Frequency Of Sudden Cardiac Death Research Articles

Postmortem Immunohistochemical Findings in Early Acute Myocardial Infarction: A Systematic Review.

The diagnosis of early acute myocardial infarction is of particular importance in forensic practice considering the frequency of sudden cardiac death and the difficulty of positively identifying it through classical histological methods if survival is less than 6 h. This article aims to analyze potential immunohistochemical markers that could be useful in diagnosing acute myocardial infarction within the first 6 h of its onset. We conducted an extensive evaluation of the literature according to the PRISMA guidelines for reporting systematic literature reviews. We searched the Web of Science and PubMed databases from their inception to 2023 using the following keywords: "myocardial infarction" and "immunohistochemistry". Fifteen studies met the inclusion criteria. Immunohistochemical markers as complement factors and CD59, myoglobin, fibrinogen, desmin, tumor necrosis factor alpha (TNF-α), P-38, JNK (Jun N Terminal Kinase), transforming growth factor β1 (TGF-β1), cardiac troponins, fibronectin, H-FABP (heart fatty acid binding protein), dityrosine, fibronectin, CD15, IL-1β, IL-6, IL-15, IL-8, MCP-1, ICAM-1, CD18, and tryptase can be used to identify the first six hours of acute myocardial infarction. These markers are mostly studied in experimental animal models. It is necessary to conduct extensive studies on human myocardial tissue fragments, which will involve the analysis of several immunohistochemical markers and careful analysis of the available data on perimortem events, resuscitation, and postmortem intervals in the context of a uniform laboratory methodology.

Long <i>QT</i> Syndrome in Young Athletes

Long QT syndrome is a disease associated with a high risk of sudden cardiac (arrhythmic) death. The frequency of sudden cardiac death is approximately 1: 100,000 young athletes, while autopsies often do not detect changes, which indicates a primary arrhythmogenic death. The article describes two clinical cases of young athletes with prolongation of the QT interval. The possible causes of the long QT syndrome and the difficulties of diagnosing this syndrome in children and adolescents involved in sports are discussed. Regardless of the reasons leading to the prolongation of the QT interval, there is a risk of arrhythmic events. Timely diagnosis of long QT syndrome is the way to the primary prevention of sudden cardiac death in young athletes.

<I>PRKAG2</I>-associated hypertrophic cardiomyopathy

Mutations in the PRKAG2 gene lead to hypertrophic cardiomyopathy in combination with Wolff—Parkinson—White syndrome. The cause of the development of heart damage is the deposition of glycogen in the myocardium and the conduction system of the heart with a violation of the metabolism of adenosine monophosphate-activated protein kinase. A feature of PRKAG2 hypertrophic cardiomyopathy is progressive conduction disturbances with the development of atrioventricular blockade and ventricular preexcitation syndrome with a high frequency of paroxysmal supraventricular tachycardia against the background of additional atrioventricular fenestrations (Wolff—Parkinson—White syndrome). Progressive heart failure, high frequency of sudden cardiac death at a young age are characteristic. The features of diagnosis and treatment are considered.

Abstract 10541: Clinical Risk Factors and Myocardial Fibrosis in Subjects Who Died Suddenly: Pilot Data from A 10-Year Post-Mortem Data Registry

