RACE II Lenient Rate Control — EECC MCQ

Correct answer: D — Resting heart rate <110 bpm — the RACE II trial showed lenient rate control (<110 bpm at rest) was non-inferior to strict control (<80 bpm) for cardiovascular outcomes; the 2024 ESC AF Guidelines recommend an initial lenient target with stricter control if symptoms persist

RACE II (2010) randomised 614 patients with permanent AF to lenient rate control (resting HR <110 bpm) vs strict rate control (resting HR <80 bpm AND HR <110 during moderate exercise). Results: lenient control was non-inferior for the composite of CV death, HF hospitalisation, stroke, systemic embolism, major bleeding, and life-threatening arrhythmic events. The lenient group required fewer visits and medications with comparable outcomes. The 2024 ESC AF Guidelines recommend: (1) initial target: resting HR <110 bpm (lenient — Class IIa); (2) if symptoms persist: tighten to <80 bpm (stricter control — Class IIa); (3) individualise based on symptom response, LV function, and tolerability. This patient's HR of 72 bpm on metoprolol is well below both targets — if asymptomatic, dose reduction could be considered to reduce fatigue/bradycardia-related symptoms.

Reference: ESC (2024): AF Guidelines; RACE II Trial