Specificity Of Coronary CT Angiography Research Articles

Coronary Computed Tomographic Angiography Findings in Diabetic Patients: A tertiary clinic findings

In coronary artery disease, it is important to define the plaque characteristics and the risk factor modifications in diabetic and nou-diabetic patients. In diabetic patients, diffuse atherosclerosis is more frequently seen and acute coronary syndromes are usuaIIy the result of a rupture from an atherosclerotic plaque which is not critically stenotic. For this reason, recognizing early coronary artery atherosclerosis is important for prevention of progression, and complications. In our study, we evaluated diabetic patients with bypass history, coronary stents, and suspected of atherosclerosis by using MDCT. We scanned a total 252 patients with CT angiography. 75 patients with bypass and 26 patients with stents. We found that 40 patients (15%) had 1, 32 patients (12.7%) had 2, 34 patients (13.5%) had 3, 12 patients (4.8%) had 4, 1 patient (4%) had 5 arteries with at least 30% stenosis. In 133 patients, the stenosis was less than 30%. In 151 patients suspected of atherosclerosis without bypass or stent history, mostly soft atherosclerotic plaques were found (115 calcified plaques (74,2%), 124 soft plaques (80%). 68 mixed plaque (43,9%). Of 75 patients with bypass history, 57 (76%) patients had patent bypass grafts without stenosis and 18 (24%) patients had at least one stenotic bypass graft. In 12 of 26 patients with stents, invasive angiography was performed and sensitivity and specificity of coronary CT angiography were 80% and 100% in showing the stenosis. In 252 diabetic patients, the relationship between the LDL levels and plaque types (calcified, mixed, soft) and the severity of the stenosis in the proximal. middle or distal areas of the coronary arteries were not statistically significant. In conclusion, high quality coronary CT angiography permits evaluation of bypass grafts, stent restenosis, and coronary arteries nou-invasively in diabetic patients

CT Myocardial Perfusion and CT-FFR versus Invasive FFR for Hemodynamic Relevance of Coronary Artery Disease.

Background CT-derived fractional flow reserve (CT-FFR) and dynamic CT myocardial perfusion imaging enhance the specificity of coronary CT angiography (CCTA) for ruling out coronary artery disease (CAD). However, evidence on comparative diagnostic value remains scarce. Purpose To compare the diagnostic accuracy of CCTA plus CT-FFR, CCTA plus CT perfusion, and sequential CCTA plus CT-FFR and CT perfusion for detecting hemodynamically relevant CAD with that of invasive angiography. Materials and Methods This secondary analysis of a prospective study included patients with chest pain referred for invasive coronary angiography at nine centers from July 2016 to September 2019. CCTA and CT perfusion were performed with third-generation dual-source CT scanners. CT-FFR was assessed on-site. Independent core laboratories analyzed CCTA alone, CCTA plus CT perfusion, CCTA plus CT-FFR, and a sequential approach involving CCTA plus CT-FFR and CT perfusion for the presence of hemodynamically relevant stenosis. Invasive coronary angiography with invasive fractional flow reserve was the reference standard. Diagnostic accuracy metrics and the area under the receiver operating characteristic curve (AUC) were compared with the Sign test and DeLong test. Results Of the 105 participants (mean age, 64 years ± 8 [SD]; 68 male), 49 (47%) had hemodynamically relevant stenoses at invasive coronary angiography. CCTA plus CT-FFR and CCTA plus CT perfusion showed no evidence of a difference for participant-based sensitivities (90% vs 90%, P > .99), specificities (77% vs 79%, P > .99) and vessel-based AUCs (0.84 [95% CI: 0.77, 0.91] vs 0.83 [95% CI: 0.75, 0.91], P = .90). Both had higher participant-based specificity than CCTA alone (54%, both P < .001) without evidence of a difference in sensitivity between CCTA (94%) and CCTA plus CT perfusion (P = .50) or CCTA plus CT-FFR (P = .63). The sequential approach combining CCTA plus CT-FFR with CT perfusion achieved higher participant-based specificity than CCTA plus CT-FFR (88% vs 77%, P = .03) without evidence of a difference in participant-based sensitivity (88% vs 90%, P > .99) and vessel-based AUC (0.85 [95% CI: 0.77, 0.93], P = .78). Compared with CCTA plus CT perfusion, the sequential approach showed no evidence of a difference in participant-based sensitivity (P > .99), specificity (P = .06), or vessel-based AUC (P = .54). Conclusion There was no evidence of a difference in diagnostic accuracy between CCTA plus CT-FFR and CCTA plus CT perfusion for detecting hemodynamically relevant CAD. A sequential approach combining CCTA plus CT-FFR with CT perfusion led to improved participant-based specificity with no evidence of a difference in sensitivity compared with CCTA plus CT-FFR. ClinicalTrials.gov registration no.: NCT02810795 © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Sinitsyn in this issue.

