Lesions of the Cardiac Conduction System and Sudden Death.

ABSTRACT: When a young previously healthy person dies suddenly, occasionally, the scene is noncontributory and the autopsy and drug screen are negative. In such cases, additional studies, including genetic assessment and cardiac conduction system examination, should be performed. We performed a literature search and reviewed our own material to identify possible or definite conduction system anomalies that may cause death. We identified intrinsic conduction system disease including cystic tumor of the atrioventricular node, atrioventricular node (cystic tumor of the AV node), and fibromuscular dysplasia of the atrioventricular node artery to be likely causes of death. Extrinsic causes, in which a generalized disease affects the conduction system, include tumors, autoimmune disease, infiltrative disorders, and others, are a second category of diseases that can affect the conduction system and cause atrioventricular block and sudden death.

Sudden cardiac death in the young: A consensus statement on recommended practices for cardiac examination by pathologists from the Society for Cardiovascular Pathology.

Sudden cardiac death is, by definition, an unexpected, untimely death caused by a cardiac condition in a person with known or unknown heart disease. This major international public health problem accounts for approximately 15-20% of all deaths. Typically more common in older adults with acquired heart disease, SCD also can occur in the young where the cause is more likely to be a genetically transmitted process. As these inherited disease processes can affect multiple family members, it is critical that these deaths are appropriately and thoroughly investigated. Across the United States, SCD cases in those less than 40 years of age will often fall under medical examiner/coroner jurisdiction resulting in scene investigation, review of available medical records and a complete autopsy including toxicological and histological studies. To date, there have not been consistent or uniform guidelines for cardiac examination in these cases. In addition, many medical examiner/coroner offices are understaffed and/or underfunded, both of which may hamper specialized examinations or studies (e.g., molecular testing). Use of such guidelines by pathologists in cases of SCD in decedents aged 1-39 years of age could result in life-saving medical intervention for other family members. These recommendations also may provide support for underfunded offices to argue for the significance of this specialized testing. As cardiac examinations in the setting of SCD in the young fall under ME/C jurisdiction, this consensus paper has been developed with members of the Society of Cardiovascular Pathology working with cardiovascular pathology-trained, practicing forensic pathologists.

Fatal visceral larva migrans from Toxocara catis infection of the heart and liver in a child.

We discuss the pathophysiology and epidemiology of Toxocara catis infection complicated by visceral larval migrans . We describe a previously healthy 19-month-old white male child found dead in bed by his mother. He had what was thought to be an upper respiratory infection for several days.The child had eosinophilic hepatitis and myocarditis complicating visceral larval migrans due to Toxocara catis infection from the family cat. We discuss the pathologic and clinical aspects of visceral larval migrans due to of Toxocara catis infection.

Unusual soot pattern from suicidal handgun wound.

Soot is deposited from 20-30 cm from the muzzle of most handguns and arranged concentrically around the entry wound. We examined a case of a self-inflicted gunshot wound from a 9-mm pistol that left an unusual pattern of soot deposition consisting of two circular 3-mm deposits of soot located 2 cm from the entry wound. Examination of the weapon and test-firing it against a cloth reproduced the soot deposits, which were caused by two ports on the top of the barrel. Examination of the weapon and comparing the barrel with the entry wound and surrounding skin may provide important information about the type of weapon, the muzzle-to-target distance, and atypical soot deposits.

Recurrent Cardiogenic Syncope From Extrinsic Organ Anomaly.

CASE PRESENTATION: A 40-year-old woman presented with recurrent syncope. She reported multiple (>20) episodes of non-prodromal loss of consciousness, periodically provoked by physical exertion. One episode resulted in a nasal fracture due to the abrupt nature of her syncope. The characterization of each episode was inconsistent with a neurogenic seizure. Other causes of syncope (vasovagal, situational, carotid hypersensitivity, and orthostasis) were also deemed unlikely. On physical examination, a low-pitched, brief adventitious sound was appreciated after each S2 sound in the right lower sternal border. The remainder of the physical examination was unremarkable. Initial workup, including complete blood count, comprehensive metabolic panel, cardiac enzymes, and ECG yielded normal results. The chest radiograph did not show any gross cardiac or pulmonary parenchymal pathologic condition (Fig 1). Telemetry did not demonstrate any malignant arrhythmias, and video-guided EEG did not document any seizure activity.

Cystic tumour of the atrioventricular node: case report and literature review.

Cystic tumour of the atrioventricular node is the smallest tumour that can cause sudden cardiac death. This lesion arises from foregut endodermal rests which become enfolded into the heart during embryogenesis. Typically causing heart block, the tumour can cause sudden death despite pacemaker placement. Sudden death in such cases can be caused by arrhythmogenic ectopic foci arising from impaired electrical impulse propagation through the abnormal atrioventricular junction conducting tissue.

Fatal Intestinal Obstruction in a Patient With Fetal Alcohol Syndrome.

