A retrospective study of postmortem heart weight in an adult Norwegian population

A statistical study of postmortem heart weight in Chinese adults

INTRODUCTION

Objective assessment of cardiac hypertrophy in forensic pathology practice is of great significance for forensic pathologists, for whom reference values for normal heart weights are needed. Developed regions such as Europe, the United States, and Japan recalculate the weight of human organs at regular intervals, but in China, there has been no systematic calculation of the weights of human organs since 2006.

AIMS

To statistically analyse the heart weight of Chinese adults postmortem and obtain a reference range.

MATERIALS AND METHODS

4170 adult autopsy reports were collected from 12 forensic departments in 10 provinces in China. The causes of death were classified by sex, and heart weight and the heart weight/body height ratio reference values were further calculated according to different body mass index and body heights. Finally, the cutoff value of cardiac hypertrophy in Chinese adults was calculated.

RESULTS

In the group of non-cardiovascular disease causes of death, the cardiac weight of the electric death group was higher, while the heart weight of the prolonged bed-rest group was significantly reduced. After the electric death and prolonged bed-rest groups were excluded, heart weight, the heart weight/body height ratio, and cutoff values for cardiac hypertrophy were further classified and analysed according to body mass index. The mean reference values for heart weight in men and women with normal weight status were 325.82 ± 41.60 g and 286.39 ± 44.84 g, and the heart weight/body height ratios were 1.95 ± 0.23 in men and 1.82 ± 0.27, respectively. The cutoff values for cardiac hypertrophy were 387.35 g for men and 346.80 g for women.

CONCLUSION

The heart weight reference values of both sexes in this study were significantly higher than those in 2006, which is considered related to the development of China's economy and the improvement of people's living standards. This study also suggests the need for a new round of statistical surveys and updated data on the weight of other organs.

Cardiac Enlargement in a Medicolegal Autopsy Setting

ABSTRACT

A key element for diagnosing cardiac enlargement in an autopsy setting is relevant heart weight references. However, most available references are to a large extent not representative of a medicolegal autopsy population, implying that reference weights are likely lower than those in the relevant population.To establish more applicable heart weight references in a medicolegal autopsy population, we designed a heart weight model that accounts for undiagnosed cardiac enlargement using data from 11,897 nontraumatic Swedish medicolegal autopsy cases autopsied between 2010 and 2019. The model was validated in 296 nonobese young adult suicidal hanging cases.For a decedent of average height (174 cm), the evidence that a heart weight was enlarged reached weak support at approximately 430 g, substantial support at approximately 480 g, and strong support at 520 g. The modeled prevalence of cardiac enlargement was very high among elderly and obese decedents.We believe that our model is more applicable in a medicolegal setting than those previously published. The presented quantification of the degree of uncertainty regarding diagnosis can help the pathologist in diagnosing cardiac enlargement. To facilitate the use of this model, we also made it available through a simple online tool ( https://formedum.shinyapps.io/HeartWeightCalc/ ).

Obesity Cardiomyopathy in Sudden Cardiac Death: A Distinct Entity? A Comparative Study

Background

Obesity cardiomyopathy (OCM) can be associated with sudden cardiac death (SCD) but its pathologic features are not well described.

Objectives

The objective of this study was to characterize the clinical and pathological features of OCM associated with SCD.

Methods

This was a retrospective case control autopsy study. OCM was identified by an increased heart weight (>550 g in males; >450 g in females) in individuals with obesity (body mass index [BMI] ≥30 kg/m2) in the absence of other causes. Cases of OCM with SCD were compared to sex and age matched SCD controls with obesity or with normal weight (BMI 18.5-24.9 kg/m2) and morphologically normal hearts. Autopsy measures included: heart weight, atrial dimensions, ventricular wall thickness, and epicardial adipose tissue. Fibrosis was assessed microscopically.

