[Diagnostic value of tissue Doppler parameters in the early diagnosis of cardiomyopathies].

Tissue Doppler and its derived parameters strain and strain rate show characteristic changes in patients with cardiomyopathy. Longitudinal systolic (S) and early diastolic (E') peak tissue velocities are reduced in the basal segments of the left ventricle in patients with dilated, hypertrophic, and restrictive cardiomyopathies, and in the right ventricular free wall in patients with arrhythmogenic dysplasia of the right ventricle. Similarly, strain and strain rate are lower than in normals. These changes are detectable in asymptomatic, genetically affected patients and in early stages of cardiomyopathy, where conventional echo signs such as impaired left ventricular ejection fraction or increased wall thickness are not yet present. Thus, tissue Doppler analysis may contribute to better identifying carriers of disease and subclinical early stages of cardiomyopathy. However, lack of measurement standardization and small numbers of cardiomyopathy patients examined by Doppler, together with difficulty in defining reliable normalcy ranges, still hamper widespread clinical use of this new tool.