We describe an 8-year-old white boy with a history of fetal alcohol syndrome and pica, who was found dead on the floor by his mother. The child died from massive intestinal dilatation causing asphyxia. We discuss the potential pathogenetic mechanisms of intestinal dilation in patients with fetal alcohol syndrome.

The danger zone: Injuries and conditions associated with immediately fatal motorcycle crashes in the state of Michigan.

BACKGROUND: Immediately fatal motorcycle crashes have not been well characterized. This study catalogues injuries sustained in fatal motorcycle crashes and assesses the impact of crash conditions on injury patterns. METHODS: Autopsy records from the office of the medical examiner of Kent County, MI and publicly available traffic reports were queried for information pertaining to motorcyclists declared dead on-scene between January 1, 2007, and December 31, 2016. RESULTS: A total of 71 autopsies of on-scene motorcycle crash fatalities were identified. The two most prevalent injuries were traumatic brain injury (TBI) (85%) and rib fractures (79%). The majority of fatalities occurred in daylight hours (54.3%) and in a 55 mph speed limit zone (63.8%). CONCLUSIONS: This study provides a catalogue of the injuries sustained in immediately fatal motorcycle crashes and the associated conditions. Advocacy efforts that highlight the risks associated with motorcycle riding and that promote safe riding practices are warranted.

Fatal Airway Obstruction in a Man With a Cystic Hygroma.

We describe a 24-year-old man with a cystic hygroma of the left side of the lower neck that led to sudden death. Cystic hygroma (cystic lymphangioma) is a congenital malformation of the lymphatic system. The patient, who had a tracheostomy because of airway obstruction from the cystic hygroma, was found dead with his tracheostomy tube on the floor next to him. Complications of cystic hygroma include infiltration of the neck causing airway obstruction, dysphagia, pain, and obstructive sleep apnea.

A case of sudden cardiac death due to eosinophilic coronary periarteritis: possible significance of coexisting atherosclerosis and eosinophilic inflammation of the esophagus.

BACKGROUND: Eosinophilic coronary periarteritis (ECPA) is a rare disease found in cases of sudden cardiac death due to coronary vasospasm or spontaneous coronary artery dissection. Currently, the etiology, pathogenesis, and pathophysiology of ECPA are unknown. Cases of ECPA with a history of allergic disorders are rare. Only one case of ECPA with tissue eosinophilia in another organ has been reported. METHODS: A 50-year-old male suddenly died after complaining of chest pain. An autopsy with histopathologic analysis was performed. RESULTS: A short segment of the left anterior descending artery had ECPA with dense eosinophilic inflammation of the adventitia and mild atherosclerosis. There were findings atypical of ECPA including mild focal eosinophilic infiltration of the intima and media associated with proliferation of vasa vasorum, fragmented internal and external elastic laminae, and fibrosis of the media. In addition, eosinophilic inflammation of the esophagus without mucosal involvement was present. The eosinophilic inflammation of the coronary artery and esophagus was accompanied by an increased number of mast cells. CONCLUSIONS: This case suggests that ECPA and atherosclerosis may act synergistically by induction of inflammation and vasa vasorum neovascularization. Vasa vasorum and mast cell infiltration may trigger vasospasm and spontaneous coronary artery dissection. Although concurrent tissue eosinophilia elsewhere is rarely observed in cases of ECPA, collective analysis of these cases may elucidate the etiology and pathophysiology of ECPA.

Primary Cardiac Fibroma in an Adult.

Cardiac fibromas are benign primary tumors composed of connective tissue and fibroblasts. These uncommon tumors are primarily found in the pediatric population, and their prevalence among the adult population is exceedingly rare. We report a case of an adult with nonspecific symptoms, who was subsequently found to have a solitary mass located in the left ventricle. This case highlights an unusual finding in an adult who through various imaging modalities, surgical excision, and immunohistological analysis was found to have a cardiac fibroma.

Self-administered ethanol enema causing accidental death.

Excessive ethanol consumption is a leading preventable cause of death in the United States. Much of the harm from ethanol comes from those who engage in excessive or hazardous drinking. Rectal absorption of ethanol bypasses the first pass metabolic effect, allowing for a higher concentration of blood ethanol to occur for a given volume of solution and, consequently, greater potential for central nervous system depression. However, accidental death is extremely rare with rectal administration. This case report describes an individual with klismaphilia whose death resulted from acute ethanol intoxication by rectal absorption of a wine enema.

Fatal coronary artery intimal hyperplasia due to amphetamine use.