Results

Of 6,457 SCD cases, 53 cases of OCM were identified and matched to 106 controls with obesity and 106 normal weight controls. The OCM mean age at death of individuals with OCM was 42 ± 12 with a male predominance (n = 34, 64%). Males died younger than females (40 ± 13 vs 45 ± 10, P = 0.036). BMI was increased in OCM cases compared to controls with obesity (42 ± 8 vs 35 ± 5). The average heart weight was 598 ± 93 g in OCM. There were increases in right and left ventricular wall thickness (all P < 0.05) in OCM cases compared to controls. Right ventricular epicardial fat was increased in OCM compared to normal weight controls only. Left ventricular fibrosis was identified in 7 (13%) cases.

Conclusions

OCM may be a specific pathological entity associated with SCD. It is most commonly seen in young males with increased BMI.

Effect of sex, age and body measurements on heart weight, atrial, ventricular, valvular and sub-epicardial fat measurements of the normal heart

AIMS

Descriptive morphological studies of the normal heart are lacking. Previous autopsy studies have focused mainly on heart weight. We characterize the normal heart by providing normal dimensions of the atria, ventricles, valves and sub-epicardial fat, comparing the findings in terms of sex, age and body measurements.

METHODS

From 3602 referrals to our cardiovascular pathology unit, pathological criteria used for the classification of a morphologically normal heart were a weight of below 500 grams in males, and below 400 grams in females. Diseased hearts were excluded on anatomical and histological evaluation.

RESULTS

We diagnosed 1062 morphologically normal hearts. Mean age at death was 34±12, with a male predominance (701, 66%). Age was similar in females and males (35±13 vs 34±12). Females had a significantly lower heart weight (285±55 vs 374±64). Sex was an independent predictor of most measurements. The atrial and ventricular cavities were significantly larger in males. All ventricular measurements of muscle thickness were larger in males. All valvular circumferences were larger in males. In contrast, sub-epicardial fat was significantly thicker in females in 6 of 7 regions. This is the first study to provide a calculator to give expected values according to sex, age, height and weight.

CONCLUSIONS

Major differences between the sexes exist in the morphologically normal heart. These variations should be considered when assessing cardiac structure in imaging for risk stratification and diagnosis in the cardiomyopathies, as well as in treatment outcomes.

Repository Describing the Anatomical, Physiological, and Biological Changes in an Obese Population to Inform Physiologically Based Pharmacokinetic Models

Background

Obesity is associated with physiological changes that can affect drug pharmacokinetics. Obese individuals are underrepresented in clinical trials, leading to a lack of evidence-based dosing recommendations for many drugs. Physiologically based pharmacokinetic (PBPK) modelling can overcome this limitation but necessitates a detailed description of the population characteristics under investigation.

Objective

The purpose of this study was to develop and verify a repository of the current anatomical, physiological, and biological data of obese individuals, including population variability, to inform a PBPK framework.

Methods

A systematic literature search was performed to collate anatomical, physiological, and biological parameters for obese individuals. Multiple regression analyses were used to derive mathematical equations describing the continuous effect of body mass index (BMI) within the range 18.5–60 kg/m² on system parameters.

Results

In total, 209 studies were included in the database. The literature reported mostly BMI-related changes in organ weight, whereas data on blood flow and biological parameters (i.e. enzyme abundance) were sparse, and hence physiologically plausible assumptions were made when needed. The developed obese population was implemented in Matlab^® and the predicted system parameters obtained from 1000 virtual individuals were in agreement with observed data from an independent validation obese population. Our analysis indicates that a threefold increase in BMI, from 20 to 60 kg/m², leads to an increase in cardiac output (50%), liver weight (100%), kidney weight (60%), both the kidney and liver absolute blood flows (50%), and in total adipose blood flow (160%).

Conclusion

The developed repository provides an updated description of a population with a BMI from 18.5 to 60 kg/m² using continuous physiological changes and their variability for each system parameter. It is a tool that can be implemented in PBPK models to simulate drug pharmacokinetics in obese individuals.

