Pre-Coronary Artery Bypass Grafting Computed Tomography-Based Fractional Flow Reserve Predicts Graft Failure: Implications for Planning Invasive Treatment of Coronary Artery Disease.

OBJECTIVE: The aim of the study is to evaluate whether a pre-coronary artery bypass grafting (CABG) coronary computed tomography-based fractional flow reserve (FFR-CT) result at the site of a future anastomosis would predict the graft failure in patients undergoing CABG. METHODS: In 43 patients who had coronary computed tomography angiography (CCTA) prior to the CABG, follow-up CCTA were acquired >12 months post-CABG procedure. The FFR-CT values were simulated on the basis of the pre-CABG CCTA. Based on follow-up CCTA, the anastomosis sites and the graft patency were determined. The graft failure was defined as either its stenosis >50% or occlusion. RESULTS: Ninety eight (44 saphenous, 54 left or right internal mammary artery) grafts were assessed. Eighteen grafts from 16 patients were dysfunctional on follow-up CCTA. The FFR-CT values at the location of future anastomosis were higher in dysfunctional than in normal grafts (0.77 [0.71-0.81] vs 0.60 [0.56-0.66], respectively, P = 0.0007). Pre-CABG FFR-CT (hazard ratio = 1.1; 95% CI: 1.012-1.1, P = 0.0230), and bypass graft to right coronary artery (hazard ratio = 3.7; 95% CI: 1.4-9.3 vs left anterior descending artery) were independent predictors of graft dysfunction during follow-up. The optimal threshold of FFR-CT to predict graft failure was >0.68 (sensitivity 88.9% (95% CI: 65.3-98.6), specificity 63.7% (95% CI: 52.2-74.2), positive predictive value 35.6% (95% CI: 28.3%-43.5%), negative predictive value 96.2% (95% CI: 87.2%-99.0%)). CONCLUSIONS: Pre-CABG functional FFR-CT predicts future coronary bypass graft failure. This shows utility of FFR-CT for guiding coronary revascularization and also suggests significance of physiological assessment prior to CABG.

Diet and Lifestyle Intervention-Induced Pattern of Weight Loss Related to Reduction in Low-Attenuation Coronary Plaque Burden.

BACKGROUND: Despite extensive research on body weight and cardiovascular risk, the mechanistic relationship between weight loss and coronary plaque modification has not been adequately addressed. This study aimed to determine the association between body composition dynamics and low-attenuation coronary plaque (LAP) burden. METHODS: Eighty-nine participants (40% women, 60 ± 7.7 years) of the Dietary Intervention to Stop Coronary Atherosclerosis in Computed Tomography (DISCO-CT) study with non-obstructive atherosclerosis with nonobstructive atherosclerosis confirmed in computed tomography angiography (CCTA), a randomized (1:1), prospective, single-center study were included into the analysis. Patients were randomly assigned to either experimental arm (intensive diet and lifestyle intervention atop optimal medical therapy, n = 45) or control arm (optimal medical therapy alone, n = 44) over 66.8 ± 13.7 weeks. Changes (∆) in body mass (BM) and body composition parameters, including total body fat (TBF), skeletal muscle mass (SMM), and fat-to-muscle ratio (FMR), measured with bioimpedance analyzer were compared with CCTA-measured ∆LAP. Coronary plaque analysis was performed using the 2 × 192 dual-energy scanner (Somatom Force, Siemens, Germany), while quantitative coronary plaque measurements were performed using a semi-automated plaque analysis software system (QAngioCT v3.1.3.13, Medis Medical Imaging Systems, Leiden, The Netherlands). RESULTS: Significant intergroup differences were found for ∆BM (-3.6 ± 4.9 kg in the experimental vs. -1.4 ± 2.9 kg in the control group, p = 0.015), ∆TBF (-3.4 ± 4.8% in the experimental vs. 1.1 ± 5.5% in the control arm, p < 0.001), ∆SMM (1.9 ± 2.8% in the experimental vs. -0.7 ± 3.2% in the control arm, p < 0.001), and FMR [-12.9 (-21.2; -4.3)% in the experimental vs. 3.1 (-5.3; 10.7)% in the control arm, p < 0.001]. ∆LAP did not differ significantly between the study arms; however, in the whole study population, ∆LAP was positively correlated with ∆BM, ∆TBF, and ∆FMR (r = 0.45, p < 0.001; r = 0.300, p = 0.004; r = 0.233, p = 0.028, respectively), and negatively with ∆SMM (r = -0.285, p = 0.007). Multivariate linear regression analysis revealed the association of ∆LAP with ∆BM, ∆TBF, and ∆FMR. CONCLUSIONS: The study intervention resulted in BM reduction characterized by fat loss, skeletal muscle gain, and increased FMR. This weight loss pattern may lead to a reduction in high-risk coronary plaque. Compared to a simple weight control, tracking body composition changes over time can provide valuable information on adverse coronary plaque modification.

