Diagnostic Accuracy Of Coronary CT Angiography Research Articles

Casting Light on The Hidden Prevalence: A Novel Perspective on Hypoplastic Coronary Artery Disease.

Background and Objectives: Coronary artery anomalies (CAAs) represent a group of rare cardiac abnormalities with an incidence of up to 1.2%. The aim of this retrospective study was to conduct a comprehensive epidemiological assessment of the prevalence of hypoplastic coronary arteries using coronary computed tomography angiography (CCTA) in patients with diagnosed CAAs and individuals presenting with cardiovascular manifestations in the north-eastern region of Romania. This study was motivated by the limited investigation of the CAAs conducted in this area. Methods: We analyzed data collected from 12,758 coronary computed tomography angiography (CCTA) records available at the "Prof. Dr. George I.M. Georgescu" Cardiovascular Diseases Institute, spanning the years 2012 to 2022. Results: Among 350 individuals with CAAs (2.7% of the total cohort), 71 patients (20.3% of the anomaly presenting group and 0.5% of the entire CCTA cohort) exhibited at least one hypoplastic coronary artery. The mean age of individuals diagnosed with hypoplastic coronary artery disease (HCAD) was 61 years, while the age distribution among them ranged from 22 to 84 years. Nearly equal cases of right and left dominance (33 and 31, respectively) were observed, with only 7 cases of co-dominance. Conclusions: HCAD may be considered underexplored in current published research, despite its potentially significant implications ranging to an increased risk of sudden cardiac arrest. The specific prevalence of HCAD among CAAs might be higher than previously reported, possibly reflecting better diagnostic accuracy of CCTA over classic coronary imaging. The absence of standard diagnostic and therapeutic protocols for HCAD underscores the necessity of a personalized approach for such cases.

Diagnostic accuracy of dynamic stress myocardial ct perfusion as compared with invasive coronary physiology assessment in patients with suspected ISR or CAD progression: results of ADVANTAGE II study

Abstract Funding Acknowledgements Type of funding sources: None. Objectives To compare the diagnostic performance of regadenosone-stress dynamic myocardial perfusion assessed by CT (CTP) as compared with that of coronary CT angiography (CCTA) alone by using invasive fractional flow reserve (FFR) and index of microvascular resistance (IMR) as standard of reference. Background Diagnostic performance of CCTA for in-stent restenosis (ISR) detection is still challenging. Recently, CTP demonstrated additional specificity and diagnostic accuracy over CCTA alone in patients with previous stent implantation and suspected IRS or progression of coronary artery disease (CAD). However, no data are available in this clinical setting on the performance of CTP by using a new technique allowing for a non-invasive adjudication of regional myocardial blood flow (Dynamic CTP) and to assess both macrovascular and microvascular disease status. Methods We enrolled consecutive stable patients with previous coronary stenting referred for invasive quantitative coronary angiography (QCA) for clinical indication. All patients underwent dynamic stress myocardial CTP and rest CTP+CCTA by using a last generation scanner characterized by a 16-cm Z-axis coverage and fast (0.28 sec) gantry rotation time. Invasive FFR and IMR were performed during QCA according to the standard practice. The diagnostic rate and diagnostic accuracy of CCTA and CTP were evaluated in a territory-based analyses vs. FFR, IMR (primary endpoint of the study) and QCA (secundary endpoint). Results In 156 enrolled patients (126 men, mean age 63.1±8.2 years), the diagnostic rate (number of territories interpretable/number of territories evaluated) of CTP was significantly higher than that of CCTA (789/799=98.7% vs. 764/799=95.6%; p = 0.0002). The mean absolute MBF values for ischemic territories (pathological FFR and/or IMR) was significantly lower as compared with those for normal territories (96 ± 32 ml/100 g/min vs. 130 ± 46 ml/100 g/min; p< 0.0001). When FFR was used as gold standard, sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of CTP were higher than those of CCTA (89%, 82.8%, 69.2%, 94.6% and 84.7% vs. 60%, 61.9%, 31.9%, 83.8% and 61.5%, p<0.001, respectively). When IMR was used as gold standard, sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of CTP were higher than those of CCTA (76.5%, 85.9%, 72.2%, 88.4% and 82.9% vs. 48.2%, 63.5%, 33.3%, 76.4% and 59.3%, p<0.01, respectively). When the presence of at least one abnormal physiological parameter among FFR and IMR was used as gold standard, the diagnostic accuracy of CTP was higher than that of CCTA (90.8% vs. 68.1%, p<0.001). The mean ED of the total CCTA/rest CTP/stress CTP was 5.63±4.2 mSv. Conclusion In patients with coronary stents, dynamic CTP significantly improves diagnostic rate and accuracy of CCTA alone in comparison with both FFR and IMR.

