Risk stratification of sudden cardiac death: a review

Sudden cardiac death (SCD) is responsible for several millions of deaths every year and remains a major health problem. To reduce this burden, diagnosing and identification of high-risk individuals and disease-specific risk stratification are essential. Treatment strategies include treatment of the underlying disease with lifestyle advice and drugs and decisions to implant a primary prevention implantable cardioverter-defibrillator (ICD) and perform ablation of the ventricles and novel treatment modalities such as left cardiac sympathetic denervation in rare specific primary electric diseases such as long QT syndrome and catecholaminergic polymorphic ventricular tachycardia. This review summarizes the current knowledge on SCD risk according to underlying heart disease and discusses the future of SCD prevention.

Study on the Effect of Prehospital Emergency Nursing Model Based on Network Information Sharing Platform in Acute Ischemic Stroke

Background

Acute ischemic stroke is one of the most common emergencies in clinical medicine. Prehospital first aid of ischemic stroke has become the focus and focus of the global medical community. The combination of network information technology and prehospital first aid can better serve the treatment of ischemic stroke.

Objective

To explore the effect of prehospital emergency nursing model based on network information sharing platform in acute ischemic stroke.

Methods

78 patients with acute ischemic stroke from February 2020 to October 2021 were studied. Patients were randomly divided into study group (n = 39) and control group (n = 39). The control group was given routine first aid nursing. Prehospital first aid nursing based on network information sharing platform was used in the study group. Alarm response time, on-site first aid response time, hospital handover time, National Institutes of Health Stroke scale (NIHSS) at 12 and 24 hours after admission, Glasgow coma scale (GCS) at 12 and 24 hours after admission, incidence of poor prognosis, and nursing satisfaction score at 24 hours after admission were recorded.

Results

The emergency response time and hospital handover time in the study group were significantly shorter than those in the control group (P < 0.05). The NIHSS score and the incidence of poor prognosis at 12 and 24 hours after admission in the study group were lower than those in the control group (P < 0.05). The GCS scores at 12 hours and 24 hours after admission in the study group were higher than those in the control group (P < 0.05). The NSNS score of the study group was higher than that of the control group.

Conclusion

Prehospital first aid nursing based on network information sharing platform has great application value in patients with acute ischemic stroke. It can shorten the time of first aid, improve patients' consciousness, and reduce the incidence of poor prognosis.

Comparative Analysis of Emergency Medical Service Provider Workload During Simulated Out-of-Hospital Cardiac Arrest Resuscitation Using Standard Versus Experimental Protocols and Equipment

INTRODUCTION

Protocolized automation of critical, labor-intensive tasks for out-of-hospital cardiac arrest (OHCA) resuscitation may decrease Emergency Medical Services (EMS) provider workload. A simulation-based assessment method incorporating objective and self-reported metrics was developed and used to quantify workloads associated with standard and experimental approaches to OHCA resuscitation.

METHODS

Emergency Medical Services-Basic (EMT-B) and advanced life support (ALS) providers were randomized into two-provider mixed-level teams and fitted with heart rate (HR) monitors for continuous HR and energy expenditure (EE) monitoring. Subjects' resting salivary α-amylase (sAA) levels were measured along with Borg perceived exertion scores and multidimensional workload assessments (NASA-TLX). Each team engaged in the following three OHCA simulations: (1) baseline simulation in standard BLS/ALS roles; (2) repeat simulation in standard roles; and then (3) repeat simulation in reversed roles, ie, EMT-B provider performing ALS tasks. Control teams operated with standard state protocols and equipment; experimental teams used resuscitation-automating devices and accompanying goal-directed algorithmic protocol for simulations 2 and 3. Investigators video-recorded resuscitations and analyzed subjects' percent attained of maximal age-predicted HR (%mHR), EE, sAA, Borg, and NASA-TLX measurements.

RESULTS

Ten control and ten experimental teams completed the study (20 EMT-Basic; 1 EMT-Intermediate, 8 EMT-Cardiac, 11 EMT-Paramedic). Median %mHR, EE, sAA, Borg, and NASA-TLX scores did not differ between groups at rest. Overall multivariate analyses of variance did not detect significant differences; univariate analyses of variance for changes in %mHR, Borg, and NASA-TLX from resting state detected significant differences across simulations (workload reductions in experimental groups for simulations 2 and 3).

CONCLUSIONS

A simulation-based OHCA resuscitation performance and workload assessment method compared protocolized automation-assisted resuscitation with standard response. During exploratory application of the assessment method, subjects using the experimental approach appeared to experience reduced levels of physical exertion and perceived workload than control subjects.

