Methods and systems for detecting and treating heart instability

• US 9,393,425 B2
• Filed: 12/19/2013
• Issued: 07/19/2016
• Est. Priority Date: 05/13/2008
• Status: Expired due to Fees

• Current Assignee: United States Department of Veterans Affairs Office of General Counsel, Regents of the University of California (University of California)
• Original Assignee: The United States of America As Represented By The Secretary of Agriculture, Regents of the University of California (University of California)
• Inventors: Narayan, Sanjiv
• Primary Examiner(s): Stigell, Theodore
• Assistant Examiner(s): Patel, Natasha
• Application Number:
  US14/135,472
• Publication Number:
  US 20140194763A1
• Time in Patent Office: 943 Days
• US Class Current: 1/1
• CPC Class Codes: A61B 18/14 Probes or electrodes therefor
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 5/0036 including treatment, e.g., using an implantable medical device, ablating, ventilating
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/0245 by using sensing means generating electric signals, i.e. ECG signals
• CPC Class Codes: A61B 5/29 for permanent or long-term implantation
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/361 Detecting fibrillation
• CPC Class Codes: A61B 5/363 Detecting tachycardia or bradycardia
• CPC Class Codes: A61B 5/366 Detecting abnormal QRS complex, e.g. widening
• CPC Class Codes: A61B 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor
• CPC Class Codes: A61N 1/36114 Cardiac control, e.g. by vagal stimulation stimulating the heart A61N1/362
• CPC Class Codes: A61N 1/3621 for treating or preventing abnormally high heart rate
• CPC Class Codes: A61N 1/36592 controlled by the heart rate variability
• CPC Class Codes: G16H 50/30 for calculating health indices; for individual health risk assessment
• CPC Class Codes: G16Z 99/00 Subject matter not provided for in other main groups of this subclass

Abstract

Systems and methods define an index of risk for cardiac disease by detecting cellular derangements that may lead to cardiomyopathy, heart rhythm disorders or ischemic heart disease. The markers include fluctuations or abnormal rate-behavior of electrical, mechanical or other measurable biosignals. The invention operates in modes that can be applied to prevent atrial fibrillation or the risk for ventricular arrhythmias. Alternative embodiments are applied to tissue outside the heart such as skeletal muscle, smooth muscle, the central nervous system, the respiratory system, the urogenital system and the gastrointestinal system.

Claims

1. An apparatus associated with diagnosis and treatment of a suspected heart rhythm disorder in a beating human heart, the apparatus comprising:

one or more sensors configured to detect one or more signals from the beating human heart over a plurality of time segments;

a diagnostic unit configured to calculate one or a combination of signal changes in response to a variation in at least one of rate and regularity induced in the beating human heart, the variation being induced to determine whether the signal changes indicate the suspected heart rhythm disorder, the signal changes being in at least one of signal shape, duration of signal components, signal amplitude and signal characteristics among a first time segment and a second time segment of the plurality of time segments, wherein at least a portion of the second time segment differs from at least a portion of the first time segment; and

a therapy unit configured to modify at least one of tissue structure and function based at least in part on the signal changes determined by the diagnostic unit.

2. The apparatus of claim 1, wherein the signals represent action potentials.

3. The apparatus of claim 2, wherein the signal changes in the signal characteristics comprise a change in a slope of a rate-response associated with the signal changes calculated in response to the variation in at least one of rate and regularity induced in the beating human heart.

4. The apparatus of claim 2, further comprising a detection unit to detect conduction slowing.

5. The apparatus of claim 4, wherein the conduction slowing affects at least one of the signal changes calculated in response to the variation in at least one of rate and regularity induced in the beating human heart.

6. An apparatus to assess a risk associated with a suspected heart rhythm disorder comprising:

at least one sensor; and

an analytic engine comprising;

a module configured to measure a signal received via the at least one sensor from a beating human heart;

a module configured to calculate a change in the signal among at least a first time segment and a second time segment, the change in the signal being in response to a variation in at least one of rate and regularity induced in the beating human heart, the variation being induced to determine whether the change in the signal indicates the suspected heart rhythm disorder, wherein at least a portion of the second time segment differs from at least a portion of the first time segment; and

a module configured to generate a risk score for the suspected heart rhythm disorder determined based at least in part on the change in the signal.

7. The apparatus of claim 6, further comprising a module configured to construct a rate-response curve and measure a slope of the rate-response curve.

8. The apparatus of claim 7, wherein fluctuations in the rate-response curve are affected by signal changes in at least one of shape of the signal, duration of components of the signal, amplitude of the signal and signal characteristics in response to the variation in at least one of rate and regularity induced in the beating human heart.

9. The apparatus of claim 6, further comprising a module configured to control excitation of tissue of the beating human heart.

10. The apparatus of claim 9, wherein excitation of tissue comprises pacing the tissue to change the rate associated with the signal.

11. The apparatus of claim 6, wherein the change in the signal is calculated between alternate beats of the beating human heart.

12. The apparatus of claim 9, wherein excitation of tissue comprises pacing the tissue out-of-phase with changes calculated in the signal at different rates.

13. The apparatus of claim 6, further comprising a module configured to control modification of tissue of the beating human heart.

14. The apparatus of claim 13, wherein modification of tissue comprises ablation of the tissue.

15. The apparatus of claim 6, further comprising:

an energy generator coupled to an ablation electrode;

an electrode controller coupled to the at least one sensor;

a process controller coupled to the electrode controller and the energy generator;

a sampling module configured to record the signal; and

a pacing module configured to send a pacing signal to a pacing electrode, wherein the signal excites tissue.

16. An apparatus associated with treatment of a suspected heart rhythm disorder in a beating human heart, the apparatus comprising:

one or more sensors configured to detect one or more signals from the beating human heart over a plurality of time periods;

a diagnostic unit configured to calculate one or a combination of signal changes in response to a variation in at least one of rate and regularity induced in the beating human heart, the variation being induced to determine whether the signal changes the suspected heart rhythm disorder, the signal changes being in at least one of signal shape, duration of signal components, signal amplitude and signal characteristics among a first time period and a second time period of the plurality of time periods, wherein at least a portion of the first time period differs from at least a portion of the second time period; and

an assignment unit configured to assign a risk score for the suspected heart rhythm disorder based at least in part on the signal changes calculated by the diagnostic unit.

17. The apparatus of claim 16, wherein the signals represent action potentials.

18. The apparatus of claim 16, wherein the signal changes in the signal characteristics comprise a change in a slope of a rate-response associated with the signal changes calculated in response to the variation in at least one of rate and regularity induced in the beating human heart.

19. The apparatus of claim 16, further comprising a detection unit to detect conduction slowing.

20. The apparatus of claim 19, wherein the conduction slowing affects at least one of the signal changes calculated in response to the variation in at least one of rate and regularity induced in the beating human heart.

21. The apparatus of claim 16, further comprising a modification unit configured to modify at least one of tissue structure and function of the beating human heart based at least in part on the signal changes calculated in response to the variation in at least one of rate and regularity induced in the beating human heart.