Diagnostic accuracy of subendocardial vs. transmural myocardial perfusion defect for the detection of in-stent restenosis or progression of coronary artery disease after percutaneous coronary intervention

BackgroundThe ADVANTAGE study demonstrated in a cohort of stented patients a diagnostic accuracy of stress myocardial CT perfusion (CTP) significantly higher than that of coronary CT angiography (CCTA) for the detection of in-stent restenosis (ISR) or CAD progression vs. quantitative coronary angiography (QCA). This is a pre-defined subanalysis of the ADVANTAGE aimed at assessing the difference in terms of diagnostic accuracy vs. QCA of a subendocardial vs. a transmural perfusion defect using static stress CTP. MethodsWe enrolled consecutive patients who previously underwent coronary stenting and were referred for QCA. All patients underwent stress CTP and rest CTP ​+ ​CCTA. The diagnostic accuracy of CCTA and CTP were evaluated in territory-based and patient-based analyses. We compared the diagnostic accuracy of “subendocardial” perfusion defect, defined as hypo-enhancement encompassing >25% but <50% of the transmural myocardial thickness within a specific coronary territory vs. “transmural” perfusion defect, defined as hypo-enhancement encompassing >50% of the transmural thickness. ResultsIn 150 patients (132 men, mean age 65.1 ​± ​9.1 years), the diagnostic accuracy of subendocardial vs. transmural perfusion defect in a vessel-based analysis was 93.5% vs. 87.7%, respectively (p ​< ​0.0001). The sensitivity and specificity of subendocardial vs. transmural defect were 87.9% vs. 46.9% (p ​< ​0.001) and 94.9% vs. 97.9% (p ​= ​0.004), respectively. In a patient-based analysis, the diagnostic accuracy of the subendocardial vs. transmural approach was 86.6% vs. 68% (p ​< ​0.0001). ConclusionsThis study shows that detection of a subendocardial perfusion defect as compared to a transmural defect is significantly more accurate to identify coronary territories with ISR or CAD progression.

The diagnostic accuracy of coronary computed tomography angiography in patients with and without previous coronary interventions

Introduction: Invasive coronary angiography (ICA) is the gold standard for imaging the coronary arteries and the severity of coronary artery disease (CAD). Coronary computed tomography angiography (CCTA) has undergone remarkable progress in the diagnosis of CAD. The study aimed to evaluate the effect of prior versus no previous coronary interventions on the diagnostic accuracy of CCTA as an alternative to ICA to improve health outcomes for patients with suspected CAD.

Change in Computed Tomography-Derived Fractional Flow Reserve Across the Lesion Improve the Diagnostic Performance of Functional Coronary Stenosis.

Aims: This study sought to evaluate the diagnostic performance of change in computed tomography-derived fractional flow reserve (CT-FFR) across the lesion (ΔCT-FFR) for identifying ischemia lesions with FFR as the reference standard.Methods: Patients who underwent coronary CT angiography (CCTA) and FFR measurement within 1 week from December 2018 to December 2019 were retrospectively enrolled. CT-FFR within 2 cm distal to the lesion, ΔCT-FFR and plaque characteristics were analyzed. The diagnostic accuracy of CCTA (coronary stenosis ≥ 50%), CT-FFR ≤ 0.80, and ΔCT-FFR ≥ 0.15 (based on the largest Youden index) were assessed with FFR as the reference standard. The relationship between plaque characteristics and ΔCT-FFR was analyzed.Results: The specificity of ΔCT-FFR and CT-FFR were 70.8 and 67.4%, respectively, which were both higher than CCTA (39.3%) (both P < 0.001), while there were no statistical significance in sensitivity among the three (84.5, 77.4, 88.1%, respectively; P = 0.08). The area under the curves (AUCs) of ΔCT-FFR and CT-FFR were 0.803 and 0.743, respectively, which were both higher than that of CCTA (0.637) (both P < 0.05), and the AUC of ΔCT-FFR was higher than that of CT-FFR (P < 0.001). Multivariable analysis showed that low-attenuation plaque (LAP) volume (odds ratio [OR], 1.006) and plaque length (OR, 1.021) were independently correlated with ΔCT-FFR (both P < 0.05).Conclusions: CT-FFR and ΔCT-FFR and here especially the ΔCT-FFR could improve the diagnostic performance of ischemia compared with CCTA alone. LAP volume and plaque length were the independent risk factors of ΔCT-FFR.

