Disaster Events and the Risk of Sudden Cardiac Death: A Washington State Investigation

Impact of Earthquake on Cardiovascular Health: What Should Cardiovascular Healthcare Providers Anticipate After the Devastating Earthquakes in Turkey and Syria?

Natural disasters like earthquakes have direct and indirect association with major adverse cardiac events. They can impact cardiovascular health by multiple mechanisms not to mention their impact on cardiovascular care and services. Besides the humanitarian tragedy that calls attention globally, we as part of cardiovascular community are concerned with the short and long outcomes of those who survived the recent Turkey and Syria earthquake tragedy. Therefore, in this review, we aimed to draw attention of cardiovascular healthcare providers to the anticipated cardiovascular issues that may arise in survivors on short- and long-term postearthquakes to ensure proper screening and earlier management of this population. With the anticipated increase in natural disasters in future considering climate changes, geological factors, and human activities, the cardiovascular healthcare providers as part of medical community should be aware of the high rate of cardiovascular disease burden that can occur among survivors of earthquakes and other natural disasters, so, they should act accordingly in terms of preparedness measures, adequate response planning starting from services re-allocation to personnel training and enhancing access to medical and cardiac care in both acute and chronic contexts, not to mention screening and risk-stratifying the patients to optimize their management.

Ischemic Heart Disease Related Sudden Cardiac Death in Autopsied Cases: An Egyptian perspective

ABSTRACT

Diagnosis of the underlying cause of sudden unexpected death in a previously healthy individual remains one of the important challenges in forensic practice. Ischemic heart disease is the most common cause of sudden death. The current study aims to investigate the incidence and pathology of sudden ischemic cardiac death in Egypt. All cases of sudden cardiac death (SCD) examined by different forensic departments throughout Egypt during the period of January 2010 through December 2014 were included. Cases underwent complete autopsy examination including a thorough gross and microscopic examination of the heart and great blood vessels. Of 535 cases of SCD diagnosed during the period of the study, coronary atherosclerosis was the principle finding in 420 (78.5%) cases. The highest numbers of deaths were reported in fifth and sixth decades with male preference. Other causes of SCD included myocarditis, cardiomyopathies, valvular heart disease, and hypertensive heart disease (7.8%, 4.1%, 4.1%, and 2.8%, respectively). There was severe stenosis (>75%) of at least 1 coronary artery in 74% of cases. Type VI atherosclerosis was found in 40.7% of cases. The left anterior descending branch was the most affected artery by atherosclerosis. Acute coronary pathological events were demonstrated in 27.6% of cases. Recent myocardial infarction was evident in 55.5% of cases, whereas old infarcts were demonstrated in 44.5% of cases. Features of hypertensive heart disease were present in 18.3% of cases. In conclusion, ischemic heart disease is the leading cause of SCD in Egypt.

Anxiety, Mental Stress, and Sudden Cardiac Arrest: Epidemiology, Possible Mechanisms and Future Research

Sudden cardiac arrest (SCA) is a leading cause of mortality and morbidity in affluent societies, which underscores the need to identify persons at risk. The etiology of SCA is however complex, with predisposing and precipitating factors interacting. Although anxiety and mental stress have been linked to SCA for decades, their precise role and impact remain unclear and the biological underpinnings are insufficiently understood. In this paper, we systematically reviewed various types of observational studies (total n = 20) examining the association between anxiety or mental stress and SCA. Multiple methodological considerations challenged the summarizing and interpretation of the findings. For anxiety, the overall picture suggests that it predisposes for SCA in physically healthy populations (unadjusted OR = 2.44; 95% CI: 1.06-5.59; n = 3). However, in populations at risk for SCA (n = 4), associations were heterogeneous but not significant. Anxiety may partly predispose to SCA by contributing to other risk factors such as cardiovascular disease and diabetes mellitus via mechanisms such as unhealthy lifestyle and metabolic abnormalities. Mental stress appears to precipitate SCA, presumably by more directly impacting on the cardiac ion channels that control the heart's electrical properties. This may lead to ventricular fibrillation, the arrhythmia that underlies SCA. To advance this field of research, experimental studies that unravel the underlying biological mechanisms are deemed important, and most easily designed for mental stress as a precipitating factor because of the short timeframe. These proof-of-concept studies should examine the whole pathway from the brain to the autonomic nervous system, and eventually to cardiac ion channels. Ultimately, such studies may facilitate the identification of persons at risk and the development of novel preventive strategies.

BAYESIAN INFERENCE OF HIDDEN GAMMA WEAR PROCESS MODEL FOR SURVIVAL DATA WITH TIES

Survival data often contain tied event times. Inference without careful treatment of the ties can lead to biased estimates. This paper develops the Bayesian analysis of a stochastic wear process model to fit survival data that might have a large number of ties. Under a general wear process model, we derive the likelihood of parameters. When the wear process is a Gamma process, the likelihood has a semi-closed form that allows posterior sampling to be carried out for the parameters, hence achieving model selection using Bayesian deviance information criterion. An innovative simulation algorithm via direct forward sampling and Gibbs sampling is developed to sample event times that may have ties in the presence of arbitrary covariates; this provides a tool to assess the precision of inference. An extensive simulation study is reported and a data set is used to further illustrate the proposed methodology.

