How to Practice Sports Cardiology: A Cardiology Perspective.

The rigorous cardiovascular (CV) demands of sport, combined with training-related cardiac adaptations, render the athlete a truly unique CV patient and sports cardiology a truly unique discipline. Cardiologists are advised to adopt a systematic approach to the CV evaluation of athletes, taking into consideration the individual sports culture, sports-specific CV demands, CV adaptations and their appearance on cardiac testing, any existing or potential interaction of the heart with the internal and external sports environment, short- and long-term CV risks, and potential effect of performance-enhancing agents and antidoping regulations. This article outlines the systematic approach, provides a detailed example, and outlines contemporary sports cardiology core competencies.

Sports and exercise cardiology in the United States: cardiovascular specialists as members of the athlete healthcare team.

In recent years, athletic participation has more than doubled in all major demographic groups, while simultaneously, children and adults with established heart disease desire participation in sports and exercise. Despite conferring favorable long-term effects on well-being and survival, exercise can be associated with risk of adverse events in the short term. Complex individual cardiovascular (CV) demands and adaptations imposed by exercise present distinct challenges to the cardiologist asked to evaluate athletes. Here, we describe the evolution of sports and exercise cardiology as a unique discipline within the continuum of CV specialties, provide the rationale for tailoring of CV care to athletes and exercising individuals, define the role of the CV specialist within the athlete care team, and lay the foundation for the development of Sports and Exercise Cardiology in the United States. In 2011, the American College of Cardiology launched the Section of Sports and Exercise Cardiology. Membership has grown from 150 to over 4,000 members in just 2 short years, indicating marked interest from the CV community to advance the integration of sports and exercise cardiology into mainstream CV care. Although the current athlete CV care model has distinct limitations, here, we have outlined a new paradigm of care for the American athlete and exercising individual. By practicing and promoting this new paradigm, we believe we will enhance the CV care of athletes of all ages, and serve the greater athletic community and our nation as a whole, by allowing safest participation in sports and physical activity for all individuals who seek this lifestyle.

Preventing sudden cardiac death in athletes: in search of evidence-based, cost-effective screening.

Sudden cardiac death in athletes is a recurrent phenomenon at sporting events and during training. Recent studies have associated sudden cardiac death with such cardiovascular conditions as coronary artery anomalies, cardiomyopathies, and electrocardiographic abnormalities, most of which are screenable with modern imaging techniques. We recently inaugurated the Center for Coronary Artery Anomalies at the Texas Heart Institute, which is dedicated to preventing sudden cardiac death in the young and investigating coronary artery anomalies. There, we are conducting 2 cross-sectional studies intended to firmly establish and quantify, in a large group of individuals from a general population, risk factors for sudden cardiac death that arise from specific cardiovascular conditions. In a pilot screening study, we are using a brief, focused clinical questionnaire, electrocardiography, and a simplified novel cardiovascular magnetic resonance screening protocol in approximately 10,000 unselected 11- to 15-year-old children. Concurrently, we are prospectively studying the prevalence of these same conditions, their severity, and their relation to exercise and mode of death in approximately 6,500 consecutive necropsy cases referred to a large forensic center. Eventually, we hope to use our findings to develop a more efficient method of preventing sudden cardiac death in athletes. We believe that these studies will help quantify sudden cardiac death risk factors and the relevance of associated physical activities--crucial information in evaluating the feasibility and affordability of cardiovascular magnetic resonance-based screening. We discuss the rationale for and methods of this long-term endeavor, in advance of reporting the results.

Making prudent recommendations for return-to-play in adult athletes with cardiac conditions.

Clinicians who treat millions of adult athletes throughout the world may be faced with participation or return-to-play decisions in individuals with known or suspected cardiac conditions. Here we review existing published participation guidelines and analyze emerging data from ongoing registries and population-based studies pertaining to return-to-play decisions for cardiac conditions specifically affecting adult athletes. Considerations related to return-to-play decisions will vary according to age of the athlete, with inherited disorders being the main consideration in younger adult athletes aged 18 to 40 yr, and coronary artery disease being the main consideration in older adult athletes aged 40 yr and older. Although this arbitrary division is based on the epidemiology of underlying heart disease in these populations, the essential return-to-play decision process for both age groups is quite similar. Among the most widely used guidelines to make return-to-play decisions in this group of athletes are the 36th Bethesda Conference Eligibility Recommendations for Competitive Athletes with Cardiovascular Abnormalities. These have long been considered the "gold standard" for determining return-to-play decisions in young athletes in the United States. Other guidelines are available for unique purposes, including The European Society of Cardiology guidelines, and the American Heart Association published recommendations regarding participation of young patients (younger than 40 yr) with genetic cardiovascular diseases in recreational sports. The latter are consistent with the 36th Bethesda guidelines and cover common genetically based diseases such as inherited cardiomyopathies, channelopathy, and connective tissue disorders like Marfan's syndrome. The consensus on masters athletes (older than 40 yr) provides return-to-play decisions for a wide variety of conditioned states, from elite older athletes to walk-up athletes. For any adult athlete with a cardiac condition, return-to-play decisions following use of medications, ablation procedures, device implantation, corrective surgery, or coronary intervention depend on whether the procedure has sufficiently altered the risk for sudden cardiac events, and whether there is a potential for unfavorable interaction with cardiac performance.

