Myocardial contraction bands. Definition, quantification and significance in forensic pathology

A case of lacosamide and mirtazapine self-poisoning

Lacosamide is a relatively new antiepileptic drug that exerts its anticonvulsant effect by selectively inactivating sodium channels. Since its launch, it has been used widely for the treatment of intractable epilepsy, but there are scant data on the toxic or lethal blood concentrations. Here, we report a case of drug poisoning following simultaneous high-dose self-administration of lacosamide and mirtazapine. We developed and validated an approach that uses liquid chromatography coupled with electrospray ionization-tandem mass spectrometry to determine the concentrations of lacosamide and mirtazapine in cadaveric blood, urine and liver. Calibration curves showed good linearity (r2 > 0.995), and our method enabled repeatable and accurate quantification, with intra- and inter-assay coefficients of variation not exceeding 10.9 % and 12.8 %, respectively, for each target drug. We used the method to measure the drug concentrations in the blood of a dead victim and found a lacosamide concentration of 91.9 μg/mL and a mirtazapine concentration of 12.0 μg/mL. The blood mirtazapine concentration was in the lethal range, and that of lacosamide was about 10 times the therapeutic range. The synergistically central nervous system depressive and cardiotoxic effects of these drugs may have contributed to the cause of death. We concluded that the cause of death in this case was lacosamide and mirtazapine poisoning.

Sudden Cardiac Death and Ex-Situ Post-Mortem Cardiac Magnetic Resonance Imaging: A Morphological Study Based on Diagnostic Correlation Methodology

During the last years, post-mortem imaging has gradually been assumed within research in the field of forensic pathology. This role appears to be clearly and simply applied in the trauma field with the use of conventional radiography or Post Mortem Computed Tomography (PMCT). Recently, particular attention was paid to cardiovascular imaging using Post Mortem Magnetic Resonance Imaging (PMMRI). The present experimental study aims to: (i) confirm the efficacy of a Post Mortem Cardiac Resonance Imaging (PMCRI) study protocol for the study of human hearts collected during the autopsy; (ii) apply the defined protocol on subjects who died of “SCD (sudden cardiac death)”, to identify alterations that could guide subsequent sampling. Two hearts of healthy subjects (A: male 22 years; B: female 26 years), who died from causes other than SCD were collected and compared to hearts that belonged to SCD individuals (C: male, 47 years old; D: female, 44 years old; E: male; 72 years old). The exams were performed on a 1.5 T scanner (Philips Intera Achieva, Best, the Netherlands) on hearts collected during autopsy and after a 30-day formalin fixation. Two readers analyzed the obtained images blindly and after randomization. From the comparison between the data from imaging and the macroscopic and histological investigations carried out, the present study proved the effectiveness of a PMMRI protocol to study ex-situ hearts. Moreover, it suggested the following semeiology in post-mortem SCD cases: the hyperintense area with indistinct margins in the Short Tau Inversion Recovery (STIR) sequence was linked to edema or area of pathological fibers, whereas the hypointense area in the T2-FFE sequences was linked to fibrosis. PMMRI can provide a valuable benefit to post-mortem investigations, helping to distinctly improve the success rate of histological sampling and investigations, which remains the gold standard in the diagnosis of sudden death.

Forensic significance of intracardiac heme oxygenase-1 expression in acute myocardial ischemia

Heme oxygenase-1 (HO-1), an inducible stress-response protein, exerts anti-oxidant and anti-apoptotic effects. However, its significance in forensic diagnosis of acute ischemic heart diseases (AIHD) such as myocardial infarction (MI) is still unknown. We examined the immunohistochemical expression of HO-1 in the heart samples to discuss their forensic significance to determine acute cardiac ischemia. The heart samples were obtained from 23 AIHD cases and 33 non-AIHD cases as controls. HO-1 positive signals in cardiomyocyte nuclear were detected in 78.2% of AIHD cases, however, that were detected in only 24.2% control cases with statistical difference between AIHD and non-AIHD groups. In contrast to HO-1 protein expression, there was no significant difference in the appearance of myoglobin pallor regions and leukocyte infiltration in the hearts between AIHD and non-AIHD groups. From the viewpoints of forensic pathology, intracardiac HO-1 expression would be considered a valuable marker to diagnose AIHD as the cause of death.

Myocarditis-induced Sudden Death after BNT162b2 mRNA COVID-19 Vaccination in Korea: Case Report Focusing on Histopathological Findings

We present autopsy findings of a 22-year-old man who developed chest pain 5 days after the first dose of the BNT162b2 mRNA vaccine and died 7 hours later. Histological examination of the heart revealed isolated atrial myocarditis, with neutrophil and histiocyte predominance. Immunohistochemical C4d staining revealed scattered single-cell necrosis of myocytes which was not accompanied by inflammatory infiltrates. Extensive contraction band necrosis was observed in the atria and ventricles. There was no evidence of microthrombosis or infection in the heart and other organs. The primary cause of death was determined to be myocarditis, causally-associated with the BNT162b2 vaccine.

Cardiac sudden death in a young cannabis user

We report a case of sudden death due to acute coronary syndrome (ACS) in a young cannabis user. A man in his late thirties died at home, and marijuana was found. The autopsy revealed severe occlusion by an atherosclerotic plaque in the left anterior descending artery. The histopathological examination revealed ischemic changes, likely caused by cannabis-induced sympathetic β-adrenergic stimulation. Both cannabinoid receptors (CB1 and CB2) were expressed in the atherosclerotic lesions. The CB2 expression was higher than CB1 expression in the atherosclerotic plaque, corresponding to macrophage infiltration. Since cannabis is regarded as a casual drug due to its lower levels of dependency, some individuals have supported legalized marijuana use. However, this case report will provide cautions on the casual use of cannabis.