Organ pathologies detected post-mortem in patients receiving opioid agonist treatment for opioid use disorder: a nation-wide 2-year cross-sectional study

AIMS

To document organ pathologies detected post-mortem in patients receiving opioid agonist treatment for opioid use disorder and estimate the extent to which individual characteristics are associated with pulmonary, cardiovascular, hepatic or renal pathologies.

DESIGN

Two-year cross-sectional nation-wide study.

SETTING

Norway.

PARTICIPANTS

Among all 200 patients who died during opioid agonist treatment between 1 January 2014 and 31 December 2015, 125 patients (63%) were autopsied. Among these, 122 patients (75% men) had available autopsy reports and were included. The mean age at the time of death was 48 years.

MEASUREMENTS

Information on pulmonary, cardiovascular, hepatic and renal pathologies were retrieved from forensic or medical autopsy reports, with no (0) and yes (1) as outcome variables and age, sex and body mass index as covariates in logistic regression analyses.

FINDINGS

Pathologies in several organs were common. Two-thirds (65%) of the decedents had more than two organ system diseases. The most common organ pathologies were chronic liver disease (84%), cardiovascular disease (68%) and pulmonary emphysema (41%). In bivariate analyses, only older age was associated with any pulmonary pathology [odds ratio (OR) = 1.06; 95% confidence interval (CI) = 1.01-1.10], cardiovascular pathology (OR = 1.11; 95% CI = 1.05-1.17) and renal pathology (OR = 1.05; 95% CI = 1.00-1.11). Older age remained independently associated with cardiovascular pathology (OR = 1.10; 95% CI = 1.04-1.16) and renal pathology (OR = 1.06; 95% CI = 1.01-1.12) adjusted for body mass index and sex.

CONCLUSIONS

Among autopsied Norwegians who died during opioid agonist treatment in 2014 and 2015, two-thirds had more than two organ system diseases, despite their mean age of 48 years at the time of death. Older age was independently associated with at least one cardiovascular or renal pathology after adjusting for sex and body mass index.

Cardiac hypertrophy at autopsy

Since cardiac hypertrophy may be considered a cause of death at autopsy, its assessment requires a uniform approach. Common terminology and methodology to measure the heart weight, size, and thickness as well as a systematic use of cut off values for normality by age, gender, and body weight and height are needed. For these reasons, recommendations have been written on behalf of the Association for European Cardiovascular Pathology. The diagnostic work up implies the search for pressure and volume overload conditions, compensatory hypertrophy, storage and infiltrative disorders, and cardiomyopathies. Although some gross morphologic features can point to a specific diagnosis, systematic histologic analysis, followed by possible immunostaining and transmission electron microscopy, is essential for a final diagnosis. If the autopsy is carried out in a general or forensic pathology service without expertise in cardiovascular pathology, the entire heart (or pictures) together with mapped histologic slides should be sent for a second opinion to a pathologist with such an expertise. Indication for postmortem genetic testing should be integrated into the multidisciplinary management of sudden cardiac death.

[A retrospective mortality analysis of natural deaths of the 65+ generation based on postmortem autopsies performed at the Institute of Legal Medicine in Frankfurt am Main during two periods]

BACKGROUND AND AIM OF THE STUDY

In Germany, a constant demographic change is taking place, which leads to an increasing aging of the society. The present study aimed to analyze natural deaths occurring at an age of ≥ 65 years, since health vulnerability in this age group is gaining importance.

MATERIAL AND METHODS

Autopsy reports of the Institute of Forensic Medicine, University Hospital of the Goethe University Frankfurt/Main, Germany, were retrospectively evaluated regarding natural death cases of ≥ 65-year-olds in a time comparison (period I: 2000-2002; period II: 2013-2015).

