Adjustment of the atrial sensitivity and of the atrial stimulation energy in an active implantable medical device such as double chamber cardiac pacemaker

摘要

An active implantable medical device, such as a double chamber pacemaker or defibrillator or cardiovertor, having an improved adjustment of atrial sensitivity and of atrial stimulation energy. This device includes control algorithms for suspecting a loss of atrial detection and/or atrial capture that operates by analysis of a sequence of detected stimulations and ventricular and atrial detections. The following conditions are detected: an absence of ventricular activity post-atrial stimulation; and/or a lengthening, beyond a given limit, of the atrio-ventricular conduction delay over a predetermined number of successive cardiac cycles; and/or an occurrence of an atrial detection consecutive to an atrial stimulation over a predetermined number of successive cardiac cycles; and/or a ventricular extrasystole; and/or reduction, below a given limit, of a delay between atrial stimulation and ventricular detection; and/or the passage of an atrial detection to an atrial stimulation with concomitant reduction, below a given limit, of the delay between atrial event and ventricular detection. The atrial detection threshold and/or the atrial stimulation energy are adjusted, preferably stepwise, according to the detected conditions to provide improved patient care.