Left ventricular hypertrophy: A cytometric study on 42 human hearts

Abstract

A histocytometric study of 42 left ventricles was carried out. The cases consisted of normal hearts as well as a number of hypertrophic hearts which were progressively heavier in weight. The results of this study were analyzed by computer. We found an increase in myocardial cell size correlated with an increase in the ventricular free wall weight, up to a critical weight of 250 g. Beyond that critical weight, cellular hyperplasia was evident, followed by the further development of hypertrophy, in relation to the increase of ventricular weight. At the “critical weight” the progressive increase of cellular diameter, which is less than the theoretical value, abruptly ends and then decreases considerably. In contrast, this same phenomena is not seen for the cell length. The myocardial cell length shows a constant gradual increase always greater than the theoretical value regardless of ventricular weight. For this reason the cellular hyperplasia specifically presents an increase in cellular length beyond the increase in cellular diameter, which is reduced. A multiplication of myocardial nuclei beyond the critical weight was also observed. The results obtained are of physiopathological significance owing to modifications of the capillary network and the interstitial tissues. A histocytometric study of 42 left ventricles was carried out. The cases consisted of normal hearts as well as a number of hypertrophic hearts which were progressively heavier in weight. The results of this study were analyzed by computer. We found an increase in myocardial cell size correlated with an increase in the ventricular free wall weight, up to a critical weight of 250 g. Beyond that critical weight, cellular hyperplasia was evident, followed by the further development of hypertrophy, in relation to the increase of ventricular weight. At the “critical weight” the progressive increase of cellular diameter, which is less than the theoretical value, abruptly ends and then decreases considerably. In contrast, this same phenomena is not seen for the cell length. The myocardial cell length shows a constant gradual increase always greater than the theoretical value regardless of ventricular weight. For this reason the cellular hyperplasia specifically presents an increase in cellular length beyond the increase in cellular diameter, which is reduced. A multiplication of myocardial nuclei beyond the critical weight was also observed. The results obtained are of physiopathological significance owing to modifications of the capillary network and the interstitial tissues.