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CRT in Narrow QRS - Contraindicated — EECC MCQ

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ModerateCardiac DevicesCRT in Narrow QRS - ContraindicatedEECC

A 65-year-old man with HFrEF (LVEF 28%) and QRS duration of 110 ms (narrow) is being considered for CRT. He is in NYHA class III despite optimal GDMT. Is CRT recommended?

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Correct answer: B — CRT is not recommended for narrow QRS (<130 ms) based on the EchoCRT trial which showed harm

The EchoCRT trial (2013) definitively demonstrated that CRT in HFrEF patients with narrow QRS (<130 ms) is harmful — it increased mortality compared with ICD alone, even when echocardiographic mechanical dyssynchrony was present. The ESC Pacing Guidelines and HF Guidelines therefore restrict CRT to patients with QRS ≥130 ms (strongest indication for QRS ≥150 ms with LBBB morphology, Class I LOE A). The presence of echocardiographic dyssynchrony should NOT be used to select narrow-QRS patients for CRT. For this patient with a narrow QRS, CRT is not indicated; ICD alone may be considered if he meets primary prevention criteria.

Reference: ESC (2021): Guidelines on Cardiac Pacing and CRT; EchoCRT Trial