Association of Cardiomegaly with Coronary Artery Histopathology and its Relationship to Atheroma

Abstract

Aims: Hypertrophied hearts at autopsy often display excessive coronary artery atherosclerosis, but the histopathology of coronary arteries in hearts with and without cardiomegaly has rarely been compared. Methods: In this study, forensic autopsies provided hearts with unexplained enlargement plus comparison specimens. Right coronary artery was opened longitudinally and flattened for formalin fixation and H&E-stained paraffin sections were cut perpendicular to the endothelial surface. The microscopically observed presence or absence of a necrotic atheroma in the specimen was recorded. At multiple sites far removed from any form of atherosclerosis, measurements were taken of intimal thickness, numbers of smooth muscle cells (SMC) and their ratio, the thickness per SMC, averaged over the entire nonatheromatous arterial length. When the mean thickness per SMC exceeded a certain cutoff point, the artery was declared likely to contain a necrotic atheroma. Results: The prevalence of specimens with necrotic atheromas increased stepwise with increasing heart weight, equally with fatal or with incidental cardiomegaly, and equally with hypertension-or obesity-related hypertrophy, rejecting further inclusion of appreciable age, race, or gender effects. The prevalence of specimens with thickness per SMC exceeding the cutoff point was almost always nearly identical to the prevalence of observed necrotic atheroma, showing the two variables to be tightly linked to each other with quantitative consistency across group comparisons of every form. Conclusions: In summary, cardiomegaly, irrespective of the specific cause, seems to accelerate the risk of atheromas, and to do so by first altering the arterial architecture, especially by increasing intimal thickness per SMC. J Atheroscler Thromb, 2011; 18:32-41.

Cardiac Enlargement in a Medicolegal Autopsy Setting

“…When applying previous definitions of cardiac enlargement, 1,4–6 there was a considerable difference in the proportion of cases classified as enlarged (Fig. 1).…”

“…The mean heart weight was considerably lower than in the population in which the model was constructed (mean 329 g, SD 62 vs 447 g, SD 122). The model captured most of the assumed healthy decedents within 1 SD, but the modeled mean heart weight was generally slightly Heart weight ≥400 g Basso et al 1 Heart weight "above known reference values" or 500 g in men and ≥400 g in women Schoppen et al 4 Heart weight "above known reference values" or >350 g in men and >300 g in women or >400 g in men and >350 g in women or >400 g in general or >500 g overall or >5 g/kg body weight overall or in men or >4.5 g/kg body weight in men and >4 g/kg body weight in women or >2 times the measured body weight (in pounds) in g Tracy 5 Heart weight ≥450 g in men and ≥400 g in women higher than the actually measured heart weight (median difference, 43 g) (Fig. 4).…”

“…Cardiac enlargement—herein defined as “increased heart weight”*—is an important marker of heart disease and can help to determine the cause and manner of death 1–5 . In cases involving enlarged hearts, diligent efforts must be made to ascertain the etiology 1 .…”

“…However, in some cases, the cause remains elusive, and the death might instead be attributed to the cardiac enlargement itself 1 . Agreement on what counts as cardiac enlargement is limited 1,3–6 (Table 1), but there is consensus that relevant reference values do represent a key to determine cardiac enlargement 1 . Most reference values are, however, based on populations that are not necessarily representative of the relevant autopsy population in which these references are to be applied, as they are dated, 7–10 limited to unnatural deaths, 11–14 and/or free of major disease 4,13–20 .…”

Hipertensão arterial: estudo Post Mortem na Região Metropolitana de São Paulo

“…Estudos sobre mortalidade são realizados, na maioria das vezes, através de dados histológicos de autópsias, mostrando a hipertensão arterial como fator de risco para mortalidade por doenças cardiovasculares 11,12 . Um estudo realizado em Cuba buscou identificar as causas de óbito relacionadas à hipertensão arterial, utilizando para tal, mais de 6000 declarações de óbitos com diagnóstico de hipertensão, sendo selecionados 1286 com a hipertensão como causa básica do óbito.…”