Diagnostic performance of exercise bicycle testing and single-photon emission computed tomography: comparison with 64-slice computed tomography coronary angiography

To conduct a comparison of the diagnostic performance of exercise bicycle testing and single-photon emission computed tomography (SPECT) with computed tomography coronary angiography (CTCA) for the detection of obstructive coronary artery disease (CAD) in patients with stable angina. 376 symptomatic patients (254 men, 122 women, mean age 60.4 ± 10.0 years) referred for noninvasive stress testing (exercise bicycle test and/or SPECT) and invasive coronary angiography were included. All patients underwent additional 64-slice CTCA. The diagnostic performance of exercise bicycle testing (ST segment depression), SPECT (reversible perfusion defect) and CTCA (≥50% lumen diameter reduction) was presented as sensitivity, specificity, positive and negative predictive value (PPV and NPV) to detect or rule out obstructive CAD with quantitative coronary angiography as reference standard. Comparisons of exercise bicycle testing versus CTCA (n = 334), and SPECT versus CTCA (n = 61) were performed. The diagnostic performance of exercise bicycle testing was significantly (P value < 0.001) lower compared to CTCA: sensitivity of 76% (95% CI, 71–82) vs. 100% (95% CI, 97–100); specificity of 47% (95% CI, 36–58) vs. 74% (95% CI, 63–82). We observed a PPV of 70% (95% CI, 65–75) vs. 91% (95% CI, 87-94); and NPV of 30% (95%, 25–35) vs. 99% (95%, 90–100). There was a statistically significant difference in sensitivity (P value < 0.05) between SPECT and CTCA: 89% (95% CI, 75–96) vs. 98% (95% CI, 87–100); but not in specificity (P value > 0.05): 77% (95% CI, 50–92) vs. 82% (95% CI, 56–95). We observed a PPV of 91% (95% CI, 77–97) vs. 93% (95% CI, 81–98); and NPV of 72% (95%, 46–89) vs. 93% (95%, 66–100). SPECT and CTCA yielded higher diagnostic performance compared to traditional exercise bicycle testing for the detection and rule out of obstructive CAD in patients with stable angina.