Patent ID: 8103344
Filing Date: 2012-01-24
Classification: A61N

Abstract:
1. A device for a dual chamber cardiac stimulator for controlling the delivery of stimulation pulses to a human heart, wherein the stimulator is connectable to a lead arrangement arranged for sensing atrial electrical activity and atrial mechanical activity, the device comprising processing circuitry configured to: receive a first signal representative of atrial electrical activity, and a second signal representative of atrial mechanical activity representative of atrial mechanical contractions; determine if said electrical activity indicates atrial tachyarrhythmia, if said mechanical activity indicates atrial tachyarrhythmia, and if a combination of said electrical and mechanical activity indicates atrial tachyarrhythmia; calculate, from said second signal, the frequency of mechanical activity, and compare said calculated mechanical frequency with a threshold value for determining if atrial tachyarrhythmia is indicated, compare said calculated mechanical frequency with an upper threshold value, with a lower threshold value, or both, determine that atrial tachyarrhythmia based on said mechanical activity is indicated if the calculated mechanical frequency is higher than said upper threshold value, or lower than said lower threshold value; and effectuate a mode switch, as soon as at least said indication of atrial tachyarrhythmia based on said mechanical activity, from a first mode where delivery of ventricular stimulation pulses is synchronized to detected atrial events, to a second mode where delivery of ventricular stimulation pulses is unsynchronized to detected atrial events.