Introduction: Sudden cardiac death (SCD) is responsible for approximately 380,000 deaths per year. One third of the patients dying of heart disease present with SCD as the first manifestation. There are limited data on the clinico-pathological determinants of SCD. Hypothesis: We hypothesized that, compared to overall deaths, silent coronary atherosclerosis and myocardial fibrosis could be associated with increased frequency of SCDs. Methods: We reviewed the post-mortem data registry from two tertiary care hospitals located at the Buffalo-Niagara Region. Of the 1,314 subjects that underwent comprehensive post-mortem analysis, we identified 187 subjects that died suddenly. For this initial pilot data analysis protocol, we compared the demographic, clinical, electrocardiographic and coronary vascular and myocardial histopathological characteristics of 109 subjects with sudden death vs. 34 age-matched controls with non-sudden death. Results: We found that, of the total 1,314 subjects screened, 14% had SCD. Comparison of age-matched SCD with non-SCD subjects (age in years, SCD: 60±14; non-SCD: 61±20) showed that SCD groups had larger cardiac size (heart weight in grams, SCD: 550±150; non-SCD: 480±117, P=0.03), increased wall thickness (posterior wall thickness in cm, SCD: 1.7±0.4; non-SCD: 1.5±0.2, P=0.01), but reduced LV function reported before the event (LV ejection fraction in %, SCD: 41±17; non-SCD: 58±9, P=0.007). In addition, SCD groups had higher frequency of coronary atherosclerosis (SCD, 76% vs., non-SCD, 52%, P=0.007), and myocardial fibrosis involving both left ventricular free wall (SCD, 47% vs., non-SCD, 26%, P=0.03), and interventricular septum (SCD, 29% vs., non-SCD, 3%, P=0.02). There were no differences on serum electrolytes, circulating biomarkers and the extent of right ventricular fibrosis. Conclusions: The subjects that died suddenly had larger cardiac size, reduced contractile function with myocardial interstitial fibrosis, and silent coronary atherosclerosis. Further studies are in progress to fully examine the clinico-pathological correlates of SCD in our longitudinal study cohorts.

Apical hypertrophic cardiomyopathy: A case series at a Brazilian referral center with a maximal follow-up of 15 years

BackgroundApical hypertrophic cardiomyopathy (AHCM) is a rare cardiomyopathy, in which hypertrophy occurs predominantly in the ventricular apex, and in some cases with a high risk of sudden cardiac death. ObjectiveThe aim of this paper is to present a case series of patients with AHCM and describe their main clinical, echocardiographic and electrocardiographic characteristics, the recommendation for an implantable cardioverter-defibrillator (ICD) and the frequency of sudden cardiac death (SCD). MethodsA retrospective case series was conducted at the referral center of a federal teaching hospital, between the years 2005 to 2020, involving patients with an echocardiographic diagnosis of AHCM. The parameters of the American College of Cardiology and the European Society of Cardiology were used to assess the risk of SCD. ResultsA total of 11 individuals were assessed with a mean age of 55.3 years, mean follow-up of 41.2 months, most of whom were symptomatic at diagnosis (72.7%). The most frequent symptom was dyspnea (27.3%). A family history of SCD was described in 45.5% of cases. Due to a high risk of SCD, four patients received ICDs. One patient presented sudden cardiac death after having refused the ICD. ConclusionsSymptoms and alterations in the imaging exams are significant factors in the clinical and prognostic assessment of patients with AHCM.

К вопросу о внезапной сердечной смерти у спортсменов: анализ литературы за 2016 год

Sudden cardiac death (SCD) in athletes isn't a frequent event, but, nevertheless, deserves a lot of attention from both the scientific community and health care professionals, coaches and athletes. The literature review showed that the problem of SCD still remains relevant because of its close association with physical activity and the lack of united standards of its screening, diagnostic and prevention. It is shown that the frequency of SCD varies widely depending on the population of the athlete, age and genetic characteristics, controversial is the question of the necessity and scope of a standard pre-season screening.

NEUROTROPIC MYOCARDIAL SCINTIGRAPHY IN THE EVALUATION OF SUDDEN CARDIAC DEATH PROGNOSIS IN PATIENTS WITH HYPERTROPHIC CARDIOMYOPATHY

