Capture beat
Also calledcaptured beat · sinus capture · capture complex
Definition
During a wide-complex ventricular rhythm with AV dissociation (ventricular tachycardia or an idioventricular rhythm), a beat produced when an atrial impulse gets through the AV junction and depolarizes the ventricles, so its QRS differs from the surrounding wide complexes; if the atrial impulse depolarizes only part of the ventricles, the result is a fusion beat instead. Because capture beats come from AV conduction of dissociated atrial impulses, their presence (like fusion beats) demonstrates AV dissociation and strongly suggests ventricular tachycardia in a wide-complex tachycardia.
Clinical noteCapture beats are relatively rare and diagnostically valuable, but their absence does not exclude VT.
Sources
- Wellens HJ, Bär FW, Lie KI. The value of the electrocardiogram in the differential diagnosis of a tachycardia with a widened QRS complex. Am J Med. 1978;64(1):27-33. doi.org/10.1016/0002-9343(78)90176-6
- Samesima N, God EG, Kruse JCL, et al. Brazilian Society of Cardiology guidelines on the analysis and issuance of electrocardiographic reports - 2022. Arq Bras Cardiol. 2022;119(4):638-680. doi.org/10.36660/abc.20220623
Last reviewed 2 October 2026. Every definition in the EKG Dictionary cites the guideline, consensus statement or original paper it comes from.