Forensic medicine aspects of fatal coronary insufficiency with normal coronary arteries

Clinical experiences give examples for the existence of various courses of anginal symptomatology even with cases of sudden heart death demonstrating angiographically normal coronary arteries. Pathogenetically may be considered spasms of regular or little changed coronary arteries, coronary muscle bridges and acute arrhythmias. In cases of recurrent myocardial ischemias an interstitial fibrosis and endocardial fibrosis can be proved histologically in the myocardial supply area. However an acute coronary insufficiency based on rheological and metabolic etiology cannot be found with morphological methods. The results are discussed, considering forensic aspects in cases of competitive causes of death.     

心肌缺血猝死心肌中高迁移率族蛋白B-1的表达研究

目的探讨高迁移率族蛋白B-1(High Mobility Group Box protein 1,HMGB1)在心肌缺血猝死后诊断中的法医学价值。方法收集不同案例心肌蜡块分为疑似早期心肌缺血猝死组(早期梗死组)20例、心肌梗死猝死组(心肌梗死组)15例、冠心病非心源性猝死组(对照组1)10例和正常心肌组(对照组2)10例,应用免疫组织化学二步法染色,观察心肌胞核和胞浆中HMGB1表达,用ImagePro Plus 6.0软件计算HMGB1表达的平均光密度,用SPSS 13.0对表达进行数据统计分析。结果 HMGB1在四组心肌细胞胞核中表达均呈阳性;早期梗死组和心肌梗死组胞浆均呈阳性表达,对照组1和对照组2胞浆呈阴性。各组平均光密度分别为0.3031±0.0557、0.3195±0.0523、0.0252±0.0030、0.0207±0.0029,早期梗死组和心肌梗死组的阳性反应与两个对照组相比存在显著差异(P﹤0.01)。结论 HMGB1可作为早期心肌缺血猝死的一个辅助诊断指标。     

急性心肌缺血猝死心肌中血红素加氧酶-1的表达

目的观察血红素加氧酶-1（HO-1）在急性心肌缺血猝死心肌细胞胞浆中的表达情况。方法应用免疫组织化学技术（SP法）,对27例可疑早期心肌缺血猝死（早期梗死组）、10例心肌梗死猝死（心肌梗死组）、11例冠心病非心性猝死（对照组1）以及10例正常心肌（对照组2）中HO-1的表达进行观察分析。结果早期梗死组与心肌梗死组在心肌细胞胞浆中HO-1均呈强阳性表达,对照组1和对照组2心肌细胞胞浆中HO-1弱阳性表达或无表达。早期梗死组和心肌梗死组与对照组1和对照组2之间心肌细胞内HO-1表达的差异有显著性意义（P（0.01）;镜下各组心肌细胞胞浆内HO-1表达的阳性面积率及平均光密度差别明显。结论 HO-1可以作为急性心肌缺血所致心性猝死的一个诊断指标。     

Relationship of ischemic heart disease to sudden death

A clinicopathological synthesis is presented of the relationship of ischemic heart disease to sudden cardiac death. The immediate pathophysiological process responsible for sudden cardiac death is a lethal arrhythmia, usually ventricular fibrillation. Although significant coronary atherosclerosis is present in most cases of naturally occurring sudden death, available evidence indicates that several mechanisms can be operative in the pathogenesis of the fatal event. These are (1) acute myocardial infarction in a minority of cases; (2) myocardial ischemia, without infarction, which is initiated either by (a) an exertion-induced increase in myocardial oxygen demand or (b) an acute coronary event often involving plaque degeneration and platelet aggregation; and (3) a primary arrhythmia, usually resulting from altered electrical conduction in the setting of a previous myocardial infarction.     

A study of various morphologic variables and troponin I in pericardial fluid as possible discriminators of sudden cardiac death