Korean Cardiac Arrest Research Consortium (KoCARC): rationale, development, and implementation

OBJECTIVE

This study aimed to describe the conceptualization, development, and implementation processes of the newly established Korean Cardiac Arrest Resuscitation Consortium (KoCARC) to improve out-of-hospital cardiac arrest (OHCA) outcomes.

METHODS

The KoCARC was established in 2014 by recruiting hospitals willing to participate voluntarily. To enhance professionalism in research, seven research committees, the Epidemiology and Preventive Research Committee, Community Resuscitation Research Committee, Emergency Medical System Resuscitation Research Committee, Hospital Resuscitation Research Committee, Hypothermia and Postresuscitation Care Research Committee, Cardiac Care Resuscitation Committee, and Pediatric Resuscitation Research Committee, were organized under a steering committee. The KoCARC registry was developed with variables incorporated in the currently existing regional OHCA registries and Utstein templates and were collected via a web-based electronic database system. The KoCARC study population comprises patients visiting the participating hospitals who had been treated by the emergency medical system for OHCA presumed to have a cardiac etiology.

RESULTS

A total of 62 hospitals volunteered to participate in the KoCARC, which captures 33.0% of the study population in Korea. Web-based data collection started in October 2015, and to date (December 2016), there were 3,187 cases compiled in the registry collected from 32 hospitals.

CONCLUSION

The KoCARC is a self-funded, voluntary, hospital-based collaborative research network providing high level evidence in the field of OHCA and resuscitation. This paper will serve as a reference for subsequent KoCARC manuscripts and for data elements collected in the study.

Improvement of out-of-hospital cardiac arrest survival rate after implementation of the 2010 resuscitation guidelines

OBJECTIVE

The implementation of cardiopulmonary resuscitation guidelines, updated every five years, appears to improve patient survival rates after Out-Of-Hospital Cardiac Arrest (OHCA). The aim of this study is: 1) to measure the level of improvement in the prognosis of OHCA patient survival rates for the years 2009 and 2010 and the following two years 2011 and 2012; and 2) correlate the improvement in prognosis with the updated 2010 Advanced Cardiovascular Life Support (ACLS) Guidelines.

METHOD

We performed a retrospective observational study based on Geneva's OHCA register that includes data from January 1, 2009 to December 31, 2012. We compared the evolution of prognostic factors that influenced survival at hospital discharge between the periods before and after the implementation of the 2010 guidelines. We then compared the survival rates between each period. Finally, we adjusted the effects on survival in the second period to prognostic factors not linked with the care provided by Emergency Medical Services (EMS) teams, using a multivariable logistic regression model. Changes in advanced resuscitation treatment provided by EMS personnel were also examined.

RESULTS

795 OHCA were resuscitated between 1st January, 2009 and 31st December, 2012. The prognosis of patient survival at the time of hospital discharge rose from 10.33% in 2009-2010 to 17.01% in 2011-2012 (p = 0.007). After making adjustments for the effect of improved survival rates on the second period with factors not related to care provided by EMS teams, the odds ratio (OR) remains comparable (OR = 1.87, 95% CI [1.08-3.22]). Measured changes in treatment provided by EMS personnel were minor.

CONCLUSIONS

Survival rate for OHCA patients improved significantly in 2011-2012. This study suggests that it was probably the improvement in the quality of care provided during CPR and post-cardiac arrest care that have contributed to the increase in survival rates at the time of hospital discharge.

An analysis of the relationship between the applied medical rescue actions and the return of spontaneous circulation in adults with out-of-hospital sudden cardiac arrest

Sudden cardiac arrest (SCA) is a significant medical and social issue, the main cause of death in Europe and the United States.The aim of the research was to evaluate the effectiveness of emergency medical procedures applied by emergency medical teams in prehospital care in the context of return of spontaneous circulation (ROSC).The case-control study was based on the medical documentation of the Rescue Service in Katowice (responsible for monitoring 2.7 million inhabitants of the region) referring to 2016. The research involved exclusively adults (ie, individuals older than 18 years) with out-of-hospital cardiac arrest (OHCA). After considering the above inclusion criteria, there were 1603 dispatch order forms (0.64% of all dispatch orders) involved in further research.On the basis of the emergency medical procedure forms, the actions of emergency medical teams were verified as medical procedures (endotracheal intubation, the use of suction pumps, defibrillation, the use of alternatives providing airway patency and ROSC was determined.The analysis covered 1603 cases of OHCA. SCA turned out more frequent in men than in women (P = .000). Most often, SCA occurred in domestic conditions during the day and was witnessed by a third person. In 59.9% of the cases, actions were taken by witnesses, which increased the probability of ROSC. Patients were usually intubated (51.4%). Respirators were used less frequently (20.2%). Ventricular fibrillation (VF) was reported only in 22.0% of the cases. The ROSC rate was higher in the group of patients with diagnosed VF than in those with nonshockable rhythms (VF, 55.43% vs asystole, 24.05%; P = .000).Successful resuscitation depends on the quality of emergency medical procedures performed at the place of incident. The highest probability of ROSC is related with defibrillation (in the cases of VF or ventricular tachycardia with no pulse), intubation, the application of a respirator, and performing mechanical ventilation, as well as with a shorter time from dispatch to arrival.