The diagnostic accuracy of coronary computed tomography angiography in patients with and without previous coronary interventions

BackgroundInvasive coronary angiography (ICA) is the gold standard for imaging coronary arteries and the severity of coronary artery disease (CAD). Coronary computed tomography angiography (CCTA) has undergone remarkable progress in the diagnosis of CAD. ObjectivesTo evaluate the effect of prior vs no previous coronary interventions on the diagnostic accuracy of CCTA as an alternative to ICA to improve health outcomes for patients with suspected CAD. MethodsA prospective cohort study was carried out among patients suspected of CAD and for evaluation of grafts and stents to investigate recurrent ischemic symptoms. 120 patients imaged by CCTA were then referred to ICA, which is considered the gold standard. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of CCTA were assessed relative to ICA. ResultsBased on a per-patient analysis, the comparison with ICA reveals variations in sensitivity, specificity, PPV, NPV and accuracy of CCTA. In patients without any previous coronary interventions, the sensitivity was 97.8%, and specificity was 95.6%. The PPV and NPV were 97.8% and 95.5%, respectively. Regarding patients with coronary artery bypass grafts (CABG), the sensitivity was 95% and specificity 100%. The PPV and NPV were 100% and 90.9%, respectively. Regarding patients with prior percutaneous coronary intervention (PCI), the results were a sensitivity of 84.6%, specificity of 77.8%, PPV of 84.6% and NPV of 77.8%. ConclusionCCTA is a powerful diagnostic tool, especially for the evaluation of the major coronary arteries and evaluation of patients with prior CABG. ICA is recommended for evaluation of patients with an intracoronary stent.

185 Diagnostic accuracy of dynamic stress myocardial CT perfusion as compared with invasive coronary physiology metrics in stented patients: preliminary results of the advantage II study

Abstract Aims To compare the diagnostic performance of adenosine-stress dynamic myocardial perfusion assessed by CT (CTP) as compared with that of coronary CT angiography (CCTA) alone by using invasive fractional flow reserve (FFR) and index of microvascular resistance (IMR) as standard of reference. Diagnostic performance of CCTA for in-stent restenosis (ISR) detection is still challenging. Recently, CTP demonstrated additional specificity and diagnostic accuracy over CCTA alone in patients with previous stent implantation and suspected IRS or progression of coronary artery disease (CAD). However, no data are available in this clinical setting on the performance of CTP by using a new technique allowing for a non-invasive adjudication of regional myocardial blood flow (dynamic CTP) and to assess both macrovascular and microvascular disease status. Moreover, dynamic CTP was never compared vs. a comprehensive assessment of invasive coronary physiology (FFR and IMR). Methods and results We enrolled consecutive stable patients with previous coronary stenting referred for invasive coronary angiography (ICA) for clinical indication. All patients underwent dynamic stress myocardial CTP and rest CTP+CCTA by using a last generation scanner characterized by a 16-cm Z-axis coverage and fast (0.28 s) gantry rotation time. Invasive FFR and IMR were performed during ICA according to the standard practice. The diagnostic rate and diagnostic accuracy of CCTA and CTP were evaluated in a territory-based analyses vs. quantitative coronary angiography (QCA), FFR, and IMR. In 67 enrolled patients (55 men, mean age: 63.1 ± 8.2 years), the diagnostic rate (number of territories interpretable/number of territories evaluated) of CTP was significantly higher than that of CCTA (302/307 = 98.4% vs. 290/307 = 94.4%, P = 0.009). The interpretability of the combined CCTA/CTP approach was 99.7% (306/307 territories). When QCA was used as gold standard, CTP diagnostic accuracy was significantly higher than that of CCTA (84.4% vs. 80.1%, P = 0.01). When coronary physiology metrics were used as gold standard, CTP diagnostic accuracy was significantly higher than that of CCTA vs. both FFR (84.3% vs. 72.2%, P = 0.02) and IMR (83.3% vs. 70.2%, P = 0.02). The radiation exposure of CCTA+CTP was 8.7 ± 2.5 mSv. Conclusions In patients with coronary stents, dynamic CTP significantly improves diagnostic rate and accuracy of CCTA alone in comparison with both FFR and IMR. The non-invasive assessment of ISR is still challenging. The comprehensive assessment by cardiac CT provides anatomical combined to functional evaluation of coronary arteries in revascularized patients with good agreement with invasive physiological evaluation.

