Sinus Tachycardia is commonly seen in which population?

• A. Children and young adults
• B. Elderly
• C. Athletes
• D. Post-MI patients

Answer: (A)

Sinus tachycardia reflects a normal SA‑node–driven speeding of the heart in response to increased demand, with a regular rhythm and normal P waves. It is most commonly seen in children and young adults because their resting heart rates are naturally higher than those of adults. A child or teen can have a resting pulse well over typical adult values, and with fever, activity, or stress, it easily becomes tachycardic while the rhythm remains sinus. Athletes, due to high vagal tone, usually have lower resting heart rates, so resting sinus tachycardia is less typical for them. While elderly or post‑MI patients can experience tachycardia, it’s usually due to illness, medications, or other factors rather than the usual pediatric pattern.