Objective . To explore the features of cardiac sympathetic activity impairments using neurotropic scintigraphy and singlephoton emission tomography (SPECT) in patients with hypertrophic cardiomyopathy (HCM), including the context of the risk of sudden cardiac death (SCD). Material and methods. 36 patients with HCM, II–IV NYHA CHF grade, underwent cardiac neurotropic scintigraphy and SPECT with 123I-MIBG. 30 patients also underwent cardiac perfusion SPECT with 99mTc-MIBI, standard quantitative parameters of global and local left ventricular sympathetic activity and perfusion impairments were obtained. After 5 years of follow-up, the analysis of the dependence of the frequency of SCD in patients with HCM on the values of the above parameters was performed. Results. All parameters of perfusion and neurotropic myocardial SPECT were significantly different in patients with HCM compared with the control group (p 4) in the main group was detected in 32% of cases, while it had a diffuse character and had no connection with certain coronary artery regions. The volume of regional innervation defects (SMSe) in HCM patients significantly exceeded the total volume of perfusion defects (SSS, p 14 predicted the occurrence of SCD with sensitivity of 87.5% and specificity of 57.1%. The risk of five-year mortality from SCD was significantly higher when SMSe >14 (p=0.024). Conclusion. Neurotropic SPECT in patients with HCM is able to identify a group of patients at high risk of sudden cardiac death.

Sudden Cardiac Deaths in a Metropolitan City of South India: A Prospective Study

Many cases of sudden unexpected natural deaths occur in individuals without known medical diseases. Among them sudden cardiac death (SCD) remains an important worldwide public health problem. The epidemiology of SCD in India continues to be understudied. In this prospective an autopsy series was conducted at KIMS hospital Bangalore and various parameters were analysed, such as the frequency of SCDs among the autopsies conducted, the demographic profile and the causes for SCDs. Out of 760 autopsied victims during an 18-month study period, 88 cases were of sudden natural deaths. Among them 60 cases of sudden natural deaths were selected for the study based on purposive sampling. Among the 60 cases of sudden natural deaths, 38 cases (63.3%) were due to SCD. Maximum number of victims (47.3%) observed were in the age group of 41–50 years. Males constituted 92.1% of the total victims. Maximum cases were observed in the middle-class society (47.3%). Majority of the victims (78.9%) were from urban areas. Majority of the victims (73.6%) had a mixed diet. All the victims were habituated to smoking and alcoholism (50%) each. 39.57% of the study population were hypertensive and 31.57% were diabetics. Maximum number of victims (47.36%) succumbed to death within 6–12 hours of onset of terminal symptoms. Majority of the victims (63.15%) died due to occlusive coronary artery disease.

The influence of alcohol consumption on the chronological patterns of sudden cardiac death

The objective of the present study was the retrospective analysis of the materials collected by the Republican Bureau of Forensic Medical Expertise, Ministry of Health and Social Development of Chuvash Republic, during the period from 1997 till 2002 for the elucidation of the chronological patterns of sudden cardiac death (SCD) associated with alcohol consumption depending on the sex and age of the victims, days of the week and months of the year as well as weather conditions. It was shown that the peak of mortality among men and women taking no alcohol fell on Monday. It was highest in May and decreased by February. The alcohol consumption significantly changes the chronological patterns of mortality from cardiovascular pathology. It was highest among the women abusing alcohol in August and October. The study has demonstrated a weak negative correlation between the frequency of sudden cardiac death among non-consumers of alcohol and dew-point temperature among the persons having alcohol in blood.

Novel imaging of coronary artery anomalies to assess their prevalence, the causes of clinical symptoms, and the risk of sudden cardiac death.

