METHODS AND APPARATUS TO STIMULATE HEART ATRIA

• US 20100094370A1
• Filed: 09/08/2009
• Published: 04/15/2010
• Est. Priority Date: 09/08/2008
• Status: Active Grant

• Current Assignee: Backbeat Medical, LLC
• Original Assignee: G & L Consulting LLC.
• Inventors: Gelfand, Mark, Levin, Howard
• Granted Patent: US 8,340,763 B2
• Time in Patent Office: Days
• US Class Current: 607/19
• CPC Class Codes: A61N 1/36117 for treating hypertension
• CPC Class Codes: A61N 1/3621 for treating or preventing abnormally high heart rate
• CPC Class Codes: A61N 1/3627 for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy
• CPC Class Codes: A61N 1/36542 controlled by body motion, e.g. acceleration
• CPC Class Codes: A61N 1/36564 controlled by blood pressure
• CPC Class Codes: A61N 1/368 comprising more than one electrode co-operating with different heart regions A61N1/3622, A61N1/3627 take precedence
• CPC Class Codes: A61N 1/3684 for stimulating the heart at multiple sites of the ventricle or the atrium

Abstract

A method and apparatus for treatment of hypertension and heart failure by increasing secretion of endogenous atrial hormones by pacing of the heart atria. Atrial pacing is done during the ventricular refractory period resulting in premature atrial contraction that does not result in ventricular contraction. Pacing results in the atrial wall stress, peripheral vasodilation, ANP secretion. Concomitant reduction of the heart rate is monitored and controlled as needed with backup pacing.

Claims

1. A method of controllably reducing blood pressure in a human having an cardiac pacemaker pacing an atrium of a heart comprising:

sensing a ventricular refractory period of the heart;

pacing the atrium of with the cardiac pacemaker during the ventricular refractory period, with a first pacing pulse, where said first atrial pacing pulse is blocked and does not propagate to the ventricle of the heart and said first atrial pacing pulse causes an atrial contraction against a closed A-V valve and induced increased atrial wall stress resulting in ANP release by the stressed atrial wall;

monitoring a heart rate after the atrium is paced, and

applying a second pacing pulse to the atrium of the heart if the heart rate is less than a threshold minimum heart rate.

2. A method has to reduce blood pressure in a human having a cardiac pacemaker pacing an atrium of a heart comprising:

sensing a first ventricular contraction of the heart;

applying a first atrial pacing pulse to the atrium with the cardiac pacemaker, wherein the first atrial pacing pulse is applied upon expiration of a predetermined delay following the atrial refractory period and during the first ventricular refractory period;

monitoring the heart beat of the patient in conjunction with applying the first atrial pacing pulse;

applying second atrial pacing pulse to the atrium if the monitored heart beat is less than a predetermined minimum heart rate.

3. The method recited in claim 2 further comprising reducing the predetermined delay when the first atrial pacing pulse is detected to propagate to the ventricle.

4. The method in claim 2 further comprising periodically increasing the predetermined delay to coincide with an expiration of the ventricular refractory period.

5. The method in claim 2 further comprising setting a the time of said second atrial pacing to a time less than a refractory period.

6. The method recited in claim 2 further comprising suspending the application of the first atrial pacing pulse and the second atrial pacing pulse when an exercise activity of the patient is determined to be above a predetermined threshold level.

7. The method of claim 6 wherein the exercise activity as detected by the pacemaker.

8. The method in claim 2 further comprising applying the first atrial pacing pulse in response to a sensed ventricular depolarization of the heart.

9. The method in claim 2 further comprising sensing a ventricular depolarization of the heart and applying the first atrial pacing pulse upon expiration of a predetermined delay from the sensed ventricular depolarization.

10. The method in claim 2 further comprising applying the first atrial pacing pulse based on a sensed atrial depolarization of the heart.

11. A method of artificially inducing atrial wall stress in a heart of a patient comprising:

detecting ventricular depolarization of the heart;

applying atrial pacing pulses to induce atrial contraction, where said pacing is applied while ventricular pressure is higher than atrial pressure and while the AV conduction is refractory;

blocking the first atrial pacing pulses from propagating to the ventricle;

monitoring a heart beat of the patient while applying the atrial pacing pulses;

applying backup pacing pulses to the atrium or ventricle when the heart beat is less than predetermined minimum rate;

wherein the atrial pacing pulses and the backup pacing pulses induce peripheral vascular vasodilation which causes a change in a blood pressure in the patient.

12. A method of controllably reducing heart by pacing a heart of a patient having an atria and a ventricle comprising:

sensing a first ventricular contraction of the heart;

pacing a atrium of the heart, where the said atrial pacing occurs at an expiration of a atrial refractory period of the heart and during a ventricular refractory period of the heart;

causing an atrial contraction from the pacing, wherein the atrial contraction does not propagate to a second ventricular contraction, and

said atrial contraction causes a vasodilation and ANP release in the heart.

13. The method of claim 12 further comprising monitoring a the ventricular contraction rate resulting from the pacing, and adjusting a period of the said atrial pacing based on the ventricular contraction rate.

14. The method of claim 12 wherein the pacing pulses are applied upon expiration of a predetermined delay after the said sensed first ventricular contraction.

15. The method of claim 14 wherein the predetermined delay is adjusted based on a detected propagation of the pacing to the ventricle.

16. The method of claim 14 further comprising monitoring a spontaneous heart beat after application of said pacing pulses, and delivering another atrial pacing pulse if the predetermined delay is longer than a predetermined period corresponding to a lowest selected heart rate, wherein said another atrial pacing generates ventricular contraction.