Subsequent Invasive Coronary Angiography Research Articles

[15O]H2O myocardial perfusion positron emission tomography: Added value of relative stress perfusion deficit in the prediction of significant coronary artery stenosis in a mixedpopulation

BackgroundIt remains unknown whether estimation of the relative stress perfusion deficit offers added value in the prediction of significant coronary artery stenosis in myocardial perfusion imaging with [15O]H2O positron emission tomography (PET) in a population with high prevalence of established cardiac disease. MethodsDuring eight months, we consecutively included all patients undergoing [15O]H2O PET and subsequent invasive coronary angiography (ICA). Significant stenosis was defined from ICA as fractional flow reserve ≤.8 or coronary artery narrowing of ≥70%. We calculated absolute and relative total perfusion deficits (aTPD and rTPD, respectively) as semiquantitative measures of the extent and severity of reduced stress perfusion. A multivariate logistic regression analysis was performed to test the adjusted associations (odds ratio (OR) with 95% CI) with significant coronary artery stenosis. ResultsOf 800 patients undergoing [15O]H2O PET, 144 underwent ICA, where 142 patients had aTPD of ≥3% and 79 (55%) of these had at least one significant stenosis. In an adjusted analysis, rTPD (OR10% increase = 2.12 (1.44-3.12), P < .001), previous coronary artery bypass grafting (CABG) (OR = .11 (.03-.36), P < .001) and reduced left ventricular ejection fraction (LVEF) (OR = .25 (.08-.84), P = .02) were independently associated with significant stenosis, whereas the association with aTPD (OR10% increase = 1.14 (.98-1.32), P = .08) was modest. ConclusionsIn the presence of an absolute perfusion deficit (aTPD of ≥3%), rTPD may improve the prediction of significant stenosis in a heterogeneous population of patients examined with [15O]H2O PET. Furthermore, previous CABG and reduced LVEF are associated with nonstenotic perfusion deficiencies, suggesting caution when interpreting myocardial perfusion imaging in such patients.

Super-resolution deep learning reconstruction to improve image quality of coronary CT angiography

Abstract Purpose To compare the objective and subjective image quality and diagnostic performance for coronary stenosis of normal-dose model-based iterative reconstruction and reduced-dose super-resolution deep learning reconstruction in coronary CT angiography. Materials and Methods This single-center retrospective study included 52 patients (mean age, 68 years ± 10 [SD]; 41 men) who underwent serial coronary CT angiography and subsequent invasive coronary angiography between January and November 2022. The first 25 patients were scanned with a standard dose using model-based iterative reconstruction. The last 27 patients were scanned with a reduced dose using super-resolution deep learning reconstruction. Per-patient objective and subjective image qualities were compared. Diagnostic performance of model-based iterative reconstruction and super-resolution deep learning reconstruction to diagnose significant stenosis on coronary angiography was compared per-vessel using receiver operating characteristics curve analysis. Results The median tube current of super-resolution deep learning reconstruction was lower than that of model-based iterative reconstruction (median [IQR], 890 mA [680, 900] vs. 900 mA [895, 900], P = 0.03). Image noise of super-resolution deep learning reconstruction was lower than that of model-based iterative reconstruction (14.6 Hounsfield units ± 1.3 vs. 22.7 Hounsfield units ± 4.4, P &amp;lt; .001). Super-resolution deep learning reconstruction improved the overall subjective image quality compared with model-based iterative reconstruction (median [IQR], 4 [3, 4] vs 3 [3, 3], P = .006). No difference in the area under the receiver operating characteristic curve in diagnosing coronary stenosis using super-resolution deep learning reconstruction (0.96; 95% CI, 0.92-0.99) and model-based iterative reconstruction (0.96; 95% CI, 0.92-0.98; P = .98) was observed. Conclusion Our exploratory analysis suggests that super-resolution deep learning reconstruction could improve image quality with lower tube current settings than model-based iterative reconstruction with similar diagnostic performance to diagnose coronary stenosis in coronary CT angiography.

Association Between Red Blood Cell Distribution Width and Coronary Calcification in Patients Referred for Invasive Coronary Angiography.

This study aimed to determine whether red cell distribution width (RDW) is associated with coronary calcification. A total of 4796 patients who underwent coronary computed tomography angiography and subsequent invasive coronary angiography were consecutively enrolled. Coronary artery calcium score (CACS), demographic, clinical, and laboratory data were collected from electronic medical records. RDW were expressed in two forms, as a coefficient of variation (CV) or as a standard deviation (SD). Multivariable ordinal logistic regression was used to investigate the association of RDW with CACS grades (CACS 0-99, 100-399, 400-999, and >1000). A significant association was found between elevated RDW-SD and higher CACS grades after full adjustment (adjusted OR per 1-SD increase: 1.11, 95% CI: 1.05-1.18; P < .001), while no significant association was found between RDW-CV and CACS grades. When RDW-SD was analyzed as a categorical variable, it was primarily the 4th quartile of RDW-SD that was associated with elevated CACS grades compared with the 1st quartile (adjusted OR: 1.25, 95% CI: 1.07-1.46; P = .006), while the 2nd and 3rd quartiles showed no significantly higher risk. RDW-SD is a more robust biomarker for coronary calcification compared with RDW-CV.

