Left Ventricular Mechanics in Idiopathic Dilated Cardiomyopathy: Systolic-Diastolic Coupling and Torsion

Background: In idiopathic dilated cardiomyopathy (IDC), myocardial deformational parameters and their mutual relationships remain incompletely characterized. Methods: Thirty-seven patients with IDC underwent two-dimensional speckle-tracking echocardiography (2D-STE) to assess left ventricular rotation, torsion, and longitudinal, circumferential, and radial systolic and diastolic strains and strain rates. Additionally, 2D-STE was performed in 14 controls. Results: All deformational parameters on 2D-STE were significantly lower in patients with IDC compared with controls. Seven patients exhibited opposite basal (positive, counterclockwise) and 11 patients exhibited opposite apical (negative, clockwise) rotation at end-systole. Circumferential, radial, and longitudinal early diastolic strain rates were correlated most strongly with the corresponding spatial components of systolic deformation. Conclusion: In patients IDC, all torsional, systolic, and diastolic deformational parameters were decreased. Corresponding three-dimensional components of systolic and diastolic deformations were closely coupled. Considerable variation in the direction of basal and apical rotation exists in a subset of patients with IDC. (J Am Soc Echocardiogr 2009; 22: 486-493.)