Exercise-induced myocardial ischaemia detected by cardiopulmonary exercise testing

Background The objective of the study was to identify the parameter(s) of cardiopulmonary exercise testing (CPET) that can detect exercise-induced myocardial ischaemia (EIMI), and to determine its diagnostic accuracy for identifying patients with coronary artery disease (CAD). Methods and resuIts We prospectively studied 202 consecutive patients (173 men, 29 women, mean age 55.7 +/- 10.8 years) with documented CAD. All patients underwent an incremental exercise stress testing (ECG-St) with breath - by- breath gas exchange analysis, followed by a 2-day stress/rest gated SPECT myocardial scintigraphy (GSMS) as the gold standard for ischaemia detection. ROC analysis selected a two-variabte model-O-2 pulse flattening duration, calculated from the onset of myocardial ischaemia to peak exercise, and DeltaVO(2)/Deltawork rate slope-to predict EIMI by CPET. GSMS identified 140 patients with reversible myocardial defects, with a Summed Difference Score (SDS) of 9.7 +/- 2.8, and excluded EIMI in 62 (SDS 1.3 +/- 1.6). ECG-St had tow sensitivity (46%) and specificity (66%) to diagnose EIMI as compared with CPET (87% and 74%, respectively). Conclusions The addition of gas exchange analysis improves the diagnostic accuracy of standard ECG stress testing in identifying EIMI. A two-variable model based on 02 pulse flattening duration and DeltaVO(2)/Deltawork rate slope had the highest predictive ability to identify EIMI. (C) 2003 Published by Elsevier Ltd on behalf of The European Society of Cardiology.