CCTA has been emerged as useful diagnostic tool to evaluate CAD. Besides high diagnostic accuracy, CCTA has additional benefit of measuring the cumulative atherosclerotic burden and more accurately discriminating obstructive CAD with additional fractional flow reserve by CT (FFRCT), making it more predictive of a patient's prognosis. Recently, several randomized clinical trials have demonstrated the clinical utility of CCTA when compared with noninvasive stress test, which has been previously widely used as an initial assessment for stable chest pain, or invasive coronary angiography, which is the gold standard for diagnosing obstructive CAD.~On this background, CCTA, along with stress imaging test, is recommended as first step to diagnose obstructive CAD in patients with intermediate to high pretest probabilities with stable chest pain and is increasingly utilized. Although CCTA is increasingly used as initial assessment tool in these patients, there are insufficient studies to clearly establish the next step after obstructive CAD is confirmed in CCTA. Without high-risk features of CAD on CCTA, current guidelines suggest noninvasive stress imaging or FFRCT as class IIA recommendation. However, supporting evidence of these suggestions are mostly based on studies with low level of evidence. Furthermore, given the limited diagnostic performance of noninvasive stress test, concern remains whether it is safe to defer invasive coronary angiography based on the result from noninvasive stress test in patients with obstructive CAD on CCTA.~Therefore, this trial aims to compare clinical outcomes between invasive versus non-invasive approach as next diagnostic step in symptomatic patients with non-high risk obstructive CAD on CCTA.
A pragmatic, prospective, multi-center, open label, randomized controlled, superiority trial.~The study will compare clinical outcomes between invasive versus non-invasive approach as next diagnostic step in symptomatic patients with non-high risk obstructive coronary artery disease (CAD) on coronary computed tomography-angiography (CCTA).