Pathologists frequently examine victims of sudden cardiac death. In some cases, a firm diagnosis of cardiac-related death can be made based on conclusive gross and histologic findings. In many other cases, we find evidence supportive of, but not diagnostic of, cardiac death (e.g., atherosclerotic coronary artery disease, cardiomegaly, myocardial scarring). A final cohort consists of cases of sudden death with minimal to mild cardiac disease, no other significant pathology, and negative toxicologic studies. This prospective study compared 38 cardiac-related deaths with 52 control cases with respect to concentrations of pericardial cardiac troponin I (cTnI), heart weight, evidence of old and/or recent myocardial injury, and presence of significant coronary artery disease. The influence of documented chest trauma and/or perimortem cardiopulmonary resuscitation (CPR) on levels of cTnI was also analyzed. Even though median cTnI levels were significantly higher in cardiac deaths than in controls (p = .003), cTnI was not found to be a significant predictor of cardiac deaths, as determined by discriminant analysis (p = .52). Heart weight >500 g, evidence of old and recent myocardial injury, and significant coronary artery disease were seen statistically more often in cardiac deaths than in controls (p < or = .005 in each case), and median age was significantly higher in cardiac deaths than in controls (p = .001). Based on a stepwise logistic regression model, significant coronary artery disease, old and recent myocardial injury, and heart weight >500 g were found to contribute significantly to the prediction of cardiac death. Finally, neither chest injury nor CPR significantly affected concentrations of cTnI in pericardial fluid. These data confirm that the presence of acute and remote myocardial injury, significant coronary artery disease, and cardiomegaly (heart weight >500 g) strongly supports the diagnosis of a cardiac-related death. In contrast to a recently published report, we do not find that elevated concentrations of cTnI in pericardial fluid are strong indicators of cardiac-related deaths using our methodology.     

Sudden death due to unsuspected coronary vasculitis.

Coronary artery vasculitis is a well-recognized complication of polyarteritis nodosa and is occasionally seen in other forms of systemic vasculitis. However, involvement of the major epicardial coronary arteries leading to myocardial infarction and death is uncommon. Isolated coronary arteritis is even more rare. We report three cases of sudden death due to myocardial ischemia associated with arteritis of the major coronary arteries. All three decedents were previously healthy young to middle-aged men who had died suddenly after complaints of chest pain and shortness of breath. The autopsy findings and differential diagnoses are presented. Such cases are of particular interest to the medical examiner because of the sudden, unexpected nature of the deaths. An approach to the correct diagnosis is discussed.     

Two consecutive fatal cases of acute myocardial infarction caused by free floating thrombus in the ascending aorta and review of literature

Free floating thrombus in the ascending aorta is an uncommon source of acute myocardial infarction. We report on two cases of young women who died of acute myocardial infarction caused by a free floating thrombus in the sinus of Valsalva obstructing the coronary arteries' ostia. The first case reports on a 30-year-old pregnant woman who anamnestically had episodes with short loss of consciousness and weakness. The second case presents a 37-year-old woman suffering from multiple sclerosis with no previous history of thrombotic events. The review of literature revealed a predominance of women (eight females and three males). Interestingly, the coronary arteries bear no preference concerning the right (RCA) or left coronary artery (LCA) being more often occluded by a free floating thrombus. Especially, younger women (mean age 45.5 years, range 30-59 years) with no history of cardiac symptoms and without atherosclerotic changes seem to be predispositioned. The hypothesis that thrombus formation in cases without plaque disruption may depend on an endothelial erosion which seems to be more common in younger women and promoted by a hyperthrombogenic state is supported by our two cases. A comprehensive literature search revealed, that these are the first two reports on a free floating thrombus being the cause of fatal acute myocardial infarction in a pregnant woman, respectively, a woman suffering from multiple sclerosis.     

Myocardial dysplasia of the right ventricle (Uhl's anomaly) as a possible cause of sudden, unexpected death

Partial absence and fatty replacement of the myocardial compacta of the right ventricular wall was observed in five young male adults, four of whom died suddenly and unexpectedly and one in a car accident. In one of these cases there was only one coronary orifice. Four cases of the so-called Uhl anomaly had histological findings indicating dysmorphic myocardial cells associated with minimal lymphohistiocytic infiltrates within the fatty tissue. In one case, chronic destructive inflammation was a prominent feature. Marked dysmorphic alterations in the myocardial fibers suggested the occurrence of arrhythmic episodes as the main cause of sudden heart failure and death.     

Immunostaining by complement C9: a tool for early diagnosis of myocardial infarction and application in forensic medicine

Before the first 12 hours, diagnosis of early myocardial infarctions is always difficult for forensic pathologists. We tested complement C9 expression in 121 formalin-fixed and paraffin-embedded heart samples by an immunohistochemical procedure. The heart specimens were separated into four groups: 33 cases in group 1 with typical ischemic damages histologically located, 20 cases in group 2 with death related to myocardial infarction on the basis of ischemic presentation on electrocardiogram but no obvious histological ischemic damage, 35 cases in group 3 with severe coronary disease without cause of death found at the autopsy, and 33 cases in group 4 without sign of myocardial infarction and without coronary disease. In the first group, all 33 heart samples showed a well-defined C9 expression in the necrotic areas. The second group in 17 of 20 cases showed positive areas for C9 expression. In the other three heart specimens, only few stained cells were observed whereas the painful symptoms had begun less than 1 h before death. The third group showed C9 immunopositive areas in six of 35 cases, few stained cells in 8 cases, and no C9 deposition in the 21 other cases. The last group showed no staining area. To avoid nonspecific C9 staining due to tissue autolysis, we studied C9 expression during a controlled putrefactive process in four cases included in group 1; staining was found only in infarcted myocardial areas, and was observed up to ten days. Specificity of C9 expression was evaluated to be 100% [89.4 to 100%] and sensitivity to be 85% [62.11 to 96.79%]. In conclusion, evaluation of immunohistochemical expression of C9 appears to be a highly sensitive and specific marker of early myocardial infarction, useful in forensic medicine if survival is more than 1 h after the beginning of myocyte damage.     

