Pacemaker system with therapy for minimizing risk of morning myocardial infarctions or arrhythmias

Abstract

There is provided a pacemaker system having the capability of providing therapy for preventing conditions likely to lead to myocardial infarction or ventricular arrhythmia during patient morning time. Specifically, a therapy is initiated before calculated patient awakening time, for raising pacing rate slowly so as to shorten QT interval to an acceptable level relative to rate at the time of patient awakening, and specifically a level that achieves satisfactory diastolic filling time. The pre-awakening therapy pacing routine is designed to overcome normal QT prolongation which occurs during sleep state, and which is delayed after patient awakening. In the event that criteria for an acceptable diastolic filling time are not met at or after patient awakening, the pacemaker takes steps to control rate, such as ceasing synchronous pacing and limiting automatic rate response.