Value of the Oxygen Pulse Curve for the Diagnosis of Coronary Artery Disease

This study investigated the value of oxygen (O-2) pulse curves obtained during cardiopulmonary exercise testing (CPET) for the diagnosis of coronary artery disease (CAD). Forty patients with known coronary anatomy (35.0 % normal, 27.0 % single-vessel and 38.0 % multivessel CAD) underwent CPET with radiotracer injection at peak exercise, followed by myocardial scintigraphy. 0 2 pulse curves were classified as: A-normal, B-probably normal (normal slope with low peak value); C-probably abnormal (flat, with low peak value); or D- definitely abnormal (descending slope). Sensitivity, specificity, positive and negative predictive values of the 0 2 pulse curve pattern (A or B vs. C or D) for the diagnosis of CAD were, respectively, 38.5 %, 81.3 %, 76.9 %, and 44.8 %. The concordance rate between the abnormal 0 2 pulse curve pattern and ischemia in myocardial scintigraphy was 38.1 %. Age and the extent of scintigraphic perfusion defect, but not the abnormal 0 2 pulse curve patterns (B or C or both combined) were independently associated with CAD. In conclusion, the 0 2 pulse curve pattern has low diagnostic performance for the diagnosis of obstructive CAD, and the abnormal curve pattern was not associated with myocardial ischemia defined by scintigraphy.