Photon-counting detector CT reduces the rate of referrals to invasive coronary angiography as compared to CT with whole heart coverage energy-integrating detector

BackgroundWe sought to compare the degree of maximal stenosis and the rate of invasive coronary angiography (ICA) recommendations in patients who underwent coronary CT angiography (CCTA) with photon-counting detector CT (PCD-CT) versus those who underwent CCTA with whole heart coverage energy-integrating detector CT (EID-CT). MethodsIn our retrospective single-center study, we included consecutive patients with suspected CAD who underwent CCTA performed with either PCD-CT or a 280-slice EID-CT. The degree of coronary stenosis was classified as no CAD, minimal (1–24 ​%), mild (25–49 ​%), moderate (50–69 ​%), severe stenosis (70–99 ​%), or occlusion. ResultsA total of 812 consecutive patients were included in the analysis, 401 patients scanned with EID-CT and 411 patients with PCD-CT (mean age: 58.4 ​± ​12.4 years, 45.4 ​% female). Despite the higher total coronary artery calcium score (CACS) in the PCD-CT group (10 [interquartile range (IQR) ​= ​0–152.8] vs 1 [IQR ​= ​0–94], p ​< ​0.001), obstructive CAD was more frequently reported in the EID-CT vs PCD-CT group (no CAD: 28.7 ​% vs 26.0 ​%, minimal: 23.2 ​% vs 30.9 ​%, mild: 19.7 ​% vs 23.4 ​%, moderate: 14.5 ​% vs 9.7 ​%, severe: 11.5 ​% vs 8.5 ​% and occlusion: 2.5 ​% vs 1.5 ​%, respectively, p ​= ​0.025). EID-CT was independently associated with downstream ICA (OR ​= ​2.76 [95%CI ​= ​1.58–4.97] p ​< ​0.001) in the overall patient population, in patients with CACS<400 (OR ​= ​2.18 [95%CI ​= ​1.13–4.39] p ​= ​0.024) and in patients with CACS≥400 (OR ​= ​3.83 [95%CI ​= ​1.42–11.05] p ​= ​0.010). ConclusionIn patients who underwent CCTA with PCD-CT the number of subsequent ICAs was lower as compared to patients who were scanned with EID-CT. This difference was greater in patients with extensive coronary calcification.

Abstract 18188: Positron Emission Tomography Has Robust Negative Predictive Value for Development of Clinically Significant Cardiac Allograft Vasculopathy Over Time

Introduction: Cardiac allograft vasculopathy (CAV) affects &gt;50% of OHT recipients by 10 years and is a leading cause of mortality. Standard CAV screening is via invasive coronary angiography (ICA). Recently it has been shown that PET with myocardial blood flow (PET/MBF) has excellent diagnostic ability for CAV, however, its prognostic value is not known. Hypothesis: CAV assessment by PET/MBF can prognosticate lack of significant angiographic progression of CAV over meaningful time scales. Methods: A retrospective analysis of 206 OHT recipients who underwent a PET/CT between ICAs was performed. CAV progression over time was assessed using intra-patient sequences of 1) baseline ICA, 2) interval PET, and 3) subsequent ICA. PET CAV grades were determined using the algorithm in Table 1. For each interval, NPV of CAV development was calculated. Results: Intervals between ICAs of 600, 800, 1000, and 1200 days were included with 77, 114, 106, and 22 patients respectively. Sequences were analyzed if the PET fell within middle third of interval. For development of ISHLT CAV 2/3 on subsequent ICA, PET CAV 0/1 had an NPV of 0.91, 0.94, 0.91, and 0.86 at each respective time point. For development of meaningful ISHLT CAV (presence of ≥ 30% vessel stenosis) on subsequent ICA, PET CAV 0/1 had an NPV of 0.80, 0.85, 0.85, 0.8 respectively (Figure 1). Conclusions: Non-invasive CAV assessment by PET/MBF provides robust NPV for development of varying degrees of clinically significant CAV over intervals up to 4 years. PET may be used as an adjunct to ICA for CAV screening and is a viable alternative among those with reasonable risk profiles. Prospective studies are needed to determine optimal interval lengths.

