Role of 64 MDCT Angiography in Quantification of Coronary Artery Luminal Stenosis in Patients with Ischemic Heart Disease Comparative Study with Coronary Angiography

Abstract

In the evaluation of patients with suspected coronary artery disease (CAD), the role of non-invasive imaging has increased exponentially over the past decades, particularly in patients with low likelihood of CAD. Non-invasive imaging plays an important role in risk stratification and selection of further treatment strategies. More recently, multi-slice computed tomography (MSCT) has been proposed as an alternative imaging modality for evaluation of patients with suspected CAD. With the recently introduced 64-slice MSCT, high sensitivity (93.5%) and specificity (91.3%) for the detection of significant (>50% luminal narrowing) stenoses have been reported which has made non-invasive coronary angiography using 64-slice CT a modality that allows significant coronary stenoses to be reliably excluded. Non-invasive coronary MSCT can visualize the coronary artery lumen, artery wall, and atherosclerotic plaque; even the lipid pool can be visualized. This study included 30 patients who underwent both the MDCT and ICA. The current study aimed at evaluating the role of MSCT in assessing lesion severity, diameter & length, compared to conventional coronary angiography QCA, & hence its role in defining reference value for stent diameter & length before PCI. Material to be analysed was highly selected. All vessels images with artefacts were excluded. All vessels improperly opacified were excluded. Stenoses below 50% did not participate in the results for the sake of clinically relevant outcome. The MDCT exam for evaluating the coronary stenosis included a primary step; the calcium scoring, which although seems like an independent study, still proved to be closely related to our study providing us with data about a parameter that affected our results significantly. Also discussing our results in comparison to other studies allowed us to develop an idea on how other parameters might increase or decrease the sensitivity of the MDCT in face of the gold standard ( for example using MLA instead of MLD or coupling FFR measurement with stenosis degree measurement). The comparison with other studies also showed how evoulution of multidetector technology might in itself improve the sensitivity of MDCT in quantification of luminal stenosis of the coronary arteries, especially the 156 and 320 MDCT units are expected owing to a high temporal resolution to perform a detailed segmental analysis of the coronary tree. Patients with heavy calcification, multiple motion artefacts at MSCT imaging, chronic total occlusion (CTO) or in which PCI failed were excluded from the study. All patients had the MSCT conducted using a 64-slice Toshiba CT scanner. The study included a pre scan calcium scoring, followed by a contrast enhanced scan. All patients had their invasive coronary angiographies.