Apparatus and method for treating ventricular tachyarrhythmias
First Claim
1. A method, comprising:
- sensing atrial events and ventricular events;
calculating an average atrial rate from the sensed atrial events;
determining an average ventricular rate from sensed ventricular events;
determining ventricular interval rates from pairs of consecutively sensed ventricular events in a detection window, wherein the detection window is a predetermined series of ventricular events;
comparing each of the ventricular interval rates in the detection window to a lower rate threshold value for each of two or more rate zones, wherein each of the two or more rate zones include a ventricular tachycardia therapy deliverable when the detection window is satisfied;
classifying a ventricular interval rate of the ventricular interval rates as a fast ventricular interval for a rate zone of the two or more rate zones when the ventricular interval rate is equal to or greater than the lower rate threshold value of the rate zone;
declaring the detection window satisfied when a first predetermined percentage of the ventricular interval rates in the detection window are classified as fast ventricular intervals for the rate zone of the two or more rate zones;
starting a duration time interval once the detection window is declared satisfied;
inhibiting ventricular tachycardiac therapy with at least one programmable detection enhancement algorithm during a sustaned duration time period, wherein the sustained duration time period is started at the expiration of the duration time interval; and
applying the inhibited ventricular tachycardia therapy for the rate zone when the average ventricular rate becomes greater than the average atrial rate by at least the bias factor during the sustained duration time period.
0 Assignments
0 Petitions
Accused Products
Abstract
A system and method for selectively treating a ventricular tachycardia based on sensed atrial and ventricular intervals from the patient'"'"'s heart. A detection window of the ten most recent atrial and ventricular intervals are analyzed for the occurrence of either tachycardia or fibrillation. When a majority of the sensed intervals are satisfied, the apparatus starts a duration time interval. Ventricular intervals and atrial intervals are compare, ventricular interval greater than the atrial interval by a bias factor the system delivers tachycardia therapy to the heart. Alternatively, the method withholds tachycardia therapy to the heart when the atrial rate is classified as atrial fibrillation and the ventricular response is unstable.
205 Citations
9 Claims
-
1. A method, comprising:
-
sensing atrial events and ventricular events; calculating an average atrial rate from the sensed atrial events; determining an average ventricular rate from sensed ventricular events; determining ventricular interval rates from pairs of consecutively sensed ventricular events in a detection window, wherein the detection window is a predetermined series of ventricular events; comparing each of the ventricular interval rates in the detection window to a lower rate threshold value for each of two or more rate zones, wherein each of the two or more rate zones include a ventricular tachycardia therapy deliverable when the detection window is satisfied; classifying a ventricular interval rate of the ventricular interval rates as a fast ventricular interval for a rate zone of the two or more rate zones when the ventricular interval rate is equal to or greater than the lower rate threshold value of the rate zone; declaring the detection window satisfied when a first predetermined percentage of the ventricular interval rates in the detection window are classified as fast ventricular intervals for the rate zone of the two or more rate zones; starting a duration time interval once the detection window is declared satisfied; inhibiting ventricular tachycardiac therapy with at least one programmable detection enhancement algorithm during a sustaned duration time period, wherein the sustained duration time period is started at the expiration of the duration time interval; and applying the inhibited ventricular tachycardia therapy for the rate zone when the average ventricular rate becomes greater than the average atrial rate by at least the bias factor during the sustained duration time period. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
Specification