冠心病猝死心肌mcl-1蛋白检测及其意义

目的观察冠心病猝死(SCD)心肌mcl-1蛋白产物,探讨其免疫组化检测及其对SCD诊断的意义。方法运用免疫组织化学SABC法,对46例SCD和40例非猝死心肌(有冠心病和无冠心病)中mcl-1蛋白产物进行检测和观察,并比较其差异。结果(1)自症状出现至死亡,时间超过30min的SCD(36例),其心肌组织均出现mcl-1蛋白阳性染色;(2)自症状出现至死亡,时间短于30min的SCD(10例),其心肌组织mcl-1蛋白呈弱阳性染色;(3)冠心病非猝死样本(20例),4例心肌出现微弱的mcl-1蛋白阳性染色,无冠心病非猝死样本(20例)几乎没有出现阳性染色。结论心肌mcl-1蛋白的免疫组化检测可诊断自症状出现至死亡时间超过30min的SCD。     

Cocaine-induced ischemic myocardial disease

Three cases of acute myocardial infarction due to cocaine-related coronary artery disease are presented. Pathogenesis and autopsy findings are discussed.     

Forensic significance of lesions of the sinus node in cases of sudden death of unknown origin

Report on a systematical histological investigation of sinu-atrial nodes in strongly suspected cases of cardiac death in which no pertinent myocardial or coronary changes were found. In over 40% of the cases studied there were histopathological changes in the mixed tissue components of the sinu-atrial node which were highly suggestive of severe or fatal functional impairment.     

A Case of Sudden Infant Death Due to Incomplete Kawasaki Disease

Although Kawasaki disease (KD) is a self‐limiting disease, it may cause sudden cardiac death. Diagnosis of KD is principally based on clinical signs; however, some infant cases do not meet the criteria. Such cases are identified as incomplete KD. The sudden death risk in incomplete KD cases is similar to conventional KD. In our 5‐month‐old case, he had been admitted to a hospital for a fever and suppuration at the site of Bacille de Calmette et Guerin (BCG) vaccination. However, after discharge from the hospital, his C‐reactive protein (CRP) levels declined, he got indisposed and died suddenly. A medico‐legal autopsy revealed myocarditis, coronaritis, platelet‐aggregated emboli in coronary arteries, and myocardial degeneration, suggesting that the fatal myocardial infarction was due to thrombus emboli in the coronary arteries. Forensic pathologists therefore should pay attention to the cardiac pathology originated from incomplete KD as a potential cause in cases of sudden infant death.     

Cytoskeleton immunohistochemical study of early ischemic myocardium

Previous studies on cytoskeletal changes of in vitro and in vivo animal models of ischemic myocardium have suggested the possibility of using alterations in cytoskeleton proteins as an early marker for the post-mortem diagnosis of myocardial ischemia in cases of sudden death due to coronary artery disease (CAD). In the present study, using the technique of ABC-immunohistochemistry, we examine the changes of three cytoskeletal proteins: vinculin, desmin and α-actinin in human myocardial samples taken from 14 cases of CAD sudden death and 13 cases of non-CAD death. Results of these examinations are compared with immunohistochemical changes of myoglobin and histochemical staining of hematoxylin and eosin and phosphotungstic acid, and Masson trichrome. Patchy and extensive loss of the three cytoskeletal proteins was demonstrated in the myocardium of victims who died 1 h or later following the onset of symptoms of ischemic myocardium. The pattern of cytoskeleton change is equivocal in the cases of CAD who died less than 1 h after the onset of symptoms and of the cases of non-CAD. In these cases, no significant histological change was observed. With less non-specific background changes and stronger positive staining, immunohistochemical staining of the three cytoskeletal proteins is more reliable than myoglobin, which has attracted the attention of many pathologists searching for anatomic evidence of ischemic myocardium in coronary artery disease.     

Sudden and unexpected death of a 6-month-old baby with silent heart failure due to anomalous origin of the left coronary artery from the pulmonary artery.

