Clinical Question

For stable chest pain, what are the risks of using computed tomography angiography (CTA) as an initial diagnostic strategy for identifying obstructive coronary artery disease (CAD)?

Bottom Line

For patients with stable chest pain and an intermediate risk of obstructive CAD, an initial diagnostic strategy using CTA has a similar risk of long-term major adverse cardiovascular events compared with a strategy using invasive coronary angiography. Starting with CTA leads to a decreased need for invasive procedures and fewer procedure-related complications. (Level of Evidence = 1b)

Synopsis

In this study from Europe, the investigators enrolled patients 30 years and older who were referred for invasive coronary angiography for stable chest pain and had an intermediate pretest probability (10% to 60%) of obstructive CAD. Using concealed allocation, study patients were randomized to undergo CTA (n = 1,833) or invasive coronary angiography (n = 1,834) as an initial diagnostic strategy to identify obstructive CAD. Patients found to have obstructive CAD with this initial testing were treated according to guidelines; the others were referred to their physicians for further management. The two study groups were similar at baseline: median age was 61 years, 56% were female, and one-third had functional stress testing performed before enrollment in the trial. Overall, 25% of patients in each group were identified as having obstructive CAD. The primary outcome was a composite of major adverse cardiovascular events, including cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke. After a median follow-up of 3.5 years, the primary outcome was similar in the two groups (2.1% in the CTA group vs. 3.0% in the invasive coronary angiography group). Only 22% of patients in the CTA group had invasive coronary angiography performed during the initial management period, compared with 97% in the invasive coronary angiography group, resulting in fewer major procedure–related complications with CTA as an initial strategy (0.5% in the CTA group vs. 1.9% in the invasive coronary angiography group; hazard ratio = 0.26; 95% CI, 0.13 to 0.55). During the follow-up period, the CTA group had more functional testing (18.6% vs. 12.9%) but required fewer revascularization procedures (14.2% vs. 18.0%). There was no significant difference in the incidence of angina (less than 10% in both groups) during the last four weeks of follow-up.