Dystrophin and metalloproteinase 9 in myocardial ischemia: A post-mortem immunohistochemical study

The presented study evaluated the expression of dystrophin and MMP-9 in cases of sudden cardiac death (SCD) due to coronary atherosclerotic disease (CAD) in order to analyze the characteristics and the chronology of their expression, providing evidence on the possible role in post-mortem diagnosis of myocardial ischemia. The expression of these proteins was also compared to C5b-9 complex and fibronectin expression to evaluate any differences. Two groups of CAD-related SCD, respectively group 1 with gross and/or histological evidence and group 2 with no specific histological signs of myocardial ischemia, were used. A third group formed by cases of acute mechanical asphyxiation was used as a control. The immunohistochemical staining by dystrophin, MMP-9, C5b-9, and fibronectin antibodies was performed. The study revealed that dystrophin and MMP-9 showed different expression in group 1 and group 2 as, respectively, different degree of sarcolemmal staining depletion and increasing of interstitial and granulocytes immunopositivity. Moreover, loss of dystrophin staining and C5b-9 immunopositivity were more significant when compared to MMP-9 increasing. Dystrophin and MMP-9 seemed to be useful immunohistochemical markers for the detection of myocardial ischemic damage. However, the comparison of the four markers suggested that loss of dystrophin could be considered as an earlier marker.

Sudden cardiac death-update

Sudden cardiac death (SCD) is one of the most common causes of death worldwide with a higher frequency especially in the young. Therefore, SCD is represented frequently in forensic autopsy practice, whereupon pathological findings in the heart can explain acute death. These pathological changes may not only include myocardial infarction, coronary thrombosis, or all forms of myocarditis/endocarditis but also rare diseases such as hereditary structural or arrythmogenic anomalies, lesions of the cardiac conduction system, or primary cardiac tumours.

Cardiomyocyte Injury Following Acute Ischemic Stroke: Protocol for a Prospective Observational Cohort Study

Background

Elevated cardiac troponin, which indicates cardiomyocyte injury, is common after acute ischemic stroke and is associated with poor functional outcome. Myocardial injury is part of a broad spectrum of cardiac complications that may occur after acute ischemic stroke. Previous studies have shown that in most patients, the underlying mechanism of stroke-associated myocardial injury may not be a concomitant acute coronary syndrome. Evidence from animal research and clinical and neuroimaging studies suggest that functional and structural alterations in the central autonomic network leading to stress-mediated neurocardiogenic injury may be a key underlying mechanism (ie, stroke-heart syndrome). However, the exact pathophysiological cascade remains unclear, and the diagnostic and therapeutic implications are unknown.

Objective

The aim of this CORONA-IS (Cardiomyocyte injury following Acute Ischemic Stroke) study is to quantify autonomic dysfunction and to decipher downstream cardiac mechanisms leading to myocardial injury after acute ischemic stroke.

Methods

In this prospective, observational, single-center cohort study, 300 patients with acute ischemic stroke, confirmed via cerebral magnetic resonance imaging (MRI) and presenting within 48 hours of symptom onset, will be recruited during in-hospital stay. On the basis of high-sensitivity cardiac troponin levels and corresponding to the fourth universal definition of myocardial infarction, 3 groups are defined (ie, no myocardial injury [no cardiac troponin elevation], chronic myocardial injury [stable elevation], and acute myocardial injury [dynamic rise/fall pattern]). Each group will include approximately 100 patients. Study patients will receive routine diagnostic care. In addition, they will receive 3 Tesla cardiovascular MRI and transthoracic echocardiography within 5 days of symptom onset to provide myocardial tissue characterization and assess cardiac function, 20-min high-resolution electrocardiogram for analysis of cardiac autonomic function, and extensive biobanking. A follow-up for cardiovascular events will be conducted 3 and 12 months after inclusion.

Results

After a 4-month pilot phase, recruitment began in April 2019. We estimate a recruitment period of approximately 3 years to include 300 patients with a complete cardiovascular MRI protocol.

Conclusions

Stroke-associated myocardial injury is a common and relevant complication. Our study has the potential to provide a better mechanistic understanding of heart and brain interactions in the setting of acute stroke. Thus, it is essential to develop algorithms for recognizing patients at risk and to refine diagnostic and therapeutic procedures.

Trial Registration

Clinicaltrials.gov NCT03892226; https://www.clinicaltrials.gov/ct2/show/NCT03892226.

International Registered Report Identifier (IRRID)

DERR1-10.2196/24186

Neurological update: use of cardiac troponin in patients with stroke

Cardiac troponin is a specific and sensitive biomarker to identify and quantify myocardial injury. Myocardial injury is frequently detected after acute ischemic stroke and strongly associated with unfavorable outcomes. Concomitant acute coronary syndrome is only one of several possible differential diagnoses that may cause elevation of cardiac troponin after stroke. As a result, there are uncertainties regarding the correct interpretation and optimal management of stroke patients with myocardial injury in clinical practice. Elevation of cardiac troponin may occur as part of a 'Stroke-Heart Syndrome'. The term 'Stroke-Heart Syndrome' subsumes a clinical spectrum of cardiac complications after stroke including cardiac injury, dysfunction, and arrhythmia which may relate to disturbances of autonomic function and the brain-heart axis. In this review, we provide an up-to-date overview about prognostic implications, mechanisms, and management of elevated cardiac troponin levels in patients with acute ischemic stroke.

Membrane Attack Complex in Myocardial Ischemia/Reperfusion Injury: A Systematic Review for Post Mortem Applications

The complement system has a significant role in myocardial ischemia/reperfusion injury, being responsible for cell lysis and amplification of inflammatory response. In this context, several studies highlight that terminal complement complex C5b-9, also known as the membrane attack complex (MAC), is a significant contributor. The MAC functions were studied by many researchers analyzing the characteristics of its activation in myocardial infarction. Here, a systematic literature review was reported to evaluate the principal features, advantages, and limits (regarding the application) of complement components and MAC in post mortem settings to perform the diagnosis of myocardial ischemia/infarction. The review was performed according to specific inclusion and exclusion criteria, and a total of 26 studies were identified. Several methods studied MAC, and each study contributes to defining better how and when it affects the myocardial damage in ischemic/reperfusion injury. The articles were discussed, focusing on the specificity, sensibility, and post mortem stability of MAC as a marker of myocardial ischemia/infarction, supporting the usefulness in routine post mortem investigations.

