title: Diagnosis of coronary artery disease by multigated radionuclide angiography during right atrial pacing.
abstract: Right atrial pacing in conjunction with radionuclide angiography was used as a method to augment gradually myocardial oxygen demand in seven normal subjects and 11 patients with angiographically documented coronary artery disease (CAD). In five of the seven normal subjects the ECG during atrial pacing was normal and falsely pathologic in the two others; in all seven the ejection fraction (64 +/- 8 percent) did not change during the pacing. The atrial pacing was positive in seven of the eleven patients with CAD and falsely negative in four. In comparison, nine of these patients had more than 15 percent reduction in ejection fraction, while only two were regarded as negative. A maximal decrease of 31 percent in the average ejection fraction was observed in CAD patients at a pacing rate of 160/min. Wall motion pattern remained normal in all seven normal subjects, while new wall motion abnormalities developed during the atrial pacing in nine of the 11 CAD patients. We concluded that changes in ejection fraction induced by atrial pacing are sensitive indicators of myocardial ischemia. In patients with CAD, ejection fraction falls during pacing compared with normal subjects in whom ejection fraction remains unchanged.
mesh_terms: D000328:Adult; D002304:Cardiac Pacing, Artificial; D003327:Coronary Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D004562:Electrocardiography; D005260:Female; D006321:Heart / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging