Comparison of Coronary Computed Tomography Angiography and Invasive Coronary Angiography in Nonobstructive Coronary Artery Disease: The Brazilian Coronary ARtery Disease (BARD) Study.

BACKGROUND

The prognosis of nonobstructive coronary artery disease (CAD) is not well established. Comparative data between coronary computed tomography angiography (CCTA) and invasive coronary angiography (ICA) are limited.

OBJECTIVES

To compare CCTA- and ICA-derived information in nonobstructive CAD regarding detection and clinical outcomes.

METHODS

We followed 4,004 adult patients who underwent either ICA (n = 2,355) or CCTA (n = 1,649) for a median of 9 years. The primary endpoint was a composite of all-cause mortality, acute coronary syndrome/acute myocardial infarction, and stroke. Propensity score matching was performed to compare outcomes between groups. The significance level was set at 5%.

RESULTS

The overall event rate was 6.9%. ICA was associated with worse outcomes than CCTA (hazard ratio [HR] 0.54; 95% CI 0.42-0.68; p < 0.001). Patients with nonobstructive CAD had worse outcomes than those without CAD (HR 1.73; 95% CI 1.32-2.27; p < 0.001). Normal coronary findings on CCTA were associated with better outcomes than normal findings on ICA (HR 0.39; 95% CI 0.24-0.62; p < 0.001). Event rates increased proportionally with plaque burden. In 1,187 matched pairs, CCTA was associated with improved survival (HR 0.57; 95% CI 0.42-0.78; p < 0.001).

CONCLUSION

CCTA more closely reflects clinical outcomes than ICA. Nonobstructive CAD carries a substantial risk regardless of imaging modality.