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...diac and noncardiac related diseases are also well recognised, as initiallysdisputed (Table 1). Sudden out of hospital cardiac arrest accounts for around 0.5 - 1 deaths per 1000 population everysyear =-=[2]-=-. In North America alone, more than 300.000 deathssper year are attributed to SCA [3]. The survival rate has remained very low for several decades, with only 8-10 % ofspatients surviving to hospital d...

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...y post-ROSC intervention shown to improve survival from OHCA [38]. Twosmajor randomised clinical trials (the Hypothermia AftersCardiac Arrest trial from Europe [39] and a smaller trialsfrom Australia =-=[40]-=-) have demonstrated the efficacy of thissintervention. The exact mechanism of the protective effectssFig. (1). Algorithm for Advanced Life Support (ALS) [21].s320sCurrent Cardiology Reviews, 2013, Vol...

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... attributed to SCA [3]. The survival rate has remained very low for several decades, with only 8-10 % ofspatients surviving to hospital discharge and in many ruralsareas survival is dramatically less =-=[4]-=-. Survival and longterm functional outcome are closely related to the underlyingscause such as initial rhythm.sRISK FACTORS FOR SUDDEN CARDIAC DEATHsThe high mortality associated with SCA emphasises t...

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...tic resonance imaging (MRI) but also genetic testing may be useful in thisssetting.sMANAGEMENT OF SCAsThe European Resuscitation Council (ERC) updated theirsguidelines on the treatment of SCA in 2010 =-=[21]-=-. The mainschanges compared to the 2005 guidelines in Basic Life Support (BLS) were the introduction of a compression/ventilation ratio of 30:2 as compared to 15:2 to optimizesmaintenance of circulati...

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... refers to the European Society of Cardiology (ESC) guidelines on decision making on implantablescardioverter defibrillator (ICD) implantation for secondarysprevention of SCA due to severe arrhythmia =-=[57, 58]-=-. Additional therapies including VT ablation or permanent antiarrhythmic therapy may be warranted in selected cases. However, as outlined previously severe arrhythmias are closelysrelated to an impair...

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... refers to the European Society of Cardiology (ESC) guidelines on decision making on implantablescardioverter defibrillator (ICD) implantation for secondarysprevention of SCA due to severe arrhythmia =-=[57, 58]-=-. Additional therapies including VT ablation or permanent antiarrhythmic therapy may be warranted in selected cases. However, as outlined previously severe arrhythmias are closelysrelated to an impair...

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...pertrophic cardiomyopathy, abnormal origin of the coronary arteries, myocarditis, arrhythmic right ventricular cardiomyopathy (ARVC), mitral valve prolapse, aortic stenosis, coronarysarteriosclerosis =-=[19]-=-. The European Society of Cardiologys(ESC) has published guidelines for the pre-participationsscreening of young competitive athletes in 2005 [20]:s• Complete personal and family history and physicals...

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...(Table 1). Sudden out of hospital cardiac arrest accounts for around 0.5 - 1 deaths per 1000 population everysyear [2]. In North America alone, more than 300.000 deathssper year are attributed to SCA =-=[3]-=-. The survival rate has remained very low for several decades, with only 8-10 % ofspatients surviving to hospital discharge and in many ruralsareas survival is dramatically less [4]. Survival and long...

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...>35°C body temperature. Moreover, leucocyte function maysbe decreased resulting in an increased risk for infectionss[39]. On the ECG, bradycardia and a prolongation of the QTsinterval may be detected =-=[52]-=-. In rare cases, severe arrhythmias are provoked by MTH. Further, due to renal side effects, the electrolyte balance may be altered and carefulsmonitoring is mandatory [53, 54]. Additionally, the meta...

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... prolapse, aortic stenosis, coronarysarteriosclerosis [19]. The European Society of Cardiologys(ESC) has published guidelines for the pre-participationsscreening of young competitive athletes in 2005 =-=[20]-=-:s• Complete personal and family history and physicalsexaminations• 12 lead ECGs• Any abnormal findings warrant further examinations(e.g. echocardiography or cardiac magnetic resonance imaging (CMR)s•...

