ABC | Volume 112, Nº3, March 2019

Updated The Brazilian Society of Cardiology and Brazilian Society of Exercise and Sports Medicine Updated Guidelines for Sports and Exercise Cardiology - 2019 Arq Bras Cardiol. 2019; 112(3):326-368 to vary according to menstrual cycle and postmenopausal hormone replacement. 275 Unlike men, ST-segment change in asymptomatic women does not correlate with mortality. In many circumstances, due to the relatively higher prevalence of false-positive traits in women, those with ST-segment depression generally receive non-cardiac diagnoses, with no additional exams or subsequent cardiac treatment. 276 In men and women, a chronotropic index < 0.8 and HR recovery < 12 bpm after the first minute correlate with increased mortality and are valuable measures for prognostic evaluation. Functional capacity, obtained though the exercise stress testing, is especially useful for athletes, besides being an independent predictor of CAD and mortality. For accurate evaluation of exercise capacity, as well as for training adjustments, an association of exercise ECG and expired gas measurements (CPET) is recommended. 259 Recommendation Recommendation grade Evidence level Exercise stress testing in initial assessment for competition or a series of tests for training load adjustment IIb B CPET (previous item) IIa B CPET: cardiopulmonary exercise testing. 7.5. Sudden Death Curiously, the occurrence of SD differs between male and female athletes. Several types of evidence indicate that SD is overwhelmingly more prevalent in male athletes. 277-280 This disproportional occurrence would seem to suggest that women have some “protective factor” against heart disease, in whom SD is less likely than men under similar conditions. However, little is known about other factors that could be decisive in this outcome. Moreover, it has been shown that 92% of young athletes with SD were men, and that only 53% of women had some structural change. 281 The proportion of women among master athletes (> 40 years of age) has grown. There has been much discussion about whether intense exercise over a period of many years has deleterious effects. Myocardial fibrosis, atherosclerotic plaques, and a higher incidence of atrial fibrillation have been found in some groups of athletes. 282 However, whether the additional risk from very intense exercise applies equally to men and women has also been questioned. A recent meta- analysis involving more than 149,000 women 283 found that moderate exercise reduces the chance of developing atrial fibrillation, especially in comparison to sedentary women, and that women who exercised intensely on a regular basis had a 28% lower risk of atrial fibrillation. In contrast, a prospective study suggested that the risk of atrial fibrillation in women followed the same pattern as in men. 284 According to this study, the risk in more active women was higher than in moderately active women and similar to that of sedentary women. Thus, further investigation is necessary to better understand the relationship between exercise and atrial fibrillation in women. 8. Basic Life Support for Athletes 8.1. Sudden Death among Athletes Although rare, SD at a sporting event causes a public commotion, especially when involving elite athletes. Statistics show that in the general population the incidence of SD during exercise is approximately 0.46 cases per 100,000 person- years. 285 In young athletes this incidence is also low: (a) 0.5 for every 100,000 person-years among athletes in Minnesota; (b) 2.3 per 100,000 person-years among competitive athletes in northern Italy; 7 (c) 1 to 3 for every 100,000 person-years in professional American football players. 286 However, the true incidence of cardiac SD in athletes still requires further investigation. More recently, Emery and Kovacs 144 pointed out that the studies estimating these events vary methodologically, diverging between the number of athletes who suffered SD (numerator) and the number of athletes at risk (denominator). In addition, some included only events that resulted in death, while others also included those who survived cardiorespiratory arrest. Several structural and non- structural changes (channelopathies) are responsible for most cases of cardiac arrest among athletes. Studies conducted in the 1990s pointed to HCM as the main cause of SD, 287,288 and data from another experiment conclusively showed that HCM is the main cause of SD in young athletes, accounting for 26% of cases. 289 Nevertheless, a meta-analysis of retrospective cohort studies, registries, and autopsy series by Ullal et al. 290 challenged these conclusions: in more than 4,000 young SD victims, structurally normal hearts were the most common findings (26.7%). Interestingly, the proportion of HCM was much lower among their sample (10.3%). Irrespective of these controversies, however, vigorous exercise, when associated with heart disease, appears to trigger malignant events. PPS generally consists of a detailed history, a physical examination and resting 12-lead ECG, although whether ECG should be mandatory has been debated in the international scientific community. 5 An important Italian study showed that mandatory ECG use reduced the annual incidence of cardiac SD by 90%. 291 The American Heart Association/American College of Cardiology question the cost-effectiveness of this strategy, the high rate of false-positive results, and the availability of qualified personnel to interpret the results. 292 On the other hand, the European Society of Cardiology recommends ECG for PPS. 35 Regardless of this controversy, PPS cannot eliminate SD among athletes. Thus, a second pillar must be further developed: basic life support. 8.2. Initial Care for Athletes The basic emergency care strategy can be summarized as a set of actions taken in the first few minutes following a sudden cardiac event: (1) the organization and planning of an emergency response team at the activity site; (2) training first responders in cardiopulmonary resuscitation and AED use. Places where sports activities occur (e.g., training centers, schools, colleges, gymnasiums, etc.) must have a well-organized emergency care plan, including personnel trained in basic life support and fast and effective 355