Incremental value of computed tomography angiographic derived fractional flow reserve in patients with stable chest pain and anatomical obstructive coronary artery disease

Abstract Funding Acknowledgements Type of funding sources: None. Background Coronary computed tomography angiography (CCTA)-derived fractional flow reserve (FFRCT) is endorsed by guidelines for the evaluation of obstructive coronary artery disease (OCAD) (1). However, real-world impact of selective use of FFRCT in patients with suspected OCAD by CCTA on subsequent invasive coronary angiography (ICA) and revascularization remains unclear. Purpose To assess the impact and diagnostic accuracy of FFRCT interpretation in patients with suspected OCAD by CCTA on downstream ICA and revascularization. Methods All consecutive patients who underwent coronary CCTA for the evaluation of stable chest pain between 01/10/2013 and 28/05/2021 in our tertiary university hospital were included in a registry. From a total population of 7541 patients, 1601 with reported anatomical obstructive OCAD on CCTA, were included in our study. OCAD was defined as the presence of a stenosis ≥ 50% in at least one of the three main vessels. CCTA were selectively send to FFRCT analysis according to radiologist's decision. A numerical interpretation of FFRCT was firstly performed by defining a lowest distal value≤ 0.8 as a possible need for revascularization and secondly, a comprehensive interpretation of FFRCT was completed by an experienced interventional cardiologist and radiologist. In brief, this interpretation takes into account not only the lowest distal FFRCT value, but also the post-stenotic FFR, the trans-lesional gradient and anatomical distribution of FFRCT changes. Results From a registry of 7541 patients, suspected OCAD derived from CCTA was reported in 1601 cases, including 808 (50.5%) patients evaluated by FFRCT. ICA was performed in 1160 (72.5%) and revascularization in 559 (34.9%) patients. Overall proportion of ICA decreased from 77.2 to 67.8% with FFRCT use (chi² p&amp;lt;0.01) (Figure 1). After propensity score weighting, FFRCT use was independently associated with decreased ICA (OR: 0.66; 95% CI 0.53–0.83, p&amp;lt; 0.001) and with a decreased rate of myocardial revascularization (OR: 0.71; 95% CI 0.58 –0.88, p&amp;lt; 0.01). Compared to a numerical interpretation, a comprehensive assessment of FFRCT increased the ratio of revascularization per ICA (61.8 vs 50.2 %, p&amp;lt; 0.01) and was more accurate to rule-in OCAD patient requiring a myocardial revascularization (Figure 2). After propensity score adjustment, numerically abnormal FFRCT and pathological coronary disease distribution on comprehensive assessment similar were still independently associated with an increased the rate of ICA use (OR:3.03 95% CI 2.18–4.23, p&amp;lt; 0.001 and OR: 3.45; 95% CI 2.47–4.82, p&amp;lt; 0.001, respectively) and myocardial revascularization (OR:5.13; 95% CI 3.23–8.15, p&amp;lt; 0.001 and OR:6.48; 95% CI 4.55–9.22, p&amp;lt; 0.001, respectively). Conclusion We observed in a large single-center real-world registry that implementing FFRCT downstream ICA and that a comprehensive assessment of FFRCT ensures an improved selection of patients requiring myocardial revascularization.

Validation of coronary CTA based-British cardiovascular intervention society Jeopardy score (CT-BCIS-JS) against invasive BCIS-JS - a feasibility and reproducibility study

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Promedica Stiftung and the Iten-Kohaut Foundation in collaboration with the USZ Foundation Background/Introduction The invasive British Cardiovascular Intervention Society Jeopardy Score (iBCIS-JS) is a simple angiographic scoring system, enabling quantification of the extent of jeopardized myocardium related to clinically significant coronary artery disease (CAD). Ranging from 0 (no significant CAD) to 12 (CAD jeopardizing the whole LV- myocardium), the score is used for the entire spectrum of CAD including left main coronary artery and coronary artery bypass graft disease. A score of ≥6 identifies patients with anatomically high-risk CAD. Non-invasive CAD assessment with coronary CTA is hampered by modest specificity, leading potentially to increased utilization of downstream diagnostic tests. Purpose To validate coronary CTA-based assessment of the BCIS-JS (CT-BCIS-JS) against the iBCIS-JS and to assess its feasibility and reproducibility. Methods A total of 137 patients who underwent clinically indicated coronary CTA and subsequent invasive coronary angiography within 90 days were included in the analysis. Eleven patients were excluded due to suboptimal CTA image quality. CT-BCIS-JS and iBCIS-JS were calculated. Correlations were assessed with the Spearman’s rank correlation coefficient and agreement between scores with Bland-Altman (BA) analysis and with weighted kappa statistics. Inter-observer variability was investigated in a subset of 51 randomly selected patients. Results Median and interquartile range (IQR) of CT-BCIS-JS was 4 (IQR=8) and of iBCIS-JS 4 (IQR=8) (Figure 1). A CT-BCIS-JS of ≥6 and was observed in 56 (44%) patients and an iBCIS-JS of ≥6 in 54 patients (43%). An excellent correlation between the iBCIS-JS and the CT-BCIS-JS was observed (rho=0.97, p&amp;lt;0.0001; Figure 2A) with high agreement (BA bias 0.1 and limits of agreement −2.0 to 2.2; Figure 2B). Kappa analysis demonstrated excellent aagreement for identification of a iBCIS-JS of ≥6 (Kappa Weighted= 0.94, 95% CI 0.87–0.99). Inter-observer analysis revealed excellent correlation (rho=0.98, p&amp;lt;0.0001) and agreement (BA bias 0.12 and limits of agreement −1.33 to 1.57). Conclusions The CT-BCIS-JC represents a feasible and highly reproducible tool for accurate, non-invasive identification of patients with anatomically high-risk CAD. Hence, the CT-BCIS-JC may serve as reliable gatekeeper for invasive testing in the management of patients with CAD.

