Implantable medical apparatus for stimulating a heart
AssigneeSiemens Aktiengesellschaft
InventorIndra Nigam
Life of this patent
Estimating the term…
Abstract
An implantable medical apparatus delivers, in order to induce or terminate a tachyarrhythmia in a heart, a sequence consisting of several stimulation pulses having a time interval T.sub.t between each stimulation pulse. The first stimulation pulse is delivered after the lapse of a time interval T.sub.t, triggered by a spontaneous heart event If a detector in the apparatus detects a spontaneous heart event during any of the time intervals T.sub.t between the stimulation pulses during the attempt of inducing or terminating, the next stimulation pulse will be delivered after the lapse of the time interval T.sub.t from the detected spontaneous heart event. The apparatus also limits the duration of the sequence.
Claims12
An implantable medical device for stimulating a heart comprising:
- stimulation pulse generator means for generating and delivering stimulation pulses in vivo to cardiac tissue;
- activatable detector means for, when activated, detecting spontaneous cardiac events;
- control means connected to said stimulation pulse generator means and to said detector means for inducing or terminating a tachyarrhythmia by causing said stimulation pulse generator means, following a time interval after the detection of a spontaneous cardiac event by said detector means, to deliver a sequence of a predetermined number of stimulation pulses with said time interval between each pulse, and said control means activating said detector means during delivery of said sequence;
- said control means including time counter means for beginning a time count upon the detection of each spontaneous cardiac event by said detector means and said control means causing said stimulation pulse generator means to deliver a stimulation pulse when said time counter means reaches a time count equal to said interval;
- means for resetting said time counter means upon the detection of another spontaneous cardiac event during said time interval by said detector means and upon the delivery of a stimulation pulse by said stimulation pulse generator means;
- and
- said control means including means for limiting the duration of said pulse sequence.
A method for inducing or terminating tachycandia comprising the steps of:
- detecting in vivo spontaneous cardiac events;
- delivering in vivo, following a time interval after detecting a spontaneous cardiac event, a sequence of a predetermined number of stimulation pulses with said time interval between each pulse;
- activating a time counter to begin a time count upon the detection of each spontaneous cardiac event;
- delivering a stimulation pulse when said time count reaches a value equal to said time interval;
- resetting said time counter upon the detection of another spontaneous cardiac event during said time interval and upon the delivery of a stimulation pulse;
- and
- limiting the duration of said pulse sequence.
Dependencies are inferred from the claim text.