运动员猝死的发生和预防

运动员在训练或比赛时发生心脏性猝死,虽不常见,但影响很大;2008年北京奥运会即将举行,我们关注运动员的安全,预防运动员猝死的发生是非常必要的。     

Prevention of Sudden Cardiac Death

Although the annual incidence of sudden cardiac death (SCD) is dropping in the United States, therapies for the patient who has survived a SCD episode or is at high risk of developing SCD in the future are now well established. The implantable cardioverter defibrillator (ICD) has emerged from a series of well done randomized clinical trials of the 1990s as providing a survival benefit in carefully defined patient groups with low ejection fraction of any cause. Patients with either an ischemic or idiopathic dilated cardiomyopathy and an EF ≤35% show a significant survival benefit with the ICD and maximal medical therapy. Many challenging patients (e.g., those with long QT syndrome or Brugada syndrome) who have a reasonably high incidence of sudden death have not been the subject of clinical trials involving the ICD and therapy depends on risk stratification that is currently not completely agreed upon. An exciting research frontier of the future will be those that attempt to integrate the appropriate role of the ICD with the ability of chronic resynchronization therapy to enhance left ventricular function in the damaged ventricle.     

Sudden Cardiac Death in Young Adult

Cardiovascular disease represents one of the most important public health problem in the Western countries, with sudden cardiac death (SCD) being the most common cause of death in adults under 65 years of age. The objective of the present study is to evaluate the leading causes of SCD in young adults who died suddenly in Northern Portugal between 2007 and 2012. This study included 288 cases of 20- to 45-year-old adults who died suddenly of a cardiac cause and whose forensic autopsy was performed in the North Branch of the National Institute of Legal Medicine and Forensic Sciences between 2007 and 2012. Data included the cause of death, forensic autopsy findings, previous medical history and cardiovascular risk factors. The mean age of the population was 37.36 years. Coronary artery disease (CAD) was the leading cause of death, representing 55.6 % of all cases (92.5 % of men and 7.5 % of women). Females died mostly from probable primary arrhythmia. From those who died of coronary disease, 72 (25 % of total cases) had histological evidence of a fatal acute infarction. Age, previous coronary disease, hypercholesterolemia, smoking habits and alcohol consumption seem to be associated with an increased risk of SCD by CAD. A total of 55.6 % of deaths were attributed to CAD. Prevention of cardiovascular risk factors should therefore be considered to prevent atherosclerosis in young adults.     

Canadian Cardiovascular Society Cardiovascular Screening of Competitive Athletes: The Utility of the Screening Electrocardiogram to Predict Sudden Cardiac Death

Prevention of sudden cardiac arrest/death (SCA/D) among athletes is a universal goal, although the optimal strategy for its achievement is controversial, with the inclusion of the 12-lead electrocardiogram (ECG) at the center of the debate. The ECG exhibits superior sensitivity over history and physical examination to detect conditions associated with SCA/D. However, the identification of disease does not necessarily lead to a significant reduction in SCA/D. The “Canadian Cardiovascular Society/Canadian Heart Rhythm Society Joint Position Statement on the Cardiovascular Screening of Competitive Athletes” recommended against the routine performance of an ECG for the initial cardiovascular screening of competitive athletes. The incidence of SCA/D among athletes (<35 years of age), the risk of SCA/D during sport participation among individuals with abnormalities found on screening ECG, the efficacy of the ECG to identify conditions associated with SCA/D, and the positive predictive value of an abnormal ECG to predict SCA/D are critically examined. This review presents the evidence informing the panel’s recommendation.     

