Some studies consider that coronary microcirculationcan be directly affected by cardiomyopathy[18]. Thus, according to some authors [19], in end stagedilated cardiomyopathy myocardial blood flow isseverely reduced. Studies using positron emissiontomography showed that 82% of patients with dilatedcardiomyopathy have reduced myocardial flow due to adysfunction of coronary microcirculation [20]. Webelieve that it is currently difficult to determine whethercoronary microcirculation impairment causes dilatedcardiomyopathy phenomena, or they are secondary tothe evolution of dilated cardiomyopathy