RESULTS

During both periods, a total of 1206 autopsies concerning this age group were performed. Among these, 404 cases (33.5%) of unnatural death and 39 cases (3.2%) of a combination of natural and unnatural death were recorded; in 94 cases (7.8%), the manner of death could not be elucidated. The majority (n = 669; 55.5%) included cases of natural death. In the largest group of these (n = 350; 52.3%), cardiac causes of death were predominant, followed by 132 (19.7%) respiratory and 47 (7.0%) abdominal causes of death. In addition, 37 (5.5%) cases of malignant neoplasms, 33 (4.9%) of ruptures of large vessels, 33 (4.9%) of cerebral, and 37 (5.5%) other cases of natural death were noted. A significant decrease of cardiac causes of death was observed in the comparison of periods I and II. In particular, there was a significant decrease in high-grade occlusive coronary sclerosis. Moreover, there were significant differences between both sexes. Men had significantly more bypasses, stents and heart scars and suffered a myocardial infarction about 10 years earlier than women.

CONCLUSION

The results of the present study are largely consistent with the literature. The decrease in numbers of cardiac deaths may be attributed to increasingly better medical care and to a significantly higher rate of stent implantation. Especially in times of pandemics, the role of forensic gerontology will become more important.

Cutoff value for hypertrophic heart weight in the Japanese population

BACKGROUND

Cardiac hypertrophy is a clinical risk factor for cardiovascular death (CVD) frequently recorded in autopsy reports, but the diagnostic criteria for the condition have not been clearly-established for autopsy. This study aimed to estimate the cutoff value for hypertrophic heart weight that can efficiently assist the postmortem diagnosis of CVD.

METHODS

We analyzed accumulated autopsy data from 3534 individuals aged 0-101 years.

RESULTS

We found that heart weight increased linearly with a person's age until 20 years, after which it remained stable. The mean heart weight in CVD cases was 473 g in men and 379 g in women. The mean heart weight in non-CVD cases was 385 g in men and 320 g in women. Receiver operating characteristic curve analysis for CVD assessment revealed that the cutoff value of heart weight was 407 g (odds ratio of 4.2) in men and 327 g (2.6) in women, and that of heart weight/body height was 2.38 g/cm (4.0) in men and 2.15 g/cm (2.6) in women, respectively. Overall, heart weight was a more useful predictor of CVD in men than in women. In logistic regression analysis, the predictive power of heart weight for CVD was higher than that of body mass index in both sexes.

CONCLUSION

Thus, the criteria for hypertrophic heart weight are practical and useful for autopsy recordings, and it can be helpful for postmortem diagnosis of CVD. Our report is the first to reveal the cutoff value for hypertrophic heart weight in the Japanese population.

Prevalence of Abnormal Heart Weight After Sudden Death in People Younger than 40 Years of Age

Background After sudden cardiac death in people aged <40 years, heart weight is a surrogate for cardiomegaly and a marker for cardiomyopathy. However, thresholds for cardiomegaly based on heart weight have not been validated in a cohort of cases of sudden cardiac death in young people. Methods and Results We surveyed medical examiner offices to determine which tools were used to assess heart weight norms. The survey determined that there was no gold standard for cardiomegaly (52 centers reported 22 different methods). We used a collection of heart weight data from sudden deaths in the Northwestern Sudden Death Collaboration (NSDC) to test the 22 methods. We found that the methods reported in our survey had little consistency: they classified between 18% and 81% of NSDC hearts with cardiomegaly. Therefore, we obtained biometric and postmortem data from a reference population of 3398 decedents aged <40 years. The reference population was ethnically diverse and had no known cardiac pathology on autopsy or histology. We derived and validated a multivariable regression model to predict normal heart weights and a threshold for cardiomegaly (upper 95% CI limit) in the young reference population (the Chicago model). Using the new model, the prevalence of cardiomegaly in hearts from the NSDC was 19%. Conclusions Medical examiner offices use a variety of tools to classify cardiomegaly. These approaches produce inconsistent results, and many overinterpret cardiomegaly. We recommend the model proposed to classify postmortem cardiomegaly in cases of sudden cardiac death in young people.