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The chest radiograph provides information about heart size (with cardiomegaly being a poor prognostic sign in chronic heart failure), the pulmonary circulation (with characteristic signs suggesting both pulmonary arterial or pulmonary venous hypertension), primary pulmonary disease, and aortic abnormalities. Individual chamber sizes can be estimated, and the presence of pleural effusions noted. The echocardiogram, though, provides more reliable cardiac information than the chest radiograph about chamber size and hypertrophy, and the presence of pericardial effusions, valvular abnormalities, and congenital abnormalities (VIDEO 10–1). Use of regional stress/strain measures and Doppler flow patterns can also contribute to the assessment of myocardial dysfunction and valvular abnormalities. The ECG indicates cardiac rhythm, reveals conduction abnormalities, and provides evidence of ventricular hypertrophy, MI, or ischemia (eFigures 10–10 and 10–11). ST segment and T wave changes may reflect these processes but are also noted with electrolyte imbalance, medication effects, and many other conditions (eFigure 10–12). Routine radiographs and ECGs, however, are not recommended to screen for heart disease in otherwise asymptomatic patients without any clinical findings to suggest heart disease is present. Stress testing is useful in eliciting ischemia due to fixed coronary lesions, but its use is limited for accurately diagnosing coronary disease in the typical asymptomatic patient. For instance, it is useful to recall Bayes theorem when contemplating stress testing patients as part of an “executive physical.” Bayes theorem notes that the accuracy of the results of a test depend on the risk of disease. If the patient is at low risk for CAD, for instance, one can expect a high number of false-positive stress results. If the patient is at high risk for CAD, one can expect a high number of false-negative results. Stress studies are most effective in those with an intermediate risk for CAD. The clinician’s goal is to help define the CAD risk using the history, physical examination, and other available laboratory tests. The Framingham Risk scoring system and the 10-year atherosclerotic risk calculator (http://my.americanheart.org/cvriskcalculator) can help, and these are readily available as free applications for mobile devices. Stress testing may also be useful in non-CAD patients whenever symptoms seem disproportionate to anatomic defects. For instance, in valvular disease, if the patient is complaining of major symptoms but has only minor anatomic disease, a stress study may help define exercise capacity. The stress may be combined with echocardiography to further assess ventricular function, valvular regurgitation or stenosis or pulmonary pressures. In patients with aortic stenosis, a failure of the BP to increase with stress is used as an indicator of the need for aortic valve replacement or implies high risk in patients with hypertrophic cardiomyopathy. Similarly, if there is significant disease by echocardiography, but few or no symptoms, the stress study may define an unrecognized disability. Stress ECG and pulmonary function testing (cardiopulmonary stress testing) are used together to define maximal cardiac output (VO2max) with exertion and the slope of the ratio of expiratory ventilation/carbon dioxide ...