BACKGROUND: Amphetamines have been reported to cause myocardial infarct, cerebral hemorrhage, aortic dissection, hypertension, vasculitis, aneurysms, and, occasionally, death from direct toxicity. To date, there have been no reports of coronary intimal hyperplasia in an amphetamine user. METHODS: A 29-year-old male was found collapsed after jogging. He had been taking amphetamines for 11 years for attention deficit/hyperactivity disorder. Past medical history was positive for mild hypertension and migraine headaches. He underwent a complete autopsy and drug screen. RESULTS: At gross autopsy his left anterior descending (LAD) coronary artery was occluded and he had an old myocardial infarct in the anterior wall of the left ventricle. Microscopic findings included occlusive intimal hyperplasia (positive for smooth muscle actin) in the LAD and an old left ventricular anterior wall infarct surrounded by acute infarct. CONCLUSION: In addition to other reported adverse effects, amphetamines can also cause occlusive intimal hyperplasia of the coronary arteries.

Circumflex artery from the right coronary sinus: a not-so-benign anomaly.

The origin of the circumflex coronary artery from the right sinus of Valsalva is generally considered a benign anomaly. Herein we report the sudden unexpected death of a 6-year-old boy who died after jumping into a swimming pool and whose only pathologic finding was this usually inconsequential coronary artery anomaly. A discussion of the pathophysiology of the disorder and a literature review are included. This is the youngest patient to die with this entity.

Incidence of pulmonary fat embolism at autopsy: an undiagnosed epidemic.

BACKGROUND: To determine the incidence, time course, and severity of pulmonary fat embolism (PFE) and cerebral fat embolism (CFE) in trauma and nontrauma patients at the time of autopsy. METHODS: Prospectively, consecutive patients presenting for autopsy were evaluated for evidence pulmonary and brain fat embolism. The lung sections were obtained from the upper and lower lobe of the patients' lungs on the right and left and brain tissue. This tissue was prepared with osmium tetroxide for histologic evaluation. The number of fat droplets per high power field was counted for all sections. The autopsy reports and medical records were used to determine cause of death, time to death, injuries, if cardiopulmonary resuscitation (CPR) was attempted, sex, height, weight, and age. RESULTS: Fifty decedents were evaluated for PFE and CFE. The average age was 45.8 years ± 17.4 years, average body mass index was 30.1 kg/cm² ± 7.0 kg/cm², and 68% of the patients were men. The cause of death was determined to be trauma in 68% (34/50) of decedents, with 88% (30/34) blunt and 12% (4/34) penetrating. CPR was performed on 30% (15/50), and PFE was present in 76% (38/50) of all patients. Subjects with PFE had no difference with respect to sex, trauma, mechanism of injury, CPR, external contusions, fractures, head, spine, chest, abdominal, pelvic, and extremity injuries. However, subjects without PFE had significantly increased weight (109 ± 29 kg vs. 86 ± 18 kg; p = 0.023) but no difference in height or body mass index. PFE was present in 82% (28/34) of trauma patents and 63% (10/16) nontrauma patients. Eighty-eight percent of nontrauma patients and 86% of trauma patients who received CPR had PFE. Trauma patients with PFE showed no significant difference in any group. Eighty-eight percent of trauma patients died within 1 hour of injury, and 80% (24/30) of them had PFE at the time of autopsy. CFE was present only in one patient with a severe head and cervical spine injury. CONCLUSION: PFE is common in trauma patients. CPR is associated with a high incidence of PFE regardless of cause of death. PFE occurs acutely within the "golden hour" and should be considered in traumatically injured patients. Further studies are needed to evaluate the pathogenesis of PFE.

Cerebral fat embolism without intracardiac shunt: A novel presentation.

Fat embolism syndrome (FES) is defined as an uncommon life-threatening disease process consisting of pulmonary, central nervous system (CNS), and cutaneous manifestations. The pathophysiology of this secondary injury is poorly understood. In the setting of the multiply injured patient, the diagnosis of FES is difficult to ascertain. A case report of a posttraumatic death caused by acute dissemination of diffuse fat emboli to the brain and lungs in the absence of a right-to-left heart defect after femur fracture is presented. The transesophageal echo cardiogram with bubble study failed to demonstrate an intracardiac defect or AV malformation in the lung further supporting a biochemical process. The acute decompensation of the patient within 2 h of the injury would favor mechanical emboli. Supportive care continues to be the mainstay of treatment for FES. Cerebral fat embolism should be considered in traumatically injured patients with unexplained decline in their neurologic examination. Cerebral fat embolism may occur without an intracardiac shunt.

Early catastrophic stentless valve failure secondary to possible immune reaction.

Aortic valve replacement with stentless xenografts has become routine since their introduction in the early 1990s. Although concerns of structural valve deterioration and long-term durability have been voiced, the reports on the causes or pathology associated with early valve failure have been sparse. We report two unusual cases of failure leading to patient death within the first year after implantation of the aortic valve and root with the Freestyle prostheses (Medtronic Inc, Minneapolis, MN). We suggest an early immunologic reaction to the xenograft, leading to a fatal inflammatory process, as a mechanism for unusual early valve failure in these patients.