External stress reduction device and method

Abstract

An external heart wall stress reduction apparatus is provided to create a heart wall shape change. The device is generally disposed to the exterior of a heart chamber to reshape the chamber into a lower stress configuration.

Description

FIELD OF THE INVENTION [0001] The present invention pertains to the field of heart failure in devices and methods for treatment thereof. BACKGROUND OF THE INVENTION [0002] The syndrome of heart failure is a common course for the progression of many forms of heart disease. Heart failure may be considered to be the condition in which an abnormality of cardiac function is responsible for the inability of the heart to pump blood at a rate commensurate with the requirements of the metabolizing tissues, or can do so only at an abnormally elevated filling pressure. There are many specific disease processes that can lead to heart failure with a resulting difference in pathophysiology of the failing heart, such as the dilatation of the left ventricular chamber. Etiologies that can lead to this form of failure include idiopathic cardiomyopathy, viral cardiomyopathy, and ischemic cardiomyopathy. [0003] The process of ventricular dilatation is generally the result of chronic volume overload or ...

AI Technical Summary

Benefits of technology

[0010] The devices and methods of the present invention are primarily external devices which need not necessarily penetrate the heart wall or transect a heart chamber. These devices can be used instead of, or in addition to, internal or transventricular devices. Unlike transventricular devices, however, avoidance of internal ventricular structures such as valves or chordae is not a concern. It is desirable to limit the size of the external devices to limit inflammatory response that may be created by implanting the device. Additionally, the weight of the device should be limited to reduced movement and forces which can induce inflammatory response or other negative physiologic responses as well. To limit the weight and size of the device, the devices can be constructed with materials with high strength to weight ratios and high stiffness to weight ratios. Size and weight interact to effect the stability of the device on the heart. The devices are preferably stabilized on the heart by tissue ingrowth, sutures, friction fit or the like.

[0011] The devices and methods of the present invention can reduce heart wall stress throughout the cardiac cycle including end diastole and end systole. Alternately they can be used to reduce wall stress during the portions of the cardiac cycle not including end systole. Those devices which operate throughout the cardiac cycle can be referred to as “full cycle” devices whereas those that do not operate to reduce wall stress during end stage systole can be referred to as “restrictive” devices.

Problems solved by technology

Additionally, the weight of the device should be limited to reduced movement and forces which can induce inflammatory response or other negative physiologic responses as well.

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