title: Usefulness of esophageal pill electrode atrial pacing with quantitative two-dimensional echocardiography for diagnosing coronary artery disease.
abstract: Noninvasive diagnosis of coronary artery disease (CAD) is difficult in patients who are unable to exercise. In this study esophageal pill electrode atrial pacing was used as a myocardial stress not requiring exercise, and changes in ejection fraction and pressure volume ratio during pacing with 2-dimensional echocardiography were quantitatively analyzed. All patients had completed a Bruce protocol treadmill exercise test and had undergone coronary arteriography. Of 26 patients, 22 were successfully paced (85%). Comparable rate-pressure products were obtained for treadmill exercise (23,500 +/- 5,900 mm Hg/min) and pacing (24,100 +/- 4,400 mm Hg/min; difference not significant). Of the 22 patients completing the study 8 had normal coronary arteries (group I) and 14 had CAD (group II). The change in ejection fraction with pacing in group I patients was not significant (3 +/- 8%). In group II ejection fraction decreased with pacing (-8 +/- 13%; p = 0.025). The pressure/volume ratio increased in group I with pacing (3.8 +/- 1.8 mm Hg/min/m2; p = 0.05) and was unchanged in group II (0.3 +/- 1.8 mm Hg/min/m2; difference not significant). Using an ejection fraction decrease with pacing or a failure to increase pressure/volume ratio with pacing as criterion for the presence of CAD, similar predictive accuracies were obtained when compared to treadmill exercise testing. Esophageal pill electrode atrial pacing with quantitative 2-dimensional echocardiography may be a useful noninvasive, nonexercise method to detect CAD.
authors: Heart Institute, Hospital of the Good Samaritan, Los Angeles, California 90017.
authors: R V
authors: RV
authors: Matthews
authors: R J
authors: RJ
authors: Haskell
authors: L E
authors: LE
authors: Ginzton
authors: M M
authors: MM
authors: Laks
mesh_terms: D000328:Adult; D000368:Aged; D002214:Capsules; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D003327:Coronary Disease / Q000175:diagnosis*; D004452:Echocardiography; D004566:Electrodes; D004947:Esophagus; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D013318:Stroke Volume
chemical_list: D002214:Capsules