Patent ID: 7801609

Claim:
A cardiac rhythm management device, comprising: a sensing amplifier for sensing depolarizations from the right ventricle; pulse generation circuitry for pacing the right and left ventricles; a controller for controlling the delivery of paces in accordance with a programmed pacing mode; wherein the controller is programmed to: detect a tachyarrhythmia when a time interval between successive right ventricular senses is below a specified tachyarrhythmia rate threshold interval; pace the right and left ventricles upon expiration of an escape interval such that the left ventricle is paced before the right ventricle is paced at a pacing instant as defined by a negative offset interval, wherein the escape interval is reset by a right ventricular pace or sense and wherein a pacing interval is defined as the interval between a right ventricular pace or sense and expiration of an escape interval; render the right ventricular sensing channel refractory for a selected cross-chamber sensing refractory period upon delivery of a left ventricular pace during which no sensing of the right ventricle occurs; and, enter a reversion mode for decreasing a lower limit rate for tachyarrhythmia detection when a maximum tachyarrhythmia rate threshold interval, defined as the pacing interval minus the negative offset interval, is less than a specified limit value.