[Morphologic findings in dilated cardiomyopathy and their relation to hemodynamics and catecholamine concentrations in the plasma and myocardium].

In 72 patients with dilated cardiomyopathy the degree of morphological alterations were studied by transvenous endomyocardial biopsy. These findings were correlated to the clinical status, left ventricular ejection fraction, and to the catecholamine concentrations in plasma and myocardium. Muscle fiber diameter was negatively correlated to ejection fraction (r = -0.3, p = 0.02) and to the volume fraction of mitochondria (r = -0.32, p = 0.001). Between plasma norepinephrine concentration and ejection fraction a significant negative correlation was found (r = -0.37, p = 0.001). In contrast, myocardial norepinephrine concentration was positively correlated to ejection fraction (r = 0.25, p = 0.04). Between myocardial norepinephrine concentration and muscle fiber diameter a negative correlation was found (r = -0.46, p = 0.004). Patients with an EF of less than 30% and an EF of greater than 45% could be differentiated with an accuracy of 79%, when muscle fiber diameter, plasma norepinephrine concentration, and the density of capillary vessels were entered into a multi-variant analysis. In conclusion, dilated cardiomyopathy is associated with morphological alterations and alterations in plasma and myocardial catecholamine concentrations. Patients with highly reduced ventricular function could be best identified by the combined assessment of plasma catecholamine concentration, muscle fiber diameter, and density of capillary vessels.