Coronary Artery Calcium Score Predicts Major Adverse Cardiovascular Events in Stable Chest Pain.

Background Coronary artery calcium (CAC) has prognostic value for major adverse cardiovascular events (MACE) in asymptomatic individuals, whereas its role in symptomatic patients is less clear. Purpose To assess the prognostic value of CAC scoring for MACE in participants with stable chest pain initially referred for invasive coronary angiography (ICA). Materials and Methods This prespecified subgroup analysis from the Diagnostic Imaging Strategies for Patients With Stable Chest Pain and Intermediate Risk of Coronary Artery Disease (DISCHARGE) trial, conducted between October 2015 and April 2019 across 26 centers in 16 countries, focused on adult patients with stable chest pain referred for ICA. Participants were randomly assigned to undergo either ICA or coronary CT. CAC scores from noncontrast CT scans were categorized into low, intermediate, and high groups based on scores of 0, 1-399, and 400 or higher, respectively. The end point of the study was the occurrence of MACE (myocardial infarction, stroke, and cardiovascular death) over a median 3.5-year follow-up, analyzed using Cox proportional hazard regression tests. Results The study involved 1749 participants (mean age, 60 years ± 10 [SD]; 992 female). The prevalence of obstructive coronary artery disease (CAD) at CT angiography rose from 4.1% (95% CI: 2.8, 5.8) in the CAC score 0 group to 76.1% (95% CI: 70.3, 81.2) in the CAC score 400 or higher group. Revascularization rates increased from 1.7% to 46.2% across the same groups (P < .001). The CAC score 0 group had a lower MACE risk (0.5%; HR, 0.08 [95% CI: 0.02, 0.30]; P < .001), as did the 1-399 CAC score group (1.9%; HR, 0.27 [95% CI: 0.13, 0.59]; P = .001), compared with the 400 or higher CAC score group (6.8%). No significant difference in MACE between sexes was observed (P = .68). Conclusion In participants with stable chest pain initially referred for ICA, a CAC score of 0 showed very low risk of MACE, and higher CAC scores showed increasing risk of obstructive CAD, revascularization, and MACE at follow-up. Clinical trial registration no. NCT02400229 © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Hanneman and Gulsin in this issue.

Age and Computed Tomography and Invasive Coronary Angiography in Stable Chest Pain: A Prespecified Secondary Analysis of the DISCHARGE Randomized Clinical Trial.

