[Myocardiopathies (III). The classification and morphological patterns of hypertrophic myocardiopathy].

Hypertrophic cardiomyopathy is characterized by a great variety of clinical manifestations and morphologic patterns. Hemodynamic classification in obstructive and nonobstructive forms may be clinically relevant since, although many patients have disabling symptoms in the absence of a pressure gradient, in the subset of patients who do have a gradient, symptom severity seems to relate its magnitude; this fact supports the use of some therapeutic approaches directed to reduce or eliminate obstruction. Nevertheless, the presence and severity of the gradient do not correlate with prognosis. On the other hand, from a morphological point of view, any classification will be limited by the great diversity of morphologic patterns, which include almost all forms of ventricular hypertrophy one could imagine, and by the possibility of significant changes in the severity and distribution of the hypertrophy during the life of the patient. In general, the degree and distribution of ventricular hypertrophy do not correlate with symptoms or prognosis. The identification of different molecular genetic abnormalities responsible for the development of hypertrophic cardiomyopathy, is expected to provide new insights in the etiology and pathogenesis of this disease, which should be considered in future classifications.