In a fundamental 1974 article, Cheitlin et al1 of the Armed Forces Institute of Pathology emphasized the special role of anomalous aortic origin of the coronary arteries and differentiated this condition from the other coronary artery anomalies (CAAs) as being associated with an increased frequency of sudden cardiac death (SCD) in young persons, especially during strenuous exertion. More recently, CAAs have also been considered possible causes of clinically disabling symptoms, including dyspnea, angina pectoris, and syncope, especially in young adults.2–5 Clinicians and epidemiologists have identified the need to prevent not only SCD in young persons, especially athletes or military recruits, but also other CAA-related symptoms in persons of any age.6–12 Much of the available information concerning the incidence of SCD in carriers of CAAs is lacking a denominator (measure of the carriers at risk). The most notable study of SCD incidence is a classic 2004 article by Eckart et al,7 who reported the mortality rate (>25 years) that US military recruits experienced during a 2-month-long boot-camp training period. All the recruits were involved in strenuous exercise and had undergone routine screening based on a history and physical examination performed by general practitioners. Of the 23 million recruits, 64 died of SCD (0.28 per 100 000 per 2 months, or 1.68 per 100 000 per year). Of these deaths, 21 (33%) were attributed to CAAs, specifically anomalous origin of the left coronary artery from the right sinus of Valsalva with an interarterial course. To establish a solid theory and a preventive policy in this field, we must understand the pathophysiology of CAAs, identify the prevalence of individuals living with different kinds of CAAs (the denominator), clarify the individual severity of each case, study the influence of different types of exertion, and identify the …

Seasonal variation in the frequency of sudden cardiac death and ventricular tachyarrhythmia in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy: The effect of meteorological factors

Sudden cardiac death (SCD) is the most catastrophic presentation in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C). To investigate the seasonal variations in the frequency of SCD and ventricular tachyarrhythmia in patients with AVRD/C and to elucidate the meteorological factors that trigger these events. From 1998 to 2012, we enrolled 88 consecutive patients with ARVD/C from Taipei City. The cohort included 20 living patients who received implantable cardioverter-defibrillator (ICD) and 68 autopsied patients with SCD from the Taiwan National Forensic Institute registry. The baseline clinical characteristics, seasonal distribution, and associated meteorological factors were explored to predict the occurrences of events, which include appropriate ICD interventions and SCD. There were 106 events, including 38 (35.8%, 1.9 episodes per patient) appropriate ICD interventions in living patients with ARVD/C and 68 (64.2%) SCD events. The seasonal peak occurred predominantly in summer (P < .05) in both groups. For meteorological factors, the onset of event was associated with higher average daily temperature and longer sunshine duration. The variation in humidity within 3 days of events was significantly increased. After multivariate logistic regression analysis, higher average daily temperature and larger variation in humidity were associated with increase in events (odds ratio 1.23, 95% confidence interval 1.16-1.31, P < .001, and odds ratio 1.19, 95% confidence interval 1.15-1.23, P < .001, respectively). There was seasonal variation with a summer peak in the occurrence of ventricular arrhythmias and SCD in patients with ARVD/C. Meteorological factors including higher temperature and larger variation in humidity within 3 days of events were independently associated with the development of events.

Prediction and prevention of sudden death in young populations: the role of ECG screening

Sudden cardiac death (SCD), particularly when it affects a child or a young athlete who is presumed to be healthy, is an emotionally charged event that has a widespread impact. An effective ECG screening strategy for this population is intuitively appealing. The primary objective of ECG screening is to detect occult cardiovascular conditions likely to manifest with SCD. Such an endeavor is only effective if it is highly sensitive with an acceptably low false-positive rate. It also must be accompanied by an intervention that reduces the risk of SCD and improves outcomes. Despite significant advancements, considerable knowledge gaps remain about the etiology of SCD and the frequency with which SCD occurs. Reports of screening programs that have reduced the incidence of SCD have limited generalizability based on program design and the populations studied. Within the USA, considerable gaps in knowledge exist related to the frequency of SCD in youth and to the incremental predictive value of an ECG when added to a standardized history and physical examination. The strategy of ECG screening of young populations needs careful consideration based on principles of effective screening and evidence-based medicine. From a health policy perspective, additional data are needed from robust registries and carefully designed trials before advancing ECG screening in youth.