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... witnessedscardiac arrest [64]. In the vast majority of patients, ventricular fibrillation will not terminate spontaneously and thesprobability to survive will decline by 10% per minute of ongoing VF =-=[65]-=-. Ideally, a regular pulse is restored within 10sminutes of CPR [66].sIn a study including 200 patients presenting with ventricular fibrillation and successful early defibrillation, 72%sof patients su...

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...QTsinterval may be detected [52]. In rare cases, severe arrhythmias are provoked by MTH. Further, due to renal side effects, the electrolyte balance may be altered and carefulsmonitoring is mandatory =-=[53, 54]-=-. Additionally, the metabolisation of several drugs may be altered by MTH [54].sSECONDARY PREVENTION OF SCAsIn patients who survived SCA, strategies are needed tosprevent future, potentially fatal eve...

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...coronary arterysdisease is the most important cause of SCA, cardiovascularsrisk factors also increase the risk of OHCA and this is especially the case for diabetes and smoking but less so for obesity =-=[8, 9]-=-.sHowever, our understanding of the relationship betweensacute myocardial ischemia and its most fatal immediates*Address for correspondence to this author at the Senior Lecturer and Consultant Cardiol...

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...aterals [12]. Furthermore, a well-developed collateral circulation has been associated with reduced risk for cardiac and all-cause mortality in patients with stable coronary artery disease in generals=-=[13]-=-.sELECTROPHYSIOLOGICAL RISK ASSESSMENTsTesting of the electrical vulnerability to ventricular arrhythmia remains elusive. This is primarily due to the dynamic nature of the electrophysiological behavi...

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... the hospital they are admitted to [70] and there isssome evidence that mortality is lower among those admittedsto intensive care units (ICUs) that treat a high volume ofspost-cardiac arrest patients =-=[71]-=-. A specialised multidisciplinary team approach to post-resuscitation care is essential.sPost-resuscitation care is started by the EMS on scene and inssome systems this may include pre-hospital induct...

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...ucial. Several non-randomised observationalsstudies have demonstrated survival benefit from early angiography post-OHCA compared to no coronary angiographysor percutaneous coronary intervention (PCI) =-=[29, 30]-=-. However, other studies have also highlighted an increased complication risk if early angiography is performed in these patients [31]. In our view, although the role of immediate coroTable 2. Diagnos...

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...tervention. For example, in patients withscardiogenic shock, an intra-aortic balloon pump (IABP) orsother support devices (e.g. Impella 2.5) can be inserted atsthis occasion to augment cardiac output =-=[32]-=-.sMoreover, approximately 80% of OHCA presentingswith VF or VT are cardiac in origin and these patients maysbenefit from an early PCI [33]. Studies are currently undersway to determine whether patient...

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...coronary arterysdisease is the most important cause of SCA, cardiovascularsrisk factors also increase the risk of OHCA and this is especially the case for diabetes and smoking but less so for obesity =-=[8, 9]-=-.sHowever, our understanding of the relationship betweensacute myocardial ischemia and its most fatal immediates*Address for correspondence to this author at the Senior Lecturer and Consultant Cardiol...

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...is determined by several factors. In case of asystole or PEA as the initial rhythm,sa prolonged cardiac arrest must be assumed and thereforesonly 10% of patients will survive until hospital admissions=-=[62, 63]-=-. In contrast, outcome is much better in patients withsventricular arrhythmias, especially in those with a witnessedscardiac arrest [64]. In the vast majority of patients, ventricular fibrillation wil...

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.... However, as outlined previously severe arrhythmias are closelysrelated to an impaired left ventricular function, and an optimal heart failure management will be mandatory in this patient population =-=[59]-=-.sPROGNOSIS AFTER SCAsThe Time to defibrillation and other factors such as bystander CPR, has not improved over precise time [60]. Theschain of survival (Fig. 2) is changing over time and it isslikely...

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...he inducibility of ventricular arrhythmiashas been advocated, the validity of this approach is uncertain. Non-invasive investigations have been developed tosestimate the susceptibility to arrhythmias =-=[14]-=-. These testssexamine different aspects of myocardial electrophysiologysas reflected on the surface electrocardiogram (ECG),snamely change of autonomic function due to increased circulating catecholam...

