Abstract: An active implantable medical device, in particular a pacemaker, defibrillator, cardiovertor, or a multisite device including detection of a risks of a fusion situation. This device is of the double chamber type, and it detects atrial and ventricular events, provides atrial and ventricular stimulation, and delivers a ventricular stimulation pulse after expiration a programmed atrio-ventricular delay (AVD) following the detection of an atrial event (P, A), and in the absence of detection of a ventricular spontaneous event (R) within the AVD. A fusion situation is detected based on an analysis of a sequence of successive cardiac cycles for which the atrio-ventricular delay is modified from one cycle to the next (AVD, AVD+31, AVD+63).

Abstract: An active implantable medical device, in particular a pacemaker, defibrillator, or cardiovertor having an automatic adjustment of the stimulation pulse level. This device delivers to the heart stimulation pulses of low energy for the treatment of the cardiac disorders, which stimulation pulses present a predetermined amplitude and duration (width). The amplitude of the stimulation pulses can be automatically adjusted, a capture threshold is measured at predetermined intervals, and the measured capture threshold value is used as a basis for the adjustment of the stimulation pulse amplitude. The amplitude adjustment includes a validation of the measured capture threshold value, suitable to operate a coherence test between the last capture threshold value measured and at least one of the corresponding capture threshold values previously measured. The adjustment of the stimulation pulse amplitude level is then inhibited in the event of positive result of the coherence test.