Importance: The effectiveness and safety of computed tomography (CT) and invasive coronary angiography (ICA) in different age groups is unknown. Objective: To determine the association of age with outcomes of CT and ICA in patients with stable chest pain. Design, Setting, and Participants: The assessor-blinded Diagnostic Imaging Strategies for Patients With Stable Chest Pain and Intermediate Risk of Coronary Artery Disease (DISCHARGE) randomized clinical trial was conducted between October 2015 and April 2019 in 26 European centers. Patients referred for ICA with stable chest pain and an intermediate probability of obstructive coronary artery disease were analyzed in an intention-to-treat analysis. Data were analyzed from July 2022 to January 2023. Interventions: Patients were randomly assigned to a CT-first strategy or a direct-to-ICA strategy. Main Outcomes and Measures: MACE (ie, cardiovascular death, nonfatal myocardial infarction, or stroke) and major procedure-related complications. The primary prespecified outcome of this secondary analysis of age was major adverse cardiovascular events (MACE) at a median follow-up of 3.5 years. Results: Among 3561 patients (mean [SD] age, 60.1 [10.1] years; 2002 female [56.2%]), 2360 (66.3%) were younger than 65 years, 982 (27.6%) were between ages 65 to 75 years, and 219 (6.1%) were older than 75 years. The primary outcome was MACE at a median (IQR) follow-up of 3.5 (2.9-4.2) years for 3523 patients (99%). Modeling age as a continuous variable, age, and randomization group were not associated with MACE (hazard ratio, 1.02; 95% CI, 0.98-1.07; P for interaction = .31). Age and randomization group were associated with major procedure-related complications (odds ratio, 1.15; 95% CI, 1.05-1.27; P for interaction = .005), which were lower in younger patients. Conclusions and Relevance: Age did not modify the effect of randomization group on the primary outcome of MACE but did modify the effect on major procedure-related complications. Results suggest that CT was associated with a lower risk of major procedure-related complications in younger patients. Trial Registration: ClinicalTrials.gov Identifier: NCT02400229.

Effect of Body Mass Index on Effectiveness of CT versus Invasive Coronary Angiography in Stable Chest Pain: The DISCHARGE Trial.

Background Recent trials support the role of cardiac CT in the evaluation of symptomatic patients suspected of having coronary artery disease (CAD); however, body mass index (BMI) has been reported to negatively impact CT image quality. Purpose To compare initial use of CT versus invasive coronary angiography (ICA) on clinical outcomes in patients with stable chest pain stratified by BMI category. Materials and Methods This prospective study represents a prespecified BMI subgroup analysis of the multicenter Diagnostic Imaging Strategies for Patients with Stable Chest Pain and Intermediate Risk of Coronary Artery Disease (DISCHARGE) trial conducted between October 2015 and April 2019. Adult patients with stable chest pain and a CAD pretest probability of 10%-60% were randomly assigned to undergo initial CT or ICA. The primary end point was major adverse cardiovascular events (MACE), including cardiovascular death, nonfatal myocardial infarction, or stroke. The secondary end point was an expanded MACE composite, including transient ischemic attack, and major procedure-related complications. Competing risk analyses were performed using the Fine and Gray subdistribution Cox proportional hazard model to assess the impact of the relationship between BMI and initial management with CT or ICA on the study outcomes, whereas noncardiovascular death and unknown causes of death were considered competing risk events. Results Among the 3457 participants included, 831 (24.0%), 1358 (39.3%), and 1268 (36.7%) had a BMI of less than 25, between 25 and 30, and greater than 30 kg/m2, respectively. No interaction was found between CT or ICA and BMI for MACE (P = .29), the expanded MACE composite (P = .38), or major procedure-related complications (P = .49). Across all BMI subgroups, expanded MACE composite events (CT, 10 of 409 [2.4%] to 23 of 697 [3.3%]; ICA, 26 of 661 [3.9%] to 21 of 422 [5.1%]) and major procedure-related complications during initial management (CT, one of 638 [0.2%] to five of 697 [0.7%]; ICA, nine of 630 [1.4%] to 12 of 422 [2.9%]) were less frequent in the CT versus ICA group. Participants with a BMI exceeding 30 kg/m² exhibited a higher nondiagnostic CT rate (7.1%, P = .044) compared to participants with lower BMI. Conclusion There was no evidence of a difference in outcomes between CT and ICA across the three BMI subgroups. Clinical trial registration no. NCT02400229 © RSNA, 2024 Supplemental material is available for this article.

Computed tomographic characteristics of congenital coronary artery fistulas in an adult population.

