Morphometric quantification revealed that myocyte volumes in subepicardial and subendocardial left ventricular tissue of hypertrophic hearts were 78% and 43% higher, respectively, than normal hearts.
Observational (n=21)
A modified azan staining procedure allows accurate and reproducible morphometric quantification of myocyte dimensions, revealing transmural differences in myocyte hypertrophy in 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. Myocyte width, cut surface area, length, and volume were significantly correlated with left ventricular weight with residual errors of 5%, 5%, 6%, and 8% respectively. The method was applied to 21 human hearts, nine of which had left ventricular hypertrophy. Myocyte width, area, length, and volume both in subepicardial and subendocardial left ventricular tissue were significantly greater in hypertrophic than in normal hearts. Although the mean weight of the hypertrophic hearts exceeded that of normal hearts by 40%, myocyte volumes in subepicardial and subendocardial left ventricular tissue of hypertrophic hearts were higher by 78% and 43% respectively, indicating a transmural difference in the extent of myocyte hypertrophy. The method is accurate and reproducible and gives useful quantitative information on changes in myocyte dimensions during normal cardiac growth as well as in cardiac hypertrophy.
Vliegen et al. (Fri,) conducted a observational in Left ventricular hypertrophy (n=21). Morphometric quantification using modified azan staining vs. Normal hearts was evaluated on Myocyte width, cut surface area, length, and volume. Morphometric quantification revealed that myocyte volumes in subepicardial and subendocardial left ventricular tissue of hypertrophic hearts were 78% and 43% higher, respectively, than normal hearts.