Prognostic implications of nonobstructive coronary artery disease in patients undergoing coronary computed tomographic angiography for acute chest pain

Coronary computed tomographic angiography can detect nonobstructive atherosclerotic lesions that would not otherwise have been detected with functional cardiac imaging. Currently, limited data exist regarding the clinical significance of these lesions in patients with acute chest pain. The aim of our study was to examine the prognostic significance of these nonobstructive findings in a patient population presenting with acute chest pain. We evaluated 959 consecutive patients who underwent coronary computed tomographic angiography for investigation of acute chest pain. The patients were classified as having normal (n = 545), nonobstructive coronary artery disease (CAD; defined as any narrowing <50% diameter stenosis; n = 312), or obstructive CAD (narrowing of ≥50% diameter stenosis; n = 65). Follow-up data for a minimum of 12 months (mean 27 ± 11) was obtained for any major adverse coronary events consisting of death, nonfatal acute coronary syndrome, and coronary revascularization. Compared to patients with normal coronary arteries, those with nonobstructive CAD were older and had a greater prevalence of CAD risk factors. The incidence of major adverse coronary events was equally low among both these groups (0.6% vs 1.3%, for the normal and nonobstructive groups, respectively, p = 0.2). In conclusion, patients with either nonobstructive CAD or normal findings, as evaluated by coronary computed tomographic angiography, for acute chest pain during an intermediate-term follow-up period had equally benign clinical outcomes.