ABSTRACT
The heart functions as a muscular pump that generates flow and maintains the pressure of blood in the circulatory system. Its function is dependent upon the rapid and continuous energy supply to the myocardium and efficient oxidative phosphorylation in cardiomyocytes supported by adequate coronary flow. Coronary heart disease can severely reduce or completely stop blood perfusion to the myocardium, resulting in myocardial infarction. Coronary heart disease is the single leading cause of death in the USA and heart attacks result in more than 500,000 deaths each year.1 After an acute myocardial infarction, the healing process can be divided into four phases: (1) cardiomyocyte death; (2) acute inflammation; (3) tissue granulation; and (4) remodeling/repair.2,3 Since adult mammalian ventricular myocyteslack regenerative capability, injured myocardium consistently forms scar tissue after a heart attack. The scar is living tissue consisting of metabolically active myofibroblasts nourished by the neovasculature and innervated by postganglionic nerve fibers.3