Barriers and facilitators to public access defibrillation in out-of-hospital cardiac arrest: a systematic review

Public access defibrillation initiatives make automated external defibrillators available to the public. This facilitates earlier defibrillation of out-of-hospital cardiac arrest victims and could save many lives. It is currently only used for a minority of cases. The aim of this systematic review was to identify barriers and facilitators to public access defibrillation. A comprehensive literature review was undertaken defining formal search terms for a systematic review of the literature in March 2017. Studies were included if they considered reasons affecting the likelihood of public access defibrillation and presented original data. An electronic search strategy was devised searching MEDLINE and EMBASE, supplemented by bibliography and related-article searches. Given the low-quality and observational nature of the majority of articles, a narrative review was performed. Sixty-four articles were identified in the initial literature search. An additional four unique articles were identified from the electronic search strategies. The following themes were identified related to public access defibrillation: knowledge and awareness; willingness to use; acquisition and maintenance; availability and accessibility; training issues; registration and regulation; medicolegal issues; emergency medical services dispatch-assisted use of automated external defibrillators; automated external defibrillator-locator systems; demographic factors; other behavioural factors. In conclusion, several barriers and facilitators to public access defibrillation deployment were identified. However, the evidence is of very low quality and there is not enough information to inform changes in practice. This is an area in urgent need of further high-quality research if public access defibrillation is to be increased and more lives saved. PROSPERO registration number CRD42016035543.

Increased survival from out-of-hospital cardiac arrest when off duty medically educated personnel perform CPR compared with laymen

BACKGROUND

Bystander cardiopulmonary resuscitation (CPR) has been proved to save lives; however, whether survival is affected by the training level of the bystander is not fully described.

AIM

To describe if the training level of laymen and medically educated bystanders affect 30-day survival in out-of-hospital cardiac arrests (OHCA).

METHODS

This observational study included all witnessed and treated cases of bystander CPR reported to the Swedish Registry of Cardiopulmonary Resuscitation between 2010 and 2014. Bystander CPR was divided into two categories: (a) lay-byCPR (non-medically educated) and (b) med-byCPR (off duty medically educated personnel).

RESULTS

During 2010-2014, 24,643 patients were reported to the OHCA registry, of which 6850 received lay-byCPR and 1444 med-byCPR; 16,349 crew-witnessed and non-witnessed cases and those with missing information were excluded from the analysis. The median interval from collapse to call for emergency medical services was 2min in both groups (p=0.97) and 2min from collapse to start of CPR for lay-byCPR versus 1min for med-byCPR (p<0.0001). There were no significant differences in CPR methods used; 64.3% (lay-byCPR) and 65.7% (med-byCPR) applied compressions and ventilation, respectively (p=0.33). The 30-day survival was 14.7% for lay-byCPR and 17.2% for the med-byCPR group (p=0.02). The odds ratio adjusted for potential confounders regarding survival (med-byCPR versus lay-byCPR) was 1.34 (95% confidence interval, 1.11-1.62; p=0.002).

CONCLUSIONS

In cases of OHCA, medically educated bystanders initiated CPR earlier and an increased 30-day survival was found compared with laymen bystanders. These results support the need to improve the education programme for laypeople.

Timely bystander CPR improves outcomes despite longer EMS times

OBJECTIVES

This study aimed to determine the impact of bystander CPR on clinical outcomes in patients with increasing response time from collapse to EMS response.

METHODS

A population-based observational study was conducted in patients with witnessed out-of-hospital cardiac arrest (OHCA) of presumed cardiac etiology from 2012 to 2014. The time interval from collapse to CPR by EMS providers was categorized into quartile groups: fastest group (<4min), fast group (4 to <8min), late group (8 to <15min), and latest group (15 to <30min). The primary outcome was hospital discharge and the secondary outcome was survival with good neurological outcome. Multivariable logistic regression analysis was performed to evaluate the interaction between bystander CPR and the time interval from collapse to CPR by EMS providers.