Massive β1-Adrenergic Receptor Reaction Explains Irreversible Acute Arrhythmia in a Fatal Case of Acute Pure Caffeine Intoxication

Caffeine, a naturally occurring purine-based alkaloid, is the most consumed psychostimulant worldwide. Since caffeine pharmacokinetics shows extreme interindividual variability, it is not easy to establish its toxic dose. Only a few cases of death due to acute caffeine intoxication have been described so far, the majority of which attributable to massive assumption of caffeine-based medications. We present a case of acute caffeine overdose due to ingestion of pure caffeine. The extremely high blood concentration of caffeine determined a strong cardiovascular response, leading to fatal arrhythmia, as supported by histological evidence of myocardial injury. Quantitation of catecholamines and their metabolites in urine samples was performed and showed level near the highest limit of normal ranges for norepinephrine and high level of epinephrine. Contraction band is a pathological modification of the myocell caused by the catecholaminergic action and can occur in conditions of alteration due to the interaction between calcium and catecholamines. We demonstrated the β1-adrenoceptor involvement in our fatal case by immunohistochemical analysis.

Cardiovascular Manifestations and Complications of Pheochromocytomas and Paragangliomas

Pheochromocytomas and paragangliomas (PPGLs) are rare neuro-endocrine tumors. The catecholamine surge causes paroxysmal or chronic secondary hypertension. PPGLs may present as hypertensive- or PPGL-crisis with severe life-threatening cardiac and cerebrovascular complications. PPGLs-induced cardiac manifestations have been reported with diagnoses as PPGLs-induced electrocardiogram (ECG) changes “mimicking acute myocardial infarction”, arrhythmias, myocarditis, acute coronary syndrome, dilated cardiomyopathy, and lately as takotsubo syndrome. Critical analysis of these reports reveals that most of these cardiac manifestations have certain features in common. They have a dramatic clinical presentation and are reversible if the disease is treated with appropriate medical therapy and surgical resection of the PPGL tumor. They may have the same repolarization ECG changes irrespective of the clinical cardiac diagnosis, usually associated with mild to moderate elevations of myocardial biomarkers as troponins and normal coronary arteries. The histopathological findings are usually focal or multifocal in the form hypercontracted sarcomeres and contraction band necrosis (myofibrillar degeneration) with subsequent secondary mononuclear cell infiltration. Evidences argue the PPGL caused surge of catecholamines triggers hyperactivation of the sympathetic nervous system with cardiac sympathetic nerve terminal disruption with norepinephrine spillover causing the cardiac complications. A comprehensive review of various reported cardiovascular manifestations and complications of PPGLs are presented.

Fatal α-PVP and amphetamine poisoning during a sauna and autoerotic practices

We describe the sudden death of a middle-aged man while having a sauna under the influence of α-pyrrolidinovalerophenone (α-PVP) (PM blood concentration: 0.8 mg/L), amphetamine (0.34 mg/L), and other drugs (buprenorphine, benzodiazepines), and engaging in solitary sexual activities. The drugs’ effects on the cardio-circulatory system and on body thermoregulation combined with the high temperatures are likely to have been central mechanisms leading to death. The high levels of adrenaline triggered by sexual arousal and the respiratory depression caused by buprenorphine, in association with benzodiazepines, may have also contributed to his death. This previously unreported type of accidental autoerotic death illustrates the risk of using amphetamine-like sympathomimetic drugs (e.g. cathinone derivates) in hot environments such as a sauna, and during sexual activities therein.

The congenital disorder of glycosylation in PGM1 (PGM1-CDG) can cause severe cardiomyopathy and unexpected sudden cardiac death in childhood

INTRODUCTION

Sudden cardiac death (SCD) in the young is rare and should always lead to suspicion of a genetic cardiac disorder. We describe a family, in which the proband was a girl deceased by sudden cardiac death in the playground at thirteen years of age. The index-patient had short stature, cleft palate but no previous cardiac symptoms. We found an uncommon cause of cardiomyopathy, due to a congenital disorder of glycosylation (CDG), previously described to cause a variable range of usually mild symptoms, and not previously found to cause SCD as the first symptom of the condition.

METHODS

The index patient underwent postmortem genetic testing/molecular autopsy for genes known to cause SCD, without a detection of causative agent, why two siblings of similar phenotype as the deceased sister underwent clinical-exome genetic sequencing (next generation sequencing). All first-degree relatives underwent clinical examination including cardiac ultrasound, Holter-ECG, exercise stress test and biochemistry panel.

RESULTS

A genetic variant in the gene for phosphoglucomutase 1 (PGM1) was identified in the index patient and her two brothers, all were found to be homozygous for the genetic variant (G230E) NM_002633.2:c.689 G > A in PGM1. This variant has been linked to a congenital disorder of glycosylation (PGM1-CDG), explaining the clinical picture of short stature, cleft palate, liver engagement and cardiomyopathy. During follow-up one of the brothers died unexpectedly after physical exertion during daily life at the age of twelve years. The other brother fainted during similar circumstances at the age of thirteen years. Both parents and three other siblings were found to be heterozygous gene carriers without risk for the disease.

CONCLUSION

Our findings suggest that there is a need of multidisciplinary discussion and genetic testing after unexpected cardiac death in the young. We have to be more flexible in our evaluation of diseases and to consider even uncommon diseases including rare recessive inherited disorders. Our findings also suggest that the autosomal recessive PGM1-CDG might be highly associated with life-threatening cardiomyopathy with arrhythmia or sudden cardiac death as the first symptom presenting from childhood and adolescence.

