Dejana Popovic1, Dejana Martic2, Tea Djordjevic2, Vesna Pesic2, Marco Guazzi3, Jonathan Myers4, Reza Mohebi5, Ross Arena6. 1. Division of Cardiology, Faculty of Medicine, University of Belgrade, Visegradska 26, 11000 Belgrade, Serbia; Department of Physiology, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11000 Belgrade, Serbia. Electronic address: dejanap@pharmacy.bg.ac.rs. 2. Department of Physiology, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11000 Belgrade, Serbia. 3. Heart Failure Unit and Cardiopulmonary Laboratory, Cardiology, I.R.C.C.S, Policlinico San Donato, University Hospital Milan, Italy. 4. VA Palo Alto Health Care System, Cardiology 111C, 3801 Miranda Ave, Palo Alto, CA 94304, USA. 5. Division of Cardiology, Department of Medicine, University of California, 2130 Fulton Street, San Francisco, CA 94117-1080, USA. 6. Department of Physical Therapy, Department of Kinesiology and Nutrition, University of Illinois Chicago, 1200 W Harrison St, Chicago, IL 60607, USA.
Abstract
BACKGROUND: Revascularization appears to be beneficial only in patients with high levels of ischemia. This study examined the utility of gas analysis during the recovery phase of cardiopulmonary exercise testing (CPET) in predicting coronary artery disease (CAD) severity and prognosis. METHODS: 40 Caucasian patients (21.2% females), mean age 63.5±7.6 with significant coronary artery lesions (≥50%) were studied. Within two months of coronary angiography, CPET on a treadmill (TM) and recumbent ergometer (RE) were performed on two visits 2-4days apart; subjects were subsequently followed 32±10months. Myocardial wall motion was recorded by echocardiography at rest and peak exercise. Ischemia was quantified by the wall motion score index (WMSI). RESULTS: Mean ejection fraction was 56.7±9.6%. Patients with 1-2 stenotic coronary arteries (SCA) showed a poorer CPET response during the recovery phase than patients with 3-SCA. ROC analysis revealed the change of carbon-dioxide output (∆VCO2) recovery/peak (area under ROC curve 0.77, p=0.02, Sn=87.5%, Sp=70.4%) and oxygen uptake (∆VO2) recovery/peak during TM CPET (area under ROC curve 0.76, p=0.03, Sn 75.0%, Sp 77.8%) were significant in distinguishing between 1-2-SCA and 3-SCA. The same variables predicted ΔWMSI peak/rest on univariate analysis (p<0.05). Multivariate Cox analysis revealed a high predictive value of ∆VO2 recovery/peak obtained during TM CPET for composite endpoint of cumulative cardiac events (HR=1.27, CI=1.07-1.51, p=0.008). CONCLUSIONS: The current study suggests CPET parameters in recovery hold predictive value for CAD severity and prognosis. TM testing seems to be a better approach in the assessment of CAD severity and prognosis.
BACKGROUND: Revascularization appears to be beneficial only in patients with high levels of ischemia. This study examined the utility of gas analysis during the recovery phase of cardiopulmonary exercise testing (CPET) in predicting coronary artery disease (CAD) severity and prognosis. METHODS: 40 Caucasian patients (21.2% females), mean age 63.5±7.6 with significant coronary artery lesions (≥50%) were studied. Within two months of coronary angiography, CPET on a treadmill (TM) and recumbent ergometer (RE) were performed on two visits 2-4days apart; subjects were subsequently followed 32±10months. Myocardial wall motion was recorded by echocardiography at rest and peak exercise. Ischemia was quantified by the wall motion score index (WMSI). RESULTS: Mean ejection fraction was 56.7±9.6%. Patients with 1-2 stenotic coronary arteries (SCA) showed a poorer CPET response during the recovery phase than patients with 3-SCA. ROC analysis revealed the change of carbon-dioxide output (∆VCO2) recovery/peak (area under ROC curve 0.77, p=0.02, Sn=87.5%, Sp=70.4%) and oxygen uptake (∆VO2) recovery/peak during TM CPET (area under ROC curve 0.76, p=0.03, Sn 75.0%, Sp 77.8%) were significant in distinguishing between 1-2-SCA and 3-SCA. The same variables predicted ΔWMSI peak/rest on univariate analysis (p<0.05). Multivariate Cox analysis revealed a high predictive value of ∆VO2 recovery/peak obtained during TM CPET for composite endpoint of cumulative cardiac events (HR=1.27, CI=1.07-1.51, p=0.008). CONCLUSIONS: The current study suggests CPET parameters in recovery hold predictive value for CAD severity and prognosis. TM testing seems to be a better approach in the assessment of CAD severity and prognosis.