Coronary computed tomography versus coronary angiography for preoperative coronary assessment before valve surgery

BackgroundConventional coronary angiography (CAG) is currently the gold standard technique for the assessment of coronary arteries prior to cardiac valve surgery. Although CAG is a relatively safe procedure, however, it is still an invasive procedure, and it has potential hazards and complications. Coronary computed tomography angiography (CCTA) is a non-invasive technique that has emerged robustly as an excellent and attractive tool for delineating coronary anatomy. Therefore, we sought to evaluate the accuracy of CCTA when compared with the gold standard CAG in the evaluation of coronary arteries before valve surgery. We screened 111 consecutive patients with VHD undergoing a routine cardiac catheterization for preoperative evaluation of CAD. Fifty patients were eligible and underwent both CAG and CCTA. Significant coronary stenosis was defined as a luminal diameter decrease of ≥ 50%. Additionally, ectasia, calcifications, and congenital coronary anomalies were analyzed. Also, we compared both techniques regarding radiation dose, contrast volume, and complications. Non-evaluable segments were excluded from all levels of analysis. Sixty-one patients were excluded from the study due to various reasons.ResultsAmong the 50 patients of the study population, 27 (54%) were males. The prevalence of significant CAD in the study population was 19.6% according to the patient-based analysis, and CAG could have been avoided in 80.4% of patients with a true-negative CCTA result. Diagnostic accuracy of CCTA for detection of significant stenosis was evaluated regarding sensitivity and specificity, positive predictive value, negative predictive value, and overall accuracy of CCTA, which was 87.5%, 99.6%,87.5%, 99.6%, and 99.2%, respectively, for segmental-based analysis; 86%, 100%, 100%, 99%, and 99%, respectively, for vessel-based analysis; and 77.8%,100%,100%, 94.9%, and 95.7%, respectively, for patient-based analysis. Fewer rates of complications were encountered with CCTA. Additional information obtained like calcifications and congenital anomalies was diagnosed better with CCTA than CAG.ConclusionOwing mainly to its high negative predictive value, a well-performed CCTA exam is an excellent method to rule out coronary artery disease, specially in patients who are not at high risk of atherosclerosis.

Image Quality of Coronary CT Angiography (CCTA) using 640-slice Scanner: Qualitative and Quantitative Assessments of Coronary Arteries Visibility

The purpose of this study was to evaluate the image quality and diagnostic accuracy of coronary computed tomography angiography (CCTA) using 640-slice scanner. Advancement of multidetector computed tomography (MDCT) technology with higher spatial, temporal resolution, and increasing detector array have improved the image quality and diagnostic accuracy of CCTA. A total of 25 patients (12 men and 13 women) underwent CCTA was chosen and data was acquired by 640-slice scanner. All 16 segments of coronary arteries were evaluated by two reviewers using a 4-likert scale for qualitative assessment. In quantitative assessment, the evaluation of 4 main coronary arteries were analysed in terms of signal intensity (SI), image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR). All 25 patients with a mean age of 52.88 ± 14.75 years old and body mass index (BMI) of 24.24 ± 3.28 kg/m 2 were analysed. In qualitative assessment, from the total of 400 segments, 379 segments (95 %) have diagnostic value while 21 segments do not have diagnostic value, which means 5 % artefact was detected. In quantitative assessment, there was no statistical differences in gender, race, and BMI ( p >0.05). Overall evaluation showed that higher SI at the left main artery (LM) at 393.7 ± 47.19. Image noise was higher at right coronary artery (RCA) at 39.01 ± 13.97. SNR and CNR showed higher at left anterior descending (LAD) with 12.73 ± 5.17 and LM 9.14 ± 4.2, respectively. In conclusion, this study indicates that 640-slice MDCT has higher diagnostic value in CCTA examination with 95 % vessel visibility with 5 % artefact detection. Keywords: CCTA, 640-slice scanner, coronary arteries, MDCT DOI: https://doi.org/10.17576/jskm-2020-1802-06

Validation of deep-learning image reconstruction for coronary computed tomography angiography: Impact on noise, image quality and diagnostic accuracy

BackgroundAdvances in image reconstruction are necessary to decrease radiation exposure from coronary CT angiography (CCTA) further, but iterative reconstruction has been shown to degrade image quality at high levels. Deep-learning image reconstruction (DLIR) offers unique opportunities to overcome these limitations. The present study compared the impact of DLIR and adaptive statistical iterative reconstruction-Veo (ASiR-V) on quantitative and qualitative image parameters and the diagnostic accuracy of CCTA using invasive coronary angiography (ICA) as the standard of reference. MethodsThis retrospective study includes 43 patients who underwent clinically indicated CCTA and ICA. Datasets were reconstructed with ASiR-V 70% (using standard [SD] and high-definition [HD] kernels) and with DLIR at different levels (i.e., medium [M] and high [H]). Image noise, image quality, and coronary luminal narrowing were evaluated by three blinded readers. Diagnostic accuracy was compared against ICA. ResultsNoise did not significantly differ between ASiR-V SD and DLIR-M (37 vs. 37 HU, p = 1.000), but was significantly lower in DLIR-H (30 HU, p < 0.001) and higher in ASiR-V HD (53 HU, p < 0.001). Image quality was higher for DLIR-M and DLIR-H (3.4–3.8 and 4.2–4.6) compared to ASiR-V SD and HD (2.1–2.7 and 1.8–2.2; p < 0.001), with DLIR-H yielding the highest image quality. Consistently across readers, no significant differences in sensitivity (88% vs. 92%; p = 0.453), specificity (73% vs. 73%; p = 0.583) and diagnostic accuracy (80% vs. 82%; p = 0.366) were found between ASiR-V HD and DLIR-H. ConclusionDLIR significantly reduces noise in CCTA compared to ASiR-V, while yielding superior image quality at equal diagnostic accuracy.

