title: The prognostic value of CT coronary angiography in patients attending hospital with troponin-negative acute chest pain and inconclusive exercise treadmill tests.
abstract: OBJECTIVE
  Once acute coronary syndrome (ACS) is excluded in patients presenting to hospital with acute chest pain, usual practice is to stratify future risk of adverse cardiovascular events. Commonly this is performed by pre-discharge exercise treadmill testing (ETT). Often however, patients are unable to perform the test for various reasons, or the final result is inconclusive. This potentially could lead to uncertainty and to unnecessary invasive coronary angiography. We wished to evaluate the potential prognostic significance of CT coronary angiography (CTCA) in patients with prior inconclusive ETTs.
  
  
  RESULTS
  Two hundred and thirty-two consecutive patients underwent CTCA and calcium scoring following hospital attendance with acute chest pain and following exclusion of ACS. All patients were followed up for a combined primary outcome of death, non-fatal myocardial infarction, and late revascularization. The mean follow-up period was 2.5 ± 0.9 years. The combined primary outcome occurred in 26 patients (11.2%). Calcium score (HR 1.16; 95% CI 1.02-1.31, P = 0.023 per 100 Agatston unit increase), the presence of coronary artery disease (CAD) on CTCA (non-obstructive CAD, HR 4.52; 95% CI 1.30-15.73, P = 0.018; obstructive CAD, HR 17.00; 95% CI 4.60-62.85, P < 0.001), and ≥3 segments with non-calcified plaque (HR 3.30; 95% CI 1.24-8.76, P = 0.017) were significant univariable predictors of the primary outcome. CTCA was the only significant multivariable predictor of adverse outcome.
  
  
  CONCLUSIONS
  The presence of CAD assessed by CTCA is a strong predictor of adverse events in patients with troponin-negative acute chest pain and could potentially be used as an alternative, non-invasive risk stratifier in patients with inconclusive exercise tests.
authors.affiliation: BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow G12 8TA, UK ifyrmordi@doctors.org.uk ify.mordi@glasgow.ac.uk.
authors.forename: Ify
authors.initials: I
authors.lastname: Mordi
authors.affiliation: BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow G12 8TA, UK.
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Tzemos
mesh_terms: D054058:Acute Coronary Syndrome / Q000097:blood / Q000150:complications / Q000175:diagnosis*; D015415:Biomarkers / Q000097:blood; D002637:Chest Pain / Q000097:blood / Q000000981:diagnostic imaging* / Q000209:etiology; D017023:Coronary Angiography / Q000379:methods*; D005080:Exercise Test; D005260:Female; D006801:Humans; D007297:Inpatients; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D012307:Risk Factors; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014336:Troponin / Q000097:blood*
chemical_list: D015415:Biomarkers; D014336:Troponin
keywords: CT coronary angiography; acute chest pain; calcium scoring; exercise tolerance testing; prognosis