64-slice CT coronary angiography in patients with non-ST elevation acute coronary syndrome

Background: A high diagnostic accuracy of 64-slice CT coronary angiography (CTCA) has been reported in selected patients with stable angina pectoris, but only scant information is available in patients with non-ST elevation acute coronary syndrome (ACS). Objectives: To study the diagnostic performance of 64-slice CTCA in patients with non-ST elevation ACS. Patients and methods: 64-slice CTCA was performed in 104 patients (mean (SD) age 59 (9) years) with nonST elevation ACS. Two independent, blinded observers assessed all coronary arteries for stenosis, using conventional quantitative angiography as a reference. Coronary lesions with >= 50% luminal narrowing were classified as significant. Results: Conventional coronary angiography demonstrated the absence of significant disease in 15% (16/ 104) of patients, and the presence of single-vessel disease in 40% (42/ 104) and multivessel disease in 44% (46/ 104) of patients. Sensitivity for detecting significant coronary stenoses on a patient-by-patient analysis was 100% (88/ 88; 95% CI 95 to 100), specificity 75% (12/ 16; 95% CI 47 to 92), and positive and negative predictive values were 96% (88/ 92; 95% CI 89 to 99) and 100% (12/ 12; 95% CI 70 to 100), respectively. Conclusion: 64-slice CTCA has a high sensitivity to detect significant coronary stenoses, and is reliable to exclude the presence of significant coronary artery disease in patients who present with a non-ST elevation ACS.