Sudden cardiac death in the young: the bogeyman

Associations of MYPN, TTN, SCN5A, MYO6 and ELN Mutations With Arrhythmias and Subsequent Sudden Cardiac Death: A Case Report of an Ecuadorian Individual

Cardiac pathologies are among the most frequent causes of death worldwide. Regarding cardiovascular deaths, it is estimated that 5 million cases are caused by sudden cardiac death (SCD) annually. The primary cause of SCD is ventricular arrhythmias. Genomic studies have provided pathogenic, likely pathogenic, and variants of uncertain significance that may predispose individuals to cardiac causes of sudden death. In this study, we describe the case of a 43-year-old individual who experienced an episode of aborted SCD. An implantable cardioverter defibrillator was placed to prevent further SCD episodes. The diagnosis was ventricular fibrillation. Genomic analysis revealed some variants in the MYPN (pathogenic), GCKR (likely pathogenic), TTN (variant of uncertain significance), SCN5A (variant of uncertain significance), MYO6 (variant of uncertain significance), and ELN (variant of uncertain significance) genes, which could be associated with SCD episodes. In addition, a protein-protein interaction network was obtained, with proteins related to ventricular arrhythmia and the biological processes involved. Therefore, this study identified genetic variants that may be associated with and trigger SCD in the individual. Moreover, genetic variants of uncertain significance, which have not been reported, could contribute to the genetic basis of the disease.

Triglyceride-glucose index is associated with the occurrence and prognosis of cardiac arrest: a multicenter retrospective observational study

BACKGROUND

Triglyceride-glucose (TyG) index is an efficient indicator of insulin resistance and is proven to be a valuable marker in several cardiovascular diseases. However, the relationship between TyG index and cardiac arrest (CA) remains unclear. The present study aimed to investigate the association of the TyG index with the occurrence and clinical outcomes of CA.

METHODS

In this retrospective, multicenter, observational study, critically ill patients, including patients post-CA, were identified from the eICU Collaborative Research Database and evaluated. The TyG index for each patient was calculated using values of triglycerides and glucose recorded within 24 h of intensive care unit (ICU) admission. In-hospital mortality and ICU mortality were the primary clinical outcomes. Logistic regression, restricted cubic spline (RCS), and correlation analyses were performed to explore the relationship between the TyG index and clinical outcomes. Propensity score matching (PSM), overlap weighting (OW), and inverse probability of treatment weighting (IPTW) were adopted to balance the baseline characteristics of patients and minimize selection bias to confirm the robustness of the results. Subgroup analysis based on different modifiers was also performed.

RESULTS

Overall, 24,689 critically ill patients, including 1021 patients post-CA, were enrolled. The TyG index was significantly higher in patients post-CA than in those without CA (9.20 (8.72-9.69) vs. 8.89 (8.45-9.41)), and the TyG index had a moderate discrimination ability to identify patients with CA from the overall population (area under the curve = 0.625). Multivariate logistic regression indicated that the TyG index was an independent risk factor for in-hospital mortality (OR = 1.28, 95% CI: 1.03-1.58) and ICU mortality (OR = 1.27, 95% CI: 1.02-1.58) in patients post-CA. RCS curves revealed that an increased TyG index was linearly related to higher risks of in-hospital and ICU mortality (P for nonlinear: 0.225 and 0.271, respectively). Even after adjusting by PSM, IPTW, and OW, the TyG index remained a risk factor for in-hospital mortality and ICU mortality in patients experiencing CA, which was independent of age, BMI, sex, etc. Correlation analyses revealed that TyG index was negatively correlated with the neurological status of patients post-CA.

CONCLUSION

Elevated TyG index is significantly associated with the occurrence of CA and higher mortality risk in patients post-CA. Our findings extend the landscape of TyG index in cardiovascular diseases, which requires further prospective cohort study.

Does obesity influence ventricular repolarisation in children?

OBJECTIVE

Ventricular repolarisation changes may lead to sudden cardiac death in obese individuals. We aimed to investigate the relationship between ventricular repolarisation changes, echocardiographic parameters, anthropometric measures, and metabolic syndrome laboratory parameters in obese children.

METHODS

The study involved 81 obese and 82 normal-weight healthy children with a mean age of 12.3 ± 2.7 years. Anthropometric measurements of participants were evaluated according to nomograms. Obese patients were subdivided into two groups; metabolic syndrome and non-metabolic syndrome obese. Fasting plasma glucose, fasting insulin, and lipid profile were measured. QT/QTc interval, QT/QTc dispersions were measured, and left ventricular systolic and diastolic measurements were performed.

