Early triage of emergency department patients with acute coronary syndrome: contribution of 64-slice computed tomography angiography

Abstract

Background: Multislice computed tomography coronary angiography (MSCT-CA) is feasible in the emergency department (ED) for ruling out obstructive coronary artery disease (CAD).

Aim: To investigate a diagnostic strategy using MSCT-CA for the early triage of patients presenting to the ED with acute chest pain suggestive of acute coronary syndrome (ACS), according to the medium-term incidence of clinical events.

Methods: We conducted a single-centre, prospective, observational cohort study in 123 patients with low-risk to intermediate-risk acute chest pain suggestive of ACS. MSCT-CA was performed using dual-source 64-slice computed tomography with retrospective electrocardiographic gating. Patients without coronary artery lesions were discharged from the ED. The incidences of death, myocardial infarction and myocardial revascularization were collected during a mid-term follow-up.

Results: According to MSCT-CA, 93 patients (75.6%) had no CAD or coronary artery stenosis less or equal to 50% and 28 patients (22.8%) had stenosis more or equal to 50%. Invasive coronary angiography was performed in 29 patients (23.6%). MSCT-CA accurately identified ten patients (8.13%) with obstructive CAD requiring myocardial revascularization; all had a low TIMI score (0-2) and eight had a low GRACE score. The mean estimated effective dose of MSCT-CA was 16.3±6.4 mSv. Median follow-up was 15 months. No patient (95% CI 0-3.0%) had major adverse cardiovascular events during follow-up.

Conclusion: MSCT-CA appears to be a useful initial triage tool in the ED. When the MSCT-CA result is negative, it allows safe early discharge because of its high negative predictive value. In a significant number of cases of low-risk ACS, MSCT-CA detects severe coronary lesions and allows further dedicated diagnostic and therapeutic intervention. Reduction of radiation exposure would help acceptance in clinical practice.