Effect of a calcium deblooming algorithm on accuracy of coronary computed tomography angiography

BackgroundCoronary artery calcification is a significant contributor to reduced accuracy of coronary computed tomographic angiography (CTA) in the assessment of coronary artery disease severity. The aim of the current study is to assess the impact of a prototype calcium deblooming algorithm on the diagnostic accuracy of CTA. Methods40 patients referred for invasive catheter angiography underwent CTA and invasive catheter angiography. The CTA were reconstructed using a standard soft tissue kernel (CTASTAND) and a deblooming algorithm (CTADEBLOOM). CTA studies were read with and without the deblooming algorithm blinded to the invasive coronary angiogram findings. Sensitivity, specificity, accuracy, positive predictive value and negative predictive value for the detection of stenosis ≥50% or ≥70% were evaluated using quantitative coronary angiography as the reference standard. Image quality was assessed using a 5-point scale, and the presence of image artifact recorded. ResultsAll studies were diagnostic with 548 segments available for evaluation. Image score was 3.64 ± 0.72 with CTADEBLOOM, versus 3.56 ± 0.72 with CTASTAND (p = 0.38). CTADEBLOOM had significantly less calcium blooming artifact than CTASTAND (12.5% vs. 47.5%, p = 0.001). Based on a 50% stenosis threshold for defining significant disease, the Sensitivity/Specificity/PPV/NPV/Accuracy were 65.9/84.9/27.6/96.6/83.4 for CTADEBLOOM and 75.0/81.9/26.6/97.4/81.4 for CTASTAND using a ≥50% threshold. CTADEBLOOM specificity was significantly higher than CTASTAND (84.9% vs. 81.5%, p = 0.03), with no difference between the algorithms in sensitivity (p = 0.22), or accuracy (p = 0.15). These results remained unchanged when a stenosis threshold of ≥70% was used. Interobserver agreement was fair with both techniques (CTADEBLOOM k = 0.38, CTASTAND k = 0.37). ConclusionIn this proof of concept study, coronary calcification deblooming using a prototype post-processing algorithm is feasible and reduces calcium blooming with an improvement of the specificity of the CTA exam.

Rationale and design of advantage (additional diagnostic value of CT perfusion over coronary CT angiography in stented patients with suspected in-stent restenosis or coronary artery disease progression) prospective study

BackgroundRecent studies demonstrated a significant improvement in the diagnostic performance of coronary CT angiography (CCTA) for the evaluation of in-stent restenosis (ISR). However, coronary stent assessment is still challenging, especially because of beam-hardening artifacts due to metallic stent struts and high atherosclerotic burden of non-stented segments. Adenosine-stress myocardial perfusion assessed by CT (CTP) recently demonstrated to be a feasible and accurate tool for evaluating the functional significance of coronary stenoses in patients with suspected coronary artery disease (CAD). Yet, scarce data are available on the performance of CTP in patients with previous stent implantation. Aim of the studyWe aim to assess the diagnostic performance of CCTA alone, CTP alone and CCTA plus CTP performed with a new scanner generation using quantitative invasive coronary angiography (ICA) and invasive fractional flow reserve (FFR) as standard of reference. MethodsWe will enroll 300 consecutive patients with previous stent implantation, referred for non-emergent and clinically indicated invasive coronary angiography (ICA) due to suspected ISR or progression of CAD in native coronary segments. All patients will be subjected to stress myocardial CTP and a rest CCTA. The first 150 subjects will undergo static CTP scan, while the following 150 patients will undergo dynamic CTP scan. Measurement of invasive FFR will be performed during ICA when clinically indicated. ResultsThe primary study end points will be: 1) assessment of the diagnostic performance (diagnostic rate, sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy) of CCTA, CTP, combined CCTA-CTP and concordant CCTA-CTP vs. ICA as standard of reference in a territory-based and patient-based analysis; 2) assessment of sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of CCTA, CTP, combined CCTA-CTP and concordant CCTA-CTP vs. invasive FFR as standard of reference in a territory-based analysis. ConclusionsThe ADVANTAGE study aims to provide an answer to the intriguing question whether the combined anatomical and functional assessment with CCTA plus CTP may have higher diagnostic performance as compared to CCTA alone in identifying stented patients with significant ISR or CAD progression.

