard heart rhythm that starts at the sinoatrial node and follows the normal conduction pathway, producing a P wave before every QRS complex, with a stable PR interval and a typical rate. The term used to denote this normal rhythm is normal sinus rhythm, abbreviated NSR. A murmur is an abnormal heart sound from turbulent flow, not a rhythm. The T-wave is a waveform representing ventricular repolarization on the ECG, not a rhythm label. The QRS complex reflects ventricular depolarization on the ECG, but it itself isn’t the name of the rhythm. So the term that denotes normal sinus rhythm is NSR.