Morphometric quantification of myocyte dimensions validated in normal growing rat hearts and applied to hypertrophic human hearts.

To obtain quantitative information on changes in myocyte size in hearts with increased myocardial mass light microscopical morphometry was used in fixed and stained myocardial tissue sections. A modification of the azan staining procedure made longitudinal (sarcolemma) and transverse (intercalated discs) boundaries visible with a contrast that allowed morphometric analysis. The method was validated in left ventricular tissue of rats ranging in age from 4 to 17 weeks.