Sudden aortic death-proposal for a comprehensive diagnostic approach in forensic and in clinical pathology practice

Reviewing hereditary connective tissue disorders: Proposals of harmonic medicolegal assessments

Hereditary connective tissue disorders (HCTDs) are a heterogeneous group of inherited diseases. These disorders show genetic mutations with loss of function of primary components of connective tissue, such as collagen and elastic fibers. There are more than 200 conditions that involve hereditary connective tissue disorders, while the most known are Marfan syndrome, Osteogenesis Imperfecta, and Ehlers-Danlos syndromes. These disorders need continuous updates, multidisciplinary skills, and specific methodologic evaluations sharing many medicolegal issues. Marfan syndrome and Ehlers-Danlos syndromes show a high risk of early sudden death. As a consequence of this, postmortem genetic testing can identify novel genotype-phenotype correlations which help the clinicians to assess personalized cardiovascular screening programs among the ill subjects. Genetic testing is also essential to identify children suffering from Osteogenesis Imperfecta, especially when a physical abuse is clinically suspected. However, this is a well-known clinical problem even though there are still challenges to interpret genetic data and variants of unknown significance due to the current extensive use of new genetic/genomic techniques. Additionally, the more significant applications and complexities of genomic testing raise novel responsibilities on the clinicians, geneticists, and forensic practitioners as well, increasing potential liability and medical malpractice claims. This systematic review provides a detailed overview on how multidisciplinary skills belonging to clinicians, medicolegal consultants, radiologists, and geneticists can cooperate to manage HCTDs from autopsy or clinical findings to genetic testing. Thus, technical aspects need to be addressed to the medicolegal community since there is no consensus works or guidelines which specifically discuss these issues.

A sudden death, an aortic rupture, and an unexpected cause: a report about suspected child abuse

All unexpected deaths of children require an autopsy to determine the cause of death. In cases of aortic rupture, the immediate cause of death is easily identified at autopsy. Although the majority of aortic ruptures are caused by high-energy trauma, other causes should not be missed.We present and discuss the case of a 29-month-old child who died suddenly at home. Her recent medical history and the ecchymotic lesions observed on external examination of the body appeared potentially suspicious of physical abuse. The autopsy concluded that death was due to complete rupture of the abdominal aorta with associated vertebral disjunction. At first glance, the overall forensic picture could suggest a traumatic death. However, careful inspection of the retroperitoneum revealed a discrete atypical mass of infiltrative tissue within the hematoma. Histopathological examinations confirmed tumor proliferation of the soft tissues, triggering vascular and spinal injuries. Other paraneoplastic elements or metastases were ultimately revealed (orbital and subcutaneous). Overall, this was a rare and fatal case of abdominal aortic rupture induced by tumors. Due to the mechanisms and the forces needed to cause vertebral dislocations and aortic rupture, the combination of the two is highly suggestive of child abuse when an accidental traumatic history is absent or inconsistent with the injuries. Nevertheless, this case illustrates the importance of a systematic and rigorous forensic examination, rather than ignoring other possible diagnoses.

Quantitative study of aortic strain injuries originating from traffic accidents

Aortic injuries are the second leading cause of death after head injuries due to traffic accidents, and strain-induced injuries are becoming increasingly prominent. The quantitative study of aortic strain injury allows for a rapid assessment of the degree of aortic injury after an accident and timely diagnosis of the pathology of aortic injury. It is more reliable than diagnosis based on clinical symptoms alone and it is faster than diagnosis based on imaging. Based on the porcine aortic tensile and injury tests, this study obtained the maximum stress threshold of the aorta that can withstand tensile stress and the safe stress threshold under tensile action, which provides a more detailed data reference about aortic injury in the field of internal medicine. Injuries to the aorta under various degrees of traction were analyzed in detail. A comprehensive and quantitative evaluation criterion for aortic strain injury was proposed, which provides a more in-depth reference for the mechanism of aortic strain injury. In addition, combining it with current imaging promises a combination of numbers and shapes for rapid and accurate diagnosis of aortic strain injury.

