Delivery of cardiac pacing therapy for cardiac remodeling
A method and device apparatus to deliver a pacing therapy capable of remodeling a patient's heart over a period of time that includes monitoring one or more parameters in response to a delivered cardiac remodeling pacing, determining whether the cardiac remodeling pacing has an effect on cardiac normalization in response to the monitoring, and adjusting the cardiac remodeling pacing in response to the determined effect on cardiac normalization. The method and device may also perform short-term monitoring of one or more parameters in response to the delivered cardiac remodeling pacing, monitor one or more long-term parameter indicative of a long-term effect of the delivered cardiac remodeling pacing, determine the long-term effect of the delivered cardiac remodeling pacing on cardiac normalization in response to the monitoring, and adjust the cardiac remodeling pacing in response to one or both of the short-term monitoring and the determined long-term effect on cardiac normalization.
1. A method comprising:
delivering cardiac remodeling pacing when the patient is inactive by delivering electrical pulses to the patient's heart to increase the patient's heart rate to stimulate one or more of dilation of chambers and muscular endurance of the patient's heart during a plurality of sessions over a period of time, wherein the period of time is greater than or equal to one week, wherein the cardiac remodeling pacing is suspended between each of the plurality of sessions;
monitoring one or more parameters, wherein at least one of the one or more parameters is indicative of an effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart;
determining a long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time, wherein the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart is indicative of the effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart over the period of time;
adjusting the cardiac remodeling pacing during a present session of the plurality of sessions in response to the one or more parameters monitored during the present session of the plurality of sessions; and
adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart.
2. The method of claim 1 , wherein monitoring the one or more parameters comprises sensing a cardiac signal during delivery of the cardiac remodeling pacing,
wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises:
determining QRS durations over the period of time based on the sensed cardiac signal, and
determining whether the QRS durations are increasing over the period of time;
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises adjusting the cardiac remodeling pacing in response to determining that the QRS durations are increasing over the period of time.
3. The method of claim 1 , the method further comprising:
dividing each session of the plurality of sessions during which the cardiac remodeling pacing is delivered into predetermined time segments,
wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises determining, for each of the predetermined time segments, whether AV-block is occurring,
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises inhibiting the cardiac remodeling pacing delivery during the predetermined time segments for which AV-block was determined to occur.
4. The method of claim 1 , wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises:
determining whether a slope of a cardiac output signal is increasing over the period of time; and
determining long-term improvement on one or more of dilation of chambers and muscular endurance of the patient's heart in response to determining that the slope of the cardiac output signal is increasing over the period of time.
5. The method of claim 1 , wherein monitoring the one or more parameters comprises sensing a cardiac impedance signal during delivery of the cardiac remodeling pacing,
wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises determining whether there is a predetermined change in impedance indicative of dilation of heart chambers based on the sensed cardiac impedance signal over the period of time,
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises adjusting delivery of the cardiac remodeling pacing in response to determining that the predetermined change in impedance occurred.
6. The method of claim 1 , wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises determining changes in pulmonary pressure during delivery of the cardiac remodeling pacing over the period of time,
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises adjusting delivery of the cardiac remodeling pacing in response to the determining changes in pulmonary pressure during delivery of the cardiac remodeling pacing over the period of time.
7. The method of claim 1 , wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises adjusting a duty cycle of the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart.
8. The method of claim 1 , wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises:
determining a recovery rate associated with an amount of time for a heart rate to return to a resting heart rate after delivery of the cardiac remodeling pacing during each session over the plurality of sessions over the period of time; and
comparing the determined recovery rate for each session to a baseline recovery rate,
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises determining whether to suspend delivery of the cardiac remodeling pacing in response to the comparing the determined recovery rate of each session to the baseline recovery rate.
9. The method of claim 1 , wherein monitoring the one or more parameters comprises sensing a cardiac signal during delivery of the cardiac remodeling pacing, wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises determining whether there is a predetermined change in a systolic time interval based on the sensed cardiac signal over the period of time,
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises determining whether to suspend delivery of the cardiac remodeling pacing in response to determining that the predetermined change in the systolic time interval occurred.
10. The method of claim 1 , wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises:
determining a long-term change in a biomarker indicator indicative of heart failure during the delivery of the cardiac remodeling pacing over the period of time; and
determining whether the long-term change in the biomarker indicator is indicative of there being a long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart,
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises suspending delivery of the cardiac remodeling pacing in response to determining that the long-term change in the biomarker indicator is indicative of the long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart.
11. The method of claim 10 , wherein the biomarker indicator comprises a brain natriuretic peptide.
12. The method of claim 1 , wherein monitoring the one or more parameters comprises monitoring a systolic time interval (STI) over the period of time,
wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises:
generating a long-term STI based on the monitored STI over the plurality of sessions; and
comparing the long-term STI to a baseline STI,
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises determining whether to suspend delivery of the cardiac remodeling pacing in response to the comparing the long-term STI to the baseline STI.
