Pacemaker with evoked response detection by using differential sensing between two unipolar electrodes

摘要

A heart stimulator, operable for single-chamber and/or dual- chamber pacing, includes first and second electrical leads connected to a pulse generator and each terminating in an electrode, the electrodes being disposed respectively in the atrium and the ventricle. A differential detector is connected to the first and second leads and detects cardiac activity between the atrial electrode and the ventricular electrode. A correlation detector is connected between the pacemaker housing and one of the atrial or ventricular electrodes, and generates a correlation signal identifying whether the cardiac activity detected by the cardiac activity detector arose in the atrium or in the ventricle. The outputs of the differential detector and the correlation detector are supplied to a logic circuit which determines therefrom whether a stimulation pulse emitted by the pulse generator resulted in an evoked response in the heart.