Risk Stratification for Prevention of Sudden Cardiac Death

Sudden cardiac death (SCD) is a very prevalent cause of death in the United States. The majority of individuals who experience SCD do not survive the episode. Although there are ongoing efforts to improve resuscitation (ie, training in cardiopulmonary resuscitation, easy access to automatic external defibrillators), the primary modality addressing this public health problem is prevention by identification and treatment of high-risk cohorts. Current screening techniques have focused on identifying patients for primary prevention of ventricular tachyarrhythmias. Primary prevention therapies include medications, such as beta-blockers, statins, and angiotensin-converting enzyme inhibitors, and the implantable cardioverter defibrillator (ICD), whose use is currently focused on only the highest-risk subpopulations. The high-risk groups that are currently screened for consideration of an ICD for either primary or secondary prevention of SCD include those with a variety of cardiomyopathies, those with a history of previous aborted SCD, and those with genetic predispositions. In patients with ischemic cardiomyopathy and nonischemic dilated cardiomyopathy, the primary screening parameter to identify the highest-risk group (which is then subsequently screened for consideration of an ICD) is left ventricular ejection fraction (LVEF). Various other clinical factors and noninvasive test results are often combined with this information, but the optimal way in which this should be done has not been established. The array of noninvasive tests available includes those focusing on depolarization abnormalities, repolarization abnormalities, disturbed autonomic responses, and imaging. Unfortunately, current risk-stratification paradigms do not identify the majority of patients who will experience SCD. The fundamental reason for this is that the risk of SCD is truly lower in those without high-risk features such as depressed LVEF; however, the much larger number of patients with these lower-risk features translates into a larger absolute number of SCDs in this lower-risk group. In order to widen the scope of risk stratification, careful clinical study will be needed to develop appropriate testing strategies that can reliably identify patients at significant risk for ventricular tachyarrhythmias in the broader population.     

心衰患者心源性猝死的一级预防

心衰患者SCD平均发生率约40％。 本文综述SCD发生率、原因、高危病人的识别及药物治疗对SCD的影响。并且概述ICD在SCD一级预防中的重要性。     

Aspirin to Prevent Sudden Cardiac Death in Athletes with High Coronary Artery Calcium Scores

While proficient cardiac resuscitation has improved survival following cardiac arrest during road races in Japan, this accomplishment does not address coronary artery disease as the underlying cause of an increasing frequency of cardiac arrest in middle-aged men during marathons and ironman triathlons in the United States since the year 2000. Based on the high prevalence of subclinical coronary artery disease by cardiac computed tomography in endurance athletes with low conventional cardiac risk-factor profiles, we recommend coronary artery calcium scores as a more reliable and independent predictor of incident cardiac events, including death, as validated among adults aged 30-46 years. Scores of over 100 Agatston units indicate a 10-year cardiac risk of 7.5%, at which additional measures for primary prevention are recommended, including aspirin, as shown conclusively to reduce first myocardial infarctions in same-aged men in a prospective double-blind controlled trial. Targeted screening for subclinical coronary atherosclerosis with coronary artery calcium scores is prudent to guide appropriately dosed aspirin use to mitigate the increasing frequency of sports-related sudden cardiac death due to plaque rupture.     

Use of Nonantiarrhythmic Drugs for Prevention of Sudden Cardiac Death

It is of interest that the drugs having the most significant impact on total and sudden death mortality are those without direct electrophysiologic actions on myocardial excitable tissue. This observation may provide insight into mechanisms responsible for ventricular tachyarrhythmias causing cardiac arrest. One way to think about ventricular fibrillation is that it is the final common pathway of an electrically unstable heart. After all, the heart can "die" in only three major ways: electromechanical dissociation, asystole and heart block, and ventricular fibrillation, with the latter most common. It is the "upstream" events provoking the electrical instability that these drugs probably act upon (i.e., ischemia, fibrosis). Although we unquestionably need to pursue investigations into the electrophysiology of these ventricular tachyarrhythmias, more studies need to investigate the drugs affecting upstream events, because these agents appear to yield the greatest dividends, at least for the present. This article reviews these drugs and how they may be effective. (J Cardiovasc Electrophysiol, Vol. 14, pp. S87-S95, September 2003, Suppl.)     

心力衰竭患者心源性猝死的预警和治疗策略

重点探讨心力衰竭患者发生心源性猝死的预测方法和治疗策略,旨在为心源性猝死的预防及治疗提供客观依据。