Burden of cardiovascular morbidity and mortality following humanitarian emergencies: a systematic literature review

BACKGROUND

The global burden of cardiovascular mortality is increasing, as is the number of large-scale humanitarian emergencies. The interaction between these phenomena is not well understood. This review aims to clarify the relationship between humanitarian emergencies and cardiovascular morbidity and mortality.

METHODS

With assistance from a research librarian, electronic databases (PubMed, Scopus, CINAHL, and Global Health) were searched in January 2014. Findings were supplemented by reviewing citations of included trials. Observational studies reporting the effect of natural disasters and conflict events on cardiovascular morbidity and mortality in adults since 1997 were included. Studies without a comparison group were not included. Double-data extraction was utilized to abstract information on acute coronary syndrome (ACS), acute decompensated heart failure (ADHF), and sudden cardiac death (SCD). Review Manager 5.0 (Version 5.2, The Nordic Cochrane Centre; Copenhagen Denmark,) was used to create figures for qualitative synthesis.

RESULTS

The search retrieved 1,697 unique records; 24 studies were included (17 studies of natural disasters and seven studies of conflict). These studies involved 14,583 cardiac events. All studies utilized retrospective designs: four were population-based, 15 were single-center, and five were multicenter studies. Twenty-three studies utilized historical controls in the primary analysis, and one utilized primarily geographical controls.

DISCUSSION

Conflicts are associated with an increase in long-term morbidity from ACS; the short-term effects of conflict vary by study. Natural disasters exhibit heterogeneous effects, including increased occurrence of ACS, ADHF, and SCD.

CONCLUSIONS

In certain settings, humanitarian emergencies are associated with increased cardiac morbidity and mortality that may persist for years following the event. Humanitarian aid organizations should consider morbidity from noncommunicable disease when planning relief and recuperation projects.

Point-of-Care Testing at the Disaster-Emergency-Critical Care Interface

Point-of-care (POC) testing allows for medical testing to be performed across the disaster-emergency-critical care continuum. The disaster-emergency-critical care continuum begins with the identification of at-risk patients, followed by patient stabilization, and ultimately transfer to an alternate care facility or mobile hospital for comprehensive critical care. Gaps at the interfaces for each of these settings leads to excess mortality and morbidity. Disaster victims are at risk for acute myocardial infarctions, acute kidney injury (AKI), and sepsis. However cardiac biomarker testing, renal function testing, and multiplex rapid pathogen detection are often unavailable or inadequate during disasters. Cardiac biomarker reagents require refrigeration; traditional renal function tests (i.e., serum creatinine) exhibit poor sensitivity for predicting AKI in critically ill patients, and culture-based pathogen detection is too slow to help initiate early-directed antimicrobial therapy. We propose three value propositions detailing how rapid, POC, and environmentally hardened cardiac biomarker, AKI and multiplex pathogen testing harmonizes the interface between disaster, emergency, and critical care.

Medical complications associated with earthquakes

Major earthquakes are some of the most devastating natural disasters. The epidemiology of earthquake-related injuries and mortality is unique for these disasters. Because earthquakes frequently affect populous urban areas with poor structural standards, they often result in high death rates and mass casualties with many traumatic injuries. These injuries are highly mechanical and often multisystem, requiring intensive curative medical and surgical care at a time when the local and regional medical response capacities have been at least partly disrupted. Many patients surviving blunt and penetrating trauma and crush injuries have subsequent complications that lead to additional morbidity and mortality. Here, we review and summarise earthquake-induced injuries and medical complications affecting major organ systems.

The effect of acute psychological stress on QT dispersion in patients with coronary artery disease

BACKGROUND

An acute psychological stress can precipitate ventricular arrhythmias and sudden cardiac death in patients with coronary artery disease (CAD). However, the physiologic mechanisms by which these effects occur are not entirely clear. Mental stress-induced myocardial ischemia occurs in a significant percentage of the CAD population. It is unknown if the proarrhythmic effects of psychological stress are mediated through the development of myocardial ischemia.

OBJECTIVES

To examine the effects of psychological stress on QT dispersion (QTd) among CAD patients and whether these effects are mediated via the development of myocardial ischemia.

METHODS

Psychological stress was induced using a public speaking task. Twelve-lead electrocardiograms (ECG) were recorded at rest, during mental stress, and during recovery. QTd was calculated as the difference between the longest and the shortest QT interval in the 12-lead ECG. Rest-stress myocardial perfusion imaging was also performed to detect mental stress-induced myocardial ischemia.

RESULTS

Mental stress induced a significant increase in QTd compared to the resting condition (P < 0.001). This effect persisted beyond the first 10 minutes of recovery (P < 0.001). QTd was significantly associated with the development of mental stress ischemia with ischemic patients having significantly higher QTd during mental stress than nonischemic patients (P = 0.006). This finding remained significant after controlling for possible confounding factors (P = 0.01).

CONCLUSION

An acute psychological stress induces a significant increase in QTd, which persists for more than 10 minutes after the cessation of the stressor. This effect seems to be, at least partially, mediated by the development of mental stress-induced myocardial ischemia.