Role of 64-slice cardiac computed tomography in the evaluation of patients with non-ST-elevation acute coronary syndrome.

PURPOSE

This study was done to evaluate the feasibility, sensitivity and specificity of 64-slice computed tomography (CT) in identifying haemodynamically significant (>50%) coronary artery stenoses in patients with suspected acute coronary syndrome (ACS) by correlating the CT findings with the clinical event and data provided by conventional coronary angiography (CCA).

MATERIALS AND METHODS

Sixty-four patients (38 men and 26 women; mean age 65 years; range+/-10 years) presenting to our hospital's emergency department with a clinical suspicion of ACS were studied with 64-slice CT followed by CCA within 24 h of arrival.

RESULTS

Two patients (3.1%) were excluded from the analysis due to artefacts. Per-patient analysis in the remaining 62 patients identified 24 cases (38.7%) of negative CT findings (no stenoses or stenoses <50%), 35 cases of positive CT findings (56.4%) with identification of the culprit lesion, two cases in which the culprit lesion was not identified and one patient with unconfirmed stenosis. Sensitivity and specificity were 94.6% and 96%, respectively. Per-vessel analysis (186 vessels) revealed 17 non-evaluable vessels (9.1%) due to motion artefacts, 61 vessels (32.8%) with stenosis >50%, seven overestimated vessels (3.7%) due to extensive calcifications, three vessels (1.6%) with underestimated stenosis and 98 vessels (52.6%) without stenosis. Sensitivity and specificity were 95.3% and 93.3%, respectively.

CONCLUSIONS

In this type of emergency, coronary CT angiography could lead to considerably lower healthcare costs by identifying patients without coronary disease and allowing immediate discharge without any need for further diagnostic procedures.