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Med Leg J OnlineFirst, published on May 20, 2014 as doi:10.1177/0025817213517353

Original Article

Sudden death due to coronary artery insufficiency as a result of massive cardiomegaly – a case report

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Basappa S Hugar, S Praveen, J Vinay and Akshith Raj S Shetty

Abstract Forensic pathologists encounter a wide range of deaths due to natural causes. Natural deaths can be sudden and unexpected, occurring in apparently healthy people. All such cases have to be investigated and a medico-legal autopsy should be conducted to ascertain the cause of death, and to rule out any criminal cause of death. Here, we report a case of a 46-year-old male who collapsed at his workplace and died. There was no history of significant natural disease. The case was investigated due to the suddenness of his death and absence of a history of significant medical illness. An autopsy revealed that the death was due to coronary artery insufficiency as a result of massive cardiomegaly, although there was absence of significant occlusion of the coronary arteries. Keywords Forensic pathology, sudden natural death, sudden cardiac death, massive cardiomegaly, coronary artery insufficiency.

Introduction Cardiac hypertrophy was viewed as a compensatory response to haemodynamic changes; however, cumulative evidence obtained from studies using more advanced technologies in human patients and animal models suggests that cardiac hypertrophy is a maladaptive process of the heart in response to intrinsic and extrinsic stresses. Cardiomegaly is a frequent cause of sudden cardiac death (SCD), and is highly associated with obesity.1 Symptoms vary widely in people with an enlarged heart. Some may never have symptoms. Others may have mild symptoms that remain unnoticed for years. In 4–5% of all SCDs a cause of death cannot be ascertained, even after a comprehensive post-mortem, toxicological screening and cardiac pathological examination. These are classified as sudden arrhythmic death syndrome. The cardiovascular lesions responsible for ventricular hypertrophy include: volume loads such as an inflow valve regurgitation and left-to-right shunts; pressure loads such as semilunar valvular stenosis or systemic hypertension and certain myocardial diseases such as coronary atherosclerosis and the cardiomyopathies. Idiopathic myocardial hypertrophy is a puzzling condition characterised by cardiac enlargement and progressive decompensation occurring in previously healthy individuals. The sole pathological finding is left ventricular hypertrophy (LVH) with or without varying degrees of mural fibrosis. Valvular lesions are absent. The coronary arteries are widely patent and

atheromata are either absent or insignificant. No clinical or laboratory finding is of specific aid in diagnosis.2 Here, we report a case of sudden death where the heart weighed 880 g with insignificant coronary artery occlusion and idiopathic LVH. The normal male human heart weighs around 300 g.

Case report A 46-year-old male collapsed suddenly at his workplace and was brought in dead to a tertiary care hospital. A post-mortem was performed. The body was moderately built and obese. Post-mortem staining was present over the back and was fixed; generalised rigour mortis was present. No demonstrable external or internal injuries were noted at autopsy. The heart was enlarged, weighing 880 g (Figure 1) and the surface showed multiple areas of fibrosis (old healed infarcts) (Figure 2). The ventricular walls were thickened with the left ventricular wall showing areas of old healed infarcts. The thickness of the left ventricular wall was 2.2 cm (Figure 3) and that of the right ventricular wall 1.1 cm. On dissection of the Department of Forensic Medicine, MS Ramaiah Medical College, Bangalore, India Corresponding author: Dr. Basappa S Hugar, Associate Professor, Department of Forensic Medicine, MS Ramaiah Medical College, MSRIT Post, MSR Nagar, Bangalore – 560054, India. Email: [email protected]; [email protected]

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Figure 1 Enlarged heart. Figure 3 Hypertrophied left ventricular wall (thickness – 2.2 cm).

Figure 2 Surface of heart showing multiple areas of fibrosis (old healed infarcts).

coronary arteries, the left anterior descending artery was patent (Figure 4). The left circumflex artery and the right coronary artery were thickened and narrowed by 10% due to atheromatous plaque. The atrio-ventricular valve, semilunar valves and the papillary muscles were intact (Figure 5). The lungs were oedematous and congested. The stomach contained 50 mL of clear fluid, there was no unusual smell and the mucosa was normal. Other organs were intact and congested. Histo-pathological examination confirmed myocardial hypertrophy and old healed infarcts. No other pathology was detected. The toxicological screen of the viscera and blood was negative.