Diagnostic performance of coronary CT angiography carried out with a novel whole-heart coverage high-definition CT scanner in patients with high heart rate

BackgroundAim of the study was to evaluate image quality, radiation exposure and diagnostic accuracy of coronary CT angiography (CCTA) performed with a novel cardiac CT scanner in patients with very high heart rate (HR). MethodsWe prospectively enrolled 202 patients (111 men, mean age 66±8years) with suspected coronary artery disease who underwent CCTA with a whole-organ volumetric CT scanner. The HR during the scan was ≥80bpm in 100 patients (Group 1), while it was ≤65bpm in the remaining 102 patients (Group 2). In all patients, image quality score and coronary interpretability were evaluated and effective dose (ED) was recorded. In 86 of the 202 enrolled patients (40 patients in Group 1, 46 patients in Group 2) who were referred for a clinically indicated invasive coronary angiography (ICA) within 6months, diagnostic accuracy of CCTA vs. ICA was evaluated. ResultsMean image quality and coronary interpretability were very high in both Groups (Likert=3.35 vs. 3.39 and 97.3% [1542/1584 segments] and 98% [1569/1600 segments] in Group 1 and Group 2, respectively). Mean ED was lower in Group 2 (1.1±0.5mSv) compared to Group 1 (2.9±1.6mSv). In Group 1, sensitivity and specificity of CCTA for detection of >50% stenosis vs. ICA were 95.2% and 98.9% in a segment-based analysis and 100% and 81.8% in a patient-based analysis, respectively. ConclusionsThe whole organ high-definition CT scanner allows evaluating coronary arteries in patients with high HR with excellent image quality, coronary interpretability and low radiation exposure.

Low- to high-density lipoprotein cholesterol ratio followed by coronary computed tomography angiography improves coronary plaque classification accuracy.

Coronary computed tomography angiography (CCTA) is a noninvasive test for detection and analysis of coronary plaques morphology and classification. The low- to high-density lipoprotein cholesterol (L/H) ratio is associated with plaques vulnerability. The study aims to investigate the diagnostic accuracy of CCTA and L/H ratio for plaques classification. We enrolled 212 patients with coronary artery single-vessel disease who performed preoperative CCTA and Intravascular ultrasound (IVUS)-guided invasive coronary angiography. Patients were assigned to the acute coronary syndrome (ACS) group (n = 129) and stable angina pectoris (SAP) group (n = 83). CCTA showed that patients with ACS had more soft plaque and less calcific plaque than those with SAP. The plaque volume and remodeling index measured by CCTA showed good correlation with those measured by IVUS. IVUS identified 91 soft, 58 mixed and 63 calcific plaques in this cohort. For diagnosis of noncalcified plaque (soft and mixed), CCTA had the sensitivity and specificity of 87.9% and 90.4%, respectively. While refer to the further diagnosis of mixed plaque from noncalcified plaque, the sensitivity and specificity was 88.4% and 88.8%, respectively. The L/H ratio was gradually decreased from soft plaque to calcific plaque. If the patients had both the two characteristics (L/H ≥ 2.55 and CCTA), the sensitivity, and specificity were improved in diagnosing noncalcified plaque or mixed plaque. In conclusion, a combined application of CCTA and L/H ratio improves the diagnostic accuracy for coronary noncalcified plaque or mixed plaque as compared to CCTA along.

Submillisievert imaging protocol using full reconstruction and advanced patient motion correction in 320-row area detector coronary CT angiography.

