DIAGNOSTIC ACCURACY OF 64-SLICE COMPUTED TOMOGRAPHY CORONARY ANGIOGRAPHY IN PATIENTS WITH LOW-TO-INTERMEDIATE RISK

Purpose. Our aim was to evaluate the diagnostic accuracy of 64- slice computed tomography coronary angiography (MSCT-CA) for detecting significant stenosis (≥50% lumen reduction) in a population of patients at low to intermediate risk. Materials and methods. We studied 72 patients (38 men, 34 women, mean age 53.9±8.0 years) with atypical or typical chest pain and stratified in the low- to intermediate risk category. MSCT-CA (Sensation 64 Cardiac, Siemens, Germany) was performed after IV administration of 100 ml of iodinated contrast material (Iomeprol 400 mgI/ml, Bracco, Italy). Two observers, blinded to the results of conventional coronary angiography (CAG), assessed the MSCT-CA scans in consensus. Diagnostic accuracy for detecting significant stenosis was calculated. Results. CAG demonstrated the absence of significant disease in 70.1% of patients (51/72). No patient was excluded from MSCTCA. There were 37 significant lesions on 1,098 available coronary segments. Sensitivity, specificity and positive and negative predictive value of MSCT-CA for detecting significant coronary artery on a per-segment basis were 100%, 98.6%, 71.2% and 100%, respectively. All patients with at least one significant lesion were correctly identified by MSCT-CA. MSCT-CA scored 15 false positives on a per-segment base, which affected only marginally the per-patient performance (only one false positive). Conclusions. We concluded that 64-slice CT-CA is a diagnostic modality with high sensitivity and negative predictive value in patients at low to intermediate risk.