Value of cardiopulmonary exercise testing in the diagnosis of coronary artery disease

Abstract

Introduction: Respiratory and cardiac functions in association with skeletal and neurophysiologic systems can be evaluated with cardiopulmonary exercise testing (CPET). Compared to treadmill exercise test, CPET provides more comprehensive data about the hemodynamic response to exercise.

Materials and Methods: We aimed to evaluate the relationship with CPET findings and coronary lesions identified on angiography in patients with angina pectoris who underwent teradmill exercise, CPET and coronary angiography (CAG). By this way we sought to examine the CPET parameters that might be predictive for coronary artery disease (CAD) before diagnostic exercise test results and ischemia symptoms develop. Thirty patients in whom CAG was planned because of symptoms and exercise test results were enrolled in the study. Oxygen consumption (VO2), carbon dioxide production (VCO2), minute ventilation (VE), maximum work rate (WR), Delta VO2/Delta WR and O-2 pulse (VO2/HR) values were calculated. Significant CAD was defined as >= 50% narrowing in at least one of the coronary arteries.

Results: The mean age was 60.4 +/- 8.9 years ve 21 (65.6%) of subjects were male. On CAG, CAD was detected in 19 (59.4%) patients. Maximum heart rate, heart rate reserve (HRR), VE/VCO2 measured at anaerobic threshold AT) and VO2 (mL/kg/min) were significantly differed in patients with CAD than those without (p= 0.031; p= 0.041; p= 0.028; p= 0.03 respectively). Peak VO2, VO2/WR and O-2 pulse values were higher in patients with normal angiographic results than those with CAD but the difference did not reach to statistical significance.

Conclusion: The findings of our study indicate that among CPET parameters AT VE/VCO2, ATVO(2) (mL/kg/dk) and HRR can have predictive value in the diagnosis of CAD. We think that these parameters might be used in the evaluation of patients with angina and dyspnea suspected of CAD. In conclusion parameters obtained during the test that are not influenced by patient's effort might increase the value of CPET in the diagnosis CAD.