Epicardial adipose tissue and obstructive coronary artery disease in acute chest pain: the EPIC-ACS study.

We tested the hypothesis that epicardial adipose tissue (EAT) quantification improves the prediction of the presence of obstructive coronary artery disease (CAD) in patients presenting with acute chest pain to the emergency department. Within this prospective observational cohort study, we included 657 consecutive patients (mean age 58.06 ± 18.04 years, 53% male) presenting to the emergency department with acute chest pain suggestive of acute coronary syndrome between December 2018 and August 2020. Patients with ST-elevation myocardial infarction, haemodynamic instability, or known CAD were excluded. As part of the initial workup, we performed bedside echocardiography for quantification of EAT thickness by a dedicated study physician, blinded to all patient characteristics. Treating physicians remained unaware of the results of the EAT assessment. The primary endpoint was defined as the presence of obstructive CAD, as detected in subsequent invasive coronary angiography. Patients reaching the primary endpoint had significantly more EAT than patients without obstructive CAD (7.90 ± 2.56 mm vs. 3.96 ± 1.91 mm, P < 0.0001). In a multivariable regression analysis, a 1 mm increase in EAT thickness was associated with a nearby two-fold increased odds of the presence of obstructive CAD [1.87 (1.64-2.12), P < 0.0001]. Adding EAT to a multivariable model of the GRACE score, cardiac biomarkers and traditional risk factors significantly improved the area under the receiver operating characteristic curve (0.759-0.901, P < 0.0001). Epicardial adipose tissue strongly and independently predicts the presence of obstructive CAD in patients presenting with acute chest pain to the emergency department. Our results suggest that the assessment of EAT may improve diagnostic algorithms of patients with acute chest pain.

Clinical outcomes of a CT protocol for simultaneous examination of the aorta and coronary artery in patients with aortic aneurysm.

In patients with aortic aneurysm (AA), coronary artery disease (CAD) increases the risk of perioperative complications and even asymptomatic CAD isassociated with adverse clinical outcomes. We aimed to compare coronary-aorta CT (CACT) with thoracoabdominal CT angiography (Aorta CT) for CAD management and clinical outcomes in these patients. We enrolled 479 patients undergoing CACT and 693 patients undergoing Aorta CT as an initial CT scan for AA. The primary outcome was a composite of all-cause death or myocardial infarction (MI) at 3 years after CT. The secondary outcomes were subsequent CAD management and invasive coronary angiography (CAG). After index CT scan, the CACT group had a significantly higher rate of coronary revascularization compared with the Aorta CT group (10.7% vs. 3.8%, p < 0.001) but a lower probability of diagnostic CAG among total invasive CAG (32% vs. 55%, p < 0.001). At 3 months after the CT scan, the prescription rates of statins (65.8% vs. 44.6%, p < 0.001) and antiplatelet agents (57.6% vs. 43.9%, p < 0.001) were higher in the CACT group. During follow-up, the CACT group had a significantly lower incidence of the composite outcome of all-cause death or MI (adjusted HR 1.72, 95% CI 1.07-2.78, p = 0.027) than the Aorta CT group. Among patients with AA, CACT was associated with a higher rate of subsequent CAD management and a lower risk of all-cause death or MI compared to Aorta CT. When evaluating with AA using CT, simultaneous coronary and aortic evaluation using CACT would be recommended over Aorta CT.

Likelihood reclassification by an acoustic-based score in suspected coronary artery disease

ObjectiveValidation studies of the 2019 European Society of Cardiology pretest probability model (ESC-PTP) for coronary artery disease (CAD) report that 35%–40% of patients have low pretest probability (ESC-PTP 5% to...

Second-Line Myocardial Perfusion Imaging to Detect Obstructive Stenosis: Head-to-Head Comparison of CMR and PET