Sudden cardiac death: An 11-year postmortem analysis in the region of Epirus, Greece

The aim of the study was to determine the rate of sudden cardiac death in people aged between 1 and 80 years, and to investigate its etiology. All autopsies performed during an 11-year period were reviewed. Circumstances of death, individual's information, and post-mortem findings were determined. Among 1254 sudden death autopsies performed during the study period, 688 cases were recognized as sudden cardiac death (79.8% males). The estimated annual frequency of sudden cardiac death in the region of Epirus was 18.6/100,000. The major cause of death was ischemic heart disease (82%), and in 2.6%, death was unexplained. Among our study's total population, 4.1% were <35 years old. The estimated annual rate of sudden cardiac death in the population 1–35 years old was 1.78/100,000. The most common etiology in that age group was atherosclerosis (17.8%), myocarditis (10.7%), and cardiomyopathies (10.7%), whereas 39.3% exhibited structurally normal heart. Although ischemic heart disease accounts for most of sudden cardiac death episodes, many other causes contribute. Most sudden deaths in the young were “unascertained”. The likely cause of death in these cases might be a primary arrhythmogenic disorder. Correct identification of such cases at autopsy will enable an appropriate clinical screening of surviving relatives.

Sudden cardiac death and acute drunken state: Autopsy study

Sudden natural death occurs unexpectedly in apparently healthy subjects, or in persons during an apparent benign phase in the course of disease. The most common cause is sudden cardiac death, which is sometimes the first and last manifestation of coronary heart disease. Alcohol directly influences excitation of myocytes, and therefore provokes arrhythmias and possibly, sudden cardiac death. To establish the frequency of sudden cardiac death in cases of acute alcohol intoxication, to determine blood alcohol concentration at the moment of death, and to determine frequency and level of ethanol intoxication in chronic alcohol abusers, as well as causes of sudden death in those cases. Retrospective autopsy study was performed for a three-year-period. We analyzed cases of sudden natural death, in relation to age and gender, cause of death, and blood alcohol concentration (at least 0.5 g/L). We considered the person to be a chronic alcoholic abuser if gross examination of organs during autopsy showed changes typical for excessive and habitual alcohol consumption. Our sample consisted of 997 cases: 720 men and 277 women, average age 62.0 +/- 15.2 years (min = 11; max = 98). Total of 753 of them died of sudden cardiac death: much more men (chi2 = 167.364; p = 0.000), significantly younger than women (t = 6.203; p = 0.000). We determined acute alcohol intoxication in 73 persons--average blood alcohol concentration 1.85 +/- 1.01 g/L (min = 0.55; max = 3.85), and 61 of them died of cardiovascular diseases (chi2 = 236.781; df = 5; p = 0.000). In our observed sample, not many persons were under acute alcohol intoxication (around 7%). Most commonly, they were chronic alcohol abusers who died due to exacerbation of chronic heart disease, mildly or moderately intoxicated--the younger, the drunker.

Cardiovascular Disease in Women—Challenges Deserving a Comprehensive Translational Approach

Heart disease in women is associated with high levels of morbidity and mortality. Although many of the underlying causes are similar for both genders, cardiovascular disease among women has some unique features, including higher coronary heart disease mortality, higher frequency of sudden cardiac death without previous symptoms, and increased mortality among older women compared to men following a myocardial infarction. During recent years, increasing efforts have been placed on identifying preventive measures, but translation of knowledge from epidemiological studies and clinical trials remain incomplete, particularly in women. The recent launch of the National Institutes of Health’s Clinical and Translational Science Award program offers opportunities to address these gaps and represent a unique opportunity to foster a new generation of researchers familiar with important issues regarding women’s cardiovascular health.

