Artificial Myocardium: Design Principles and Substratum

Abstract

Death and disability due to cardiovascular disease and congenital anomalies remains a significant health problem in the United States. Despite improvements in detection, patient management, surgery and preventative medicine, the quality of life for people who suffer from cardiovascular dysfunction has a major impact on our society. The intact heart is an elaborate three-dimensional structure that insures the orderly propagation of electrical signals coordinating the contraction and relaxation of the ventricular wall. Localized loss of muscular tissue as a result of congenital defect or disease process alters this structural arrangement and impairs overall cardiac function. Conventional surgical techniques cannot begin to adequately restore the subtle structural and functional relationships in the heart. The ability to construct a tissue-engineered prosthesis composed of cardiac muscle cells in a collagen-based scaffold may potentially offer a superior alternative to currently available surgical techniques.

A tissue engineered myocardium must have the following components: First, it must develop and maintain the correct cellular phenotype as well as a functioning contractile apparatus of parallel myofibrils, Second it must be able to form gap junctions within itself and with the native tissue and these gap junctions must be competent at conducting electrical pacing as well as other biochemical signals, and Third, it must be capable of participating in and contributing to the rhythmic contraction of normal myocardium as well as accommodate the changes in contraction frequency ubiquitous in the cardiac environment