The right coronary artery, having a normal diameter, without atherosclerosis, ended on the ... surface, in the superior third of the posterior interventricular groove.
Sudden death due to arrhythmogenic right ventricular displasia
AUTHORS: D. Dermengiu , S.Dermengiu , M.Costache , S.Hostiuc , L.Zarma , M.Ceausu 1 National Institute of Legal Medicine, Bucharest, Romania, 2 Carol Davila University of Medicine and Pharmacy, Bucharest, Romania, 3 C.C.Iliescu Institute of Cardiology, Bucharest, Romania 1
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Arrhythmogenic right ventricular cardiomyopathy is a genetically transmitted cardiac disorder, characterized by increased myocardial instability and an increased risk for severe ventricular arrhythmias and sudden death. Histologically there are two main types: fatty, associated with sudden death at rest, and fibrofatty, associated with sudden death during exercise. The purpose of this poster is to present a sudden death caused by an association of a fibrofatty type of arrhythmogenic right ventricular cardiomyopathy in a young athlete, associated with a hemodynamically significant myocardial bridging on the left anterior descending artery, the latter causing an atypical distribution pattern of the fibrofatty infiltration, that posed diagnostic difficulties.
CASE REPORT A 25 year-old man collapsed on the football field and was pronounced dead by the ambulance about 30 minutes later. He was a professional football player until a year ago, when he interrupted this activity as he was diagnosed with hepatitis. Six months ago he had another blackout on the football field. As he was often feeling tired and had thoracic pains, he went to a cardiology hospital, seven and than one month before his death. Both examinations revealed bradycardia, a QRS angle of 90 degrees, EVs, diffuse hypovoltage, and repolarization abnormalities in the anterior territory (V1-V4), and flat T waves in all derivations. The ECG suggested a high probability of cardiomiopathy, either primary or ischemic, with a possible pericardial involvement, and the physicians recommended cardiac echography, myocardial scintigraphy, cardiac MRI, and coronarography. The patient refused these additional examinations. During the forensic autopsy was identified a left ventricle with an intense pale area, subendocardial, at the level of the interventricular septum. The thickness of the interventricular septum was 1.6-1.8 cm. The myocardial tissue contained numerous yellowish stripes, with areas of confluence and dissection. The right ventricle had a thickness of 0.1-0.3 cm, with an irregular pattern of the wall, with significant replacement of the myocardial tissue with adipose formations. The left anterior descendent coronary artery had a significant myocardial bridging, starting at about 2cm from the origin and extending down about 7cm, with a thickness varying from 0.2 to 0.6 cm. The circumflex artery finishes on the pulmonary face of the left ventricle. The right coronary artery, having a normal diameter, without atherosclerosis, ended on the diaphragmatic surface, in the superior third of the posterior interventricular groove. Cardiac histological examination showed interstitial vascular edema, with hypoxic myocardial lesions, significant subepicardial lipomatosis, with extension in the adjacent myocardium. Trichrome Masson stain showed mild-moderate interstitial and perivascular lipomatosis, a pattern suggestive for ARVC.