Discussion Cardiomegaly is an enlargement of the heart due either to myocardial hypertrophy, chamber dilatation or

Figure 4 Patent left anterior descending coronary artery.

both. Cardiomegaly (heart weight >400 g) was recorded in 11.4% of autopsies in 1998 (403 cases of total 3541 autopsies), 12.4% in 1999 (444 cases of total 3567 autopsies) and 12.8% in 2000 (472 cases of total 3684 autopsies). The cause of cardiomegaly in the majority (55%) of cases was essential hypertension.3 In the present case, there was massive cardiomegaly (heart weight 880 g) with significant LVH (Figure 1). The increase in the left ventricular mass is an independent prognostic factor for cardiovascular mortality, mortality due to all causes and for sudden death. Hypertensive individuals with LVH present a 2-to-5-fold increase in fatal and non-fatal cardiovascular events when compared with those with hypertension only.4

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Hugar et al.

3 There was no valvular pathology (Figure 5) evident at autopsy; valvular pathologies like mitral valve annulus calcification can sometimes be associated with cardiomegaly and sudden death.10 In the present case, there was massive cardiomegaly (heart weight 880 g) with significant LVH (Figure 1). This would cause disproportion between the blood supply and the demand by the heart although the coronary arteries were patent. Thus, death could have resulted from arrhythmias arising out of ischaemia as a result of coronary artery insufficiency. Hence, the cause of death was considered to be due to ‘‘coronary artery insufficiency as a result of massive cardiomegaly’’, and so a natural death.

Conclusion

Figure 5 Intact mitral valve and no papillary muscle hypertrophy.

In this case, the patient may have been suffering from hypertension for many years, which was not noticed because he did not have any symptoms of significant health problems. Thus he was not on any medication. LVH can be a marker of silent coronary disease; furthermore, cardiac hypertrophy may predispose to ventricular arrhythmias even in the absence of coronary artery disease.5 When the heart is macroscopically normal, review of previous electrocardiograms is the most helpful guide and may disclose conditions such as a long QT interval or pre-excitation.6 In this case, previous electrocardiograms were not available for review. Cardiac hypertrophy itself is a risk factor for SCD.7 Hypertrophic cardiomyopathy cases are classified in the presence of LVH, with either myofibrillary disarray or interstitial fibrosis on histological examination. Cases with LVH without myofibrillary disarray or fibrosis were described as idiopathic LVH.8 Hypertrophic (obstructive) cardiomyopathy presents an apparently unique disorder of ventricular muscle associated with massive hypertrophy of a particular type, and increased ventricular stiffness due to the massive muscle. The hypertrophy has no useful adaptive function and is often associated with out-flow tract obstruction of the left ventricle.9 Cardiomegaly with presumed hypertensive, multifactorial or unknown cause was the sole arrhythmogenic substrate in 38% of men and 49% of women (p ¼ 0.003).1

Symptoms vary widely in people with cardiomegaly. Some may never have symptoms. Others may have mild symptoms that remain undiagnosed for years. Cardiomegaly is a frequent cause of SCD, and is highly associated with obesity. Thus, isolated cardiomegaly encountered at autopsy without underlying significant pathology of the heart should be considered as the cause of death in itself. References 1. Tavora F, Zhang Y, Zhang M, et al. Cardiomegaly is a common arrythmogenic substrate in adult sudden cardiac deaths, and is associated with obesity. Pathology 2012; 44: 187–191. 2. Spodick DH and Littmann D. Idiopathic myocardial hypertrophy. Am J Cardiol 1958; 1: 610–623. 3. Akosa AB and Armah H. Cardiomegaly in Ghana: an autopsy study. Ghana Med J 2005; 39: 122–127. 4. Rodrigues SL, Pimentel EB, Mill JG, et al. Cardiac ventricular weights recorded at the autopsy of healthy subjects who died of external causes. Arq Bras Cardiol 2007; 89: 252–257. 5. Schillaci G, Verdecchia P, Borgioni C, et al. Association between persistent pressure overload and ventricular arrhythmias in essential hypertension. Hypertension 1996; 28: 284–289. 6. Davies MJ. Pathological view of sudden cardiac death. Br Heart J 1981; 45: 88–96. 7. Kang YJ. Cardiac hypertrophy: a risk factor for QTprolongation and cardiac sudden death. Toxicologic Pathol 2006; 34: 58–66. 8. Margey R, Roy A, Tobin S, et al. Sudden cardiac death in 14- to 35-year olds in Ireland from 2005 to 2007: a retrospective registry. Europace 2011; 13: 1411–1418. 9. Goodwin JF. Hypertrophic diseases of the myocardium. Prog Cardiovasc Dis 1973; 16: 199–238. 10. Quick E and Byard RW. Mitral annulus calcification and sudden death. J Forensic Leg Med 2013; 20: 204–206.

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Sudden death due to coronary artery insufficiency as a result of massive cardiomegaly--a case report.

Forensic pathologists encounter a wide range of deaths due to natural causes. Natural deaths can be sudden and unexpected, occurring in apparently hea...
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