Analysis on sarcoglycans expression as markers of septic cardiomyopathy in sepsis-related death

The post-mortem assessment of sepsis-related death can be carry out by many methods recently suggested as microbiological and biochemical investigations. In these cases, the cause of death is a multiple organ dysfunction due to a dysregulated inflammatory response occurring after the failure of infection control process. It was highlighted also that the heart can be a target organ in sepsis which determines the so-called septic cardiomyopathy characterized by myocardial depression. Several mechanisms to explain the pathophysiology of septic cardiomyopathy were suggested, but very few studies about the structural alterations of cardiac cells responsible for myocardial depression were carried out. The aim of this study was to evaluate whether sarcoglycans (SG) were involved in septic cardiac damage analyzing their expression in sepsis-related deaths and, particularly, if these proteins can be used as markers of septic myocardial dysfunction. Cases of septic-related death confirmed by clinical and autopsy records were investigated and compared to a control group of traumatic deaths. Indirect immunofluorescence analysis was performed to analyze α-SG, β-SG, δ-SG, ζ-SG, ε-SG, and γ-SG. Decrease of fluorescence staining pattern for all tested sarcoglycans was observed in the septic-related deaths compared to normal fluorescence staining pattern of control group. These results provide new findings about the myocytes structural alterations due to sepsis and suggest that these proteins could be used in forensic assessment of septic cardiomyopathy.

Comprehensive Histological and Immunochemical Forensic Studies in Deaths Occurring in Custody

In-custody deaths have several causes, and these include homicide, suicide, natural death from chronic diseases, and unexplained death possibly related to acute stress, asphyxia, excited delirium, and drug intoxication. In some instances, these deaths are attributed to undefined accidents and natural causes even though there is no obvious natural cause apparent after investigation. Understanding these deaths requires a comprehensive investigation, including documentation of circumstances surrounding the death, review of past medical history, drug and toxicology screens, and a forensic autopsy. These autopsies may not always clearly explain the death and reveal only nonspecific terminal events, such as pulmonary edema or cerebral edema. There are useful histologic and biochemical signatures which identify asphyxia, stress cardiomyopathy, and excited delirium. Identifying these causes of death requires semiquantitative morphologic and biochemical studies. We have reviewed recent Bureau of Justice Statistics on in-custody death, case series, and morphological and biochemical studies relevant to asphyxia, stress cardiomyopathy, and excited delirium and have summarized this information. We suggest that regional centers should manage the investigation of these deaths to provide more comprehensive studies and to enhance the expertise of forensic pathologists who would routinely manage potentially complex and difficult cases.

Stress cardiomyopathy: Is it limited to Takotsubo syndrome? Problems of definition

In 2006, Takotsubo syndrome (TTC) was described as a distinct type of stress-induced cardiomyopathy (stress cardiomyopathy). However, when thinking about Takotsubo cardiomyopathy from the viewpoints of the AHA and ESC classifications, 2 possible problems may arise. The first potential problem is that a forecast of disease outcome is lacking in the ESC classification, whereas the AHA only states that 'outcome is favorable with appropriate medical therapy'. However, based on the literature data, one can make a general conclusion that occurrence of myocardial lesions in TTC (i.e., myocardial fibrosis and contraction-band necrosis) causes the same effects as in other diseases with similar levels of myocardial damage and should not be considered to have a lesser impact on mortality. To summarise, TTC can cause not only severe complications such as pulmonary oedema, cardiogenic shock, and dangerous ventricular arrhythmias, but also damage to the myocardium, which can result in the development of potentially fatal conditions even after the disappearance of LV apical ballooning. The second potential problem arises from the definition of TTC as a stress cardiomyopathy in the AHA classification. In fact, the main factors leading to TTC are stress and microvascular anginas, since, as has been already discussed, coronary spasm can cause myocardium stunning, resulting in persistent apical ballooning. Thus, based on this review, 3 distinct types of stress cardiomyopathies exist (variant angina, microvascular angina, and TTC), with poor prognosis. Adding these diseases to the classification of cardiomyopathies will facilitate diagnosis and preventive prolonged treatment, which should include intensive anti-stress therapy.

A case of sudden death after Japanese encephalitis vaccination

Japanese encephalitis (JE) virus is estimated to result in 3500-50,000 clinical cases every year, with mortality rates of up to 20-50% and a high percentage of neurological sequelae in survivors. Vaccination is the single most important measure in preventing this disease. Inactivated Vero cell culture-derived JE vaccines have not been linked to any fatalities, and few serious adverse events after vaccination have been reported. Here, we report a case of sudden death in which a 10-year-old boy experienced cardiopulmonary arrest 5 min after receiving a Japanese encephalitis vaccination. He had been receiving psychotropic drugs for the treatment of pervasive developmental disorders. Postmortem examinations were nonspecific, and no signs of dermatologic or mucosal lesions or an elevation of the serum tryptase level, which are characteristic of anaphylaxis, were observed. A toxicological examination revealed that the blood concentrations of the orally administered psychotropic drugs were within the therapeutic ranges. The patient was considered to have died of an arrhythmia that was not directly associated with the vaccination.

Histologic pathologies of the myocardium in septic shock: a prospective observational study

Myocardial depression in septic shock is well known, but its pathophysiological genesis is incompletely understood. To assess the incidence and extent of stress-induced histologic myocardial alterations in septic shock, a prospective, observational, combined clinical and postmortem study was conducted, and 20 patients dying from septic shock were included. Exclusion criteria were younger than 18 years, pregnancy, open heart surgery or cardiopulmonary resuscitation, acute neurologic diseases, pheochromocytoma, and forensic autopsy. A systematic macropathologic evaluation was performed. Nine predefined heart sections were histologically screened for myocytolysis, interstitial fibrosis, contraction band necrosis, mononuclear infiltrates, interstitial edema, and tissue hemorrhage. Stress-induced pathologies were found in 90% to 100% of patients in all heart sections (myocytolysis, 100%; interstitial fibrosis, 100%; contraction band necrosis, 95%; mononuclear infiltrates, 90%; interstitial edema, 90%; tissue hemorrhage, 30%). The incidence and extent of contraction band necrosis, mononuclear infiltrates, and myocytolysis did not differ between sexes; patients with or without chronic β-blocker, calcium antagonist, and/or statin premedication; or between the binary use of different catecholamine agents (all comparisons P > 0.05). The maximum epinephrine dose correlated with the overall extent of mononuclear infiltrates (Spearman-Rho, r = 0.704; P = 0.05) and myocytolysis (Spearman-Rho, r = 0.933; P = 0.001). Maximum norepinephrine doses correlated with the extent of mononuclear infiltrates in the left ventricular anterior wall (Spearman-Rho, r = 0.519; P = 0.02). The total duration of catecholamine therapy was correlated with the extent of mononuclear infiltrates in the apex (Spearman-Rho, r = 0.571; P = 0.009) and right atrium (Spearman-Rho, r = 0.535; P = 0.02). In conclusion, our results suggest that histologic lesions potentially indicative of stress-induced cardiotoxicity can be observed in most patients dying from septic shock.