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...is determined by several factors. In case of asystole or PEA as the initial rhythm,sa prolonged cardiac arrest must be assumed and thereforesonly 10% of patients will survive until hospital admissions=-=[62, 63]-=-. In contrast, outcome is much better in patients withsventricular arrhythmias, especially in those with a witnessedscardiac arrest [64]. In the vast majority of patients, ventricular fibrillation wil...

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...onary angiographysor percutaneous coronary intervention (PCI) [29, 30]. However, other studies have also highlighted an increased complication risk if early angiography is performed in these patients =-=[31]-=-. In our view, although the role of immediate coroTable 2. Diagnostic Investigations for Patients After OHCAsHistory and physical examinations• Prior diagnoses of heart diseases, concomitant diseases?...

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...al chest compression devices (e.g., LUCASs(Jolife, Lund, Sweden) and AutoPulse (Zoll Circulation,sChelmsford, Massachusetts, USA) adequate chest compression quality can be maintained during transport =-=[24]-=-. However, there is currently insufficient evidence for a clear advantage over manual chest compressions with regard tosclinical outcomes when using the LUCAS device [25]. Similarly, the Circulation I...

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...ucial. Several non-randomised observationalsstudies have demonstrated survival benefit from early angiography post-OHCA compared to no coronary angiographysor percutaneous coronary intervention (PCI) =-=[29, 30]-=-. However, other studies have also highlighted an increased complication risk if early angiography is performed in these patients [31]. In our view, although the role of immediate coroTable 2. Diagnos...

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...to sustained ventricular tachycardia (VT)/ventricular fibrillation (VF), asystole orspulseless electric activity (PEA). There are also non-cardiacsetiologies for sudden circulatory collapse (Table 1) =-=[1]-=-. Thesmost common cause of cardiac arrest is acute or chronicscoronary artery disease but various other cardiac and noncardiac related diseases are also well recognised, as initiallysdisputed (Table 1...

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...arction showed lower incidence for malignantsarrhythmias (defined as VF, VT or high degree atrioventricular (AV) block and lower mortality in patients withsangiographically well-developed collaterals =-=[12]-=-. Furthermore, a well-developed collateral circulation has been associated with reduced risk for cardiac and all-cause mortality in patients with stable coronary artery disease in generals[13].sELECTR...

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...determine whether patients who fail to achieve return of spontaneous circulation (ROSC) at the scene andswho are suspected to have obstructive CAD may benefitsfrom PCI whilst receiving continuous CPR =-=[34]-=-. Importantly, PCI plays a major role in the improved survivalsrates [35, 36]. In a study of 714 OHCA patients referred tosa tertiary centre in Paris, 435 (61%) had no obvious extracardiac cause. This...

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...ospital? Some experimental studies suggest that early cooling improves outcome; butsa randomised clinical trial failed to show superiority for prehospital cooling versus in-hospital initiated cooling =-=[42]-=-. Thestime frame during which MTH can be initiated is unknown.sThe length of time MTH should be maintained is also uncertain. In the Australian trial patients were cooled for 12 hourss[40], while in t...

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...p options being available.sHowever, in patients with MTH several side effects maysoccur. MTH may affect the coagulation cascade and plateletsfunction, eventually leading to an increased bleeding risks=-=[50, 51]-=-. In case of bleeding, the patient should be rewarmeds>35°C body temperature. Moreover, leucocyte function maysbe decreased resulting in an increased risk for infectionss[39]. On the ECG, bradycardia ...

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...sonly 10% of patients will survive until hospital admissions[62, 63]. In contrast, outcome is much better in patients withsventricular arrhythmias, especially in those with a witnessedscardiac arrest =-=[64]-=-. In the vast majority of patients, ventricular fibrillation will not terminate spontaneously and thesprobability to survive will decline by 10% per minute of ongoing VF [65]. Ideally, a regular pulse...

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...estimatesthe impact of hypoxic brain injury, such as the levels of thesprotein “neurone specific enolase”, “S-100” or “IL-8”, although predictive value and accuracy varies widely in different studies =-=[67, 68]-=-. More precise tools to predict outcomesswould help tremendously for optimal resource allocations[69].sCARDIAC ARREST CENTRESsThere is variation in outcome for OHCA patients depending on the hospital ...