13. A cardiac device for delivering a cardiac remodeling pacing to a patient, comprising:
a housing;
a plurality of electrodes electrically connected to the housing to deliver cardiac remodeling pacing to stimulate one or more of dilation of chambers and muscular endurance of the patient's heart; and
a processor positioned within the housing and configured to:
initiate delivery of cardiac remodeling pacing when the patient is inactive using the plurality of electrodes to deliver electrical pulses to the patient's heart to increase the patient's heart rate to stimulate one or more of dilation of chambers and muscular endurance of the patient's heart during a plurality of sessions over a period of time, wherein the period of time is greater than or equal to one week, wherein the cardiac remodeling pacing is suspended between each of the plurality of sessions,
monitor one or more parameters, wherein at least one of the one or more parameters is indicative of an effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart over the period of time,
determine a long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time, wherein the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart is indicative of the effect of the delivered cardiac remodeling pacing on cardiac normalization over the period of time,
adjust the cardiac remodeling pacing during a present session of the plurality of sessions in response to the one or more parameters monitored during the present session of the plurality of sessions, and
adjust the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart.
14. The device of claim 13 , wherein monitoring the one or more parameters comprises sensing a cardiac signal during delivery of the cardiac remodeling pacing,
wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises:
determining QRS durations over the period of time based on the sensed cardiac signal, and
determining whether the QRS durations are increasing over the period of time,
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises adjusting the cardiac remodeling pacing in response to determining that the QRS durations are increasing over the period of time.
15. The device of claim 13 , wherein the processor is configured to:
divide each session of the plurality of sessions during which the cardiac remodeling pacing is delivered into predetermined time segments,
wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises determining, for each of the predetermined time segments, whether AV-block is occurring,
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises inhibiting the cardiac remodeling pacing delivery during the predetermined time segments for which AV-block was determined to occur.
16. The device of claim 13 , wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises:
determining whether a slope of a cardiac output signal is increasing over the period of time; and
determining long-term improvement on one or more of dilation of chambers and muscular endurance of the patient's heart in response to determining that the slope of the cardiac output signal is increasing over the period of time.
17. The device of claim 13 , wherein monitoring the one or more parameters comprises sensing a cardiac impedance signal during delivery of the cardiac remodeling pacing,
wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises determining whether there is a predetermined change in impedance indicative of dilation of heart chambers based on the sensed cardiac impedance signal over the period of time,
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises adjusting delivery of the cardiac remodeling pacing in response to determining that the predetermined change in impedance occurred.
18. The device of claim 13 , wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises determining changes in pulmonary pressure during delivery of the cardiac remodeling pacing over the period of time,
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises adjusting delivery of the cardiac remodeling pacing in response to the determining changes in pulmonary pressure during delivery of the cardiac remodeling pacing over the period of time.
19. The device of claim 13 , wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises adjusting a duty cycle of the cardiac remodeling pacing in response to the determined the effect on one or more of dilation of chambers and muscular endurance of the patient's heart.
20. The device of claim 13 , wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises:
determining a recovery rate associated with an amount of time for a heart rate to return to a resting heart rate after delivery of the cardiac remodeling pacing during each session over the plurality of sessions over the period of time; and
comparing the determined recovery rate for each session to a baseline recovery rate,
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises determining whether to suspend delivery of the cardiac remodeling pacing in response to the comparing the determined recovery rate for each session to the baseline recovery rate.
21. The device of claim 13 , wherein monitoring the one or more parameters comprises sensing a cardiac signal during delivery of the cardiac remodeling pacing, wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises determining whether there is a predetermined change in a systolic time interval based on the sensed cardiac signal over the period of time,
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises determining whether to suspend delivery of the cardiac remodeling pacing in response to determining that the predetermined change in the systolic time interval occurred.
22. The device of claim 13 , wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises:
determining a long-term change in a biomarker indicator indicative of heart failure during the delivery of the cardiac remodeling pacing over the period of time; and
determining whether the long-term change in the biomarker indicator is indicative of a long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart,
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises suspending delivery of the cardiac remodeling pacing in response to determining that the long-term change in the biomarker indicator is indicative of the long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart.
23. The device of claim 22 , wherein the biomarker indicator comprises a brain natriuretic peptide.
24. The device of claim 13 , wherein monitoring the one or more parameters comprises monitoring a systolic time interval (STI) over the period of time,
wherein determining the long-term effect of the delivered cardiac remodeling pacing on one or more of dilation of chambers and muscular endurance of the patient's heart based on the one or more parameters monitored over the period of time comprises:
generating a long-term STI based on the monitored STI over the plurality of sessions; and
comparing the long-term STI to a baseline STI,
wherein adjusting the cardiac remodeling pacing in response to the determined long-term effect on one or more of dilation of chambers and muscular endurance of the patient's heart comprises determining whether to suspend delivery of the cardiac remodeling pacing in response to the comparing the long-term STI to the baseline STI.