Patent ID: 7206634

Claim:
A cardiac device, comprising: an atrial sensing channel; a first stimulation channel configurable for stimulating the right or left ventricle; a controller for controlling the delivery of stimulus pulses through the stimulation channels in accordance with a programmed mode, wherein the controller is programmed to stimulate the right or left ventricle in an atrial tracking mode with a specified atrio-ventricular interval between an atrial sense and a ventricular stimulus; a left atrial accelerometer adapted for contacting a wall of the left atrium in order to sense mechanical contraction of the left atrium; a left ventricular accelerometer configurable for sensing mechanical contraction of the left ventricle; wherein the controller is programmed to measure the time interval between sensed mechanical contractions of the left atrium and the left ventricle as sensed by the accelerometers during a cardiac cycle; and, wherein the controller is further programmed to adjust the atrio-ventricular interval until the measured time interval between contractions of the left atrium and left ventricle equals a specified value (T 1 ).