Radiation exposure remains a concern in the use of coronary CT angiography (CCTA). Full reconstruction (Full) and reconstruction using advanced patient motion correction (APMC) could obtain a lower radiation dose using low tube current scanning in a 320-row Area Detector CT (320-ADCT). The radiation dose for an imaging protocol using Full and APMC in daily practice was estimated. A total of 209 patients who underwent CCTA in 1 rotation scanning with 100 kv and adaptive iterative dose reduction 3D in 320-ADCT were enrolled. Imaging protocols were classified into 3 groups based on estimated slow filling time: (1) slow filling time ≥ 275 msec, Full with 30% of usual tube current (N = 43)(Full30%mA) (2) 206.3 msec ≤ slow filling time < 275msec, APMC with 50% of usual tube current (N = 48)(APMC50%mA); and (3) 137.5msec ≤ slow filling time < 206.3msec, Half reconstruction with usual tube current (N = 118)(Half100%mA). Radiation dose was estimated by the effective dose. The diagnostic accuracy of CCTA was compared with that of invasive coronary angiography in 28 patients. The effective doses of Full30%mA, APMC50%mA, and Half100%mA were 0.77 ± 0.31, 1.30 ± 0.85, and 1.98 ± 0.68, respectively. Of 28 patients, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value in vessel-based analyses were: Full30%mA, 66.7, 82.4, 80.0, 40.0, and 93.3%; APMC50%mA, 100.0, 80.0, 83.3, 50.05, and 100.0%; and Half100%mA, 90.9, 83.0, 86.3, 78.95, and 92.9%, respectively. An imaging protocol using Full30%mA and APMC50%mA was one of the methods how radiation dose could be reduced radiation dose maintained diagnostic accuracy compared to imaging using conventional Half100%mA.

Coronary CT angiography with 80 kV tube voltage and low iodine concentration contrast agent in patients with low body weight

BackgroundCoronary CT angiography (CTA) is gaining widespread acceptance for the non-invasive evaluation of coronary arteries. However, radiation exposure and administration of iodinated contrast agents are still reasons of some concern. The 80 kV tube voltage increases the attenuation of iodine, allowing to use lower iodine concentration contrast agents for coronary CTA. ObjectiveWe evaluated the diagnostic accuracy of coronary CTA performed with 64-slice scanner, 80 kV tube voltage, iterative reconstruction algorithm and ultra-low concentration contrast medium to reduce iodine load and radiation dose. MethodsWe enrolled 45 patients with low body weight and indication for elective invasive coronary angiography (ICA). All patients received an 80 ml bolus of Iodixanol-270 at an infusion rate of 5 mL/s and underwent coronary CTA (80 kV and 500–550 mA) with prospective ECG-triggering. Image quality score, type of artifacts, coronary CTA evaluability, diagnostic accuracy and radiation exposure were assessed. ResultsPre-test probability of CAD was low-to-intermediate (48%). Accordingly, the prevalence of obstructive CAD was 47% (21 out of 45 patients). Most (93%) of the patients were pre-treated with intravenous metoprolol before scanning and achieved a heart rate suitable for prospective ECG-triggering coronary CTA (53 ± 3 bpm). The mean effective dose and iodine load were 1.1 ± 0.4 mSv and 21.6 gI, respectively. We rated 443 out of 720 coronary segments as being of excellent image quality. In a segment-based model, coronary evaluability (number of coronary segments evaluable/total number of coronary segments), was 97% (699/720 segments). In a segment-based analysis, sensitivity, specificity, positive predictive value, negative predictive value and accuracy for >50% coronary stenosis identification vs. ICA were 89%, 99%, 89%, 99% and 99%, respectively. In a patient-based analysis, sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 94%, 89%, 83%, 96% and 91%, respectively. ConclusionsIn patients with low body weight, image quality and diagnostic accuracy of ultra-low radiation dose and low-iodine load coronary CTA are good and similar to values reported in the literature for standard tube voltage and iodine load protocols.

The Emerging Roles of Coronary Computed Tomographic Angiography: Acute Chest Pain Evaluation and Screening for Asymptomatic Individuals.

Coronary computed tomographic angiography (CCTA) has been widely available since 2004. After that, the diagnostic accuracy of CCTA has been extensively validated with invasive coronary angiography for detection of coronary arterial stenosis. In this paper, we reviewed the updated evidence of the role of CCTA in both scenarios including acute chest pain and screening in asymptomatic adults. Several large-scale studies have been conducted to evaluate the diagnostic value of CCTA in the context of acute chest pain patients. CCTA could play a role in delivering more efficient care. For risk stratification of asymptomatic patients using CCTA, latest studies have revealed incremental benefits. Future studies evaluating the totality of plaque characteristics may be useful for determining the role of noncalcified plaque for risk stratification in asymptomatic individuals. Acute chest pain • Computed tomography • Coronary artery disease • Health screening • Stable angina.

Transluminal attenuation gradient in coronary computed tomography angiography for determining stenosis severity of calcified coronary artery: a primary study with dual-source CT.

