Accuracy of Multi-Slice Computed Tomography Angiography in The Diagnosis of In-Stent Restenosis in Proximal Left Anterior Descending Coronary Artery Stent Compared to Conventional Coronary Angiography

Abstract

ince the introduction of multidetector computed tomography (CT), CT angiography has emerged as a new tool in the diagnosis and monitoring of coronary heart disease. Additionally, noninvasive assessment of coronary stents is an attractive potential application of multidetector CT technology. But stent imaging is a challenge at CT, mainly because of high-attenuation stent-related artifacts. The blooming effect caused by a combination of partial volume averaging and be hardening results in higher CT attenuation values in the stent lumen and enlarges the apparent size of the stent struts, leading to an artificial appearance of narrowing of the lumen. Our study included 50 stents placed in the proximal segment of the left anterior descending coronary artery regardless their diameters and strut thickness assessed by MSCT and CA to assess the accuracy of MSCT in the diagnosis of significant in stent restenosis. Our results showed that MSCT is an accurate and reliable tool in diagnosis of in stent restenosis in stents more than 3mm in diameter with 100% sensitivity and specificity. However this accuracy drops markedly in the assessment of stents less than 3mm in diameter due to an artificial narrowing of the stent diameter caused by the blooming effect. Although MSCT can’t be reliable in diagnosis o