BackgroundGuidelines recommend verification of myocardial ischemia by selective second-line myocardial perfusion imaging (MPI) following a coronary computed tomography angiography (CTA) with suspected obstructive coronary artery disease (CAD). Head-to-head data on the diagnostic performance of different MPI modalities in this setting are sparse. ObjectivesThe authors sought to compare, head-to-head, the diagnostic performance of selective MPI by 3.0-T cardiac magnetic resonance (CMR) and 82rubidium positron emission tomography (RbPET) in patients with suspected obstructive stenosis at coronary CTA using invasive coronary angiography (ICA) with fractional flow reserve (FFR) as reference. MethodsConsecutive patients (n = 1,732, mean age: 59.1 ± 9.5 years, 57.2% men) referred for coronary CTA with symptoms suggestive of obstructive CAD were included. Patients with suspected stenosis were referred for both CMR and RbPET and subsequently ICA. Obstructive CAD was defined as FFR ≤0.80 or >90% diameter stenosis by visual assessment. ResultsIn total, 445 patients had suspected stenosis on coronary CTA. Of these, 372 patients completed both CMR, RbPET and subsequent ICA with FFR. Hemodynamically obstructive CAD was identified in 164 of 372 (44.1%) patients. Sensitivities for CMR and RbPET were 59% (95% CI: 51%-67%) and 64% (95% CI: 56%-71%); P = 0.21, respectively, and specificities 84% (95% CI: 78%-89%) and 89% (95% CI: 84%-93%]); P = 0.08, respectively. Overall accuracy was higher for RbPET compared with CMR (73% vs 78%; P = 0.03). ConclusionsIn patients with suspected obstructive stenosis at coronary CTA, CMR, and RbPET show similar and moderate sensitivities but high specificities compared with ICA with FFR. This patient group represents a diagnostic challenge with frequent mismatch between advanced MPI tests and invasive measurements. (Danish Study of Non-Invasive Diagnostic Testing in Coronary Artery Disease 2 [Dan-NICAD 2]; NCT03481712)

The Utility of Coronary CT Angiography in Evaluating Symptomatic Patients with Positive MPI Referred for Coronary Angiography: A Single-center Experience

Background: Patients with suspected or known coronary artery disease (CAD) can be challenging to evaluate. Our study aims to assess the efficacy and utility of coronary computed tomographic angiography (CCTA) as a diagnostic method in patients with abnormal myocardial perfusion imaging (MPI) who were initially referred for Invasive Coronary Angiography (ICA). Methods: This is a single-center retrospective descriptive study. We evaluated 210 patients who underwent CCTA instead of ICA. Data of these patients were documented and analyzed accordingly. Results: Of the 210 patients who underwent CCTA, the procedure was found to be diagnostic in 172 (81.9%) patients. Of these 172 patients, 152 (88.4%) had normal coronaries or minor CAD, and 20 (11.6%) had significant disease requiring subsequent ICA. In 38 (18.1%) patients out of the total cohort, the CCTA was not diagnostic or could not be performed due to technical difficulties, requiring either ICA or another ischemia evaluation diagnostic modality. Conclusion: CCTA is a viable and reliable diagnostic tool for evaluating patients with suspected CAD referred for ICA following an abnormal MPI test. It is recommended as an initial test to rule out significant coronary stenosis and as it can avoid unnecessary ICA.

Utility of gated SPECT parameters in detection of coronary artery disease in patients with normal perfusion images

BackgroundFalse negative myocardial perfusion images on single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is a substantial problem in the interpretation of MPI. To explore possible parameters from gated SPECT that could detected coronary artery disease (CAD) in patients with normal perfusion images, we retrospectively selected patients who underwent a 2-day Tc-99 m MIBI adenosine stress/rest MPI and a subsequent invasive coronary angiography. Gated SPECT parameters, including end systolic volume (ESV), end diastolic volume (EDV), left ventricular ejection fraction (LVEF), and transient ischemic dilation (TID) ratio of patients with and without CAD were compared and assessed for their respective diagnostic performance using receiver operating characteristics (ROC) area under the curve (AUC).ResultsAmong 22 patients with normal perfusion images, 7 patients had CAD. Despite the small number of patients, we found significant differences between the ESV, the EDV, and the LVEF between patients with and without CAD. The analysis of ROC curve showed the stress ESV could excellently detect CAD (AUC = 0.900). The rest ESV, the stress EDV, the rest EDV, the stress LVEF and the rest LVEF could likewise perform well in the detection of CAD (AUC = 0.833, 0.819, 0.790, 0.862, and 0.838, respectively). In contrast, the change in LVEF and the TID ratio (AUC = 0.667 and 0.524, respectively) did not seem as reliable as other parameters. Optimal cutoffs for detection of CAD in patients with normal perfusion images from our study were ≥ 20.0 mL for the stress ESV, ≥ 71.0 mL for the stress EDV, ≤ 66.3 EF units for the stress LVEF, ≥ 18.0 mL for the rest ESV, ≥ 67.0 mL for the rest EDV and ≤ 70.0 EF unit for the rest LVEF.ConclusionsGated SPECT parameters could facilitate detection of CAD in patient with normal perfusion images on Tc-99m MIBI MPI. These parameters should be carefully interpreted to improve diagnostic accuracy and reduce false negative MPI.