To evaluate the diagnostic accuracy of transluminal attenuation gradient (TAG) for stenosis severity of calcified lesions assessed by coronary computed tomography angiography (CCTA). One hundred seven patients who underwent CCTA and coronary angiography (CAG) were enrolled. TAGs of 309 major epicardial coronary arteries were measured. The impact of plaque composition, Agatston scores, and lesion length ratio on TAG were analyzed. Diagnostic performance vs. CAG of TAG, CCTA, and combined TAG/CCTA were evaluated, and incremental value of TAG for reclassification of CCTA stenosis severity in calcified lesions was also analyzed. TAG decreased consistently with stenosis severity. TAG was significantly lower in coronary arteries with calcification scores >300 and lesion length ratios >2/3. TAG improved diagnostic accuracy of CCTA (c-statistic =0.982 vs. 0.942, P = 0.0001) in calcified lesions, and the sensitivity, specificity, positive, and negative predictive values of TAG cutoff ≤ -11.33 were 72 %, 91 %, 88 %, and 78 %, respectively. The addition of TAG to CCTA resulted in significant reclassification (NRI =0.093, P = 0.022) in calcified vessels. Measurement of TAG may improve diagnostic performance and reclassification of CCTA in coronary stenosis caused by calcified lesions. • TAG decreased as calcification scores and lesion length increased. • TAG markedly improved the diagnostic performance of CCTA for calcified lesions. • TAG improved reclassification of coronary artery stenosis severity in CCTA.

Abstract 18795: Resting Patient- and Vessel-Specific Myocardial Perfusion Attenuation Patterns Improves Diagnostic Performance of Coronary Computed Tomographic Angiography

Introduction: Coronary CT angiography (CCTA) demonstrates improved performance for diagnosis of high-grade coronary stenoses, but may be affected by artifacts and overestimation of stenosis severity. Whether the addition of resting myocardial perfusion attenuation patterns subtended by stenosis seen on CCTA improves diagnostic performance has not been examined to date. Methods: We evaluated 127 patients (mean age 53.0, 54.3% male) who underwent CCTA and ICA. Percentage of coronary stenosis was assessed by quantitative coronary angiography (QCA), which served as the reference comparator to CCTA. CCTA stenosis was categorized as 0%, 1-24%, 25-49%, 50-69%, 70-99%, and 100% luminal diameter reduction. Automated software (SmartHeart, Redwood City, CA) was used to measure resting CT perfusion attenuation patterns in myocardial segments by AHA 17-segment model. Segmental CT attenuation values were assigned to territories subtended by left anterior descending (LAD), left circumflex (LCX), and right coronary arteries (RCA). Per-patient and per-vessel analyses were based on highest severity (maximal stenosis, minimal attenuation). On both per-patient and per-vessel basis, logistic regression was devised for CCTA stenosis alone and for CCTA plus resting myocardial attenuation. Diagnostic accuracy and area under the receiver operating characteristics curve (AUC) were determined. Results: Diagnostic accuracy of CCTA alone was 84.0%, 85.5%, 90.4%, and 88.6%, at per-patient, per-LAD, per-LCX and per-RCA level, respectively. In comparison, the accuracy of CCTA plus myocardial attenuation were 89.6%, 91.9%, 95.2%, and 92.7%. The AUCs using CCTA alone to discriminate QCA-confirmed coronary stenoses &gt;70% were 0.823 (95% CI: 0.737-0.909), 0.782 (95% CI: 0.667-0.898), 0.690 (95% CI: 0.503-0.878), and 0.793 (95% CI: 0.640-0.945) for per-patient, per-LAD, per-LCX, and per-RCA analysis, respectively. The AUCs using CCTA plus myocardial attenuation improved to 0.864 (95% CI: 0.765-0.962), 0.881 (95% CI: 0.793-0.968), 0.772 (95% CI: 0.535-1.000), and 0.820 (95% CI: 0.685-0.954). Conclusions: The addition of resting CT myocardial perfusion attenuation patterns improves identification and discrimination of high-grade coronary stenosis by CCTA.

Recent improvement in coronary computed tomography angiography diagnostic accuracy.

Although invasive coronary angiography has been the gold standard for evaluating coronary artery disease (CAD), it should not be routinely performed as an initial test to assess CAD in subjects with suspected CAD by the recent guidelines, due to cost, invasiveness, and measurable risk. Coronary computed tomography angiography (CCTA) is a rapidly growing, noninvasive imaging modality that developed quickly over the last decade, and its role for evaluation of CAD becomes of great promise with high diagnostic accuracy. Although artifact issues have created some challenges for CCTA, recent advances-including the introduction of more detectors, leading to broader coverage, and faster and higher-definition scanners-allow improved precision and fewer uninterpretable studies. This review article summarizes the current key literature regarding the diagnostic accuracy of CCTA in native coronary arteries, stents, coronary artery bypass grafts, lesions with high calcification, and the functional assessment of CAD.