Pacing method
A method for delivering physiological pacing includes selecting an electrode implant site within an interventricular septal zone, which is in proximity to the bundle of His where pacing stimulation results in a rhythm breaking out at an intrinsic location, and wherein a ratio of sensed P-wave amplitude to sensed R-wave amplitude is less than approximately 0.5 and a pacing threshold is less than or equal to approximately 1.5 volts.
1. A method for delivering physiological pacing, the method comprising the steps of:
identifying a zone within an interventricular septum of a patient's heart, which is in proximity to the bundle of His where pacing stimulation results in a rhythm breaking out at an intrinsic location;
mapping locations within the identified interventricular septal zone according to a ratio of measured P-wave amplitude to R-wave amplitude and a pacing threshold measurement;
selecting an electrode implant site from the mapped locations where a mapped location exhibits a ratio of P-wave amplitude to R-wave amplitude that is less than approximately 0.5 and exhibits a pacing threshold is less than or equal to approximately 1.5 volts; and
positioning an electrode at the selected implant site to deliver physiological pacing,
wherein the step of mapping locations comprises measuring a P-wave amplitude and an R-wave amplitude at each mapped location to determine the ratio and measuring a pacing threshold at each mapped location.
2. The method of claim 1 , wherein the mapping step comprises:
positioning an electrode within the identified interventricular septal zone at different locations;
sensing a P-wave at each location and measuring the P-wave amplitude;
sensing an R-wave at each location and measuring the R-wave amplitude; and
pacing at each location and measuring a pacing threshold.
3. The method of claim 2 , wherein the step of positioning an electrode comprises positioning a single electrode or pair of electrodes at the different locations by varying an insertion depth.
4. The method of claim 2 , wherein the step of positioning an electrode comprises positioning a single electrode or pair of electrodes at the different locations by re-inserting the single electrode or pair of electrodes.
5. The method of claim 2 , wherein the step of positioning an electrode comprises positioning an array of electrodes and selecting a single electrode or pair of electrodes from the array at each of the different locations.
6. The method of claim 2 , wherein the step of positioning an electrode comprises inserting a single electrode or pair of electrodes by advancing the single electrode or pair of electrodes endocardially through a right atrium.
7. The method of claim 2 , wherein the step of positioning an electrode comprises inserting a single electrode or pair of electrodes by advancing the single electrode or pair of electrodes endocardially through a right ventricle.
8. The method of claim 2 , wherein the step of positioning an electrode comprises inserting a single electrode or pair of electrodes by advancing the single electrode or pair of electrodes epicardially.