BACKGROUND: Coronary artery fistulas (CAFs) are usually congenital coronary artery anomalies of termination. AIMS: This study aimed to assess the prevalence, anatomic characteristics, and clinical significance of CAFs detected by computed tomography (CT) in an adult population. METHODS: We performed 45 817 CT examinations in 39 066 subjects between 2008 and 2020. The electronic database was manually checked using specific keywords to identify patients with CAFs. The CT characteristics of CAFs were evaluated. CAF was defined as clinically significant if it was the most plausible cause of myocardial infarction, infective endocarditis, heart failure, death during follow-up, hospitalization, or if it required either percutaneous or surgical intervention. RESULTS: Of 39 066 patients, 56 CAFs were detected in 42 subjects (20 men, 47.6%) with a prevalence of 0.11%. Most CAFs originated from the right coronary artery (RCA) (48.2%) and drained into the pulmonary artery (PA) (58.9%). CAFs terminating in the PA were more frequently multiple (P <0.001) and tortuous (P <0.001) as compared to CAFs without PA drainage. Clinically significant CAFs, identified in 7 of 42 patients, were more common in younger (P = 0.03) and male (P = 0.04) subjects and had larger lumen area and diameter at the site of origin (P = 0.03, P = 0.03, respectively). CONCLUSIONS: In the unselected adult population undergoing coronary CT angiography, the RCA and the PA are the most common sites of origin and termination of CAFs, respectively. CAFs draining into the PA are more often multiple and tortuous. Clinically meaningful CAFs are larger and most frequently detected in younger and male patients.

Impact of smoking in patients with suspected coronary artery disease in the randomised DISCHARGE trial.

OBJECTIVES: To investigate if the effect of cardiac computed tomography (CT) vs. invasive coronary angiography (ICA) on cardiovascular events differs based on smoking status. MATERIALS AND METHODS: This pre-specified subgroup analysis of the pragmatic, prospective, multicentre, randomised DISCHARGE trial (NCT02400229) involved 3561 patients with suspected coronary artery disease (CAD). The primary endpoint was major adverse cardiovascular events (MACE: cardiovascular death, non-fatal myocardial infarction, or stroke). Secondary endpoints included an expanded MACE composite (MACE, transient ischaemic attack, or major procedure-related complications). RESULTS: Of 3445 randomised patients with smoking data (mean age 59.1 years + / - 9.7, 1151 men), at 3.5-year follow-up, the effect of CT vs. ICA on MACE was consistent across smoking groups (p for interaction = 0.98). The percutaneous coronary intervention rate was significantly lower with a CT-first strategy in smokers and former smokers (p = 0.01 for both). A CT-first strategy reduced the hazard of major procedure-related complications (HR: 0.21, 95% CI: 0.03, 0.81; p = 0.045) across smoking groups. In current smokers, the expanded MACE composite was lower in the CT- compared to the ICA-first strategy (2.3% (8) vs 6.0% (18), HR: 0.38; 95% CI: 0.17, 0.88). The rate of non-obstructive CAD was significantly higher in all three smoking groups in the CT-first strategy. CONCLUSION: For patients with stable chest pain referred for ICA, the clinical outcomes of CT were consistent across smoking status. The CT-first approach led to a higher detection rate of non-obstructive CAD and fewer major procedure-related complications in smokers. CLINICAL RELEVANCE STATEMENT: This pre-specified sub-analysis of the DISCHARGE trial confirms that a CT-first strategy in patients with stable chest pain referred for invasive coronary angiography with an intermediate pre-test probability of coronary artery disease is as effective as and safer than invasive coronary angiography, irrespective of smoking status. TRIAL REGISTRATION: ClinicalTrials.gov NCT02400229. KEY POINTS: • No randomised studies have assessed smoking status on CT effectiveness in symptomatic patients referred for invasive coronary angiography. • A CT-first strategy results in comparable adverse events, fewer complications, and increased coronary artery disease detection, irrespective of smoking status. • A CT-first strategy is safe and effective for stable chest pain patients with intermediate pre-test probability for CAD, including never smokers.

Computed Tomography Versus Invasive Coronary Angiography in Patients With Diabetes and Suspected Coronary Artery Disease.

