Myocardial perfusion 320-row multidetector computed tomography-guided treatment strategy for the clinical management of patients with recent acute-onset chest pain: Design of the CArdiac cT in the treatment of acute CHest pain (CATCH)-2 randomized controlled trial.

AIMS: Patients admitted with chest pain are a diagnostic challenge because the majority does not have coronary artery disease (CAD). Assessment of CAD with coronary computed tomography angiography (CCTA) is safe, cost-effective, and accurate, albeit with a modest specificity. Stress myocardial computed tomography perfusion (CTP) has been shown to increase the specificity when added to CCTA, without lowering the sensitivity. This article describes the design of a randomized controlled trial, CATCH-2, comparing a clinical diagnostic management strategy of CCTA alone against CCTA in combination with CTP. METHODS: Patients with acute-onset chest pain older than 50 years and with at least one cardiovascular risk factor for CAD are being prospectively enrolled to this study from 6 different clinical sites since October 2013. A total of 600 patients will be included. Patients are randomized 1:1 to clinical management based on CCTA or on CCTA in combination with CTP, determining the need for further testing with invasive coronary angiography including measurement of the fractional flow reserve in vessels with coronary artery lesions. Patients are scanned with a 320-row multidetector computed tomography scanner. Decisions to revascularize the patients are taken by the invasive cardiologist independently of the study allocation. The primary end point is the frequency of revascularization. Secondary end points of clinical outcome are also recorded. DISCUSSION: The CATCH-2 will determine whether CCTA in combination with CTP is diagnostically superior to CCTA alone in the management of patients with acute-onset chest pain.

Value of Myocardial Perfusion Assessment With Coronary Computed Tomography Angiography in Patients With Recent Acute-Onset Chest Pain.

OBJECTIVES: The authors sought to perform a randomized controlled trial to evaluate the clinical efficacy of combined examination with coronary computed tomography angiography (CTA) and computed tomography perfusion imaging (CTP) compared to coronary CTA alone. BACKGROUND: Stress myocardial CTP may increase diagnostic specificity when added to coronary CTA in patients suspected of having ischemic heart disease. METHODS: Patients recently hospitalized for acute-onset chest pain, who had acute coronary syndrome had been ruled out by normal electrocardiograms, normal troponin levels, and relief of symptoms, and who had a clinical indication for outpatient noninvasive testing, were screened for inclusion in the CATCH-2 (CArdiac cT in the treatment of acute CHest pain 2) trial (NCT02014311). Patients were randomized 1:1 to examination with coronary CTA or coronary CTA+CTP. The primary endpoint was the frequency of coronary revascularization among patients referred for invasive coronary angiography (ICA) based on index computed tomography evaluation. Secondary endpoints were invasive procedural complications at index-related ICA, post-index cardiac death, hospital admittance because of recurrence of chest pain, unstable angina pectoris, or acute myocardial infarction, ICA, and revascularization. RESULTS: Among 300 patients allocated to the coronary CTA+CTP group, 41 (14%) were referred for ICA compared with 89 (30%) allocated to coronary CTA (p < 0.0001). The primary endpoint occurred in 50% of coronary CTA+CTP patients versus 48% of invasively examined patients (p = 0.85). The total number of revascularizations was significantly lower in the coronary CTA+CTP group compared to the coronary CTA group (n = 20 [7%] vs. n = 42 [14%]; p = 0.0045). At median follow-up of 1.5 years, the occurrence of secondary endpoints was similar in the 2 groups. CONCLUSIONS: A post-discharge diagnostic strategy of coronary CTA+CTP safely reduces the need for invasive examination and treatment in patients suspected of having ischemic heart disease. (CArdiac cT in the treatment of acute CHest pain 2-Myocardial CT Perfusion [CATCH2]; NCT02014311).