The term ischemic cardiomyopathy has been used to describe significantly impaired left ventricular function (left ventricular ejection fraction ≤35 to 40 percent) that results from coronary artery disease. Despite the common clinical use of the term ischemic cardiomyopathy, ventricular dysfunction caused by coronary disease is not a cardiomyopathy as defined by the 2006 American Heart Association and 2008 European Society of Cardiology statements. (See "Definition and classification of the cardiomyopathies".)
There are two main pathogenetic mechanisms, which are importantly distinguished by the possibility of corrective therapy:
●Irreversible loss of myocardium due to prior myocardial infarction with ventricular remodeling. Recovery of myocardial function in such patients cannot be achieved by coronary revascularization since the infarcted tissue is not viable.
●At least partially reversible loss of contractility due to reduced function of ischemic but still viable myocardium, which can be detected on imaging studies. Hibernating myocardium is typically used interchangeably with viable myocardium. However, by strict definition, the term hibernating myocardium refers to contractile dysfunction in viable myocardium that improves after revascularization or perhaps medical therapy . Stunned myocardium refers to transient postischemic dysfunction and can coexist with hibernating myocardium . (See "Clinical syndromes of stunned or hibernating myocardium".)
This topic will emphasize the definition, incidence, and therapy of reversible ischemic cardiomyopathy. Diagnostic issues related to hibernating viable myocardium are discussed in detail separately. (See "Evaluation of hibernating myocardium" and "Dobutamine stress echocardiography in the evaluation of hibernating myocardium" and "Assessment of myocardial viability by nuclear imaging in coronary heart disease".)