OBJECTIVE: To compare cardiac computed tomography (CT) with invasive coronary angiography (ICA) as the initial strategy in patients with diabetes and stable chest pain. RESEARCH DESIGN AND METHODS: This prespecified analysis of the multicenter DISCHARGE trial in 16 European countries was performed in patients with stable chest pain and intermediate pretest probability of coronary artery disease. The primary end point was a major adverse cardiac event (MACE) (cardiovascular death, nonfatal myocardial infarction, or stroke), and the secondary end point was expanded MACE (including transient ischemic attacks and major procedure-related complications). RESULTS: Follow-up at a median of 3.5 years was available in 3,541 patients of whom 557 (CT group n = 263 vs. ICA group n = 294) had diabetes and 2,984 (CT group n = 1,536 vs. ICA group n = 1,448) did not. No statistically significant diabetes interaction was found for MACE (P = 0.45), expanded MACE (P = 0.35), or major procedure-related complications (P = 0.49). In both patients with and without diabetes, the rate of MACE did not differ between CT and ICA groups. In patients with diabetes, the expanded MACE end point occurred less frequently in the CT group than in the ICA group (3.8% [10 of 263] vs. 8.2% [24 of 294], hazard ratio [HR] 0.45 [95% CI 0.22-0.95]), as did the major procedure-related complication rate (0.4% [1 of 263] vs. 2.7% [8 of 294], HR 0.30 [95% CI 0.13 - 0.63]). CONCLUSIONS: In patients with diabetes referred for ICA for the investigation of stable chest pain, a CT-first strategy compared with an ICA-first strategy showed no difference in MACE and may potentially be associated with a lower rate of expanded MACE and major procedure-related complications.

Identification of noncalcified coronary plaque characteristics using machine learning radiomic analysis of non-contrast high-resolution computed tomography.

BACKGROUND: Novel imaging and analysis techniques may offer the ability to detect noncalcified or high-risk coronary plaques on a non-contrast computer tomography (CT) scan, advancing cardiovascular diagnostics. AIMS: We aimed to explore whether machine learning (ML) radiomic analysis of low-dose high-resolution non-contrast electrocardiographically (ECG) gated cardiac CT scan allows for the identification of noncalcified coronary plaque characteristics. METHODS: We prospectively enrolled 125 patients with noncalcified plaques and adverse plaque characteristics (APC) and 25 controls without visible atherosclerosis on coronary CT angiography (CCTA). All patients underwent non-contrast CT exam before CCTA. Four hundred and nineteen radiomic features were calculated to identify the presence of any coronary artery disease (CAD), obstructive CAD (stenosis >50%), plaque with ≥2 APC, degree of calcification, and specific APCs. ML models were trained on a training set (917 segmentations) and tested (validation) on a separate set (292 segmentations). RESULTS: Among the radiomic features, 88.3% were associated with a plaque, 0.9% with obstructive CAD, and 76.4% with the presence of at least two APCs. Overall, 80.2%, 88.5%, and 36.5%, of features were associated with calcified, partially calcified, and noncalcified plaques, respectively. Regarding APCs, 61.1%, 61.8%, 84.2%, and 61.3% of features were associated with low attenuation (LAP), napkin-ring sign (NRS), spotty calcification (SC), and positive remodeling (PR), respectively. ML models outperformed conventional methods for the presence of plaque obstructive stenosis, and the presence of 2 APCs, as well as for noncalcified plaques and partially calcified plaques, but not for calcified plaques. ML models also significantly outperformed identification of LAP and PR, but neither NRS nor SC. CONCLUSION: Radiomic analysis of non-contrast cardiac CT exams may allow for the identification of specific noncalcified coronary plaque characteristics displaying the potential for future clinical applications.

Computed tomography perfusion and angiography in patients with chronic total occlusion undergoing percutaneous coronary intervention.

