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New Approaches To Resolving Diagnostic Problems in Patients With Angina Pectoris

Several new noninvasive techniques are now available to evaluate the patient with chest pain to determine if myocardial ischemia is present. Continuous ambulatory ECG monitoring can detect myocardial ischemia in some patients who have normal ECG responses to graded exercise tests. Defects in myocardial perfusion can be visualized by radionuclide imaging at rest and after exercise. Also, abnormal left ventricular wall motion due to myocardial ischemia can be detected by gated blood pool scanning at the same time. Other techniques can olso be valuable in evaluating wall motion. Standard M-mode echocardiography can detect anteroseptal and posteroinferior wall motion abnormalities with remarkable anatomic detail, and newer echo techniques are promising for delineating the motion of other parts of the left ventricle. Finally, abnormal contractile areas can be assessed by videotracking the fluoroscopic cardiac silhouette and by a new noninvasive technique, the displacement cardiograph, which does not involve radiation exposure. Although none of these tests are both highly sensitive and highly specific for myocardial ischemia, their combined application in a symptomatic patient may provide considerable useful information which will help to determine who should be subjected to the risk and expense of coronary arteriography.