Patent ID: 8019416
Filing Date: 2011-09-13
Classification: A61N

Abstract:
1. A cardiac device, comprising: sensing circuitry for receiving electrogram signals representing atrial and ventricular activity; pacing circuitry for delivering atrial and ventricular pacing pulses; a controller programmed to operate the device in either a normal operating mode or AV delay reduction (AVDR) mode, wherein the normal mode and the AVDR modes are atrial-triggered or AV sequential pacing modes in which paces are delivered to one or more ventricular sites after an AV delay interval with respect to an atrial sense or pace; wherein, in the AVDR mode, the controller is programmed to deliver paces to the one or more ventricular sites using an AV delay interval that is shorter than the AV delay interval used in the normal mode; wherein the controller is programmed to measure a patient's intrinsic atrio-ventricular interval and compute the AV delay interval used in the AVDR mode as a specified percentage thereof in order to reduce atrial preloading of the ventricles during diastole; wherein the controller is programmed to intermittently switch from the normal operating mode to the AVDR mode according to a one or more specified entry conditions and switch from the AVDR mode to the normal operating mode according to one or more specified exit conditions; a posture sensor interfaced to the controller; wherein the controller is programmed to determine a patient's posture and use a determination that the patient is supine as an exit condition for exiting the AVDR mode.