BACKGROUND AND AIMS: Myocardial perfusion imaging (MPI) and anatomical imaging with coronary computed tomography angiography (CCTA) can play an important role in the preprocedural planning of a chronic total occlusion (CTO) percutaneous coronary intervention (PCI). We aimed to establish the feasibility of a novel dynamic computed tomography perfusion (CTP) analysis for the assessment of myocardial perfusion before and after a successful recanalization of CTO in patients undergoing CCTA as part of a standard preprocedural workup. METHODS: In a prospective observational study symptomatic patients underwent dynamic CTP on a dual-source CT scanner both before and 3 months after successful CTO PCI. RESULTS: Twenty-seven patients completed the study (63 ± 8 years old, 78% male). Following successful CTO PCI, there was a significant reduction in the ischemic burden (5 [5-7] versus 1 [0-2] segments, p < 0.001), and improvement in myocardial blood flow (85.3 [71.7-94.1] versus 134.6 [123.8-156.9] mL/min, p < 0.001) resulting in an increase in the relative flow reserve (0.49 [0.41-0.57] versus 0.88 [0.74-0.95], p < 0.001). CONCLUSIONS: CTP emerges as a robust and safe method for MPI in CTO patients. The single imaging session assessment of both coronary anatomy and perfusion with CT lends itself to precise disease phenotyping in the challenging population of CTO patients.

Pericoronary adipose tissue density is increased in patients with recent spontaneous coronary dissection.

OBJECTIVE: Inflammatory activity is one of the potential mechanisms of spontaneous coronary artery dissection (SCAD). Recently, the pericoronary adipose tissue attenuation (PCAT) derived from CT angiography (CTA) has been established as a method for measuring vascular inflammation. We aimed to characterise the pancoronary and vessel-specific PCAT in patients with and without recent SCAD. METHODS: The study comprised patients with SCAD referred to a tertiary centre between 2017 and 2022 who underwent CTA and were compared with individuals with no prior SCAD. PCAT was analysed on end-diastolic CTA reconstructions along proximal 40 mm of all major coronary vessels as well as the SCAD-related vessel. We analysed 48 patients with recent SCAD (median 6.1 (IQR 3.5-14.9) months since SCAD, 95.8% female) and 48 patients in the group without SCAD. RESULTS: Pancoronary PCAT was higher in patients with SCAD compared with those without SCAD (-80.6±7.9 vs -85.3 HU±6.1, p=0.002). Vessel-specific PCAT in patients with SCAD compared with patients without SCAD was higher for both the RCA (-80.9±9.5 vs -87.1±6.9 HU, p=0.001) and the LCA (-80.3±7.8 vs -83.4±7.2 HU, p=0.04). In patients with SCAD, PCAT of the SCAD-related vessel was not significantly different from averaged PCAT of unaffected vessels (-81.2±9.2 vs -80.6±7.6, p=0.74). There was no association between PCAT and the interval from SCAD to CTA. CONCLUSIONS: Patients with recent SCAD have higher PCAT compared with patients without SCAD, suggesting an increased perivascular inflammatory activity. This association is not restricted to the dissected vessel.

Assessment of consistency in aortic valve sizing between surgical and transcatheter aortic valve replacement.

Introduction: One of the crucial aspects of transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR) is the valve prosthesis selection. Aim: To assess the consistency of the aortic valve sizing in SAVR and TAVR by comparing the sizes of aortic prostheses selected based on the intraprocedural annulus measurements and simulation of the TAVR planning. Material and methods: The study comprised of 167 patients with aortic stenosis treated with SAVR. Simulation of the prosthesis sizing blinded to the SAVR results was performed based on the assessment of cardiac computed tomography (CCT) images. Results: Based on the CCT images, the average value of the aortic annulus diameter was 25.4 ±3.0 mm. Aortic valve calcifications were mild in 29 cases, moderate in 78 cases, and severe in 53 cases. The sizes of the valves recommended by the simulations were larger than valves surgically implanted in 98.6% of patients for self-expanding and in 91.7% of patients for balloon-expandable prostheses. The average difference for self-expanding prostheses was 6.4 mm and 4.5 mm for balloon expandable valves. Additionally, a negative correlation was observed for the difference in prosthesis size and size of the valve used by surgeons. Conclusions: There is a systematic difference between sizes of aortic prostheses used in SAVR and TAVR. Further studies are needed to evaluate if the difference in prosthesis size selection contributes to the frequency of prosthesis-patient mismatch phenomenon and burden of high postoperative mean transaortic gradient.

