Harshna Vinodbhai Vadvala MD, Presenter: Nothing to Disclose

Phillip Kim, Abstract Co-Author: Nothing to Disclose

Udo Hoffmann MD, Abstract Co-Author: Nothing to Disclose

Brian Burns Ghoshhajra MD, Abstract Co-Author: Nothing to Disclose

Coronary CT angiography (CCTA) is a well-established but relatively recent method for evaluation of acute chest pain in emergency department (ED) patients at low to intermediate risk for acute coronary syndrome (ACS). Traditional tests includes exercise tolerance test (ETT), nuclear imaging (SPECT-MPI), stress echocardiography and invasive coronary angiography (ICA). Each test carries its own risks, benefits and diagnostic profile. We evaluated results of CCTA as well as a second testing modality at our tertiary center’s chest pain program to discern patterns of aggrement

Patient records for all acute chest pain patients undergoing CCTA during a 17 month period (of our clinical registry) were queried. Results were considered positive at a threshold of moderate stenoses (≥50% luminal narrowing) at CCTA, ICA, or any result deemed potentially ischemic (i.e. artifacts were excluded) by ETT and SPECT. Results were stratified by CCTA results, per worst stenosis. CCTA exams followed up by ICA were also compared for accuracy, including the use of fractional flow reserve (FFR), when available.

263 patients underwent CCTA during the study period, with 52 patients undergoing a second imaging procedure or ETT (20%). The most common downstream testing was with SPECT (n=32,66%), followed by ICA (n=20,38%), ETT (n=5,10%), and both SPECT and ICA (n=4,8%). For moderate or greater stenoses, disagreement rate for CCTA vs.SPECT was 78%(n=14), CCTA vs.ETT was 100 %(n=1) and CCTA vs. ICA was 10% (n=2). Amongst the discordant cases of CCTA vs.SPECT n=2 (14%) patients, both with positive CCTA and negative SPECT underwent subsequent ICA showing severe stenosis (i.e. ICA agreement with CCTA). For CCTA vs. ICA patients, 75%(n=3) cases with moderate CCTA stenoses were discrepant with ICA result (2 were deemed mild and 1 as severe). FFR was performed in 3 cases with results of 0.88, 0.81 and 0.67 with latter two undergoing stenting. However no CCTA vs. ICA discrepancy was noted for severe stenosis and occlusion cases. There were no missed ACS events.

CCTA in ED patients results in downstream testing in a minority of cases. We observed highest agreement with anatomic testing (ICA), and lower agreement with physiologic testing (SPECT and ETT).

Practitioners and imagers may find this information useful when interpreting test results in the context of an ED population being evaluated for ACS.

Vadvala, H, Kim, P, Hoffmann, U, Ghoshhajra, B, Concordance vs. Discordance in ED Chest Pain Imaging: An Evaluation of CCTA versus Additional Downstream Testing.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14018787.html