초록 ▼

An improved device and method for performing automatic capture/threshold determination that is particularly useful in an implantable cardiac stimulation device. While conventional devices use a fixed shortening of the AV/PV delays during automatic capture/threshold determinations, any shortening can

An improved device and method for performing automatic capture/threshold determination that is particularly useful in an implantable cardiac stimulation device. While conventional devices use a fixed shortening of the AV/PV delays during automatic capture/threshold determinations, any shortening can unnecessarily cause discomfort to patients with heart blocks and unnecessarily diminish the atrial kick for other patients. Accordingly, embodiments of the present invention periodically measure the AR/PR conduction times and tabulate and/or otherwise process this data. Preferably, these measured conduction times are also correlated with the current heart rate. Finally, when an automatic capture/threshold determination occurs, this measured conduction data, which corresponds to this patient, is used to adjust the AV/PV delays while minimizing patient discomfort and adverse hemodynamic effects. Alternatively, the AV/PV delays may be manually programmable by a medical practitioner.

대표청구항 ▼

1. An implantable cardiac stimulation device configured for sensing an atrial event through a first electrode to receive electrical signals from atrial tissue of a patient's heart and for stimulating the ventricle of a patient's heart through a second electrode implanted in electrical contact with v

1. An implantable cardiac stimulation device configured for sensing an atrial event through a first electrode to receive electrical signals from atrial tissue of a patient's heart and for stimulating the ventricle of a patient's heart through a second electrode implanted in electrical contact with ventricular tissue of the patient's heart, the stimulation device comprising:a first detection circuit coupled to the first electrode and configured to receive cardiac signals for determining the presence or absence of an atrial event; a ventricular pulse generator electrically coupled to the second electrode and configured to generate ventricular stimulation pulses at a controlled energy level to thereby stimulate the ventricle of the patient's heart; a second detection circuit electrically coupled to the second electrode and configured to receive cardiac signals for determining the presence or absence of a ventricular event wherein the ventricular event alternatively includes an evoked response to each of the stimulation pulses or an intrinsic ventricular depolarization; a controller coupled to the pulse generator for increasing the ventricular stimulation pulse energy level in response to the absence of at least one evoked response to a ventricular stimulation pulse; and whereby the controller periodically causes the ventricular pulse generator to generate ventricular stimulation pulses a threshold detection delay period after an atrial event and whereby the threshold detection delay period is determined based upon a measured time between an atrial event and an intrinsic ventricular depolarization.