Non-obstructive coronary artery disease assessed by coronary computed tomography angiography: Prognostic implications

L. Nielsen, H. E. Bøtker, H. Sorensen, M. Schmidt, L. Pedersen, N. P. Sand, J. Jensen, K. Ovrehus, F. Hald, B. Norgaard

Research output: Contribution to journalConference abstract in journalResearchpeer-review


Introduction: Coronary CT angiography (CTA) detects non-obstructive coronary artery disease (CAD) that may not be recognized by functional testing, but the prognostic impact is not well understood. This study aimed to compare the risk of myocardial infarction (MI) and all-cause mortality in patients without or with non-obstructive and obstructive CAD assessed by coronary CTA. Methods: Consecutive patients without known coronary artery disease (CAD) and with chest pain who underwent coronary CTA (>64-detector row) between January 2007 and December 2012 in the 10 centers participating in the Western Denmark Cardiac Computed Tomography Registry were included. The endpoints were 3-year MI or all-cause mortality. The coronary CTA result was defined as normal (0% luminal stenosis), non-obstructive CAD (1%-49% luminal stenosis) or obstructive CAD (>50% luminal stenosis; 1-vessel, 2-vessel, or 3-vessel/left main [LM]). The severity of non-obstructive CAD was assessed by the Agatston score (Ag) and categorized as zero, low (Ag, 1-99), moderate (Ag, 100-399), or high (Ag, >400). Cox regression was used to compute hazard ratios (HRs) with 95% confidence intervals (CIs) as measures of the relative risk for the occurrence of endpoints, adjusting for age, sex, conventional cardiac risk factors, comorbidity as assessed by the Charlson Comorbidity Index, and concurrent cardiovascular medical treatment. Results: Among 16,891 patients, 9,368 patients (55.4%) did not have CAD, 4,774 patients (28.3%) had non-obstructive CAD, and 2,749 patients (16.3%) had obstructive CAD. A total of 125 patients developed a MI and 148 patients died, respectively. In patients with non-obstructive CAD, no events occurred in patients with Ag=0, whereas those with moderate (HR: 1.70, 95% CI: 1.34-2.14) or high (HR: 4.35, 95% CI: 3.35-5.65) Ag levels had an increased risk of subsequent MI when compared to patients without CAD. In addition, the risk of MI was increased among patients with 1-, 2-, and 3- vessel/LM obstructive disease with HRs of 4.31 (95% CI: 3.70-5.02), 4.55 (95% CI: 3.72-5.56), and 6.07 (95% CI: 4.76-7.74), respectively. We found no significant differences in mortality risk for patients with non-obstructive CAD with Ag=0, a low or moderate Ag, and 1- or 2- vessel CAD when compared to patients without CAD, whereas mortality was associated with the presence of non-obstructive CAD with high Ag (HR: 2.96, 95% CI: 2.47-3.55) and 3-vessel/LM CAD (HR: 2.83, 95% CI: 2.32-3.45), respectively. Conclusion: In patients with non-obstructive CAD, Ag >400 was associated with an increased three-year risk of MI, similar to the risk in patients with 1- or 2-vessel obstructive CAD. Moreover, in patients with non-obstructive CAD and high Ag, mortality was comparable to the risk in patients with 3- vessel/LM obstructive CAD.
Original languageEnglish
Article number219
JournalJournal of Cardiovascular Computed Tomography
Issue number4 (Supplment)
Pages (from-to)S88
Number of pages1
Publication statusPublished - 2015
Event10th Annual Scientific Meeting of the Society of Cardiovascular Computed Tomography - Las Vegas, Nevada, United States
Duration: 16. Jul 201519. Jul 2015


Conference10th Annual Scientific Meeting of the Society of Cardiovascular Computed Tomography
Country/TerritoryUnited States
CityLas Vegas, Nevada

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