Computerized helicoidal tomography of the coronary arteries vs coronary angiography

INTRODUCTION: The calcium score (CS) of the coronary arteries by computed tomography (CT) is an useful procedure for the diagnosis of obstructive coronary disease (OCD), with an average sensitivity of 82 +/- 6%, specificity of 88 +/- 2%, positive predictive value (PPV) of 57 +/- 7% and negative predictive value (NPV) of 96 +/- 2%. The objective of this trial was to compare helicoidal CT Scan with the traditional method and define sensitivity, specificity, Positive predictive value and negative predictive value against the coronary angiography. METHODS: From June of 1998 to March of 1999, one hundred and sixty six patients with coronary arteries CT were studied. The CT was done with an ELSCINT-CT Twin equipment and a software for the quantification of the coronary arteries CS in Hounsfield units. In forty one, coronary angiography was performed. A significant obstructive lesion was defined as > or = 70% of luminal stenosis in at least one artery, or > or = 50% in the left main and > or = 50% if some other artery was involved. This group was divided in accordance to the CS in two subgroups: A with a CS < or = 150 and B those with a CS > or = 151. RESULTS: In group A, 45% had significative lesions vs 95% in group B (p = 0.001). The sensitivity was 65%, specificity 95%, PPV 64% and the NPV 92%. Relative risk 2.08 (CI 95% 1.38-3.54) and Odds ratio 21.6 (CI 95% 2.43-191.37). CONCLUSIONS: Even though the small sample, CT is an useful procedure for the diagnosis of the OCD.