American Heart Associaton ainsi que la Societe Europeenne de Car- diologie et l’Association Europeenne de Chirurgie Cardio-Thoracique Exercise Protocols

dynamic component of VHD, which is influenced by loading conditions and ventriculo-arterial coupling and subclinical myocardial dysfunction, could be missed at rest. Stress im-aging is useful because it addresses clinical responses during exercise testing combined with assessment of the dynamic changes in valvular and ventricular function. Moreover, in patients with low-flow, low-gradient aortic stenosis (AS), dobutamine stress echocardiography (DSE) is recommended to differentiate true severe AS from pseudosevere AS.1,2 The purpose of this article is to describe the role of exercise testing Exercise testing is the first choice over pharmacological stress for risk stratification of asymptomatic VHD patients. By decreasing preload and afterload, pharmacological stress with dobutamine has limited utility, except in patients with AS and low LV ejection fraction (LVEF).3 Safety of exercise testing has been demonstrated and complications remain low, especially in the semisupine position with a lower risk of hemodynamic collapse compared with treadmill.4,5 A comprehensive clinical evaluation to rule out the presence of symptoms and to identify potential contraindications is essential before undergoing ex-ercise testing. Contraindications to exercise testing include: clear indications for valve surgery (ie, symptomatic severe AS or mitral stenosis [MS], uncontrolled hypertension or arrhyth-mias, physical/mental disability, or systemic disease with the inability to adequately exercise).6 A symptom-limited exercis