Utility of 64 detector coronary computed tomographic angiography in patients with and without prior equivocal stress tests

Abstract

This study sought to compare and the utility of cardiac computed tomographic angiography (CCTA) in patients with and without prior equivocal stress testing, and the subsequent need for invasive angiography and revascularization after CCTA. Evidence for the clinical utility of CCTA in the assessment of low to intermediate risk patients with equivocal stress testing is limited. Consecutive patients referred for outpatient CCTA for evaluation of suspected CAD with and without prior equivocal stress testing were included. CCTA studies were performed on a 64 detector scanner (Toshiba Aquilion). The diagnostic yield of CCTA for coronary stenoses and the subsequent need of the patients for invasive angiography and revascularization was evaluated. Of 228 patients evaluated, 43.9% were male, average age 59.3 ± 10.3. 66.2% (n = 151) had an equivocal stress test prior to CCTA. The prevelance of significant lesions (>50% stenosis) was high at 31% (n = 71), and was similar for those with and without a prior equivocal stress test (29.1 vs. 35.0%, P = NS). During a mean follow up of 1.4 ± 0.4 years, all patients with normal or stenosis by CCTA of <50% remained free from revascularization. Among those with a >50% stenosis by CCTA, the revascularization rate was 33.8%. The rates of angiography and revascularization were similar in those with or without prior stress tests (19 vs. 27%, P = 0.13 and 12 vs. 7.8%, P = 0.34 respectively). Regardless of whether or not patients had prior equivocal stress tests, CCTA detected a substantial number of obstructive CAD lesions and effectively identified the need for subsequent invasive angiography and revascularization. It appears to be a very promising triage test in this population.