Quantification of coronary artery disease using different modalities of cardiopulmonary exercise testing

BACKGROUND: This study examined the accuracy of cardiopulmonary exercise testing (CPET) on a treadmill (TM) and recumbent ergometry (RE) in the predicting coronary artery disease (CAD) severity and prognosis.

METHODS: Forty Caucasian subjects, mean age 63.5 ± 7.6, with significant coronary artery lesions (≥50%) were included. Within two months of coronary angiography, TM and RE CPET were performed on two visits 2-4 days apart and subsequently followed up to 32 ± 10 months.

RESULTS: Mean left ventricular ejection fraction was 56.7 ± 9.6%. TM CPET exhibited a higher occurrence of ST segment depression ≥ 1 mm (71.05% vs 28.95%, p = 0.04). Subjects with 1-2 stenotic coronary arteries (SCA) demonstrated a better CPET response compared to those with 3-SCA. ROC analysis revealed a high predictive value for the ventilation/carbon dioxide production (VE/VCO2) slope obtained on TM (area 0.84, p = 0.003, Sn 88.9%, Sp 72%) in distinguishing between 1 and 2-SCA and 3-SCA. Among all CPET parameters, work efficiency (∆VO2/∆WR) during RE predicted cumulative cardiac events (p < 0.01).

CONCLUSIONS: CPET parameters hold predictive value for CAD severity and prognosis. CPET on a TM appears to be more reliable in the quantification of CAD compared to RE.