Hypertension update and cardiovascular risk reduction in physically active individuals and athletes.

Hypertension is a prevalent disease worldwide. Its inadequate treatment leads to major cardiovascular complications, such as myocardial infarction, stroke, and heart failure. These conditions decrease life expectancy and are a substantial cost burden to health care systems. Physically active individuals and professional athletes are not risk free for developing this condition. Although the percentage of persons affected is substantially lower than the general population, these individuals still need to be thoroughly evaluated and blood pressure targets monitored to allow safe competitive sports participation. Regarding treatment, lifestyle modification measures should be routinely emphasized to athletes and active individuals with the same importance as for the general population. Medication treatment can be complicated because of restrictions by athletic organizations and possible limitations on maximal exercise performance. In addition, the choice of an antihypertensive drug should be made with consideration for salt and water losses that routinely occur in athletes, as well as preservation of exercise performance and endothelial function. First-line therapies for athletes and physically active individuals may be different from the general population. Some authorities believe that blocking the renin-angiotensin system with angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) is more beneficial compared with diuretics because of ACE inhibitors and ARBs being able to avoid salt and water losses. Dihydropyridine calcium channel blockers (CCBs) are another reasonable choice. Despite effects on heart rate, nondihydropyridine CCBs do not appear to impair exercise performance. beta-Blockers are not used as a first-line therapy in athletes because of effects on exercise and prohibition by the National Collegiate Athletic Association and World Anti-Doping Agency in certain sports. In this article, we address the evidence on hypertension and its related treatments in active individuals to provide recommendations that allow the best competitive sports results and reduce cardiovascular risk.

Return-to-play decisions in athletes with cardiac conditions.

Many sets of guidelines written by experts in their fields can assist sports medicine physicians to make return-to-play decisions for athletes with known or suspected cardiac conditions. These guidelines can be divided into pre-participation screening guidelines, such as the 2007 American Heart Association (AHA) 12-element screening examination, and specific recommendations for those with heart disease or symptoms. Several important documents fall into the latter category. Among these are the 36th Bethesda Guidelines, the European Society of Cardiology Guidelines, the AHA Consensus Document for Young People with Genetic Conditions, the Heart Rhythm Society Guidelines, and the Guidelines for Masters Athletes. Guidelines are designed to enhance the sports medicine physician's probability of detecting heart disease and making wise participation and return-to-play decisions in athletes with high-risk cardiac conditions, such as hypertrophic cardiomyopathy, anomalous coronary artery, myocarditis, and valvular heart disease. Guidelines also aid in writing exercise prescriptions for those deemed too high risk for sports participation. Because the guidelines may not be entirely consistent on all topics, or based on opinion rather than research evidence, many cases require additional input from a cardiologist or electrophysiologist. Guidelines address not only specific disease entities, but also how corrective surgery, ablations, implantable defibrillators, or drug therapy can influence return-to-play decisions. They are updated as new studies become available to provide physicians with the most up-to-date information.

Palpitations in athletes.

In an athletic population, the incidence of palpitations varies from 0.3% to as high as 70%, depending on age and type of sport being studied. Palpitations, or an awareness of an increased or abnormal heart beat, are rare in the school-age athlete, but much more common in older endurance athletes. The majority are felt to be benign, with prognosis relating to type of specific rhythm disturbance and presence or absence of underlying heart disease. Atrial fibrillation can account for up to 9% of rhythm disturbances in elite athletes, and up to 40% in those with long-standing symptoms. In athletes with premature ventricular beats (PVCs), underlying heart disease is more likely to be present in those with a high PVC burden, defined as >/=2000 PVCs/24 hours. Choice of monitoring device is crucial in making a proper diagnosis of the specific rhythm disturbance. For symptoms occurring within a 24-hour period, simple Holter monitoring is adequate to make a diagnosis. However, if symptoms occur less frequently, clinicians must choose one of the other available monitoring devices. Most importantly, choice of device should depend on which device is most likely to detect the rhythm disturbance. Other cardiac testing such as echocardiography, stress testing, endomyocardial biopsy, genetic testing, electrophysiologic testing, or cardiac magnetic resonance imaging may be indicated as well. The majority of palpitations in athletes will be first identified by screening examination, or by a complaint from the athlete. The third and most current pre-participation examination monograph recommends asking the athlete if he/she has palpitations with exercise. The assumption has been made that palpitations occurring at rest in athletes are benign, but this theory has not been validated prospectively in a large cohort of the athletic population. Specific rhythms can often be treated with radiofrequency ablation, with return to sports provided there is no significant high risk underlying heart disease present. Athletes with known malignant ventricular rhythm disturbances, or underlying substrate for such, who have undergone implantation of an automatic implanted cardioverter-defibrillator are not recommended to return to sport because there is no data on the safety and efficacy of defibrillators in this clinical setting, and certain athletic activities may result in damage to the device.