Figure 1. Fatty infiltration and dilatation of the right ventricle
DISCUSSIONS Even if the sudden deaths in athletes is a considered a rare phenomenon, with an estimated prevalence of between less than 1/100.000 cases[1] and about 3.5/100.000 cases[2], recent reports suggests that the cardiovascular risks associated with professional sports are significantly underestimated[3]. The presence of structural heart diseases, like hypertrophic cardiomyopathy or ARVC, even if only probable, should forbid the practice of performance sports[4]. As ARVC is one of the most frequent causes of sudden death in professional athletes[4], every athlete should be routinely checked for it, especially as most screening tests are readily available. In our case the ECG suggested the probability of a severe cardiovascular disorder (most likely a cardiomyopathy), that would normally forbid that person to go on the football court. However, the patient has not followed the medical recommendation, nor in restricting strenuous physical activities, nor in further researching the cause of the electrical abnormalities. Histologically, ARVC has two main phenotypes: - fatty (lipomatous) - transmural adiposus infiltration, with pseudo-hypertrophy of the right ventricle, affecting mostly the anterolateral and infundibular regions of the right ventricle. The postero-inferior part of the right ventricle and the left ventricle are usually normal. Histologically there is identifiable a fatty infiltration, with rare foci of fibrosis, and normal residual myocytes. Sudden death is not linked with an increased physical activity (sudden death at rest). - fibrofatty - the wall is thinner, often translucent, aneurisms are present in nearly half the cases, usually located in the apex cordis, infundibulum or the postero-inferior wall (the triangle of the right ventricular dysplasia). Septal involvement is rare but the left ventricle is affected in almost half the cases. Histologically are identifiable fibro-fatty infiltration, myocyte degeneration, apoptosis, and T-cell lymphocyte inflammatory infiltrate[5-11]. Out patient had the fibrofatty type of ARVC, that is known to be associated with an increased risk of sudden death during strenuous activities. Moreover, the patient had a hemodynamically significant myocardial bridging on the left anterior descendant artery. The involvement of the interventricular septum, with increased fibrosis and lipomatosis, may be, at least partially caused by the myocardial bridge[12], explaining why the patient had increased fibrolipomatosis in this area, known to be rarely involved in ARVC. References 1. Chandra N, Bastiaenen R, Papadakis M, Sharma S. Sudden Cardiac Death in Young Athletes. Journal of the American College of Cardiology 2013,61:1027-1040. 2. Harmon KG, Asif IM, Klossner D, Drezner JA. Incidence of sudden cardiac death in national collegiate athletic association athletes. Circulation 2011,123:1594-1600. 3. Pelliccia A, Fagard R, Bjornstad HH, Anastassakis A, Arbustini E, Assanelli D, et al. Recommendations for competitive sports participation in athletes with cardiovascular disease - A consensus document from the Study Group of Sports Cardiology of the Working Group of Cardiac Rehabilitation and Exercise Physiology and the Working Group of Myocardial and Pericardial Diseases of the European Society of Cardiology. European Heart Journal 2005,26:1422-1445. 4. Thiene G, Nava A, Corrado D, Rossi L, Pennelli N. Right Ventricular Cardiomyopathy and Sudden-Death in Young-People. New England Journal of Medicine 1988,318:129-133. 5. Racette S, Sauvageau A. 1. Arrhythmogenic right ventricular cardiomyopathy/dysplasia mimicking rape homicide: A case report. Medicine Science and the Law 2005,45:356-360. 6. de la Grandmaison GL, Le Bihan C, Durigon M. Assessment of right ventricular lipomatosis by histomorphometry in control adult autopsy cases. International Journal of Legal Medicine 2001,115:105-108. 7. Tabib A, Loire R, Miras A, Thivolet-Bejui F, Timour Q, Bui-Xuan B, et al. Unsuspected cardiac lesions associated with sudden unexpected perioperative death. European Journal of Anaesthesiology 2000,17:230-235.
Figure 2. Hemodynamically significant myocardial bridging on LAD
Figure 3. Fatty infiltration and severe interstitial fibrosis in the RV (Masson, 4x). Inlet - severe fatty infiltration in the RV (HE, 4x) 8. Tabib A, Loire R, Chalabreysse L, Meyronnet D, Miras A, Malicier D, et al. Circumstances of death and gross and microscopic observations in a series of 200 cases of sudden death associated with arrhythmogenic right ventricular cardiomyopathy and/ or dysplasia. Circulation 2003,108:3000-3005. 9. Tabib A, Miras A, Taniere P, Loire R. Undetected cardiac lesions cause unexpected sudden cardiac death during occasional sport activity - A report on 80 cases. European Heart Journal 1999,20:900-903. 10. Fornes P, Lecomte D. Pathology of sudden death during recreational sports activity - An autopsy study of 31 cases. American Journal of Forensic Medicine and Pathology 2003,24:9-16. 11. D'amati G, Leone O, Di Gioia CRT, Magelli C, Arpesella G, Grillo P, et al. Arrhythmogenic right ventricular cardiomyopathy: Clinicopathologic correlation based on a revised definition of pathologic patterns. Human Pathology 2001,32:1078-1086. 12. Hostiuc S, Curca GC, Dermengiu D, Dermengiu S, Hostiuc M, Rusu MC. Morphological changes associated with hemodynamically significant myocardial bridges in sudden cardiac death. The Thoracic and cardiovascular surgeon 2011,59:406-410