Post-mortem cardiac 3-T magnetic resonance imaging: visualization of sudden cardiac death?

OBJECTIVES

This study aimed to investigate post-mortem magnetic resonance imaging (pmMRI) for the assessment of myocardial infarction and hypointensities on post-mortem T2-weighted images as a possible method for visualizing the myocardial origin of arrhythmic sudden cardiac death.

BACKGROUND

Sudden cardiac death has challenged clinical and forensic pathologists for decades because verification on post-mortem autopsy is not possible. pmMRI as an autopsy-supporting examination technique has been shown to visualize different stages of myocardial infarction.

METHODS

In 136 human forensic corpses, a post-mortem cardiac MR examination was carried out prior to forensic autopsy. Short-axis and horizontal long-axis images were acquired in situ on a 3-T system.

RESULTS

In 76 cases, myocardial findings could be documented and correlated to the autopsy findings. Within these 76 study cases, a total of 124 myocardial lesions were detected on pmMRI (chronic: 25; subacute: 16; acute: 30; and peracute: 53). Chronic, subacute, and acute infarction cases correlated excellently to the myocardial findings on autopsy. Peracute infarctions (age range: minutes to approximately 1 h) were not visible on macroscopic autopsy or histological examination. Peracute infarction areas detected on pmMRI could be verified in targeted histological investigations in 62.3% of cases and could be related to a matching coronary finding in 84.9%. A total of 15.1% of peracute lesions on pmMRI lacked a matching coronary finding but presented with severe myocardial hypertrophy or cocaine intoxication facilitating a cardiac death without verifiable coronary stenosis.

CONCLUSIONS

3-T pmMRI visualizes chronic, subacute, and acute myocardial infarction in situ. In peracute infarction as a possible cause of sudden cardiac death, it demonstrates affected myocardial areas not visible on autopsy. pmMRI should be considered as a feasible post-mortem investigation technique for the deceased patient if no consent for a clinical autopsy is obtained.

[Sudden cardiac death. Selected forensic aspects]

Sudden cardiac death is one of the most common causes of death and a significant number of sudden deaths occurs especially in young people. Sudden cardiac death is also frequently represented in forensic autopsy practice. In such cases pathological findings in the heart can often explain the reason for the acute death. These pathological changes include not only myocardial infarction, coronary thrombosis and all forms of myocarditis/endocarditis but also rare diseases, such as hereditary structural or arrythmogenic anomalies, lesions of the cardiac conduction system or primary cardiac tumors.

Colloid cyst of the third ventricle, hypothalamus, and heart: a dangerous link for sudden death

Colloid cysts are rare congenital, intracranial neoplasms, commonly located in the third ventricle. Colloid cysts are endodermal congenital malformations. The cysts commonly range in size from 1-2 cm in diameter, although large cysts >3 cm in size have been reported. The components of the cyst include an outer fibrous capsule over an inner epithelium. The epithelium is usually a single layer of mucin-producing or ciliated cells. Such cysts contain mucoid and gelatinous material, which is positive for both Periodic acid Schiff (PAS) and mucicarmen staining. Although colloid cysts usually represent histopathologically benign neoplasms, they can result in sudden, unexpected and potentially lethal complications. The mechanism(s) of death is still a controversial subject and several mechanisms have been postulated to explain the sudden onset of severe symptoms and of fatal rapid deterioration in patients with colloid cysts. In this case, macroscopic and histological findings addressed the diagnosis of colloid cyst of the third ventricle with diffuse myocardial injury (coagulative myocytolysis or contraction band necrosis, CBN) and led us to conclude that acute cardiac arrest due to hypothalamus stimulation in the context of colloid cyst of the third ventricle was the cause of death. As the hypothalamic structures which are involved in neuroendocrine and autonomic regulation playing a key role in cardiovascular control are located close to the walls of the third ventricle which is the most frequent anatomical site of colloid cyst, this may suggest that reflex cardiac effects due to the compression of the hypothalamic cardiovascular regulatory centers by the cyst explain the sudden death in patients harboring a colloid cyst when signs of hydrocephalus or brain herniation are lacking.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/4915842848034158.

Stress echocardiography as a gatekeeper to donation in aged marginal donor hearts: anatomic and pathologic correlations of abnormal stress echocardiography results

BACKGROUND

Owing to the shortage of donor hearts, the criteria for acceptance have been considerably expanded. Pharmacologic stress echocardiography is highly accurate in identifying prognostically significant coronary artery disease, but brain death and catecholamine storm in potential heart donors may substantially alter the cardiovascular response to stress. This study assessed correlates of an abnormal resting/stress echocardiography results in potential donors.

METHODS

From April 2005 to December 2007, 18 marginal candidate donors (9 men) aged 58 +/- 5 years were initially enrolled. After legal declaration of brain death, all marginal donors underwent bedside echocardiography, with baseline and (when resting echocardiography was normal) dipyridamole (0.84 mg/kg in 6 min) or dobutamine (up to 40 microg/kg/min) stress echo. Non-eligible hearts (with abnormal rest or stress echo findings) were excluded and underwent cardioautoptic verification.

RESULTS

Resting echocardiography showed wall motion abnormalities in 5 patients (excluded from donation). Stress echocardiography was performed in the remaining 13 (dipyridamole in 11; dobutamine in 2). Results were normal in 7, of which 6 were uneventfully transplanted in marginal recipients. Results were abnormal in 6, and autoptic verification performed showed coronary artery disease in 5, and initial cardiomyopathy in 1.