The association of sudden cardiac death with inflammation and other traditional risk factors

Despite the frequency of cardiovascular death in dialysis patients, few studies have prospectively measured sudden cardiac death in these individuals. Here, we sought to determine the frequency of sudden cardiac death and its association with inflammation and other risk factors among the CHOICE (Choices for Healthy Outcomes In Caring for ESRD) cohort of 1,041 incident dialysis patients. Sudden cardiac death was defined as that occurring outside of the hospital with an underlying cardiac cause from death certificate data. Over a median 2.5 years of follow-up, 22% of all mortality in this cohort was due to sudden cardiac death. Using Cox proportional hazards, we found that the highest tertiles of high-sensitivity C-reactive protein and of IL-6 were each associated with twice the risk of sudden cardiac death compared to their lowest tertiles when adjusted for demographics, comorbidities and laboratory factors. A decrement in serum albumin was associated with a 1.35 times increased risk for sudden cardiac death in the highest compared to the lowest tertile. These findings were robust and consistent when accounting for competing risks of death from other causes. Hence, we found that sudden cardiac death is common among patients with end stage renal disease and that inflammation and malnutrition significantly increased its occurrence independent of traditional cardiovascular risk factors.

Is Sport Dangerous for Children?

Daniel De Wolf Ghent University Hospital, Department of Pediatric Cardiology, De Pintelaan 185, 9000 Gent, Belgium Tel.: +32 9332 2421; Fax: +32 9332 3856; E-mail: daniel.dewolf@ ugent.be ‘The long-term beneficial effects of regular physical training by far outweigh the acute risk for sudden death in children.’ Recently, promoting physical activity in children has received much emphasis. The medical community, but also the general population, has gained conscience that physical activity offers an important shortand long-term contribution to children’s health [1]. Even in high-risk groups, such as in children with congenital heart disease, the beneficial effects of a guided sports program have been proven [2]. Guidelines for safe participation of patients with congenital heart disease in competitive sports have been established [3]. The only real drawback to vigorously promoting exercise in all children is the constant sword of Damocles, the risk of sudden death during exercise. Although rare, every event of sudden death in an apparently healthy youngster during sports is a disaster to parents and friends, which is emphasized by the immediate and mostly spectacular media coverage, thus making a deep and frightening impression on the general public. Regularly, it is questioned as to why the thorough screening of young athletes, and especially children, is not recommended and the community calls for action. After such incidents, the amount of parents self-referred to pediatric cardiologists in order to obtain ‘complete’ reassurance that their child can safely practice sports, increases dramatically. But can we really prevent sudden death in children practicing sports? And if so, then how? And to what cost? Should we limit these efforts to those engaged in competitive sports? To answer these questions, one should be aware of the real importance of the problem. Although each sudden and unexpected death of a child is absolutely devastating to parents and the community, the real incidence appears to be low. The precise frequency of sudden cardiac death during competition or training is not known, but has been estimated to be between one per 200,000 and one per 300,000 high school and college-aged athletes per year [4]. The incidence in children below the age of 16 years participating in sports is probably even lower [5]. The most common causes of exercise-related cardiac death in individuals under 35 years of age are hypertrophic cardiomyopathy (HCM), arrhythmogenic right ventricular dysplasia (ARVD, especially in Italy), myocarditis, contusio cordis, abnormal coronary artery anatomy, toxic drugs and rhythm disturbances [6,7]. For the first two anomalies (HCM and ARVD), the incidence and mortality are lower in the pediatric population when compared with adults [6]. Although sudden deaths occur during or after exercise in these anomalies, this does not appear to be the most important trigger for sudden death in children overall [5,8].

Resuscitation in the Hospital: Circadian Variation of Cardiopulmonary Arrest

Purpose Over 25 reports have found outpatient frequency of sudden cardiac death peaks between 6 am and noon; few studies, with inconsistent results, have examined circadian variation of death in hospitalized patients. This study assesses circadian variation in cardiopulmonary arrest of in-hospital patients across patient, hospital, and event variables and its effect on survival to discharge. Methods A retrospective, single institution registry included all admissions to the Medical Center of Central Georgia in which resuscitation was attempted between January 1987 and December 2000. The registry included 4692 admissions; only the first attempt was reported. Analyses of 1-, 2-, 4-, and 8-hour intervals were performed; 1- and 4-hour intervals are presented. Results Significant circadian variation was found at 1 hour ( P = .01), but not at 4-hour intervals. Significant circadian variation was found for initial rhythms that were perfusing ( P = .03) and asystole ( P = .01). A significantly higher percentage of unwitnessed events were found as asystole during the overnight hours ( P = .002). Using simple logistic regression, time in 4-hour intervals and rhythm were each significantly related to patient survival until hospital discharge ( P = .003 and P <.0001). In multivariate analysis, only rhythm remained significant. Conclusions Circadian variation of cardiopulmonary arrest in this hospital has several temporal versions and is related to survival. Late night variation in witnessed events and rhythm suggests a delay between onset of clinical death and discovery, which contributes to poorer outcomes.

