This study compared the role of multislice computed tomography coronary angiography (MSCT-CA) and stress electrocardiography (ECG) in the diagnostic workup of patients with chronic chest pain. MSCT-CA was performed in 43 patients (31 men, 12 women, mean age 58.8+/-7.7 years) with stable angina after a routine diagnostic workup involving stress ECG and conventional CA. The following inclusion criteria were adopted: sinus rhythm and ability to hold breath for 12 s. Beta-blockers were administered in patients with heart rate>or=70 beats/minute. In order to identify or exclude patients with significant stenoses (>or=50% lumen), we determined posttest likelihood ratios of stress test and MSCT-CA separately and of MSCT-CA performed after the stress test. The pretest probability of significant coronary artery disease (CAD) was 74%. Positive and negative likelihood ratios were 2.3 [95% confidence interval (CI) 1.0-5.3] and 0.3 (95% CI: 0.2-0.7) for the stress test and 10.0 (95% CI: 1.8-78.4) and 0.0 (95% CI: 0.0-infinity) for MSCT-CA, respectively. MSCT-CA increased the posttest probability of significant CAD after a negative stress test from 50% to 86% and after a positive stress test from 88% to 100%. MSCT-CA correctly detected all patients without CAD. Noninvasive MSCT-CA is a potentially useful tool in the diagnostic workup of patients with stable angina owing to its capability to detect or exclude significant CAD.