SA Node Rate — FRCA Primary MCQ
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Correct answer: D — 60-100 bpm
SA node: 60-100 bpm / AV node: 40-60 bpm / His-Purkinje: 20-40 bpm. The SA node fires fastest and is therefore the primary pacemaker. Vagal tone normally suppresses the rate to approximately 60-70 bpm at rest.
Reference: Power Kam 2018 Principles of Physiology for the Anaesthetist