Frequency of Sudden Cardiac Death Among Acute Myocardial Infarction Survivors With Optimized Medical and Revascularization Therapy

The epidemiologic pattern of sudden cardiac death (SCD) may have changed in the modern treatment era of patients after an acute myocardial infarction (AMI). We evaluated the effect of optimized medical and revascularization therapy on the incidence of SCD after an AMI. A total of 2,130 consecutive patients (mean age 59 +/- 10 years) with an AMI from 2 European centers (Germany and Finland) was included in the study. In this population, 1,004 patients (47%) were treated with an optimized medical and revascularization strategy (defined as treatment with revascularization, beta blockers, aspirin, statins, and angiotensin-converting enzyme inhibitors). Nonoptimized treatment, defined as a lack of any optimized treatment, was received by 1,126 patients (53%). During the mean follow-up of 2.9 +/- 1.3 years, the incidence of SCD was very low among patients who received optimized treatment (1.2%, annual incidence 0.4%) compared with those who did not (3.6%, annual incidence 1.4%, p <0.01). The treatment strategy that had the greatest effect on differences in the SCD rate was revascularization therapy, with the hazard ratio of SCD being 2.1 (95% confidence interval 1.2 to 3.7, p <0.01) for SCD among nonrevascularized patients. Nonoptimized treatment was more often received by older patients, women, diabetic patients, and those with depressed left ventricular function. In conclusion, the incidence of SCD is low in the modern treatment era of patients after an AMI. Coronary revascularization seems to have a great effect on altered the epidemiologic pattern of SCD.

Management of the patient who has been resuscitated from sudden cardiac death.

CD is a 68-year-old man who had an anterior myocardial infarction 6 months ago. Evaluation at that time demonstrated an occluded left anterior descending artery, which was successfully stented with no other significant lesions. Left ventricular ejection fraction was 35%. He had no recurrent angina or heart failure symptoms. Early one morning he lost consciousness. Paramedics verified ventricular fibrillation (VF) and provided effective defibrillation within 5 minutes; spontaneous circulation returned before transfer to the hospital. Sudden cardiac death claims 300 000 to 450 000 lives a year in the United States and represents approximately 50% of all cardiac death.1–3⇓⇓ Despite recent declines in age-adjusted cardiac mortality and sudden death risk, the overall incidence has remained relatively stable as our population ages.3 Coronary heart disease is present in the majority (70% to 80%) of patients with sudden death, but cardiac arrest is the first manifestation of this underlying process in 50%.4 Resuscitation rates are very low, averaging from 1% to 3% in most major cities.2,5⇓ There are some data to suggest that focused attempts to reduce the time to effective defibrillation, with improved training of first responders or more widespread availability of automatic external defibrillators, provide some hope for the future. It is a widely held belief that the majority of sudden death events are due to ventricular tachycardia (VT) that degenerates into VF (Figure 1).6 This idea may well reflect our greater experience in observing patients with structural heart disease and prior myocardial infarction. Acute severe ischemia may cause primary polymorphic VT even in the absence of preexisting structural heart disease. Autopsy studies document acute changes in coronary morphology (such as plaque rupture, thrombus, etc) in >50% of sudden death events.7 Severe bradyarrhythmias or electromechanical dissociation probably represent an important …