US-12616827-B2 - System and method for assisting the heart in pumping blood

Abstract

A system and method of increasing the pumping efficiency of an individual's heart, wherein an actual pumping efficiency is compared to an optimal pumping efficiency to determine a force assist profile. A cardiac assist device is created that will apply the force assist profile to the heart. The cardiac assist device is surgically inserted in vivo to physically affect the heart. The cardiac assist device has an outer shell and at least one inflatable membrane that passes over the ventricles of the heart, wherein the inflatable membrane is inflated and deflated in accordance with a pressure profile provided by a pneumatic pump. The outer shell embodies outer shell strain characteristics. Each inflatable membrane embodies membrane strain characteristics. The force assist profile is a function of the outer shell strain characteristics, the membrane strain characteristics, and the pressure profile.

Inventors

• Mark P. Anstadt

Assignees

• LIFEBRIDGE TECHNOLOGIES, LLC

Dates

Publication Date

20260505

Application Date

20231114

Claims (8)

1. 1 . A cardiac assist device, comprising: a base having a rim and a base apex, wherein said base has a base height between said rim and said base apex; an outer shell having an open top, wherein said open top is positioned atop said rim of said base therein forming a cup assembly for receiving a portion of a heart therein, said cup assembly having an overall height from said base apex to said open top, wherein said base height is between twenty-five percent and thirty-five percent of said overall height, wherein said outer shell is made, at least in part, from elastomeric material that enables said outer shell to be able to elastically expand, contract, elongate, shorten and/or twist, wherein said outer shell has an inner surface; and at least one inflatable membrane lining only said inner surface of said outer shell, wherein said at least one inflatable membrane is connected to said inner surface of said outer shell along a basal bond that is a first distance from said open top and along an apical bond that is a further second distance from said open top, wherein said at least one inflatable membrane contacts the heart within the cup assembly as said at least one inflatable membrane is selectively inflated and both said outer shell and said at least one inflatable membrane combine to provide a force assist profile that causes the heart to pump more efficiently when applied to the heart using the cardiac assist device.
2. 2 . The cardiac assist device according to claim 1 , wherein said at least one inflatable membrane creates elastic displacements in said outer shell when said at least one inflatable membrane is selectively inflated, wherein said elastic displacements in said outer shell generate forces that contribute to said force assist profile.
3. 3 . The cardiac assist device according to claim 1 , wherein said at least one inflatable membrane is inflated and deflated in accordance with a pressure profile, wherein said pressure profile along with both said outer shell and said at least one inflatable membrane combine to provide said force assist profile.
4. 4 . The cardiac assist device according to claim 1 , wherein said at least one inflatable membrane is selectively inflated and deflated in accordance with a pressure profile provided by a pneumatic pump.
5. 5 . The cardiac assist device according to claim 4 , wherein said outer shell embodies outer shell strain characteristics that are a function of dimensions and materials embodied by said outer shell.
6. 6 . The cardiac assist device according to claim 5 , wherein said at least one inflatable membrane embodies membrane strain characteristics that are a function of dimensions and materials embodied by said at least one inflatable membrane.
7. 7 . The cardiac assist device according to claim 6 , wherein said force assist profile is a function of said outer shell strain characteristics, said membrane strain characteristics, and said pressure profile.
8. 8 . The cardiac assist device according to claim 1 , wherein said first distance of said basal bond is a distance below the open top that is no greater than five percent of said overall height.

Description

RELATED APPLICATIONS This application is a continuation-in-part of co-pending U.S. application Ser. No. 17/825,343 filed May 26, 2022, which is a continuation-in-part of U.S. application Ser. No. 17/208,776 filed Mar. 22, 2022, now U.S. Pat. No. 11,383,076, which claimed priority of U.S. Provisional Application No. 63/086,478 filed Oct. 1, 2020. This application is also a continuation-in-part of U.S. application Ser. No. 18/150,746 filed Jan. 5, 2023, which is a continuation-in-part of U.S. application Ser. No. 17/931,853 filed Sep. 13, 2022, now U.S. Pat. No. 12,263,332. This application is a further continuation-in-part of U.S. patent application Ser. No. 18/160,963, filed Jan. 27, 2023, now U.S. Pat. No. 11,869,812. This application is yet a further continuation-in-part of U.S. application Ser. No. 18/447,786 filed Aug. 10, 2023, now U.S. Pat. No. 12,115,363. BACKGROUND OF THE INVENTION 1. Field of the Invention In general, the present invention relates to cardiac assist systems and methods that help the heart pump blood by applying forces to the exterior of the heart. More particularly, the present invention relates to the structure of the cardiac assist systems and their methods of operation. 2. Prior Art Description There are many instances when a heart needs assistance to maintain a proper blood flow in a patient. Often hearts that are diseased, failing, or have stopped need the application of a cardiac assist system to prevent a patient from dying. Furthermore, the proper mechanical massaging of the failing heart may have additional therapeutic implications for recovery. In the prior art, many cardiac assist systems pierce the heart and/or vascular system so as to have direct effect upon the patient's blood. However, thromboembolic events, the need for anticoagulation, hemolysis, immune reactions, and infections, contribute significantly to morbidity and mortality of such cardiac assist systems. Accordingly, it is preferable that the pumping of the heart be assisted not by directly acting upon the blood but by applying forces to the external surfaces of the heart as the heart expands and contracts. In this manner, the heart pumps the blood without having to interrupt the natural flow of the blood. Furthermore, the proper force applications to the external surfaces of the heart may aid in the heart's recovery. In the prior art, there are many constructs that surround the ventricles of the heart and apply forces to the ventricles. Such systems are typically designed to help the ventricles of the heart to empty. However, the heart is a complex organ that both empties and fills as it pumps. In order for a heart to pump blood effectively and efficiently, a heart often needs assistance in both filling and emptying. Additionally, proper mechanical forces applied to the heart which still has some pumping function can aid in the heart's diastolic and systolic function and facilitate more physiologic heart function during filling and emptying cycles of a heart. In U.S. Pat. No. 3,455,298, Dr. George Anstadt introduced a cardiac assist device that assists a heart in both its systolic and diastolic cycles. The device, known in the medical industry as the Anstadt cup, is a cup-shaped construct that fits over the ventricles of the heart. The Anstadt cup has a stiff outer shell and an inflatable inner membrane. The outer shell and inflatable membrane are placed around the ventricles of the heart. When the inflatable membrane expands, the inflatable membrane compresses the heart, therein helping with the heart's emptying or its systolic function when native heart function is still present. When the membrane deflates, there is a negative pressure that is created between the tissue of the heart and the stiff outer shell. This negative pressure assists the heart in filling, or with its diastolic pump function, when native heart function is still present. Although the Anstadt cup does assist in the heart's pump function, the assist is less than optimal. Likewise, since the inflatable membrane is positioned between a rigid shell and the heart, the forces that can be applied to the heart are not nuanced. When the heart has an inherent pump function, the heart does more than fill and empty. During the pumping cycle, the heart also elongates and contracts. Likewise, ventricular tissue also twists as it expands and contracts. A cardiac assist device that uses a rigid shell and non-ideal membrane characteristics has very limited ability to follow the heart surface as the heart elongates, contracts and/or twists. This is important to conditions where the heart has no pump function and is changing its conformation in response to the device's forces, as well as when the heart is exhibiting inherent pump function and the device is aiding in promoting physiologic diastolic and systolic pump function. As a result, some areas of the heart experience higher surface forces than they should be, and some areas experience less surface f