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...s model might besapplicable to other medical conditions such as OHCA orsstroke. Based on this premise, regionalised, coordinated resuscitation centres to care for post-OHCA patients has beensproposed =-=[72]-=-. EMS providers should transport patients tosthose hospitals that are best suited for caring for OHCA victims - such hospitals would provide therapeutic hypothermia,s24/7 access to PCI facilities and ...

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... the circumstance of hypothermia, the concept of therapeutic hypothermia has been proposed in patients with OHCA. As to date, it is the only post-ROSC intervention shown to improve survival from OHCA =-=[38]-=-. Twosmajor randomised clinical trials (the Hypothermia AftersCardiac Arrest trial from Europe [39] and a smaller trialsfrom Australia [40]) have demonstrated the efficacy of thissintervention. The ex...

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...olingsblankets and ice packs to the axilla, groin and neck, hassalso been advocated. These devices are simple, require lesssoperator experience, and are inexpensive, but initial coolingsmay be slower =-=[45]-=-. One study has shown that both intravascular and surface cooling are equivalent in their effectiveness to reach and maintain core temperatures [46],salthough another showed better temperature control...

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... induction of hypothermia and early coronary intervention. Overall, suchschanges have increased the survival rate. In Sweden for instance, the survival rate after OHCA has doubled over theslast years =-=[61]-=-.sThe prognosis after cardiac arrest is determined by several factors. In case of asystole or PEA as the initial rhythm,sa prolonged cardiac arrest must be assumed and thereforesonly 10% of patients w...

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...5) can be inserted atsthis occasion to augment cardiac output [32].sMoreover, approximately 80% of OHCA presentingswith VF or VT are cardiac in origin and these patients maysbenefit from an early PCI =-=[33]-=-. Studies are currently undersway to determine whether patients who fail to achieve return of spontaneous circulation (ROSC) at the scene andswho are suspected to have obstructive CAD may benefitsfrom...

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...phy and 70% of those had at least one significantscoronary lesion [30].sTo facilitate decision making, an ECG should be recorded as soon as possible after ROSC to assess for STelevation or (new) LBBB =-=[37]-=-. However, the ECG has a limited accuracy in the setting of SCA. The absence of STsegment elevation does not exclude the presence of criticalscoronary stenoses. In approximately 50% of OHCA survivors ...

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...whilst invasive cooling methods include cold intra-venousssaline or intra-vascular cooling catheters. Recently, intranasal evaporative cooling has been shown to produce effective pre-hospital cooling =-=[44]-=-. However, 30 mL/kg of intravenous 4°C saline or Hartmann’s solution is the simplestsand most cost effective method for pre-hospital setting. Thestarget core temperature is 33 ± 1°C. Intravascular dev...

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...QTsinterval may be detected [52]. In rare cases, severe arrhythmias are provoked by MTH. Further, due to renal side effects, the electrolyte balance may be altered and carefulsmonitoring is mandatory =-=[53, 54]-=-. Additionally, the metabolisation of several drugs may be altered by MTH [54].sSECONDARY PREVENTION OF SCAsIn patients who survived SCA, strategies are needed tosprevent future, potentially fatal eve...

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...ntricular fibrillation will not terminate spontaneously and thesprobability to survive will decline by 10% per minute of ongoing VF [65]. Ideally, a regular pulse is restored within 10sminutes of CPR =-=[66]-=-.sIn a study including 200 patients presenting with ventricular fibrillation and successful early defibrillation, 72%sof patients survived until hospital admission. However, onlys40% of these patients...

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...ertain. In the Australian trial patients were cooled for 12 hourss[40], while in the Hypothermia After Cardiac Arrests(HACA) trial they were cooled for 24 hours [39]. Longersduration may be superior. =-=[43]-=-sThe optimal cooling method is not yet clear [38]. External cooling methods include cold pads and cooling caps,swhilst invasive cooling methods include cold intra-venousssaline or intra-vascular cooli...

