The evolution and investigation of native coronary arteries in patients after coronary stent implantation: a study by 320-detector CT angiography

Added Value of Computed Tomography Virtual Intravascular Endoscopy in the Evaluation of Coronary Arteries with Stents or Plaques

Coronary computed tomography angiography (CCTA) is a widely used imaging modality for diagnosing coronary artery disease (CAD) but is limited by a high false positive rate when evaluating coronary arteries with stents and heavy calcifications. Virtual intravascular endoscopy (VIE) images generated from CCTA can be used to qualitatively assess the vascular lumen and might be helpful for overcoming this challenge. In this study, one hundred subjects with coronary stents underwent both CCTA and invasive coronary angiography (ICA). A total of 902 vessel segments were analyzed using CCTA and VIE. The vessel segments were first analyzed on CCTA alone. Then, using VIE, the segments were classified qualitatively as either negative or positive for in-stent restenosis (ISR) or CAD. These results were compared, using ICA as the reference, to determine the added diagnostic value of VIE. Of the 902 analyzed vessel segments, CCTA/VIE had sensitivity, specificity, accuracy, positive predictive value, and negative predictive value (shown in %) of 93.9/90.2, 96.2/98.2, 96.0/97.7, 70.0/83.1, and 99.4/99.0, respectively, in diagnosing ISR or CAD, with significantly improved specificity (p = 0.025), accuracy (p = 0.046), and positive predictive value (p = 0.047). VIE can be a helpful addition to CCTA when evaluating coronary arteries.

The usefulness of subtraction coronary computed tomography angiography for in-stent restenosis assessment of patients with CoCr stent using 320-row area detector CT

The aim of this study was to assess in-stent restenosis (ISR) of coronary artery for patients with CoCr stent using subtraction coronary computed tomography angiography (CCTA) with one-breath-hold scan on 320-row area detector CT, invasive coronary angiography (ICA) as clinical standard.Patients who were referred for CCTA from January 2020 to May 2021 were retrospectively analyzed. Pre-contrast and CCTA was performed with dedicated one-breath-hold subtraction scan protocol and post processing to get subtracted-CCTA image without stent. Subjective image qualities and diagnosable rate were analyzed for CCTA and subtracted-CCTA respectively. The ISR degree of each stent was evaluated both on CCTA and subtracted-CCTA images. The receiver-operating characteristic curve with sensitivity, specificity, accuracy of CCTA, and subtracted-CCTA in the diagnosis of ISR were calculated with ICA as reference.Forty patients with 85 CoCr coronary stents of 3 to 3.5 mm diameter with ICA confirmation within 1 month were finally included. Subtracted-CCTA showed more diagnosable segments of stent (91.76% [78/85]) than those of CCTA (50.59% [43/85]) (P < .001). The subjective image quality score of CCTA was 2.23 ± 1.32 while 3.41 ± 0.90 on subtracted-CCTA (P < .001). Both subtracted-CCTA and CCTA showed high consistency with ICA (Kappa = 0.795 and 0.918 respectively). The area under the curve was 0.607 for CCTA and 0.757 for subtracted-CCTA (P < .001) for stent based diagnose, respectively. The sensitivity, specificity, accuracy of CCTA, and subtracted-CCTA were 90.0%, 97.0%, 95.3%, and 87.5%, 100.0%, 97.43%, respectively.Subtracted-CCTA showed improved diagnose performance for ISR, which potentially reduce further follow-up ICA procedures for patients with CoCr stents.

Diagnostic accuracy of dual-source and 320-row computed tomography angiography in detecting coronary in-stent restenosis: a systematic review and meta-analysis

BACKGROUND

Dual-source and 320-row computed tomography angiography (CTA) are increasingly used in diagnosing coronary in-stent restenosis (CISR).

PURPOSE

We sought to perform this meta-analysis to evaluate the diagnostic accuracy of dual-source computed tomography angiography (DSCTA) and 320-row CTA in detecting CISR when compared to invasive coronary angiography.

MATERIAL AND METHODS

Five scientific databases (PubMed, Embase, Scopus, The Cochrane Library, and Web of Science) were searched for research studies in which DSCTA and/or 320-row CTA were used as diagnostic tools for CISR, as recently as October 2017. Study inclusion, data extraction, systematic review, pooled meta-analysis, and subgroup analysis were conducted by two researchers independently.

RESULTS

Thirteen studies with 1384 assessable stents on DSCTA and five studies including 622 assessable stents on 320-row CTA were finally included. The sensitivity, specificity, and area under the curve (AUC) of DSCTA in diagnosing CISR were 0.92 (0.87-0.96), 0.91 (0.87-0.94), and 0.97 (0.95-0.98), respectively, and they were 0.91 (0.82-0.96), 0.95 (0.88-0.98), and 0.96 (0.94-0.97) for 320-row CTA. Subgroup analysis result suggested that DSTCA performed significantly better in CISR detection when the stent diameter was ≥ 3 mm compared to stent diameter < 3 mm: 0.98 (0.97-0.99) vs. 0.82 (0.79-0.86) with P < 0.05.

CONCLUSION

Our meta-analysis indicated both DSCTA and 320-row CTA had high diagnostic accuracy in detecting CISR and may serve as alternatives for further patient evaluation with CISR, especially for stent diameters ≥ 3 mm.

Comparison of the Left Main Coronary Bifurcating Angle among Patients with Normal, Non-significantly and Significantly Stenosed Left Coronary Arteries

We evaluated the correlation of the left main coronary bifurcating angle (LCBA) with the severity of coronary atherosclerosis, risk factors of coronary artery disease (CAD) and the feasibility of measuring the LBCA using the axial plane. Coronary Computed tomography angiographies (CTAs) of 313 patients between Nov. 2006 and Oct. 2013 were reviewed and separated into three groups. Group I (211 patients) had significant stenosis (≥50%) of the left anterior descending coronary artery (LAD) and/or left circumflex coronary artery (LCX). Group II (62 subjects) had atherosclerosis without significant stenosis. Group III (40 subjects) had unremarkable coronary CTAs. Both Group I and II patients received conventional catheter angiography to confirm the severities of coronary stenoses. Significant differences were found among the groups with respect to risk factors, such as male gender, hypertension and body mass index. Axial plane measurement was feasible in most patients (82.1%), without significant differences among the groups. The mean LCBA was 84.7° among all patients, and significantly differed among groups I, II and III (87.34°, 81.16° and 75.53°, P < 0.001). The LCBA of group I was significantly higher than group III (P < 0.001) in univariate analysis, but insignificant in multivariate analysis (P = 0.064).