CONCLUSIONS

Bedside pharmacologic stress echocardiography can safely be performed in candidate heart donors, is able to unmask occult coronary artery disease or cardiomyopathy, and shows potential to extend donor criteria in heart transplantation. Further experience with using marginal donors is needed before exact guidelines can be established.

[Death during police interrogation--case report]

INTRODUCTION

Cases of sudden and unexpected deaths of criminal suspects in presence of police always have special forensic medical approach. Often, such deaths are preceded by a state of extreme psychophysical activity (excitated delirium) of suspects, when they may injure themselves. Police attempts to prevent that can inevitably lead to struggle. Immediately after the struggle ends (but also during a struggle), they abruptly become unresponsive, and develop cardiopulmonary arrest and death. Presence of drugs significantly intensifies the harmful effect of such state and leads to death.

CASE OUTLINE

We present a case of death of a young man brought into custody during police interrogation. Autopsy showed injuries and presence of MDMA, with suspicion that death was preceded by the state of excitated delirium. After thorough analysis of the case (complete autopsy, toxicological screening, microscopic survey of all organs, circumstances of death etc.), our conclusion is that death was related to drug consumption--ectasy. Concentration ofectasy found in kidneys is the minimum concentration possible that could lead to heart malfunction and death.

CONCLUSION

Our opinion is that there are no medical data by which we could determine if, and in what dosage, undesirable effects of ectasy were enhanced by the circumstances of the case.

Correlation between cardiac oxidative stress and myocardial pathology due to acute and chronic norepinephrine administration in rats

Background: To investigate the cardiotoxic role of reactive oxygen species (ROS) and of products derived from catecholamines auto-oxidation, we studied: (1) the response of antioxidant cardiac cellular defence systems to oxidative stress induced by norepinephrine (NE) administration, (2) the effect of NE administration on cardiac β₁-adrenergic receptors by means of receptor binding assay, (3) the cellular morphological alterations related to the biologically cross-talk between the NE administration and cytokines [tumor necrosis factor-alpha (TNF-α), monocyte chemotactic protein-1 (MCP-1), interleukins IL6, IL8, IL10]Methods and Results: A total of 195 male rats was used in the experiment. All animals underwent electrocardiogram (EKG) before being sacrificed. The results obtained show that NE administration influences the antioxidant cellular defence system significantly increasing glutathione peroxidase (GPx) activity, glutathione reductase (GR) and superoxide dismutase (SOD). The oxidized glutathione (GSH/GSSG) ratio significantly decreases and malondialdehyde (MDA) levels increase showing a state of lipoperoxidation of cardiac tissue. We describe a significant apoptotic process randomly sparse in the damaged myocardium and the effect of ROS on the NE-mediated TNF-α, MCP-1, and IL6, IL8, IL10 production. Conclusions: Our results support the hypothesis that catecholamines may induce oxidative damage through reactive intermediates resulting from their auto-oxidation, irrespective of their interaction with adrenergic receptors, thus representing an important factor in the pathogenesis of catecholamines-induced cardiotoxicity. The rise of the cardioinhibitory cytokines may be interpreted as the adaptive response of jeopardized myocardium with respect to the cardiac dysfunction resulting from NE injection.

Diverse morphological lesions and serious arrhythmias with hemodynamic insults occur in the early myocardial contusion due to blunt impact in dogs

To investigate the morphology and hemodynamics of the early myocardial contusion, an animal model of cardiac contusion was established by impact to the precordial region at sternum at velocity of 10.0m/s with a mechanical elastic-cord propelled impactor in 19 dogs. The electrocardiogram and both the left and right intra-ventricular pressures were recorded continuously throughout the experiment. Histological and immunohistochemical examinations of myoglobin, creatine kinase-MB and fibrinogen were conducted. At the moment of impact, abrupt over-pressures within the left and right ventricles occurred with concomitant serious arrhythmias followed by variety of cardiac conduction disorders and depressed left and right ventricular systolic pressures during the observation times. Histologically, lesions of myocardial contusions were identified at subepicardial, myocardial or subendocardial layer as interstitial hemorrhage, disruption or coagulative necrosis as well as contraction band necrosis of the muscle fibers, which might be categorized into the hemorrhagic, necrotized and mixed forms. The three forms of lesions were found to exist independently, or co-existed in a heart. However, severity of the lesions varied greatly with different parts even within a heart. Intravascular thromboses were occasionally discovered post-impact. Immunohistochemically, loss of myoglobin and creatine kinase-MB from cardiac cells, and accumulation of fibrinogen at the cell membranes were detected 5min post-impact. The intracellular accumulation of fibrinogen increased with extension of post-impact intervals. Our results indicate that diverse morphological lesions concomitant with hemodynamic compromise and serious, even fatal arrhythmias occur in the early myocardial contusion, and intravascular thromboses are occasionally produced, suggesting that traumatic myocardial ischemic lesion may be induced due to blunt impact to the precordial region.

Effect of melatonin and atenolol on carbon monoxide cardiotoxicity: an experimental study in rats

The aim of this study was to define the characteristics of heart rates and myocardial changes in rats exposed to carbon monoxide (CO), and the effects of reoxygenation, atenolol (a beta-blocker) and melatonin after sublethal CO intoxication. Widespread use of beta-blockers in cardiology practice and growing literature on the positive effect of melatonin in ischaemia reperfusion lead us to question their effects in case of CO intoxication. Rats were exposed to CO. After sublethal intoxication the rats were reoxygenated with ambient air. Subsequently blood values, electrocardiographic recordings and pathological changes were examined for each groups. Five rats died after CO intoxication in the control group: no myocardial changes were seen in light microscopy. However, myocardium of seven reoxygenated rats presented contraction bands. Seven reoxygenated rats pretreated with atenolol had a higher number of contraction bands of myocardial cells. Seven reoxygenated rats pretreated with melatonin had more contraction bands than reoxygenated rats, and heart rate recordings of these animals revealed a profund and sustained bradycardia. Thus, melatonin and atenolol appear to have some adverse effects in CO intoxication on the myocardial cells.

