Method and apparatus to optimize pacing heart rate
The present disclosure provides an apparatus and method of optimizing a pacing heart rate. The method can include obtaining a preload-frequency relation and a force-frequency relation from histogram data for a patient condition and determining an optimal pacing heart rate for the patient condition. The optimal pacing heart rate can be substantially between a first heart rate corresponding to a minimum preload condition based on the preload-frequency relation and a second heart rate corresponding to a sustained ionotropic reserve condition based on the force-frequency relation.
1. A pacing implantable medical device comprising:
a data collection module configured to obtain a pressure signal and a heart rate signal;
a data processing module coupled to the data collection module,
the data processing module configured to generate a preload-frequency relation and a force-frequency relation from histogram data for a patient condition,
the data processing module configured to determine an optimal pacing heart rate for the patient condition, the optimal pacing heart rate being substantially between a first heart rate corresponding to a minimum preload condition based on the preload-frequency relation and a second heart rate corresponding to a sustained ionotropic reserve condition based on the force-frequency relation; and
a therapy module coupled to the data processing module, the therapy module configured to provide the optimal pacing heart rate.
2. The device of claim 1 wherein the pressure signal is a right ventricle diastolic pressure signal.
3. The device of claim 1 wherein the therapy module provides cardiac resynchronization therapy.
4. The device of claim 1 wherein the preload-frequency relation is a first curve of right ventricular diastolic pressure versus heart rate; and wherein the force-frequency relation is a second curve of a first derivative of right ventricular diastolic pressure versus heart rate.
5. The device of claim 4 wherein the minimum preload condition is a minimum heart rate on the first curve.
6. The device of claim 4 wherein the sustained ionotropic reserve condition is an upstroke in the second curve.
7. The device of claim 2 wherein the data collection module collects the right ventricular diastolic pressure signal for an extended time period before generating the histogram data for the patient condition.
8. The device of claim 1 and further comprising generating a plurality of histograms for each one of a plurality of patient conditions.
9. The device of claim 8 wherein the plurality of patient conditions includes at least two of resting, exercise, fluid-overload, day-time, and night-time.
10. The device of claim 1 and further comprising obtaining accelerometer data and generating a plurality of histograms representing each one of a plurality of patient conditions including different activity levels based on the accelerometer data.
11. The device of claim 1 wherein the patient condition is a resting fluid-overload condition; and wherein the optimal pacing heart rate is a heart rate representing an upstroke in the second curve.