%0 Journal Article
%T Histologically Measured Cardiomyocyte Hypertrophy Correlates with Body Height as Strongly as with Body Mass Index
%A Richard E. Tracy
%A Gary E. Sander
%J Cardiology Research and Practice
%D 2011
%I Hindawi Publishing Corporation
%R 10.4061/2011/658958
%X Cardiac myocytes are presumed to enlarge with left ventricular hypertrophy (LVH). This study correlates histologically measured myocytes with lean and fat body mass. Cases of LVH without coronary heart disease and normal controls came from forensic autopsies. The cross-sectional widths of myocytes in H&E-stained paraffin sections followed log normal distributions almost to perfection in all 104 specimens, with constant coefficient of variation across the full range of ventricular weight, as expected if myocytes of all sizes contribute proportionately to hypertrophy. Myocyte sizes increased with height. By regression analysis, height2.7 as a proxy for lean body mass and body mass index (BMI) as a proxy for fat body mass, exerted equal effects in the multiple correlation with myocyte volume, and the equation rejected race and sex. In summary, myocyte sizes, as indexes of LVH, suggest that lean and fat body mass may contribute equally. 1. Introduction Early reports concerning myocyte size in the human left ventricle, relying heavily upon autopsy specimens [1每3], often found that [4] ※the individual contractile muscle cells ＃ are roughly cylindrical ＃ measuring 17 to 25ˋ米m in diameter and 60 to 140ˋ米m in length,§ giving length to diameter ratio of about 5 to 1. Recent studies, relying on enzymatic isolation of myocytes into suspension from surgical specimens [5每14], commonly model myocytes as elliptic cylinders of variable eccentricities and length to width ratios under assorted conditions [5每7]. Variations between these models, arising from disparate methodologies, call for further inquiry to resolve their causes. Cross-sectional profiles of myocytes, whether isolated or in sections, display a daunting irregularity of outline, especially of major axis, although less so of the minor axis. Measurements of minor axis are therefore emphasized in this report of findings with H&E-stained paraffin sections of forensic autopsy specimens. Left ventricular mass increases in many hyperergopathic states, often culminating in systolic dysfunction [15, 16]. Behavior by the full range of myocyte sizes, and not just their average, merits attention. Several authors [7每10] have reported unimodal distribution curves of myocyte sizes, consistently showing conspicuous upward skewness. These authors did not report statistical curve fitting; however, graphic inspection raised the possibility of log normal fits, which could imply that the smallest and the largest myocytes may all respond alike [7每9], a possibility seldom discussed. Grant et al. [17] stated a rarely encountered
%U http://www.hindawi.com/journals/crp/2011/658958/