What is a typical clinical picture feature of sinus arrhythmia?

What is a typical clinical picture feature of sinus arrhythmia?

• A. Irregular pulse
• B. Regular pulse
• C. Palpitations always
• D. Syncope only

Answer: (A)

Respiratory sinus arrhythmia is a normal fluctuation in heart rate tied to the breathing cycle. Inhalation speeds the heart a bit, exhalation slows it, so the intervals between beats vary in a rhythmic way. This makes the pulse irregular in timing, even though the rhythm is sinus and the heart’s conduction is fine. It’s especially common in children and young healthy adults and is usually asymptomatic. So the hallmark feature is an irregular pulse that tracks respiration, not a consistently regular pulse and not typical symptoms like palpitations or syncope. On ECG you’d still see a normal P waves with a cyclic variation in R‑R intervals corresponding to breathing.

Respiratory sinus arrhythmia is a normal fluctuation in heart rate tied to the breathing cycle. Inhalation speeds the heart a bit, exhalation slows it, so the intervals between beats vary in a rhythmic way. This makes the pulse irregular in timing, even though the rhythm is sinus and the heart’s conduction is fine. It’s especially common in children and young healthy adults and is usually asymptomatic. So the hallmark feature is an irregular pulse that tracks respiration, not a consistently regular pulse and not typical symptoms like palpitations or syncope. On ECG you’d still see a normal P waves with a cyclic variation in R‑R intervals corresponding to breathing.