Sudden cardiac death during anabolic steroid abuse: morphologic and toxicologic findings in two fatal cases of bodybuilders

We report two cases of sudden cardiac death (SCD) involving previously healthy bodybuilders who were chronic androgenic-anabolic steroids users. In both instances, autopsies, histology of the organs, and toxicologic screening were performed. Our findings support an emerging consensus that the effects of vigorous weight training, combined with anabolic steroid use and increased androgen sensitivity, may predispose these young men to myocardial injury and even SCD.

Ultrasound imaging versus morphopathology in cardiovascular diseases. Myocardial cell damage

This review article summarizes the results of histopathological and clinical imaging studies to assess myocardial necrosis in humans. Different histopathological features of myocardial cell necrosis are reviewed. In addition, the present role of echocardiographic techniques in assessing irreversible myocardial damage is briefly summarized.

A systematic study of a myocardial lesion: Colliquative myocytolysis

BACKGROUND

The term "myocytolysis" was first used to define the repair process of contraction band necrosis associated with an acute myocardial infarction. On the other hand, in the latter condition a "myofibrillolysis," presenting edematous myocardial cells not involved by infarct necrosis, and without evidence of repair process was reported. The objective of this study is to establish the frequency, extent and meaning of this myocardial lesion.

MATERIALS AND METHODS

In 12 groups of patients for a total of 432 cases with and without coronary heart disease, "colliquative myocytolysis"--i.e., progressive vacuolization by loss of myofibrils until their total or subtotal disappearance associated with intramyocellular edema in absence of any cellular reaction--was graded in 16 histological slides of the different cardiac regions in each pathological case.

RESULTS

Colliquative myocytolysis (CM) was present in more than 90% with a maximal extent in cases of irreversible congestive heart failure followed by transplanted heart cases (67%) with a survival greater than 1 week. In all other groups, the lesion was absent or minimal.

CONCLUSIONS

No correlation was found between CM and contraction band necrosis, gender, age, heart weight, myocardial fibrosis, coronary artery stenosis, clinical data. Colliquative myocytolysis is a specific histological marker of congestive heart failure, without relation to coronary blood flow, heart weight and myocardial fibrosis. Vacuolization of myocardial cells may be due to other causes (e.g., storage disease, etc.) or may be an artifact. There is no support for the belief that coronary ischemia or myocardial hypoxia is its causes.

Sudden cardiac death in a child affected by Prader-Willi syndrome

A case of sudden cardiac death in a 3-year-old young male affected by Prader-Willi syndrome, clinically diagnosed and confirmed by means of DNA methylation, is presented. The infant suddenly collapsed at home and was taken apparently unconsciousness by his mother to the emergency clinic where he was pronounced dead. A complete postmortem examination was performed and the histological findings led to the definition of cardiac death with a typical picture of contraction band necrosis. Pulmonary hypoxic alterations are frequently reported as the primary cause of death in PWS cases. In this fatal case according to the macroscopic and microscopic findings, the cause of death was most likely cardiac and possibly related to contraction band necrosis linked with ventricular fibrillation and sudden death.

Myocardial disarray: an architectural disorganization linked with adrenergic stress?

BACKGROUND

Myocardial disarray is a structural abnormality found in specific zones of the normal heart. In some conditions, such as hypertrophic cardiomyopathy (HCM), its occurrence represents a pathological process leading to myocardial asynergy. The incidence of "pathological" myocardial disarray in humans is still not known. It has been suggested that a link exists between adrenergic overactivity and myocardial disarray. The aim of the present study is to compare heart findings in conditions with and without chronic sympathetic overtone for evidence of possible linkage in humans.

MATERIALS AND METHODS

A total of 340 hearts were studied. They were divided into seven groups: sudden/unexpected coronary death; sudden/unexpected death in silent Chagas' disease; brain haemorrhage following berry aneurysm rupture; transplanted hearts; congestive heart failure, AIDS and cocaine abuse. Findings in these hearts were compared with anatomic changes in 92 control hearts, where the decedent had died from head trauma, electrocution, or carbon monoxide intoxication. The frequency and presence of myocardial disarray were recorded and correlated to heart weight, extent of myocardial fibrosis, and contraction band necrosis (CBN).

RESULTS

Hearts from patients with conditions that increased sympathetic tone showed an association of myocardial disarray and contraction band necrosis without any relationship to heart weight.

CONCLUSIONS

Myocardial disarray was observed in cardiac areas where it is not found normally. It was associated with adrenergic myocardial stress morphologically expressed by a higher number of foci (p<0.01) and myocells (p<0.001) with CBN versus findings in normal subjects. The condition deserves further study as a possible myocardial asynergic and arrhythmogenic factor especially in sudden/unexpected death.

Usefulness of a latex agglutination assay for FDP D-dimer to demonstrate the presence of postmortem blood

D-dimer, a specific fragment resulting from degradation of cross-linked fibrin, is an essential marker for the diagnosis of disseminated intravascular coagulation (DIC). Rapid assay for D-dimer using monoclonal antibody coated-latex particles might be useful for discriminating between postmortem and antemortem blood in bloodstains. We tried to detect D-dimer in nine postmortem blood samples by the rapid latex agglutination assay and to quantify them automatically using the latex photometric immunoassay system. The results showed that all samples were positive and that their amounts of D-dimer were 335-2,800 microg/ml (the normal blood level, <1 microg/ml; the pathogenic blood level with DIC, 1-100 microg/ml). Next, nine stains made of postmortem blood were examined by the rapid latex agglutination assay. The result showed that only one case (D-dimer 335 microg/ml blood) showed weak positive while the others (D-dimer 600-2,800 microg/ml blood) were positive. The present study indicates that the latex agglutination assay for D-dimer can be useful to demonstrate the presence of postmortem blood.

