System and method for controlling a heart stimulator

摘要

In a system and method for controlling an implantable stimulator capable of producing pacing pulses to be delivered to cardiac tissue, as well as vagal stimulation pulses to be delivered to vagus nerve sites, upon detection of a premature cardiac event, such as a premature ventricular or atrial contraction, a simulated heart rate turbulence (HRT) procedure is applied if the intrinsic heart rate turbulence is weakened or absent. The simulated HRT includes a first phase in which the heart rate is increased, from the existing level, for a number of heart beats, a second phase in which the heart rate is decreased for a number of heart beats, and an optional third phase in which the heart rate is returned to said existing level.

主权项

1. An implantable heart stimulator comprising:
a cardiac pulse generator that generates and emits pacing pulses; a cardiac lead connected to said cardiac pulse generator and configured to deliver said pacing pulses to cardiac tissue in at least one ventricle of a heart; at least one cardiac lead carrying an electrode configured to detect electrical signals in the heart representative of cardiac contractions; a vagal pulse generator that generates and emits vagal stimulation pulses; at least one vagal lead configured to deliver said vagal stimulation pulses to a vagus nerve site; a signal processing circuit configured to receive the electrical signals indicative of cardiac contractions and to process the received signals to determine therefrom whether a premature cardiac contraction has occurred, the signal processing circuit being further configured to determine whether heart rate turbulence is present in the received electrical signals in response to the detection of the occurrence of said premature cardiac contractions; and a controller connected to said signal processing circuit to receive said output therefrom, said controller being configured to initiate a heart rate turbulence procedure to mimic heart rate turbulence by controlling said cardiac pulse generator to increase a rate of emission of said pacing pulses to initially accelerate the heart rate of said heart to an accelerated rate above an existing heart rate upon an occurrence of said premature contraction and the failure to detect heart rate turbulence, and to subsequently decelerate said heart rate to a decelerated rate below said existing heart rate by controlling said vagal stimulation pulse generator to produce a vagal response that decelerates the heart rate.