Centralized Triage of Suspected Coronary Artery Disease Using Coronary Computed Tomographic Angiography to Optimize the Diagnostic Yield of Invasive Angiography

BackgroundCoronary computed tomographic angiography (CCTA) is preferable to invasive coronary angiography (ICA) for coronary artery disease (CAD) diagnosis in elective patients without known CAD. MethodsWe conducted a nonrandomized interventional study involving 2 tertiary care centres in Ontario. From July 2018 to February 2020, outpatients referred for elective ICA were identified through a centralized triage process and were recommended to undergo CCTA first instead of ICA. Patients with borderline or obstructive CAD on CCTA were recommended to undergo subsequent ICA. Intervention acceptability, fidelity, and effectiveness were assessed. ResultsA total of 226 patients were screened, with 186 confirmed to be eligible, of whom 166 had patient and physician approval to proceed with CCTA (89% acceptability). Among consenting patients, 156 (94%) underwent CCTA first; 43 (28%) had borderline/obstructive CAD on CCTA, and only 1 with normal/nonobstructive CAD on CCTA was referred for subsequent ICA against protocol (99% fidelity). Overall, 119 of 156 CCTA-first patients did not have ICA within the following 90 days (i.e., 76% potentially avoided ICA, due to the intervention). Among the 36 who underwent ICA post-CCTA per protocol, 24 had obstructive CAD (66.7% diagnostic yield). If all patients who were referred for and underwent ICA at either centre between July 2016 and February 2020 (n = 694 pre-implementation; n = 333 post-implementation) had had CCTA first, an additional 42 patients per 100 would have had an obstructive CAD finding on their ICA (95% confidence interval = 26-59). ConclusionA centralized triage process, in which elective outpatients referred for ICA are instead referred for CCTA first, appears to be acceptable and effective in diagnosing obstructive CAD and improving efficiencies in our healthcare system.

Coronary CT and timing of invasive coronary angiography in patients ≥75 years old with non-ST segment elevation acute coronary syndromes

BackgroundThe ability of coronary CT angiography (cCTA) to rule out significant coronary artery disease (CAD) in older patients with non-ST segment elevation acute coronary syndromes (NSTEACS) is unclear since valid...

Plaque composition on ultra-high-resolution coronary computed tomography angiography with optical coherence tomography correlation.

A 68-year-old man presented to our chest pain unit with angina and a low pre-test probability for coronary artery disease (CAD). Troponin levels were normal, and echocardiography showed an intact left ventricular function. Coronary computed tomography angiography (CCTA) was performed using a first-generation dual-source photon-counting detector computed tomography (PCD-CT, NAEOTOM Alpha®, Siemens Healthineers) in a novel ultra-high resolution (UHR) mode. Data were reconstructed at 0.6 and 0.2 mm to reflect the typical appearance on standard and PCD-CT scanners (Panels A/D and B/E, respectively). The RCX presented with a mixed plaque and moderate-to-severe stenosis, right coronary artery (RCA) with a soft plaque and moderate-to-severe stenosis (Panels A and B), and LAD with a mostly a calcified plaque and mild stenosis (Figure 1D). UHR reconstructions revealed a fibrous cap on the calcified plaque (Panel E). Subsequent invasive coronary angiography including optical coherence tomography (OCT) confirmed a significant stenosis in the RCA [Panel C, fibrous plaque with micro-calcifications (arrowhead)] and left circumflex coronary artery (LCX) (mostly fibrotic components). Both were successfully treated with drug-eluting stents [thrombolysis in myocardial infarction (TIMI) coronary grade flow 3 (TIMI 3)]. Further, OCT confirmed the mild stenosis of the LAD caused by lesion with a fibrous cap over the calcification (Panel F).

Comparison of second-line on-site computed quantitative flow ratio from coronary computed tomography angiography to PET perfusion imaging for detecting obstructive coronary artery disease