Thoracic Aortic Aneurysm and Dissection: Review and Recommendations for Evaluation

ABSTRACT

Aortic dissection and rupture (collectively termed "sudden aortic death") are commonly encountered by forensic pathologists, with an estimated incidence at autopsy between 0.6% and 7.7%. Despite this, there is no standard of practice for the evaluation of sudden aortic death at autopsy.Recent studies have shown 20% of patients with thoracic aortic aneurysm or dissection (TAAD) have an identifiable genetic syndrome, and 19% will have an affected first-degree relative. The past 2 decades have seen identification of new culprit genes and syndromes, which can have subtle or nonexistent external phenotypes. A high index of suspicion is warranted to identify possible hereditary TAAD (H-TAAD), allowing family members to obtain screening to avoid catastrophic vascular events. Forensic pathologists need broad knowledge of the spectrum of H-TAAD and awareness of the relative significance of hypertension, pregnancy, substance use, and microscopic changes of aortic architecture.This article reviews the common subtypes of H-TAAD, including Marfan syndrome, vascular Ehlers-Danlos, Loeys-Dietz, and familial thoracic aortic aneurysm and dissection. Recommendations for the evaluation of sudden aortic death at autopsy are presented, including (1) performance of a complete autopsy, (2) documentation of aortic circumference and valve morphology, (3) notifying family of the need for screening, and (4) preservation of a sample for potential genetic testing.

The characteristics of thoracic aortic dissection in autopsy-diagnosed individuals: An autopsy study

Thoracic aortic dissection (TAD) is the most common cause of sudden cardiac death associated with aortic diseases. The age of TAD victims in forensic studies is significantly younger than hospitalized patients with TAD, while only a few studies have been conducted on autopsy-diagnosed TAD deceased. A retrospective study was conducted at the Medicolegal Center of Sun Yat-sen University from 1999 to 2019 to address the characteristics of TAD victims. A total of 200 deceased from spontaneous rupture of TAD were assessed, with 165 (82.5%) males and 175 (87.5%) Stanford type A deceased. Our main results showed that compared with patients with TAD diagnosed during their lifetime, individuals diagnosed with TAD until an autopsy showed an earlier onset (43.80 years old) and less accompanied hypertension (<50%). Sudden death was the initial symptom of 32 decedents. Instead of chest/back pain (40 decedents), abdominal pain (59 decedents) was the most common initial symptom, and 42 decedents presented with no accompanying pain. A higher proportion of abdominal pain and the painless symptom was associated with a higher risk of misdiagnosis. Women showed a more atypical clinical presentation and rapid progression than men. Younger decedents showed more pronounced left heart changes. The present study implicated the TAD individuals diagnosed until an autopsy as a particular entity, indicating the urgent need for further investigation on early diagnosis and pathogenesis of patients with TAD with atypical pain and painless or with younger age to reduce the burden of TAD-related sudden death.

Rupture of the Ascending Aorta Surgical Area Detected Using Isolated Cardiopulmonary Organ Computed Tomography Angiography: An Autopsy Case Report After Cardiac Surgery

ABSTRACT

We report cause of death after cardiac surgery using isolated cardiopulmonary organ computed tomography angiography (CTA) and a conventional autopsy. A 56-year-old man underwent aortic valve replacement and coronary artery bypass graft surgery under extracorporeal circulation. Massive bleeding occurred suddenly, and the patient died 25 days later. An autopsy revealed fibrinous exudate in the mediastinum and tight attachment of the pericardium to the heart; there were also clots and inflammatory exudate in the chest cavity. Separating the organs in the chest cavity was difficult, especially in the surgical area. We extracted the heart and lungs together and performed cardiovascular CTA and image reconstruction. Results showed spillage of the contrast agent from the anterior wall of the ascending aorta, approximately 4.5 cm from the replaced aortic valve. A histological examination confirmed that the site of contrast agent spillage was the sutured area of the ascending aorta, which was infected, necrotic, and had ruptured. Using the CTA approach for isolated cardiopulmonary organ imaging can accurately display the location of an aortic rupture, which further guides organ inspection and tissue sampling, and avoids irreversible damage to key regions. In conclusion, the approach we describe can provide evidence for determining cause of death.