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...sworld. In a recent trial of an impedance threshold device forsOHCA in the United States and Canada, just 48% of thes2289 enrolled patients admitted hospital were treated withstherapeutic hypothermia =-=[48]-=-. On the other hand, in the UKs86% of intensive care units had implemented hypothermiasby 2009 [49]. Lack of resources and cost of MTH are commonly cited as barriers to implementation, despite relativ...

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...p options being available.sHowever, in patients with MTH several side effects maysoccur. MTH may affect the coagulation cascade and plateletsfunction, eventually leading to an increased bleeding risks=-=[50, 51]-=-. In case of bleeding, the patient should be rewarmeds>35°C body temperature. Moreover, leucocyte function maysbe decreased resulting in an increased risk for infectionss[39]. On the ECG, bradycardia ...

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...to predict outcomesswould help tremendously for optimal resource allocations[69].sCARDIAC ARREST CENTRESsThere is variation in outcome for OHCA patients depending on the hospital they are admitted to =-=[70]-=- and there isssome evidence that mortality is lower among those admittedsto intensive care units (ICUs) that treat a high volume ofspost-cardiac arrest patients [71]. A specialised multidisciplinary t...

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...20s3456 7897; E-mail: pascalmeier74@gmail.com; www.drpascalmeier.comsconsequence, cardiac arrhythmia, remains very limited. Wesknow that ischemia alters repolarisation and it prolongs thesQT interval =-=[10]-=-. The extent of QT prolongation during ansacute coronary artery occlusion depends on the degree ofscollateralisation [10, 11]. Intriguingly, there is increasingsevidence that the collateral circulatio...

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...epolarisations.sThe clinical usefulness of these tests is controversial. Theshighest diagnostic yield may be a combination of tests givensthe limited predictive value of each individual investigations=-=[15]-=-.s1875-6557/13 $58.00+.00 © 2013 Bentham Science PublisherssOut-of-Hospital Cardiac Arrest –Optimal ManagementsCurrent Cardiology Reviews, 2013, Vol. 9, No. 4s317sTHE RISK OF SCD IN ATHLETESsOverall, ...

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... care is to optimize cardiocerebral recovery. In-hospital aims include maintaining cardiac output and cerebral perfusion, optimising systemicshaemodynamics and minimising ischaemia-reperfusion injury =-=[26]-=-. The importance of optimal post-resuscitation caresis highlighted in the recent 2010 International Liaison Committee on Resuscitation (ILCOR) Consensus on CPR Science with Treatment Recommendations (...

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...l post-resuscitation caresis highlighted in the recent 2010 International Liaison Committee on Resuscitation (ILCOR) Consensus on CPR Science with Treatment Recommendations (CoSTR) and ERCsGuidelines =-=[27, 28]-=-. Table 2 gives an overview of a recommended diagnostic work-up of patients who survived SCA.sMANAGEMENT OF OHCAsAn updated Advanced Life Support (ALS) algorithm forsmedical professionals is shown in ...

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...ulation (ROSC) at the scene andswho are suspected to have obstructive CAD may benefitsfrom PCI whilst receiving continuous CPR [34]. Importantly, PCI plays a major role in the improved survivalsrates =-=[35, 36]-=-. In a study of 714 OHCA patients referred tosa tertiary centre in Paris, 435 (61%) had no obvious extracardiac cause. This subgroup underwent early coronarysangiography and 70% of those had at least ...

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..., just 48% of thes2289 enrolled patients admitted hospital were treated withstherapeutic hypothermia [48]. On the other hand, in the UKs86% of intensive care units had implemented hypothermiasby 2009 =-=[49]-=-. Lack of resources and cost of MTH are commonly cited as barriers to implementation, despite relativelyscheap options being available.sHowever, in patients with MTH several side effects maysoccur. MT...

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...es. The main cause ofsdeath in these trials was low cardiac output due to progressive heart failure (45-50%), severe arrhythmia (20-35%) andsnon-cardiac related death (e.g. renal disease, ca. 20-30%)s=-=[55, 56]-=-. Table 3. refers to the European Society of Cardiology (ESC) guidelines on decision making on implantablescardioverter defibrillator (ICD) implantation for secondarysprevention of SCA due to severe a...