Abstract Introduction In patients with suspected obstructive coronary artery disease (CAD) on coronary computed tomography (CTA), guidelines endorse second-line selective testing for hemodynamic evaluation of suspected CAD. A variety of non-invasive modalities are available, and myocardial perfusion imaging with Rubidium-82 positron emission tomography (PET) is an established method with high diagnostic performance. Recently, an on-site method estimating computed tomography-derived quantitative flow ratio (CT-QFR) showed promising results for discriminating obstructive CAD. However, no study has compared the diagnostic performances of PET and CT-QFR. Purpose To assess a possible non-inferiority of CT-QFR compared to PET in patients with suspected obstructive CAD at CTA using invasive coronary angiography (ICA) with fractional flow reserve (FFR) as reference. Methods Patients (n=1732, 57% males, age 59±9.5) referred on a clinical indication with symptoms suggestive of obstructive CAD underwent routine CTA. Patients with ≥50% diameter stenosis (DS) on CTA were referred for PET and subsequent ICA with FFR. CT-QFR was analyzed post-hoc blinded to PET and ICA results. Abnormal CT-QFR was defined as CT-QFR ≤0.80 in any vessel with a diameter ≥1.5mm. An independent core-lab evaluated PET scans as abnormal/normal with optional analyst-dependent application of pre-specified criteria; summed stress score of ≥4 in ≥2 contiguous segments, vessel-specific myocardial blood flow (MBF) &amp;lt;2.00 ml/g/min, global myocardial blood flow reserve ≤1.8, and/or transient ischemic dilatation ratio &amp;gt;1.13. Obstructive CAD was defined as ICA with FFR ≤0.80 or high-grade stenosis (≥90% DS). Results In total, 445/1732 patients (25%) had suspected obstructive CAD on CTA of whom 400/445 patients (90%) underwent subsequent PET and ICA. CT-QFR was successfully analysed in 383/400 (96%) patients classifying 174/383 (45%) patients as having disease. In comparison, PET classified 130/383 (34%) patients as having disease. In total, obstructive CAD by ICA with FFR was identified in 162 (42%) patients. There was no significant difference in area under the receiver-operating characteristic curves for CT-QFR compared to the best performing PET metric (lowest vessel-specific MBF); 0.84 (95% CI 0.80–0.89) vs. 0.81 (0.77–0.85), p=0.19)) (Fig. 1). Overall diagnostic accuracy of CT-QFR versus PET was similar (78% (95% CI 74–82) vs. 77% (72–81), p=0.70. Sensitivities for CT-QFR and PET were 78% (71–84) and 63% (55–70), p&amp;lt;0.01, respectively, and specificities 78% (72–84) and 87% (82–91), p=0.01, respectively (Fig. 2). Three-vessel or left main disease on ICA was correctly identified in 30/31 patients by both CT-QFR and PET. Conclusion In patients with suspected obstructive CAD by CTA, second-line CT-QFR was non-inferior to PET for discriminating obstructive CAD by invasive FFR; Although diagnostic accuracy was similar, CT-QFR demonstrated higher sensitivity while PET showed higher specificity Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): Aarhus University PhD fellowshipRegion Mid Health Research Foundation

Diagnostic performance of on-site computation of quantitative flow ratio by a coronary computed tomography angiography based algorithm: comparison of distal and lesion-specific measurements

Abstract Introduction Guidelines recommend secondary ischemia assessment following a coronary computed tomography angiography (CTA) with suspected obstructive coronary artery disease (CAD). Coronary CTA-derived quantitative flow ratio (CT-QFR) is an on-site technique performed on acquired CTA images that estimates the functional severity of a coronary stenosis. However, CT-QFR measurements are available throughout the coronary vessel with no clear recommendations as to which specific values should be used for identifying obstructive CAD, e.g. most distal or lesion-specific values. Purpose First, to investigate the feasibility of CT-QFR and the correlation and agreement with invasive fractional flow reserve (FFR). Secondly, to compare the diagnostic performance of distal versus lesion-specific CT-QFR for identifying obstructive CAD defined by invasive coronary angiography (ICA) with FFR. Methods A total of 1732 prospectively included patients with symptoms suggestive of CAD referred for CTA were included. All patients with ≥50% diameter stenosis (DS) on CTA were subsequently referred for ICA with conditional FFR in lesions with 30–89%DS. Obstructive CAD was defined by ICA as FFR ≤0.80 or high-grade stenosis by visual assessment (≥90%DS). A blinded analysis of CT-QFR was performed in patients referred to ICA with measurements at the distal end of a vessel (distal CT-QFR) and 1 cm distal to stenotic lesions on CTA (lesion-specific). CT-QFR ≤0.80 was defined as abnormal. For correlation analyses to invasive FFR, CT-QFR was assessed corresponding to the position of the invasive pressure sensor. Results In total, 445/1732 (25%) patients had suspected obstructive CAD at CTA and underwent subsequent ICA. CT-QFR analysis was feasible in 423/445 (95%) patients. CT-QFR correlated (Pearson's rho 0.54, p&amp;lt;0.001) and agreed (mean difference –0.02±0.09) to FFR with CT-QFR overestimating FFR (Fig. 1). Obstructive CAD was identified in 190/423 (44%) patients by ICA. Distal and lesion-specific CT-QFR classified 196 (46%) and 171 (40%) patients as abnormal, respectively. Areas under the receiver-operating characteristic curves for distal versus lesion-specific CT-QFR were similar (0.86 (95% CI: 0.82–0.89) vs. 0.86 (0.82–0.90), p=0.80). Sensitivities for distal and lesion-specific CT-QFR were 78% (95% CI: 71–84) vs. 74% (67–80), p=0.01, respectively, and specificities 79% (95% CI: 74–84) vs. 87% (82–91), p&amp;lt;0.01, respectively. Distal and lesion-specific CT-QFR had similar diagnostic accuracy (79 (95% CI: 75–83), vs. 81 (77–85), p=0.07) (Fig. 2). Conclusion In patients with suspected obstructive CAD on CTA, non-invasive estimation of FFR using CT-QFR is feasible with moderate correlation and good agreement with invasive FFR. Overall diagnostic performance of distal and lesion-specific values for discriminating obstructive CAD by invasive FFR are similar. The use of CT-QFR could therefore potentially reduce the need for referral to invasive angiography after CTA. Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): Aarhus UniversityRegion Mid Jutland

