Edema diffuses more than myocardial ischemia and decreases within a few weeks unlike myocardial ischemia, which may take up to 3 months to diminish [115]. Typically, there is no LGE. However, recent studies have shown that LGE may be present in up to 40% of patients, typically in the areas of RWMA. This is usually of lower signal intensity (<5 SD above remote normal myocardium) than the LGE of myocardial infarction [87]. These patients may have irreversible damage with worse prognosis and longer recovery time [116,117]. MR diagnosis of stress-induced cardiomyopathy is made based on a typical pattern of LV dysfunction in a noncoronary pattern, myocardial edema corresponding to areas with RWMA, absence or insignificant LGE (<5 SD above remote normal myocardium), and markers for myocardial inflammation (EGE ratio > 4.0) [114]. MRI is superior to echocardiography in evaluating the RV involvement and complications [114]. Functional improvement occurs usually in 3 to 4 months but may take up to 12 months in 5% of patients; it may recur in 5% to 11% of patients [87]. Although stress-induced cardiomyopathy was typically thought to be completely reversible, recent literature indicates long-term clinical consequences [118]. MRI Heart Inotropic Stress There is no relevant literature to support the use of MRI heart inotropic stress for the evaluation of nonischemic DCM or unclassified cardiomyopathy when ischemia has already been excluded. MRI Heart Vasodilator Stress There is no relevant literature to support the use of MRI vasodilator stress for the evaluation of nonischemic DCM or unclassified cardiomyopathy when ischemia has already been excluded. Echocardiography Transesophageal There is no relevant literature to support the use of transesophageal echocardiography for the evaluation of nonischemic DCM or unclassified cardiomyopathy.
Nonischemic Myocardial Disease with Clinical Manifestations Ischemic Cardiomyopathy Already Excluded . Edema diffuses more than myocardial ischemia and decreases within a few weeks unlike myocardial ischemia, which may take up to 3 months to diminish [115]. Typically, there is no LGE. However, recent studies have shown that LGE may be present in up to 40% of patients, typically in the areas of RWMA. This is usually of lower signal intensity (<5 SD above remote normal myocardium) than the LGE of myocardial infarction [87]. These patients may have irreversible damage with worse prognosis and longer recovery time [116,117]. MR diagnosis of stress-induced cardiomyopathy is made based on a typical pattern of LV dysfunction in a noncoronary pattern, myocardial edema corresponding to areas with RWMA, absence or insignificant LGE (<5 SD above remote normal myocardium), and markers for myocardial inflammation (EGE ratio > 4.0) [114]. MRI is superior to echocardiography in evaluating the RV involvement and complications [114]. Functional improvement occurs usually in 3 to 4 months but may take up to 12 months in 5% of patients; it may recur in 5% to 11% of patients [87]. Although stress-induced cardiomyopathy was typically thought to be completely reversible, recent literature indicates long-term clinical consequences [118]. MRI Heart Inotropic Stress There is no relevant literature to support the use of MRI heart inotropic stress for the evaluation of nonischemic DCM or unclassified cardiomyopathy when ischemia has already been excluded. MRI Heart Vasodilator Stress There is no relevant literature to support the use of MRI vasodilator stress for the evaluation of nonischemic DCM or unclassified cardiomyopathy when ischemia has already been excluded. Echocardiography Transesophageal There is no relevant literature to support the use of transesophageal echocardiography for the evaluation of nonischemic DCM or unclassified cardiomyopathy.