Mechanical left ventricular unloading prior to reperfusion reduces infarct size in a canine infarction model

We tested the hypothesis that unloading the left ventricle just prior to reperfusion provides infarct size reduction compared with left ventricular (LV) unloading postreperfusion and reperfusion alone. Twenty-four mongrel dogs were subjected to 2 hr of left anterior descending artery occlusion and 4 hr of reperfusion. A transvalvular (TV) left ventricular assist device (LVAD) was inserted just prior to reperfusion and maintained during the rest of the experiment (LV Assist Pre group). In the LV Assist Post group, the TV LVAD was inserted and activated just after reperfusion. A control group was subjected to reperfusion alone with a sham-TV LVAD. At baseline, the hemodynamic data were similar in the three groups. Myocardial infarct size expressed as percentage of area at risk was significantly reduced in the LV Assist Pre group compared to the control group (P = 0.011) and to the LV Assist Post group (P < 0.05). At 4 hr of reperfusion, transmural myocardial blood flow in the ischemic zone was slightly higher in the animals unloaded prior to reperfusion compared to controls and significantly higher than in the LV Assist Post group (P = 0.04). Postreperfusion end-diastolic wall thickness returned to baseline level in the TV LV Assist Pre group compared to both controls and TV LV Assist Post group. In these latter two groups, a significant increase in postreperfusion end-diastolic wall thickness and contraction band necrosis in the central ischemic zone correlated well with the degree of reperfusion injury. LV unloading prior to, but not after, reperfusion reduces the extent of myocardial necrosis in canine hearts subjected to 2 hr of left anterior descending artery occlusion and 4 hr of reperfusion compared to either reperfusion alone or LV unloading after reperfusion.

Radiofrequency perforation and conventional needle percutaneous transseptal left heart access: Pathological features

Perforating radiofrequency (PRF) energy has been used to obtain percutaneous transseptal left heart access. Contrary to ablative radiofrequency (RF), myocardial tissue responses to PRF thermal injury are incompletely defined. In this study, a newly developed RF catheter system for transseptal left atrial entry was compared with conventional needle puncture. Of 15 piglets having transfemoral cardiac catheterization, 12 had transseptal procedures. Needle punctures (NP) and PRF were followed by acute (1 hr; 3 NP, 3 PRF) and chronic necropsy (1 month; 3 NP, 3 PRF). The remaining three piglets had intentional RF aortic perforation through the atrial roof with necropsy at 1 month. Gross and histopathological effects were examined. Acutely, the gross RF lesion was similar to needle puncture. Histologically, the RF lesions had minimal mural thrombus, an inner zone of thermal injury characterized by grayish cytoplasmic staining (elastic trichrome), and a bubbly transformation of the cytoplasm in innermost cardiomyocytes, partial persistence of cross-striations, and an acute inflammatory reaction. The outer extent of the lesion (< 1 mm) was defined by a halo of contraction band necrosis similar to needle puncture. Acute NP injury showed comparable depth and extent of myocyte necrosis (principally contraction bands) with adjacent tissue hemorrhage and edema. At 1 month, a well-developed densely collagenous scar was present in both aortic and transseptal PRF lesions. The extent of acute RF injury is similar to that seen in conventional NP, but the characteristics of tissue insult are different. Both show well-developed healing at 1 month.

Brief episode of STZ-induced hyperglycemia produces cardiac abnormalities in rats fed a diet rich in n-6 PUFA

Diabetic patients are particularly susceptible to cardiomyopathy independent of vascular disease, and recent evidence implicates cell death as a contributing factor. Given its protective role against apoptosis, we hypothesized that dietary n-6 polyunsaturated fatty acid (PUFA) may well decrease the incidence of this mode of cardiac cell death after diabetes. Male Wistar rats were first fed a diet rich in n-6 PUFA [20% (wt/wt) sunflower oil] for 4 wk followed by streptozotocin (STZ, 55 mg/kg) to induce diabetes. After a brief period of hyperglycemia (4 days), hearts were excised for functional, morphological, and biochemical analysis. In diabetic rats, n-6 PUFA decreased caspase-3 activity, crucial for myocardial apoptosis. However, cardiac necrosis, an alternative mode of cell death, increased. In these hearts, a rise in linoleic acid and depleted cardiac glutathione could explain this "switch" to necrotic cell death. Additionally, mitochondrial abnormalities, impaired substrate utilization, and enhanced triglyceride accumulation could have also contributed to a decline in cardiac function in these animals. Our study provides evidence that, in contrast to other models of diabetic cardiomyopathy that exhibit cardiac dysfunction only after chronic hyperglycemia, n-6 PUFA feeding coupled with only 4 days of diabetes precipitated metabolic and contractile abnormalities in the heart. Thus, although promoted as being beneficial, excess n-6 PUFA, with its predisposition to induce obesity, insulin resistance, and ultimately diabetes, could accelerate myocardial abnormalities in diabetic patients.

Predictive value of preoperative transthoracic echocardiography in patients undergoing adrenalectomy for pheochromocytoma

BACKGROUND

Adrenalectomy for pheochromocytoma is a life-threatening procedure. Few echocardiographic assessments have been reported in patients undergoing adrenalectomy for pheochromocytoma.

METHODS

Sixty-three consecutive patients undergoing adrenalectomy for pheochromocytoma underwent routine preoperative M-mode and two-dimensional echocardiography, and Doppler examination. Abnormal echocardiographic findings were defined as left ventricular dilatation or dysfunction (left ventricular percentage fractional shortening < 30%), and/or left ventricular wall motion abnormalities, and/or left ventricular hypertrophy (left ventricular mass index > 110 g m(-2) in women and >134 g m(-2) in men) and/or valvular abnormalities. Physical characteristics, daily urinary metanephrine and normetanephrine excretions, preoperative functional limitation, pre-existing congestive heart failure, type and duration of surgery, and haemodynamic instability in the intra and postoperative periods were compared in patients with normal and abnormal echocardiographic findings.

RESULTS

Twenty-four out of 63 patients were found to have abnormal preoperative echocardiography. There was no difference between patients with normal and abnormal preoperative echocardiography as regards to the investigated criteria, except for pre-existing self-reported functional limitation and chest pain suggesting coronary artery disease.

CONCLUSIONS

The relevance of routine preoperative echocardiographic examination in patients scheduled for adrenalectomy for pheochromocytoma, who have no cardiac symptoms or clinical evidence of cardiac involvement, is questionable.