Systems, devices and methods for monitoring efficiency of pacing
Various systems, methods, devices and arrangements are implemented for use in pacing of the heart. One implementation is directed to methods and systems for determining a pacing location in the right ventricle of a heart and near the His bundle. A pacing signal is delivered to the location in the right ventricle. The pacing signal produces a capture of a left ventricle. Properties of the capture are monitored. Results of the monitored capture are used to assess the effectiveness of the delivered pacing signal as a function of heart function. The heart function can be, for example, at least one of a QRS width, fractionation and a timing of electrical stimulation of a late activation site of a left ventricle relative to the QRS.
1. An apparatus comprising:
a monitoring circuit configured to monitor a left ventricular contraction elicited at least partially in response to an electrostimulation delivered from a location at or near a His bundle of a subject heart; and
a processor circuit configured to:
determine an efficacy of the delivered electrostimulation using information about a subject QRS width, the information provided by the monitoring circuit and obtained during the left ventricular contraction; and
adjust an electrostimulation parameter for subsequent electrostimulation using information about the determined efficacy.
2. The apparatus of claim 1 , wherein the monitoring circuit is configured to monitor a left ventricular contraction elicited at least partially in response to an electrostimulation delivered from a location in a right ventricle of the subject heart.
3. The apparatus of claim 2 , wherein the monitoring circuit is configured to monitor a left ventricular contraction elicited at least partially in response to an electrostimulation comprising partially overlapping opposite polarity waveforms.
4. The apparatus of claim 3 , comprising a pulse generator circuit configured to generate the electrostimulation comprising the partially overlapping opposite polarity waveforms.
5. The apparatus of claim 4 , further comprising an implantable lead assembly including a first electrode and a second electrode; and
wherein the pulse generator circuit is configured to generate the electrostimulation comprising the partially overlapping opposite polarity waveforms including a first polarity waveform for delivery using the first electrode and a second polarity waveform for delivery using the second electrode.
6. The apparatus of claim 1 , wherein the processor circuit is configured to determine the efficacy using information about the left ventricular contraction and a second left ventricular contraction elicited via an electrostimulation delivered from a different site.
7. The apparatus of claim 1 , wherein the processor circuit is configured to determine the efficacy of delivered electrostimulation in response to electrostimulation delivered in a septal region of the right ventricle at or near the His bundle.
8. The apparatus of claim 1 , wherein determining the efficacy of the delivered electrostimulation includes determining a relative indication of information about a QRS width associated with the monitored contraction relative to an earlier monitored QRS width or a reference QRS width.
9. An apparatus comprising:
a monitoring circuit configured to monitor a left ventricular contraction elicited at least partially in response to an electrostimulation delivered from a location at or near a His bundle of a subject heart; and
a processor circuit configured to:
determine an efficacy of the delivered electrostimulation using information about an electrogram fractionation, the information provided by the monitoring circuit and obtained during the left ventricular contraction; and
adjust an electrostimulation parameter for subsequent electrostimulation using information about the determined efficacy.
10. The apparatus of claim 9 , wherein the monitoring circuit is configured to monitor a left ventricular contraction elicited at least partially in response to an electrostimulation delivered from a location in a right ventricle of the subject heart.
11. The apparatus of claim 10 , wherein the monitoring circuit is configured to monitor a left ventricular contraction elicited at least partially in response to an electrostimulation comprising partially overlapping opposite polarity waveforms.
12. The apparatus of claim 9 , wherein the processor is configured to determine the efficacy at least in part by the pressure generated by the heart.
13. The apparatus of claim 9 , wherein the processor is configured to determine the efficacy at least in part by a timing of activation of a late activation site of the left ventricle.
14. The apparatus of claim 9 , wherein the processor is configured to determine the efficacy at least in part by the QRS width.
15. An apparatus comprising:
a monitoring circuit configured to monitor a left ventricular contraction elicited at least partially in response to an electrostimulation delivered from a location at or near a His bundle of a subject heart; and
a processor circuit configured to:
determine an efficacy of the delivered electrostimulation using information provided by the monitoring circuit obtained during the left ventricular contraction about at least one of a pressure generated by the heart and a timing activation of a late activation site of the left ventricle; and
adjust an electrostimulation parameter for subsequent electrostimulation using information about the determined efficacy.
16. The apparatus of claim 15 , wherein the monitoring circuit is configured to monitor a left ventricular contraction elicited at least partially in response to an electrostimulation delivered from a location in a right ventricle of the subject heart.
17. The apparatus of claim 16 , wherein the monitoring circuit is configured to monitor a left ventricular contraction elicited at least partially in response to an electrostimulation comprising partially overlapping opposite polarity waveforms.
18. The apparatus of claim 15 , wherein the processor is configured to determine the efficacy at least in part by the electrogram fractionation.
19. The apparatus of claim 15 , wherein the processor is configured to determine the efficacy at least in part by the QRS width.
20. The apparatus of claim 19 , wherein determining the efficacy of the delivered electrostimulation includes determining a relative indication of information about a QRS width associated with the monitored contraction relative to an earlier monitored QRS width or a reference QRS width.