Abstract 1900: Coronary MDCT based Detection of Coronary Stenosis and Plaque in the Assessment of Patients with Acute Chest Pain: Update from ROMICAT I

Abstract

Objective : To determine CT angiographic patterns of coronary plaque and stenosis and diagnostic test characteristics of these findings to predict ACS in patients presenting with acute chest pain to the emergency department (ED). Methods : We conducted a blinded, prospective, observational cohort study in patients presenting with acute chest pain to the ED between May 2005 and July 2006, who were admitted to the hospital to rule out acute coronary syndrome (ACS) with no ischemic ECG changes and negative initial biomarkers. Contrast-enhanced 64-slice cardiac CT was performed immediately before admission and caregivers were blinded to the cardiac CT results. An expert panel determined the presence or absence of ACS (unstable angina pectoris [UAP], Non-ST-Elevation Myocardial Infarction [MI] according to AHA/ACC criteria). Two independent observers evaluated cardiac CT data sets for the presence of (1) coronary atherosclerotic plaque, and (2) significant coronary artery stenosis (>50%). Results: Of 221 consecutive patients (44% female, mean age 55±12 years), 31 patients had ACS (10 NSTEMI, 21 UAP). The presence of any coronary atherosclerotic plaque could be excluded in 82 patients (37%). None of these subjects was determined to have ACS (Sensitivity and NPV: 100%, (95% CI: 0.91–1.00 and 0.96–1.00; respectively). The presence of a significant coronary artery stenosis could be excluded in 152 subjects (69%). Overall, three of these patients had ACS during the index hospitalization (NPV, 98 %; 95% CI: 0.94–1.00). In 69 patients (31%), a significant stenosis was either detected or could not be completely excluded. Among them were 28/31 patients with ACS (specificity: 78%, 95% CI: 0.72– 0.84; PPV: 41% 95% CI: 0.29 – 0.53). Conclusions : These data extend initial observations that nearly 40% and 70% of patients with acute chest pain demonstrate no detectable CAD or no significant coronary artery stenosis on cardiac MDCT, respectively. Randomized diagnostic trials are warranted to determine how this information will be used by ED physicians and whether it will decrease the number of unnecessary admissions.