Trending of conduction time for optimization of cardiac resynchronization therapy in cardiac rhythm management system

Abstract

A method of optimizing cardiac resynchronization therapy delay over a patient's full range of activity for use in operating an implantable cardiac pacing device and such a device are disclosed. The method includes measuring selected conduction time between selected sites in the heart for a plurality of beats and logging the values on a periodic repeating programmable basis to produce cumulative data and constructing a current template of conduction time in relation to one or more other sensed parameters of interest over a desired range of patient activity levels. The current template is used to derive suggested optimum pacing timing.

Description

BACKROUND OF THE INVENTION [0001] I. Field of the Invention [0002] The present invention relates generally to the operation of cardiac rhythm management systems and, more particularly, to the optimization of cardiac resynchronization therapy based on templates produced pursuant to data exhibiting trending of selected conduction times within the heart. [0003] II. Related Art [0004] Early cardiac pacemakers were used primarily to pace the heart when a normal conduction path from the sino-atrial (SA) node of the heart to the atrial-ventricular (AV) node or from the AV node to the ventricles was interrupted. In accordance with these events, the pacemaker was called upon to deliver ventricular stimulating pulses to maintain a pre-determined heart rate. More recently, pacemaker technology has become greatly advanced and sophisticated. For example, rate adaptive pacing has been used to vary the pre-determined rate in accordance with parameters indicative of patient activity level. In addit...

AI Technical Summary

Benefits of technology

[0010] The present invention provides a unique comprehensive approach to the optimization of resynchronization therapy in cardiac pacing for an individual, based on optimizing the pacing delay between two or more sites within the heart, such as atrio-ventricular (AV), ventricular-ventricular (V-V), right ventricular-left ventricular (RV-LV), right atrial-left atrial (RA-LA), etc. This is accomplished by trending a stream of data measuring a conduction time parameter of interest between the selected two points within the heart in relation to one or more sensed factors or parameters of interest such as cycle length (R-R), activity level and minute ventilation (MV), etc. Data is sensed and stored until a sufficient amount of conduction time data is collected along with other sensor data to construct a conduction time versus parameter-of-interest template which, in turn, provides a basis for optimizing the pacing delay between the corresponding pacing sites by using a developed empirical mathematical functional relationship.

Problems solved by technology

This technique is preferably avoided because implementation of such systems require complicated measurement and none have been adapted to provide automatic optimization of cardiac performance parameters based on the measurements.

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