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..., “S-100” or “IL-8”, although predictive value and accuracy varies widely in different studies [67, 68]. More precise tools to predict outcomesswould help tremendously for optimal resource allocations=-=[69]-=-.sCARDIAC ARREST CENTRESsThere is variation in outcome for OHCA patients depending on the hospital they are admitted to [70] and there isssome evidence that mortality is lower among those admittedsto ...

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...d. Wesknow that ischemia alters repolarisation and it prolongs thesQT interval [10]. The extent of QT prolongation during ansacute coronary artery occlusion depends on the degree ofscollateralisation =-=[10, 11]-=-. Intriguingly, there is increasingsevidence that the collateral circulation has a protective rolesduring early ischemia. A study in 170 patients with acutesanterior infarction showed lower incidence ...

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...chest compressions (“hands-only cardio- pulmonary resuscitations(CPR) without ventilation, might not entail adverse consequences on neurologic outcome, at least within the first fewsminutes after SCA =-=[22]-=-.sHowever, the debate on the ratio of chest compressionssand ventilations during CPR and the continuous adaption ofsguidelines may have confused lay people and preventedsthem from performing CPR. Nose...

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...uidelines advocate immediate defibrillation, both approaches seem to have comparable results and in patientsswith a cardiac arrest >5 minutes, chest compressions beforesdefibrillation may be superior =-=[23]-=-.sTable 1. Causes of OHCA [5-7]sCardiac causessNon-cardiac causes (≈5-12%)sIschemia (≈70%)s•scoronary artery disease (CAD)s•sheart failures•snot related to CAD:s- coronary embolis- inflammatory diseas...

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...e maintained during transport [24]. However, there is currently insufficient evidence for a clear advantage over manual chest compressions with regard tosclinical outcomes when using the LUCAS device =-=[25]-=-. Similarly, the Circulation Improving Resuscitation Care (CIRC)strial assessing the effect of the AutoPulse automatic chestscompression device in >4000 OHCA patients failed to showsa survival benefit...

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...ulation (ROSC) at the scene andswho are suspected to have obstructive CAD may benefitsfrom PCI whilst receiving continuous CPR [34]. Importantly, PCI plays a major role in the improved survivalsrates =-=[35, 36]-=-. In a study of 714 OHCA patients referred tosa tertiary centre in Paris, 435 (61%) had no obvious extracardiac cause. This subgroup underwent early coronarysangiography and 70% of those had at least ...

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...ooled to 32°C to 34°C for at least 12 to 24 hours. MTH cansalso be considered following OHCA with non-shockablesinitial rhythms such as PEA or asystole but the benefit insthese patients is less clear =-=[28, 41]-=-.sMany questions surrounding MTH remain unanswered.sThe timing of initiation and the optimal duration of coolingsare unclear. Should MTH be initiated pre-hospital or is itssufficient to start this the...

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... are inexpensive, but initial coolingsmay be slower [45]. One study has shown that both intravascular and surface cooling are equivalent in their effectiveness to reach and maintain core temperatures =-=[46]-=-,salthough another showed better temperature control with ansintravascular device [47]. Whichever method is used, asfeedback loop is advocated to ensure target temperaturescompliance and to prevent ov...

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...h intravascular and surface cooling are equivalent in their effectiveness to reach and maintain core temperatures [46],salthough another showed better temperature control with ansintravascular device =-=[47]-=-. Whichever method is used, asfeedback loop is advocated to ensure target temperaturescompliance and to prevent overcooling. Devices with feedback control also enable better control of rewarming (usua...

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... heart failure management will be mandatory in this patient population [59].sPROGNOSIS AFTER SCAsThe Time to defibrillation and other factors such as bystander CPR, has not improved over precise time =-=[60]-=-. Theschain of survival (Fig. 2) is changing over time and it isslikely that it will soon include pre-hospital induction of hypothermia and early coronary intervention. Overall, suchschanges have incr...

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...estimatesthe impact of hypoxic brain injury, such as the levels of thesprotein “neurone specific enolase”, “S-100” or “IL-8”, although predictive value and accuracy varies widely in different studies =-=[67, 68]-=-. More precise tools to predict outcomesswould help tremendously for optimal resource allocations[69].sCARDIAC ARREST CENTRESsThere is variation in outcome for OHCA patients depending on the hospital ...