Outcomes after coronary computed tomography angiography of patients at low to intermediate risk for acute coronary syndrome

Abstract

Background: Coronary computed tomography angiography (CTA) has recently been shown to enjoy a high negative predictive value for ruling out coronary heart disease and risk stratifying patients with acute coronary syndrome (ACS). Hence, we assessed the 1-year outcome associated with a CTA-guided strategy in patients presenting to the emergency department with low to intermediate risk for ACS graded according to the GRACE score. Methods: In this case-series study, 77 consecutive patients (mean age = 49.7 ± 10.1 and 53.2% female) who presented to the emergency department with ischemic-type chest pain and low to intermediate risk for ACS were evaluated prospectively. The patients underwent coronary CTA after the measurement of troponin I. Those with nonobstructive plaques and mild stenoses ( 70% narrowing) underwent coronary angiography. The discharged patients were contacted and their medical records were reviewed to determine the rates of major adverse cardiovascular events (MACE)—comprising death, myocardial infarction, stroke, hospital admission, and revascularization. Results: A total of 89.6% of the patients were in the low-risk ACS group. There was no significant association between MACE and the subscales and the GRACE score (P > 0.05). There was no relationship between the GRACE score and the severity of coronary stenosis (P > 0.05) and the high-severity plaques (P > 0.05). However, the severity of stenoses in the proximal part of the left anterior descending artery (LAD) (P = 0.00), the mid part of the LAD (P = 0.004), and the first part of the obtuse marginal artery (P = 0.004) was associated with MACE. Furthermore, there were no relationships between MACE and the high-risk plaques and the risk factors (P > 0.05). Conclusions: CTA ruled out significant lesions and optimal treatment was accompanied by good prognoses in our patients. CTA may, therefore, be an optimal cost-benefit modality for the determination of the diagnosis and the therapeutic modality in patients at low to intermediate risk for ACS presenting to the emergency department.