Aortopulmonary fistula in a Warmblood mare associated with an aortic aneurysm and supravalvular aortic stenosis

This case report describes the clinical presentation, the necropsy findings, and genetic results of a 13-year-old Warmblood mare presented with colic and a bilaterally loud, holosystolic murmur. Echocardiographic examination revealed the presence of a thoracic aortic aneurysm, an aortic pseudoaneurysm, a periaortic hematoma (circumferential cuffing by perivascular hemorrhage), and aortopulmonary fistulation. A supravalvular aortic stenosis (SVAS) was visible during echocardiography. Necropsy confirmed that the thoracic aortic aneurysm had ruptured and connected to the pseudoaneurysm, which fistulated into the pulmonary artery. Histologically, the aneurysm wall revealed chronic lesions such as fibrosis, mucin depositions, mineralizations, and elastin fragmentation. The mid abdominal aorta showed lesions suggestive of a systemic elastin arteriopathy. Molecular analysis, however, could not attribute this disease to a variant in the elastin gene, the most common causative gene for SVAS. To the authors' knowledge, this case report describes a case of aortopulmonary fistulation in a Warmblood horse associated with the presence of SVAS and an aortic aneurysm.

A novel splicing mutation in Marfan syndrome

BACKGROUND

Marfan syndrome (MFS) is a connective tissue disease involving multiple organs and systems such as cardiovascular, skeletal, and ocular systems and is also an autosomal dominant inheritance disorder.

METHOD

A 30-year-old woman was rushed into the hospital owing to sudden persistent pain in the abdomen and died suddenly 2 days later. To find the real cause of death, a forensic autopsy was conducted owing to suspected medical malpractice, and the diagnosis of MFS was made in accordance with the 2010 revised Ghent nosology. By sequencing the gene of Marfan, aneurysm, and related disorders, a novel splicing mutation in the fibrillin-1 gene (FBN1) was detected. For the clinical characteristic findings (wrist and thumb sign) of the daughter, we recommend genetic analysis for the family. To better understand the role of the variant in the disease, we also investigated functional validation of this mutation.

RESULTS

According to the autopsy findings, the cause of death was acute cardiac tamponade caused by aortic rupture. DNA sequencing revealed a novel splicing mutation, c.5672-2delA, which was also detected in her daughter (II2). The functional validation of this mutation showed the base deletion at the same site in the PCR products using cDNA as a template. It is suggested that this mutation may cause abnormal spliceosome during transcription and may encode abnormal protein.

CONCLUSION

A novel pathogenic splicing mutation (c.5672-2delA) was confirmed. Present work enriches the profile mutations in FBN1 associated with MFS and stresses the importance of postmortem genetic analysis in such cases.

Second opinion system for sudden cardiac death cases in forensic practice

Sudden cardiac death (SCD) represents a considerable percentage of cardiovascular deaths worldwide. The most frequent pathological substrate of SCD is atherosclerotic coronary artery disease (CAD). The other, less common, pathologies which can cause SCD include cardiomyopathies, congenital diseases (including abnormal anatomy), and arrhythmias such as channelopathies, many of which are genetically determined. Autopsies of SCD victims are generally performed by forensic pathologists. In some cases, a third person responsibility could be invoked. While CAD diagnosis at post-mortem examination is not a major challenge for the forensic pathologist, the other rarer diseases may be. In such instances, referral of the hearts to specialized centers with recognized expertise is recommended, and this is particularly important in cases of SCDs of young people. Moreover, in order to avoid the frequent overdiagnosis of a pathological heart, an expert opinion should be sought for even in the presence of a morphologically normal heart. In cases where retention of the heart is not feasible, it is essential to provide an extensive photographic documentation, with the indication of the sampling sites for histological examination. However, some practical aspects, as the criteria for case selection in routine forensic practice are missing. In this paper, we present the recommendations for heart retention for a second expert opinion and the alternative of documentation and sampling for cases where retention is not possible.

