Patent ID: 6339723
Filing Date: 2002-01-15
Classification: A61N

Abstract:
An implantable cardiac stimulation device for stimulating a patient's heart through a first electrode implanted in electrical contact with an atrium of the patient's heart, the implantable cardiac stimulation device comprising:a pulse generator adapted to be electrically coupled to the first electrode and configured to generate atrial stimulation pulses at a programmed amplitude level and rate for stimulating the patient's heart; an atrial detection circuit adapted to be electrically coupled to the first electrode for determining the presence or the absence of an evoked response to a stimulation pulse from the pulse generator; and a controller coupled to the pulse generator for periodically determining a capture threshold level suitable for causing an evoked response to an atrial stimulation pulse, wherein the controller causes the pulse generator to deliver a first primary atrial stimulation pulse at a first amplitude level, a secondary atrial stimulation pulse at a second amplitude level an atrial delay time after the first primary atrial stimulation pulse, and a second primary atrial stimulation pulse at a third amplitude level delayed by a time period defining a cardiac rate in excess of the intrinsic cardiac rate, whereby the potential occurrence of fusion beats is minimized.