Sex Differences in Computed Tomographic Angiography in Patients with Low and Intermediate Pretest Probability of Coronary Artery Disease

Background: Multi-slice computed tomography (MSCT) coronary angiography has become one of the hot spots in cardiovascular imaging technology. Many of the sex-based research have shown that women have different pathogenesis, clinical presentation and complication related to coronary artery disease (CAD) as compared to the males. The aim of this study investigated the relationship between gender and coronary artery calcium (CAC) in patients with chest discomfort with low and intermediate pretest probability of CAD who underwent Coronary computed tomography angiography (CCTA) and referrals by gender for subsequent invasive coronary angiography and revascularization.&#x0D; Methods: This prospective cohort study included 200 patients suspected to have coronary artery disease, negative or equivocal stress tests, with no prior known coronary artery disease (CAD), intermediate pretest probability for CAD according to the scoring method of (15-65 points), and Low likelihood for CAD (&lt; 15 points). Patients were divided into two groups according to gender and were followed up. All patients underwent Full history taking, full clinical examination, routine laboratory investigation, resting and exercise ECG, echocardiography, CT coronary angiography and invasive Coronary angiography.&#x0D; Results: Patients with mild calcium score level were significantly higher in no CAD group than CAD group (p &lt;0.001) and patients with high calcium score were significantly higher in CAD group than no CAD group (p &lt;0.001). In univariate regression analysis age, typical chest pain, obesity, coronary Ca score, and hyperlipidemia are independent predictors for CAD in females. In multivariate regression analysis, age, typical chest pain, hypertension, and coronary Ca score are predictors for CAD in males. Coronary calcium score is a good predicator for CAD (AUC =0.901, 95% CI =0.851-0.938, p value &lt;0.001). At cut off value &gt; 101, it has 70.97% sensitivity, 90.79% specificity, 92.6% PPV, and 65.7% NPV. Moreover, it is a good predicator for CAD in females (AUC =0.894, 95% CI =0.823 – 0.944, p value &lt;0.001). At cut off value &gt; 101, it has 60.71% sensitivity, 91.67% specificity, 87.2% PPV, and 71.4% NPV.&#x0D; Conclusions: In patients with chest discomfort with low and intermediate pretest probability of CAD who underwent CCTA and subsequent invasive coronary angiography and revascularization, female patients had lower age, hypertension, pretest probability score, calcium score, atypical angina, nonanginal chest pain and obstructive CAD but had higher BMI, typical angina than males’ group. In females, coronary calcium score is a good predicator for CAD. When its level exceeds 100, it has 60.71% sensitivity and 91.67% specificity. In addition, it was found that in females typical chest pain and coronary Ca score are predictors for CAD and in males, age, typical chest pain, hypertension, and coronary Ca score are predictors for CAD.

The Relationship Between Coronary Dominance and Positive Results in Myocardial Perfusion Imaging.

ObjectiveOur study aims to evaluate the possible relationship between coronary artery dominance and its effect on accurately identifying reversible ischemia of inferior/inferior-lateral wall on cardiac perfusion imaging.BackgroundCoronary artery dominance is conventionally defined by the vessel which gives the rise to the AV nodal artery/posterior descending artery (PDA). Previous studies have explored the potential effect of coronary dominance on the accuracy of single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) tests in detecting inferior/inferior-lateral wall ischemia; further evidence is necessary to study that potential effect.MethodsWe conducted a single-center retrospective analysis to explore the potential relationship between coronary artery dominance and inferior/inferior-lateral wall ischemia on SPECT imaging. We identified a cohort of patients with a reversible defect(s) in the inferior and/or inferolateral walls on SPECT MPI who had subsequently undergone invasive coronary angiography. Coronary angiography was used to determine coronary dominance and to confirm the presence/absence of obstructive coronary artery disease in the distribution of the inferior and/or inferolateral wall(s). We correlated the findings on SPECT MPI to coronary angiography to identify true positives and false positive MPIs.ResultsA cohort of 200 patients was identified, patients in the cohort had undergone stress MPI with reversible defects with subsequent invasive coronary angiography. Baseline characteristics including age, BMI and sex were fairly well-balanced between the groups. The mean age was 68 +/- 11 in the right dominant group and 70 +/- 9 in the non right dominant group. One hundred and sixty-one patients (81%) were found to have right dominant circulation and 39 patients (19%) were found to have left or codominant circulation. Of the 161 patients in the right dominant group, 58 patients (36%) were found to have false positive stress MPI. Of the 39 patients in the left or codominant group, 23 patients (59%) were found to have false positive stress MPI. The incidence of false positive stress MPI in the inferior and inferolateral distribution is significantly higher in patients with non-right dominant coronary anatomy (p-value: 0.01).ConclusionNon-right coronary dominant anatomy could have high false positive MPI results in the inferior and inferolateral distribution. Therefore, the interpreting clinicians should exercise caution during the clinical evaluation of these patients.