Electrocardiograms in athletes: interpretation and diagnostic accuracy.

PURPOSE: Electrocardiography (ECG) has been proposed as a method to enhance the ability of the preparticipation examination (PPE) to detect underlying cardiac conditions that can lead to sudden cardiac death (SCD) in young athletes. METHODS AND RESULTS: We conducted a Medline review of the published medical literature, using the key terms of cardiovascular screening of athletes, ECG in athletes, SCD in athletes, and ECG in specific cardiac disease states: hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, dilated cardiomyopathy, myocarditis, long QT syndrome, Brugada syndrome, coronary artery anomalies, myocardial bridging, aortic stenosis, mitral valve prolapse, and Marfan syndrome. ECG seems to increase the sensitivity of the PPE from 2.5-6% to 50-95%. Overall sensitivity appears to be about 50%; false-positive rates can be as high as 40%, and there is at least a 4-5% false-negative rate. In Europe, ECG-based screening programs have been associated with a decline in the SCD rate in young athletes, but similar programs are currently not recommended in the United States for many reasons: lack of randomized trial data; cost of screening; lack of a clear standard for ECG interpretation in the athlete; the likelihood that asymptomatic athletes with underlying lethal conditions might differ significantly from symptomatic individuals with the same conditions; and concern that ECG screening might actually increase the death rate, via treatment-related procedural complications. CONCLUSIONS: Although some authorities advocate the use of ECG screening of young athletes, further studies are required to define what constitutes a normal ECG in athletes, and to determine whether ECG-based screening protocols truly are superior, not only in finding disease, but also saving lives. For those who either choose ECG-based screening or interpret ECG in athletes, we propose a simple interpretation scheme and decision tree.

Utility of impedance cardiography for the identification of short-term risk of clinical decompensation in stable patients with chronic heart failure.

OBJECTIVES: This study sought to assess the potential utility of impedance cardiography (ICG) in predicting clinical deterioration in ambulatory patients with heart failure (HF). BACKGROUND: Impedance cardiography uses changes in thoracic electrical impedance to estimate hemodynamic variables, but its ability to predict clinical events has not been evaluated. METHODS: We prospectively evaluated 212 stable patients with HF and a recent episode of clinical decompensation who underwent serial clinical evaluation and blinded ICG testing every 2 weeks for 26 weeks and were followed up for the occurrence of death or worsening HF requiring hospitalization or emergent care. RESULTS: During the study, 59 patients experienced 104 episodes of decompensated HF (16 deaths, 78 hospitalizations, and 10 emergency visits). Multivariate analysis identified 6 clinical and ICG variables that independently predicted an event within 14 days of assessment. These included three clinical variables (visual analog score, New York Heart Association functional class, and systolic blood pressure) and three ICG parameters (velocity index, thoracic fluid content index, and left ventricular ejection time). The three ICG parameters combined into a composite score was a powerful predictor of an event during the next 14 days (p = 0.0002). Visits with a high-risk composite score had 2.5 times greater likelihood and those with a low-risk score had a 70% lower likelihood of a near-term event compared with visits at intermediate risk. CONCLUSIONS: These results suggest that when performed at regular intervals in stable patients with HF with a recent episode of clinical decompensation, ICG can identify patients at increased near-term risk of recurrent decompensation.

Titration of carvedilol in elderly heart failure patients.

Physicians may withhold beta blockers from elderly heart failure patients based on perceptions of poor tolerability in this group. This study analyzed the success and tolerability of carvedilol titration in elderly (70 years and older) and younger (younger than 70) heart failure patients (n=360). The mean duration of titration was similar in both groups. The target carvedilol dosage (50 mg/d) was achieved by 55.3% and 62.0%, and a partial dose was achieved by 44.7% and 35.5% (p=0.028) of elderly and younger patients, respectively. The mean achieved dosage was lower in elderly patients than in younger patients (42.4+/-27.2 mg/d vs. 55.1+/-30.1 mg/d; p<0.0001), possibly due to significant between-group differences in baseline characteristics or rates of target dose achieved. When adjusted for body weight, the mean achieved dose was similar in elderly (0.58+/-0.32 mg/kg/d) and younger (0.64+/-0.30 mg/kg/d) patients (p=nonsignificant). Adverse events were more frequent in the elderly but did not appear to significantly impact titration duration or carvedilol dose achieved when corrected for body weight. In conclusion, carvedilol should not be withheld from elderly heart failure patients based on perceptions of poor potential tolerability.