Reverse hysteresis and mode switching for intermittent pacing therapy

摘要

Cardioprotective pre-excitation pacing may be applied to stress or de-stress a particular myocardial region delivering of pacing pulses in a manner that causes a dyssynchronous contraction. Such dyssynchronous contractions are responsible for the desired cardioprotective effects of pre-excitation pacing. A method and device for applying reverse hysteresis and mode switching to the delivery of such cardioprotective pacing are described.

主权项

1. A cardiac device, comprising:
one or more sensing amplifiers for sensing electrical cardiac activity through one or more sensing channels; one or more pulse generators for delivering pacing pulses to one or more myocardial sites through one or more pacing channels; an exertion level sensor for measuring exertion level; a controller programmed to operate the device in either a normal operating mode or an intermittent pacing therapy (IPT) mode; wherein, in the IPT mode, the controller is programmed to deliver paces to the one or more myocardial sites using a pacing mode that results in some degree of dyssynchrony as compared with the normal operating mode; wherein the controller is programmed to intermittently switch to the IPT mode that delivers ventricular pacing pulses with an escape interval initially set to a specified IPT value; wherein the controller is programmed to switch to a non-atrial tracking IPT mode if the measured exertion level is below a specified value and switch to an atrial tracking IPT mode otherwise; wherein, when operating in the IPT mode, the controller is further programmed to monitor for senses that inhibit the ventricular pacing pulses and, after a specified number of such senses have occurred, further shorten the escape interval from the IPT value; and, wherein the controller is further programmed to continue operating in the IPT mode without shortening the escape interval if the escape interval has been shortened to a specified minimum limit value.