A 6-month-old girl died suddenly without any previous symptoms of heart failure. Autopsy examination showed cardiomegaly (97 g) with a severely fibrotized myocardium. The left coronary artery was originating from the pulmonary artery. Histologically, the myocardium showed myocardial infarcts of different ages, as well as grossly thickened arterial branches due to increased flow in left-right shunt. We suggest that rare anomalies of the coronary arteries should be considered in the autopsies of suspected sudden infant death syndrome cases.     

冠心病猝死的病理学研究——附128例尸检分析

本文报道128例冠心病猝死的法医病理学研究结果。其中冠脉病变4级63例,3级26例,2级29例。3级以上病变者斑块分布多较广泛。各支病变中以左前降支最常见。并发新鲜血栓形成者18例,斑块内出血17例,急性心肌梗死仅2例。36例冠脉斑块有炎性细胞浸润。56例见心肌间质纤维化或小灶疤痕形成。指出虽然我国冠心病发病率较低,但仍是猝死最常见的原因,尤以中壮年男性多见;多数病例无明显诱因而于睡眠中猝死。对冠心病猝死发生的特点、冠脉和心肌病变及病理诊断等进行了分析讨论。     

冠心病猝死心肌纤维连接蛋白免疫组化染色观察

目的研究纤维连接蛋白（FN）免疫组化染色对冠心病猝死（SCD）的病理学诊断价值。方法用兔抗人FN多克隆抗体对人SCD心肌、颅脑损伤和病毒性心肌炎致死者心肌进行FN-SP免疫组化染色观察，用图像分析处理系统对FN免疫组织化学染色阳性反应产物面积定量，所得数据进行统计分析。结果SCD组16例心肌组织内FN大量沉积；颅脑损伤致死组心肌细胞内FN染色阴性，病毒性心肌炎致死组部分心肌细胞内FN阳性；3组心肌细胞内的阳性反应面积存在显著性差异（P〈0．05）。冠心病猝死组阳性反应面积（μm^2）为54143．28±8474．92；颅脑损伤致组阳性反应面积（μm^2）为527．99±105．04；病毒性心肌炎组阳性反应面积（μm^2）为5483．53±1219．91。结论冠心病猝死者心肌FN免疫组化检测可为死因诊断提供可靠依据。     

Coronary arteritis diagnosed at autopsy: three case reports and review of the literature

Coronary arteritis is rare but can be fatal either by itself or in conjunction with other diseases. The authors report cases of three men in whom coronary arteritis was an interesting finding that may have caused or contributed to death. One 45-year-old man collapsed at work, another 56-year-old man was found dead in his parked car, and one 80-year-old man had a recent cerebrovascular accident. All three men had coronary arteritis, arteriosclerotic cardiovascular disease, some form of myocardial disease, and fatty liver change. Two had different lung diseases. The findings suggest that coronary arteritis may be an independent cause of death, part of a systemic disease, or, as these three cases illustrate, part of a constellation of cardiac and cardiovascular pathologies with a possible relation to other medical conditions. Coronary arteritis is an important finding in forensic pathology and merits consideration in a case of unexplained death.     

Immunocytochemical diagnosis of early myocardial ischaemic/hypoxic damage

The sensitive and reliable dinitrophenyl (DNP) hapten sandwich staining (DHSS) procedure (B. Jasani et al., Virchows Arch (Pathol. Anat.), 406 (1985) 441-448) was used to study the distribution of immunoperoxidase staining seen with antibodies to seven protein markers in post-mortem heart tissue. This was obtained from 12 cases with macroscopic myocardial infarction and 17 cases without myocardial infarction (10 with and 7 without significant coronary artery atherosclerosis). The immunostaining patterns were compared with the appearances seen in adjacent sections stained by the routine haematoxylin and eosin (H & E) and phosphotungstic acid haematoxylin (PTAH) methods and a method previously recommended for the detection of early myocardial infarction, the haematoxylin basic fuchsin picric acid (HBFP) stain. Loss of immunostaining with an antibody to myoglobin was found to be a reliable and more objective marker of both early and established myocardial infarction compared with the histological stains. Antibodies to myosin, caeruloplasmin, C-reactive protein and pre-albumin gave similar but less reliable results, whilst those to complement factor C3b and alpha-1 anti-trypsin gave the least reliable results for early myocardial ischaemic/hypoxic damage. The immunocytochemical results are considered sufficiently encouraging to extend the work to a large number of sudden death cases in order to establish a new, more reliable approach to the detection of histologically latent ischaemic/hypoxic damage in the myocardium.