Patent ID: 8131366
Filing Date: 2012-03-06
Classification: A61N

Abstract:
1. A biventricular heart stimulator for stimulating both ventricles of a human heart, comprising a pulse generator for delivering stimulation pulses of varying amplitudes, electrode leads for transmitting stimulation pulses from the pulse generator to a first and to a second of said ventricles, and for transmitting electric signals from the ventricles of the heart to the heart stimulator; a control unit for controlling the pulse generator, said control unit being configured to control the delivery of said pulses such that stimulation pulses in a single heart beat cycle are respectively first delivered to the first of said ventricles and then to the second of said ventricles; a sensing circuit configured to check for capture or loss of capture in one of said ventricles in response to delivered stimulation pulses, said sensing circuit being controlled by said control unit and arranged to receive said electric signals transmitted by said electronic leads; the control unit being configured to perform, as a result of loss of capture determined in said one ventricle by said sensing circuit, a preventive measure for prevention of loss of capture in the other ventricle, as a result of at least two successive losses of capture; said sensing circuit being also configured to check for capture or loss of capture in the other ventricle, and said control unit being configured to effect an immediate check for capture in the other ventricle as said preventive measure; and said control unit being further configured to perform threshold searches for determining a threshold value for the amplitude of a stimulation pulse that is required for effectuating capture, and for setting the pulse amplitude of the stimulation pulses to a value exceeding said determined threshold value by a selected margin, and to perform such a threshold search in said other ventricle as a result of determined loss of capture in said other ventricle, as a result of said at least two successive losses of capture.