Postmortem imaging findings and cause of death determination compared with autopsy: a systematic review of diagnostic test accuracy and meta-analysis

BACKGROUND

The aim of this study was to evaluate the sensitivity of postmortem computed tomography (PMCT), postmortem magnetic resonance imaging (PMMR) and PMCT angiography (PMCTA) compared with autopsy in cases of adult death investigations.

METHODS

For this systematic review and meta-analysis, Embase, PubMed, Scopus, Web of Science and Medline were searched for eligible studies in October 2016; a follow-up literature search was conducted in March 2018. Studies referring to PMCT, PMCTA and/or PMMR of more than 3 cases with subsequent autopsy were included. Data were extracted from published texts in duplicate. The extracted outcomes were categorized as follows: soft tissue and organ findings, skeletal injuries, haemorrhages, abnormal gas accumulations and causes of death. The summary measure was sensitivity, if 3 or more studies were available. To combine studies, a random effects model was used. Variability and heterogeneity within the meta-analysis was assessed.

RESULTS

Of 1053 studies, 66 were eligible, encompassing a total of 4213 individuals. For soft tissue and organ findings, there was a high pooled sensitivity with PMCTA (0.91, 95% CI 0.81-0.96), without evidence for between-study variability (Cochrane's Q test p = 0.331, I² = 24.5%). The pooled sensitivity of PMCT+PMMR was very high in skeletal injuries (0.97, CI 0.87-0.99), without evidence for variability (p = 0.857, I² = 0.0%). In detecting haemorrhages, the pooled sensitivity for PMCT+PMMR was the highest (0.88, 95% CI 0.35-0.99), with strong evidence of heterogeneity (p < 0.05, I² > 50%). Pooled sensitivity for the correct cause of death was the highest for PMCTA with 0.79 (95% CI 0.52-0.93), again with evidence of heterogeneity (p = 0.062, I² > 50%).

CONCLUSION

Distinct postmortem imaging modalities can achieve high sensitivities for detecting various findings and causes of death. This knowledge should lead to a reasoned use of each modality. Both forensic evidence and in-hospital medical quality would be enhanced.

Sudden Death Due to Thoracic Aortic Dissection in Young People: A Multicenter Forensic Study

INTRODUCTION AND OBJECTIVES

Thoracic aortic dissection (TAD) is infrequent in young people and its characteristics differ from those in the adult population. This study aimed to analyze the clinical and pathological characteristics of sudden death due to TAD in people aged 1 to 35 years.

METHODS

Multicenter population-based study based on forensic autopsies conducted in the provinces of Biscay (1991-2016), Valencia (2000-2016), and Seville (2004-2016).

RESULTS

We identified 35 individuals with sudden death due to TAD (80% males), with a mean age of 29±5 years. The incidence was 0.09/100 000 inhabitants/y. Eighteen persons had at least 1 risk factor for TAD, and this figure increased to 29 when postmortem findings were included: congenital heart disease (n=16), suspicion of familial TAD (n=11), cocaine use (n=6), and hypertension (n=5). Twenty-four individuals, 12 with at least 1 risk factor, had prodromal symptoms, and 16 of them visited their physician, but TAD was not suspected in any of them. The most frequent symptom was chest pain (n=12). The main autopsy findings were cystic degeneration of the media (n=27), dilatation of the ascending aorta (n=21), cardiac hypertrophy (n=20), and bicuspid aortic valve (n=14).

CONCLUSIONS

The incidence of sudden death due to TAD in young people was very low. The most frequent risk factors were congenital heart disease followed by suspicion of familial TAD and cocaine use. TAD should be included in the differential diagnosis of chest pain in young people, mainly male patients with at least 1 risk factor.