Patent ID: 8332030

Claim:
A device for providing pacing therapy, the device comprising: an atrial lead for sensing electrical activity in an atrium; a ventricular lead for sensing electrical activity in a ventricle and for delivering electrical pulses to the ventricle; sensing circuitry connected to the atrial and ventricular leads for sensing depolarizations in the atrium and ventricle, respectively; pulse generation circuitry connected to the ventricular lead for delivering pacing pulses to the ventricle, respectively; and control circuitry responsive to sensed atrial depolarizations, for detecting atrial arrhythmias and for controlling the pulse generation circuitry in a mode in which the pulse generation circuitry delivers an atrial synchronized pulse to the ventricular lead in response to each atrial depolarization and causing the pulse generation circuitry, in response to a detected atrial arrhythmia, to deliver atrial synchronized pacing pulses to the ventricular lead in response only to selected atrial depolarizations, wherein the control circuitry determines a desired ratio of atrial depolarizations to ventricular paced pulses based on a beat rate of the atrial arrhythmia and a preferred ventricular beat rate and causes the pulse generation circuitry to deliver atrial synchronized pulses to the ventricular lead in response to detection of a number of atrial depolarizations corresponding to the desired ratio.