Noninvasive assessment of cardiac resynchronization therapy

1. A method comprising:

(a) applying an electrode apparatus having a plurality of electrodes to a torso of a patient;

(b) introducing one of a right ventricular (RV) lead to a right ventricle or a right atrial (RA) lead to a right atrium;

(c) delivering noninvasively ultrasonic energy to a target tissue selected from a set of target tissues;

(d) in response to delivering ultrasonic energy to the cardiac tissue, receiving, with a processing unit, a torso-surface potential signal from each of a plurality of electrodes distributed on a torso of a patient for the target tissue;

(e) sensing signals from one of the RA lead and the RV lead in response to delivering ultrasonic energy;

(f) for at least a subset of the plurality of electrodes, calculating, with the processing unit, a torso-surface activation time based on the signal sensed from the electrode;

(g) repeating steps (c) through (f) for another tissue site to obtain cardiac resynchronization data;

(i) determining whether the tissue site or the another tissue site provides optimal cardiac resynchronization; and

(j) in response step (i), selecting one of the tissue site and the another tissue site that provides optimal cardiac resynchronization for locating a medical electrical lead.

2. A method of claim 1 further comprising:

(k) introducing the medical electrical lead to a coronary sinus; and

(l) moving the medical electrical lead to the coronary sinus branch that facilitates optimal cardiac resynchronization.

3. A method of claim 1 wherein the first tissue site and the another tissue site are a first coronary sinus branch and a second coronary sinus branch.

4. A method of claim 1 further comprising:

capturing one or more images of a set of coronary sinus branches in a venogram; and

presenting, by the processing unit, to a user, the set of coronary sinus branches via a display.

5. The method of claim 4 , further comprising:

acquiring P-wave signals in response to delivering ultrasonic energy to the cardiac tissue; and

timing the ultrasonic energy to PR minus a pre-specified time period following the P-wave, on successive beats.

6. A method of claim 5 wherein the PR minus a pre-specified time period being one of PR-50 ms, PR-40 ms, PR-30 ms, and PR-20 ms.

7. A method of claim 5 further comprising:

employing different PR minus a pre-specified time period in order to evaluate various degrees of fusion with intrinsic activation.

8. A method comprising:

(a) applying an electrode apparatus having a plurality of electrodes to a torso of a patient;

(b) introducing one of a right ventricular (RV) lead to a right ventricle or a right atrial (RA) lead to a right atrium;

(c) delivering noninvasively ultrasonic energy to a target tissue selected from a set of target tissues;

(d) in response to delivering ultrasonic energy to the cardiac tissue, receiving, with a processing unit, a torso-surface potential signal from each of a plurality of electrodes distributed on a torso of a patient for the target tissue;

(e) sensing signals from one of the RA lead and the RV lead in response to delivering ultrasonic energy;

(f) for at least a subset of the plurality of electrodes, calculating, with the processing unit, a torso-surface activation time based on the signal sensed from the electrode;

(g) repeating steps (c) through (f) for another tissue site to obtain cardiac resynchronization data;

(i) determining whether the tissue site or the another tissue site provides optimal cardiac resynchronization; and

(j) in response step (i), selecting one of the tissue site and the another tissue site that provides optimal cardiac resynchronization for locating a medical electrical lead.

9. The method of claim 8 further comprising:

delivering pacing pulses through a pacing electrode on the RV lead at a pre-specified interval following a P-wave to determine one of timing cardiac resynchronization therapy and VV delay.

10. The method of claim 9 wherein the pre-specified interval is used to determine timing delays for sequential biventricular pacing.

11. The method of claim 9 wherein pre-specified interval is one of 10 ms, 20 ms, 30 ms, 40 ms, 50 ms, 60 ms, 70 ms and 80 ms.

12. A method comprising:

(a) applying an electrode apparatus having a plurality of electrodes to a torso of a patient;

(b) introducing one of a right ventricular (RV) lead to a right ventricle or a right atrial (RA) lead to a right atrium;

(c) delivering noninvasively ultrasonic energy to a target tissue selected from a set of target tissues;

(d) in response to delivering ultrasonic energy to the cardiac tissue, receiving, with a processing unit, a torso-surface potential signal from each of a plurality of electrodes distributed on a torso of a patient for the target tissue;

(e) sensing signals from one of the RA lead and the RV lead in response to delivering ultrasonic energy;

(f) for at least a subset of the plurality of electrodes, calculating, with the processing unit, a torso-surface activation time based on the signal sensed from the electrode;

(g) repeating steps (c) through (f) for another tissue site to obtain cardiac resynchronization data;

(i) determining whether the tissue site or the another tissue site provides optimal cardiac resynchronization;

(j) in response step (i), selecting one of the tissue site and the another tissue site that provides optimal cardiac resynchronization for locating a medical electrical lead;

(k) introducing the medical electrical lead to a target area in a ventricle, wherein the target area is one of the endocardium and epicardium; and

(l) moving the medical electrical lead to the target area in the ventricle that facilitates optimal cardiac resynchronization.