COMPARISON OF COMPUTED TOMOGRAPHY WITH INTRAVASCULAR ULTRASOUND IN EVALUATION OF CORONARY PLAQUES PARAMETERS

Purpose.To determine the possibilities of coronary CT-angiography (CTA) in evaluation of qualitative and qualitative parameters of coronary plaques in comparison with intravascular ultrasound (IVUS).Matherials and methods.37 patients (29 men, 8 women) with symptoms of acute coronary syndrome (ACS) were included in the study. Unstable angina was detected in 24 patients, acute myocardial infarction (AMI) – in 13 patients. Averageage was 58 [44; 65] years. CTA had been performed as the first method of beam diagnostics in all cases if it was not necessary to use the emergency selective coronary angiography (CAG). IVUS was performed in one, two or three coronary arteries of every patient. Total, 60 coronary lesionsin 55 arteries were examined with IVUS. IVUS data was compared with CTA data.Results.Methods well correlated in detection of plaque burden (r = 0.823; p &lt; 0.0001), plaque length (r = 0.932, p &lt; 0.0001), remodeling index(RI) (r = 0.906; p &lt; 0.0001). Sensitivity and specificity of CTA in detection of irregular contour was 96.1% and 88.9% (area under ROC-curve 0.925), positive remodeling – 100% and 97.4% (area under ROC-curve 0.974). CTA and IVUS in evaluation of spotty calcinates was not coincide in 9 plaques, sensitivity and specificity of CTA in detection of 71% and 100% (area under ROC-curve 0.855).Discussion.Comparison of CTA and IVUS was performed in evaluation of plaques features in patients with ACS. This analysis showed high comparability of methods for evaluation of coronary stenosis degree, RI, plaque burden, length and contour. Thus, the characteristics of plaques according to CTA data can be used to stratify the risk of development of ACS.Conclusion.CTA – fast non-invasive method of coronary plaques evaluation. CTA correlates well with IVUS.

A survey of the current status of coronary CT angiography using 64-slice multidetector CT in Taiwan

The 64-slice multidetector CT (64-MDCT) has bolstered the sensitivity and specificity of coronary CT angiography (CCTA) for detecting coronary artery disease. We performed this study to understand the current status of CCTA using 64-MDCT, so as to determine further promotion and optimal regulation schemes of CCTA in Taiwan. Information about CCTA from 68 domestic hospitals with 64-MDCT was collected by means of a questionnaire from July 2009 to January 2010. The studied details included: (1)the implementation background of CCTA; (2) the interdisciplinary cooperation and report processing of CCTA; and (3) the promotion strategy of CCTA. The majority of CCTA sites (89.7%) were administered by diagnostic radiologists. Most cardiologists and cardiac surgeons have confirmed its clinical value by referring patients to undergo CCTA. Of the CCTA reports by radiologists, 41.2% had their report supplemented by referring cardiologists. Such cooperation amongst specialists promoted the development of CCTA. Of CCTA studies, 89.7% included coronary calcium scoring. Most (60.3%) respondents asserted the cost of a study to be 15,000 to 20,000 new Taiwan dollars. Nearly two-fifths (41.2%) of the respondents supported the restriction of subjects for CCTA to those who were high risk group for coronary artery disease or those > 40 years of age. Diagnostic radiologists are primarily in charge of managing CCTA sites in Taiwan. The interdisciplinary cooperation amongst radiologists and cardiologists in reporting CCTA may expedite the development of CCTA. The domestic radiologists are expected to standardize the process, which includes interpreting and reporting CCTA findings.

Diagnostic performance of coronary CT angiography for stenosis detection according to calcium score: systematic review and meta-analysis

A systematic review and meta-analysis to assess sensitivity and specificity of coronary CT angiography (CCTA) for significant stenosis at different degrees of coronary calcification. A literature search was performed including studies describing test characteristics of CCTA for significant stenosis, performed with at least 16-MDCT and according to calcium score (CS). Invasive coronary angiography was the reference standard. Pooled sensitivity and specificity of CCTA by CS categories and CT equipment were calculated. Of 14,121 articles, 51 studies reported on the impact of calcium scoring on diagnostic performance of CCTA and could be included in the systematic review. Twenty-seven of these studies (5,203 participants) were suitable for meta-analysis. On a patient-basis, sensitivity of CCTA for significant stenosis was 95.8, 95.6, 97.6 and 99.0% for CS 0-100, 101-400, 401-1,000 and >1,000 respectively. Specificity was 91.2, 88.2, 50.6 and 84.0% respectively. Specificity of CCTA was significantly lower for CS 401-1,000 due to lack of patients without significant stenosis. Sensitivity and specificity of 16-MDCT were significantly lower compared to more modern CT systems. Even in cases of severe coronary calcification, sensitivity and specificity of CCTA for significant stenosis are high. With 64-MDCT and newer CT systems, a CS cut-off for performing CCTA no longer seems indicated. Decisions about performing coronary CT angiography (CCTA) sometimes depend on calcium scoring. CCTA is highly sensitive for coronary stenosis. With 16-MDCT, however, heavy calcification reduces specificity for significant stenosis. For 64-MDCT (and above), CCTA has high specificity, even with severe coronary calcification.