RESULTS

A total of 15,354 OHCAs were analyzed. Bystander CPR was performed in 8591 (56.0%). Survival to hospital discharge occurred in 1632 (10.6%) and favorable neurological outcome in 996 (6.5%). In an interaction model of bystander CPR, compared to the fastest group, adjusted odds ratios (AORs) (95% CIs) for survival to discharge were 0.89 (0.66-1.20) in the fast group, 0.76 (0.57-1.02) in the late group, and 0.52 (0.37-0.73) in the latest group. For favorable neurological outcome, AORs were 1.12 (0.77-1.62) in the fast group, 0.90 (0.62-1.30) in the late group, 0.59 (0.38-0.91) in the latest group.

CONCLUSION

The survival from OHCA decreases as the ambulance response time increases. The increase in mortality and worsening neurologic outcomes appear to be mitigated in those patients who receive bystander CPR.

Neurology of cardiopulmonary resuscitation

This chapter aims to provide an up-to-date review of the science and clinical practice pertaining to neurologic injury after successful cardiopulmonary resuscitation. The past two decades have seen a major shift in the science and practice of cardiopulmonary resuscitation, with a major emphasis on postresuscitation neurologic care. This chapter provides a nuanced and thoughtful historic and bench-to-bedside overview of the neurologic aspects of cardiopulmonary resuscitation. A particular emphasis is made on the anatomy and pathophysiology of hypoxic-ischemic encephalopathy, up-to-date management of survivors of cardiopulmonary resuscitation, and a careful discussion on neurologic outcome prediction. Guidance to practice evidence-based clinical care when able and thoughtful, pragmatic suggestions for care where evidence is lacking are also provided. This chapter serves as both a useful clinical guide and an updated, thorough, and state-of-the-art reference on the topic for advanced students and experienced practitioners in the field.

Sudden death and cardiac arrest without phenotype: the utility of genetic testing

Approximately 4% of sudden cardiac deaths are unexplained [the sudden arrhythmic death syndrome (SADS)], and up to 6-10% of survivors of cardiac arrest do not have an identifiable cardiac abnormality after comprehensive clinical evaluation [idiopathic ventricular fibrillation (IVF)]. Genetic testing may be able to play a role in diagnostics and can be targeted to an underlying phenotype present in family members following clinical evaluation. Alternatively, post-mortem genetic testing (the "molecular autopsy") may diagnose the underlying cause if a clearly pathogenic rare variant is found. Limitations include a modest yield, and the high probability of finding a variant of unknown significance (VUS) leading to a low signal-to-noise ratio. Next generation sequencing enables cost-efficient high throughput screening of a larger number of genes but at the expense of increased genetic noise. The yield from genetic testing is even lower in IVF in the absence of any suggestion of another phenotype in the index case or his/her family, and should be actively discouraged at this time. Future improvements in diagnostic utility include optimization of the use of variant-calling pipelines and shared databases as well as patient-specific models of disease to more accurately assign pathogenicity of variants. Studying "trios" of parents and the index case may better assess the yield of sporadic and recessive disease.

Better management of out-of-hospital cardiac arrest increases survival rate and improves neurological outcome in the Swiss Canton Ticino

Aim

To determine the incidence of out-of-hospital cardiac arrest (OHCA) fulfilling Utstein criteria in the Canton Ticino, Switzerland, the survival rate of OHCA patients and their neurological outcome.

Methods and results

All OHCAs treated in Canton Ticino between 1 January 2005 and 31 December 2014 were followed until either death or hospital discharge. The survival and neurological outcome of those OHCA fulfilling Utstein criteria are reported. A total of 3367 OHCAs occurred in the Canton Ticino over a 10-year period. Resuscitation was attempted in 2298 patients; of those 1492 (65%) were of presumed cardiac origin, 454 fulfilling the Utstein comparator criteria. About 69% [95% confidence interval (CI), 66.6–71.4%] of the patients had a bystander-witnessed arrest; a dispatched cardiopulmonary resuscitation (CPR) steadily and significantly increased from 2005 to 2014. Out-of-hospital cardiac arrest occurred prevalently home (67%), in men (71%) of a mean age of 71 ± 13 years. There were no statistically significant differences either in demographic characteristics of OHCA victims over these years or in presenting rhythm. There was a progressive increase in the survival at discharge from 15% in 2005 to 55% in 2014; overall 96% (95% CI, 93.3–99.9%) of the survivors had a good neurological outcome.

