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Athletes with mild AS can participate in all competitiveSports, but should undergo serial evaluations of AS severity on at least an annual basis. Athletes with moderate AS can engage in low-intensity Competitive sports (class IA). Selected athletes may Participate in low and moderate static or low and Moderate dynamic competitive sports (classes IA, IB, And IIA) if exercise tolerance testing to at least the level Of activity achieved in competition demonstrates satisfactory Exercise capacity without symptoms, STsegment Depression or ventricular tachyarrhythmias, And with a normal blood pressure response. Those 1336 Bonow et al. JACC Vol. 45, No. 8, 2005 Task Force 3: Valvular Heart Disease April 19, 2005:1334–40 Athletes with supraventricular tachycardia or multiple or Complex ventricular tachyarrhythmias at rest or with Exercise can participate only in low-intensity competitive Sports (class IA). Patients with severe AS or symptomatic patients with Moderate AS should not engage in any competitive Sports. AORTIC REGURGITATION Aortic regurgitation has multiple etiologies, as any disease affecting the aortic valve, annulus, or proximal ascending aorta can result in AR. The common etiologies are: 1) congenital bicuspid aortic valve; 2) rheumatic heart disease; 3) infective endocarditis; and 4) aortic root diseases, including Marfan syndrome, ascending aortic aneurysm, aortic dissection, systemic hypertension, and rheumatoid spondylitis. Aortic regurgitation increases LV diastolic volume and stroke volume, which may ultimately lead to LV systolic dysfunction (10). In addition, myocardial oxygen supply/ demand imbalance may develop because of the increased wall stress, LV hypertrophy, and reduced diastolic blood pressure (reduced coronary perfusion pressure). Patients with severe AR may remain asymptomatic and athletic for many years, but angina pectoris, syncope, and ventricular arrhythmias ultimately may appear. Sudden death is rare among asymptomatic patients (less than 0.2% per year [5]) but can occur. Evaluation.The hemodynamic severity of AR can be assessed noninvasively by physical examination (the severity being reflected by the degree of LV dilation and the peripheral signs of AR), chest radiography, and echocardiography. As noted previously, the upper limit of normal LV end-diastolic size is increased in the healthy, highly trained athlete (12), and this may well affect assessment of LV enlargement in the setting of AR. Because of the importance of assessing LV function and the size of the aortic root and proximal ascending aorta in determining the etiology of AR, with resulting implications for athletic participation, evaluation by echocardiography is essential. Doppler echocardiography is very sensitive in detecting any degree of AR. Similar to MR, the greatest difficulty arises in differentiating moderate and severe AR. Qualitatively, the width of the regurgitant jet and the proportion of the LV outflow tract occupied by the jet are related to the severity of the AR, as is the slope velocity profile of the diastolic jet. The regurgitant volume can also be measured quantitatively by Doppler methods (1). The LV function should be assessed serially by twodimensional echocardiography (5). Radionuclide angiography or cardiac magnetic resonance may be helpful if echocardiograms are of suboptimal quality. Exercise testing can be useful in assessing exercise capacity, especially in those patients having nonspecific or mild symptoms, and it is recommended that testing be performed to at least the level of exertion required by the proposed competitive sport. Holter monitoring with intense exercise resembling competition is recommended to detect ventricular arrhythmias in patients who wish to participate in competitive athletics. Effects of exercise.With exercise, regurgitant volume decreases because of the decrease in peripheral vascular resistance that reduces diastolic blood pressure and the decrease in diastolic filling period that accompanies the increase in heart rate (16). Because of these changes in preload and afterload, the failure of the ejection fraction to increase with exercise is of uncertain significance, and there are insuffi- cient data with which to use this finding in formulating recommendations regarding participation in competitive athletics. There are also no data to define whether severe increases in physical activity permanently affect the function of the left ventricle. For purposes of the following recommendations, hemodynamic severity of AR is graded as follows: mild _ absent to slight peripheral signs of AR, normal LV size; moderate _ peripheral signs of AR with mild-to-moderate increases in LV size with normal systolic function; and severe _ peripheral signs of AR with severe LV enlargement and/or LV systolic dysfunction. Recommendations: Date: 2016-03-03; view: 835
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