64 slice cardiovascular CT in the emergency department: concepts and first experiences

The purpose of this study was to evaluate contrast-enhanced electrocardiogram (ECG)-gated 64-slice computed tomography (CT) angiography of the thorax as a triage tool in patients with acute equivocal chest pain.

Technical principles and diagnostic algorithms for using a single ECG-gated 64-slice CT scan for triple rule-out of acute pulmonary embolism, aortic dissection, acute coronary syndromes and other diseases of the chest are introduced. Our experience using this test in 23 patients are reviewed and exemplary cases are illustrated. The total length of hospitalisation and charges for Emergency Department care at the time of discharge were compared with a matched control population that underwent catheter angiography for emergent cardiac workup. Statistical analyses were performed with an independent Student's t test. Mann-Whitney rank sum test was also used on variables that did not have equal variance.

Of the 23 patients, 11 presented without pathological findings, two with extensive pulmonary embolism, two with definite coronary artery disease (CAD) but stenosis <50% and eight with significant CAD (>50% stenosis). Catheter angiography was performed in the latter group, confirming the CT findings in all cases. Nine patients without CT findings were discharged on the same day. In comparison with the control group, length of hospitalisation (p=0.009) and total hospital charges (p<0.001) were significantly reduced.

Our initial experience shows that ECG-gated 64- slice CT angiography of the entire thorax is technically feasible and enables rapid triage of patients to determine underlying cardiac and noncardiac reasons for chest pain. This test may thus help to significantly reduce costs and length of hospitalisation. Prospective studies involving larger groups of patients are required to confirm these findings.