Conclusion

The significant increase in Utstein comparator survival rates and improved neurological outcome in OHCA victims in Canton Ticino are the result of an effective OHCA management programme which includes large-scale public education, a coordinated fast EMS response, high density of external defibrillators, and advances in clinical interventions for OHCAs.

Evolution of European Union legislation on emergency research

AIM

Emergency research is necessary to prevent exposure of patients to unvalidated clinical practice (nonmaleficence), and to improve the dismal prognosis of disorders requiring emergent treatment such as cardiac arrest (beneficence). Regulations that govern clinical research should conform to bioethical principles of respect for nonmaleficence, beneficence, autonomy, and justice. Our objectives are to review the evolution of European Union (EU) legislation on emergency research, and to identify potentially remaining problems.

DATA SOURCES

EU legislative sources on clinical research and medical literature describing the impact of EU Regulations on emergency research.

RESULTS

Article 5 of EU Directive 2001/20/EC required consent before enrolment in a research study to ensure the autonomy of potentially incapacitated research subjects. However, obtaining such consent is often impossible in emergency situations. Directive 2001/20/EC was criticized for potentially preventing emergency research. Several EU Member States addressed this problem by permitting deferred consent. International ethical guidelines supporting deferred consent were also cited by Good Clinical Practice Directive 2005/28/EC. However, Directive 2001/20/EC was not revised to achieve harmonization of EU emergency research, thus resulting in ongoing "ambiguity" as regards to emergency research legitimacy. This will be definitively addressed by applying EU Regulation No. 536/2014 and repealing Directive 2001/20/EC. The new EU Regulation permits using deferred consent under clearly specified conditions, and may foster emergency research that evaluates interventions posing minimal risk relative to standard practice.

CONCLUSIONS

Legislation related to emergency research in Europe has evolved to increase concordance with bioethical principles so as to increase evidence-based improvements in emergency care.

The clinical challenge of preventing sudden cardiac death immediately after acute ST-elevation myocardial infarction

Unfortunately, of all patients experiencing acute myocardial infarction (MI), usually in the form of ST-elevation MI, 25-35% will die of sudden cardiac death (SCD) before receiving medical attention, most often from ventricular fibrillation. For patients who reach the hospital, prognosis is considerably better and has improved over the years. Reperfusion therapy, best attained with primary percutaneous coronary intervention compared to thrombolysis, has made a big difference in reducing the risk of SCD early and late after ST-elevation MI. In-hospital SCD due to ventricular tachyarrhythmias is manageable, with either preventive measures or drugs or electrical cardioversion. There is general agreement for secondary prevention of SCD post-MI with implantation of a cardioverter defibrillator (ICD) when malignant ventricular arrhythmias occur late (>48 h) after an MI, and are not due to reversible or correctable causes. The major challenge remains that of primary prevention, that is, how to prevent SCD during the first 1-3 months after ST-elevation MI for patients who have low left ventricular ejection fraction and are not candidates for an ICD according to current guidelines, due to the results of two studies, which did not show any benefits of early (<40 days after an MI) ICD implantation. Two recent documents may provide direction as to how to bridge the gap for this early post-MI period. Both recommend an electrophysiology study to guide implantation of an ICD, at least for those developing syncope or non-sustained ventricular tachycardia, who have an inducible sustained ventricular tachycardia at the electrophysiology study. An ICD is also recommended for patients with indication for a permanent pacemaker due to bradyarrhythmias, who also meet primary prevention criteria for SCD.

Sports preparticipation cardiac screening: what about children?

Sudden cardiac death in young athletes is a devastating event. Screening programs have been proposed to prevent sudden cardiac death in young athletes. Mortality rates and causes of death differ among young adults and children. Children have a considerably lower incidence of sudden cardiac death. Data lack to compare athletes and non-athletes in childhood, but 40-50 % of sudden cardiac death in this age group seems to be related to exercise. Screening programs including history and physical exam are not very sensitive or specific and will result in important numbers of false-positives and false-negatives. Especially, interpretation of ECG in children is different from ECG in adults, with less accurate diagnoses as a consequence. Secondary prevention by widespread education of simple resuscitation techniques and use of automatic external defibrillators if available will probably save as many lives as any screening program.

CONCLUSION

Sufficient data are lacking to support general preparticipation screening with history, physical exam, and ECG in competitive children. Nevertheless, the impact of such a program, together with secondary preventive measures, should be evaluated in large prospective studies.