RESULTS

Body weight, body mass index, relative body mass index, waist/hip circumference ratio, and systolic and diastolic blood pressures were significantly higher in obese children. QT and QTc dispersions were significantly higher in obese children and also obese children with metabolic syndrome had significantly higher QT and QTc dispersions compared to non-metabolic syndrome obese children (p < 0.001) and normal-weight healthy children (p < 0.001). Waist/hip circumference ratio, body mass index, and relative body mass index were the most important determinant of QT and QTc dispersions. Left ventricular wall thickness (left ventricular posterior wall thickness at end-diastole, left ventricular posterior wall thickness at end-systole, interventricular septal thickness at end-diastole) and left ventricular mass index were significantly higher and ejection fraction was lower in obese children. Left ventricular mass index and interventricular septal thickness at end-diastole were positively correlated with QT and QTc dispersions.

CONCLUSIONS

Our study demonstrated that QT/ QTc interval prolongation and increase in QT and QTc dispersion on electrocardiogram may be found at an early age in obese children.

Sudden death in the young adult: a Tunisian autopsy-based series

Background

We aim to study the profile, and pathological characteristics of sudden death in young in purpose of recommendations for prevention.

Methods

We performed a retrospective cohort study using autopsy data from the Department of Forensic Medicine of Monastir (Tunisia). A review of all autopsies performed for 28 years was done (August 1990 to December 2018). In each case, clinical information, and circumstances of death were obtained. A complete forensic autopsy and histological, and toxicological investigations were performed. We have included all sudden death in persons aged between 18 and 35 years.

Results

We collected 137 cases of sudden death during the studied period. The mean age of the studied population was 26.47 years. Almost 72% deaths were classified as cardiac death, and was due to ischemic heart disease in 32.32%. Sudden death was attributed to a pleuropulmonary cause in 7.4%, an abdominal cause in 6%, and from a neurological origin in 4.5%. The cause of sudden death in this group was not established by 9.5%.

Conclusion

In this series, sudden death in young adults occurs mainly in a smoking male, aged between 18 and 24 years old, occurring at rest, in the morning, and early in the week. It is more common, especially in summer. Sudden death is most often the first manifestation of pathologies, especially unsuspected heart diseases. The predominance of cardiovascular causes is the common denominator of almost all studies reported in the literature. Our findings suggest that prevention of sudden death among young adults under the age of 35 years should also focus on evaluation for causes not associated with structural heart disease.

Symptoms and healthcare contact preceding sudden cardiac death in persons aged 1-49 years

Sudden Cardiac Death (SCD) is a leading cause of death among persons in their youth and early middle-age. To prevent SCD it is crucial to identify persons at high-risk of SCD. Knowledge of symptoms and medical contact prior to SCD could potentially aid in the identification of high-risk persons in the general population who would benefit from further investigation. This review aims to summarize the current knowledge of symptoms and healthcare contact preceding SCD in persons aged 1-49 years, and to explore how the symptoms differ according to SCD cause and age of the deceased. There was a high frequency of both cardiac and non-specific symptoms prior to SCD. Additionally, many SCD victims contacted the healthcare system prior to death on the basis of their symptoms and only a few were diagnosed with cardiovascular disease. This information underlines that young persons reporting potential cardiac symptoms should also be thoroughly examined. Furthermore, such symptoms could be used in combination with other easily accessible information in non-invasive prediction models aiming at identifying persons at high risk of SCD that would benefit from further investigation and possibly treatment.

Sudden Cardiac Arrest in Pediatrics

Sudden cardiac arrest (SCA) in the pediatric population is a rare and potentially devastating occurrence. An understanding of the differential diagnosis for the etiology of the cardiac arrest allows for the most effective emergency care and provides the patient with the best possible outcome. Pediatric SCA can occur with or without prodromal symptoms and may occur during exercise or rest. The most common cause is arrhythmia secondary to an underlying channelopathy, cardiomyopathy, or myocarditis. After stabilization, evaluation should include electrocardiogram, chest radiograph, and echocardiogram. Management should focus on decreasing the potential for recurring arrhythmia, maintaining cardiac preload, and thoughtful medication use to prevent exacerbation of the underlying condition. The purpose of this review was to provide the emergency physician with a concise and current review of the incidence, differential diagnosis, and management of pediatric patients presenting with SCA.