Capture management in a left ventricular leadless pacing device that includes determining an intrinsic P-wave of a sensed cardiac signal, sensing an electromechanical signal from an electromechanical sensor of the pacing device, and determining an intrinsic electromechanical atrioventricular interval of the sensed electromechanical signal in response to the sensed P-wave. Ventricular pacing is delivered via the one or more electrodes of the pacing device, and a ventricular pacing (V-pace) event is determined in response to the delivered ventricular pacing, and a V-pace to electromechanical response interval is determined in response to the V-pace event. A determination as to capture is detected is made in response to the intrinsic electromechanical atrioventricular interval and the V-pace to electromechanical response interval, and a pacing parameter is determined in response to determining whether capture is detected.
