Method and apparatus for assessing left ventricular function and optimizing cardiac pacing intervals based on left ventricular wall motion

A computer readable medium programmed with instructions for performing a method for assessing left ventricular function and optimizing cardiac pacing intervals in a device programmed to operate a bi-ventricular cardiac pacing modality, comprising:

• instructions for sensing movement of a portion of a left ventricular chamber of a heart with a deployed movement transducer and for measuring a motion signal from the transducer related to the movement;
• instructions for opening a data collection window during a portion of a selected cardiac cycle phase;
• instructions for storing the motion signal throughout at least a part of the portion of the data collection window for a predetermined time interval or for more than one cardiac cycle;
• instructions fro verifying a stability characteristic of the motion signal during the predetermined time interval or for more than one cardiac cycle;
• instructions for averaging the stored motion signal;
• and
• instructions for determining a signal characteristic from the averaged stored signal that is representative of left ventricular function.

A method for optimizing cardiac pacing intervals based on left ventricular function, comprising;

• placing a motion sensor into electromechanical communication with a left ventricular lateral free wall so that the motion sensor generates a motion signal proportional to the motion of the lateral free wall;
• enabling a temporal data collection window corresponding to a selected cardiac cycle phase;
• applying a cardiac pacing stimulus delivered according to a preselected set of test pacing parameters;
• sensing the motion signal during at least a part of the temporal data collection window or during a more than one cardiac cycle for at least some members of the preselected set of test pacing parameters;
• verifying a heart rate stability condition;
• averaging the motion signal for the at least some members of the preselected set of test pacing parameters;
• determining a signal characteristic from the averaged sensed signal that is representative of relatively improved left ventricular function during each of the selected test pacing parameters;
• and
• storing a cardiac pacing timing parameter for a right ventricular pacing electrode and for a left ventricular pacing electrode that resulted in the relatively improved left ventricular function.

An apparatus for optimizing left ventricular function, comprising:

• means for sensing motion of a portion of the left ventricle and providing a motion signal;
• means for stimulating a left ventricle and a right ventricle at the same moment and at different moments;
• means for storing the sensed motion signals during a temporal window when the left ventricle and the right ventricle are stimulated at the same moment and at different moments;
• means for confirming that a stability condition for the left ventricle and the right ventricle exists;
• means for mathematically averaging the sensed motion signals for corresponding to when left ventricle and the right ventricle are stimulated at the same moment and at select different moments;
• means for determining a signal characteristic from the averaged sensed motion signals that represents a relatively improved left ventricular function;
• and
• means for storing a cardiac pacing timing parameter for a right ventricular pacing electrode and for a left ventricular pacing electrode that resulted in the relatively improved left ventricular function.