Evaluation of 64-slice MDCT in the real world of cardiology: a comparison with conventional coronary angiography.

UNLABELLED: Multi-detector row computed tomography (MDCT) offers an alternative to diagnostic coronary angiography for visualizing coronary arteries. The major limitation of recently published studies, aside from being monocentric in nature and the low number of patients included, is the selection of patients. These studies do not provide any answers for patients who are seen daily in cardiology consultation. The purpose of our study was to determine the diagnostic accuracy of MDCT as compared with coronary angiography on a population of average patients who were not selected.

MATERIALS AND METHODS: Forty-eight patients with suspected coronary artery disease successively underwent 64-slice MDCT followed by coronary angiography with 24 to 48hours. The diagnostic accuracy detection of significant coronary stenoses (greater than 50% stenoses in arteries greater than 1.5mm in diameter) was determined and the two techniques were compared.

RESULTS: Nearly half of the patients included had known histories of coronary artery disease (N=24; 50%). The sensitivity, specificity, positive and negative predictive value, and the diagnostic accuracy of MDCT in detecting significant coronary stenoses were 81.2, 98.2, 87.5, 97 and 93.9% in per-segment evaluation. During the per-patient evaluation, the efficacy of MDCT dropped with the values being 77.4, 92.3, 87.8, 79.2 and 81.6% respectively.

CONCLUSION: The use of 64-slice MDCT results in excellent diagnostic accuracy and in an increased negative predictive value for detecting significant coronary stenoses in per-segment analysis. Per-patient analysis significantly reduced the value of the scan, demonstrating that patients with a high probability of coronary artery disease do not benefit from this type of non-invasive approach.