Atherosclerosis Imaging Quantitative Computed Tomography (AI-QCT) to guide referral to invasive coronary angiography in the randomized controlled CONSERVE trial.

AIMS: We compared diagnostic performance, costs, and association with major adverse cardiovascular events (MACE) of clinical coronary computed tomography angiography (CCTA) interpretation versus semiautomated approach that use artificial intelligence and machine learning for atherosclerosis imaging-quantitative computed tomography (AI-QCT) for patients being referred for nonemergent invasive coronary angiography (ICA). METHODS: CCTA data from individuals enrolled into the randomized controlled Computed Tomographic Angiography for Selective Cardiac Catheterization trial for an American College of Cardiology (ACC)/American Heart Association (AHA) guideline indication for ICA were analyzed. Site interpretation of CCTAs were compared to those analyzed by a cloud-based software (Cleerly, Inc.) that performs AI-QCT for stenosis determination, coronary vascular measurements and quantification and characterization of atherosclerotic plaque. CCTA interpretation and AI-QCT guided findings were related to MACE at 1-year follow-up. RESULTS: Seven hundred forty-seven stable patients (60 ± 12.2 years, 49% women) were included. Using AI-QCT, 9% of patients had no CAD compared with 34% for clinical CCTA interpretation. Application of AI-QCT to identify obstructive coronary stenosis at the ≥50% and ≥70% threshold would have reduced ICA by 87% and 95%, respectively. Clinical outcomes for patients without AI-QCT-identified obstructive stenosis was excellent; for 78% of patients with maximum stenosis < 50%, no cardiovascular death or acute myocardial infarction occurred. When applying an AI-QCT referral management approach to avoid ICA in patients with <50% or <70% stenosis, overall costs were reduced by 26% and 34%, respectively. CONCLUSIONS: In stable patients referred for ACC/AHA guideline-indicated nonemergent ICA, application of artificial intelligence and machine learning for AI-QCT can significantly reduce ICA rates and costs with no change in 1-year MACE.

Benefits of the selective invasive strategy guided by CTA and CTA-derived fractional flow reserve in patients with coronary artery disease.

BACKGROUND: Coronary computed tomography angiography (CTA) has high diagnostic accuracy in ruling out significant stenosis of coronary arteries. The additional use of CTA- derived fractional flow reserve (FFR) further enhances diagnostic utility of coronary CTA. Some patients interrogated non-invasively have diseased coronary arteries and undergo further diagnostic testing, including invasive coronary angiography (ICA). Patients with one-vessel disease may benefit from invasive interrogation limited to the diseased vessel only. AIMS: We analyzed the impact of a "diseased-vessel-only" selective invasive diagnostic approach in 100 patients undergoing ICA following coronary CTA (and CT-FFR) as compared to the traditional "full ICA" approach. We aimed to compare contrast volume and radiation dose used during ICA in both scenarios, seeking potential benefits for the patient in reducing those values by the "dis-eased-vessel-only" approach. RESULTS: Sensitivity, specificity, positive predictive value, and negative predictive value of CTA in prediction of subsequent revascularization were 96%, 75%, 51%, and 99%, respectively, and for CT-FFR 90%, 90%, 69%, and 97%, respectively. Using CTA as a method to guide ICA would reduce contrast volume and estimated radiation dose (ED) by 35% and 42.0%, respectively (P <0.0001 for both). Taking into consideration CT-FFR results, contrast volume would be reduced by 57% and ED by 69% (P <0.0001 for both). CONCLUSION: These real-world data support the concept that vessels with <50% diameter stenosis on quantitative computed tomography and with hemodynamically insignificant CTA-derived FFR result may be omitted during ICA. Such an approach would result in substantial reductions in con-trast media volume used, as well as patients' exposure to radiation during ICA, while not leading to misdiagnoses.

High-density lipoprotein cholesterol, triglycerides, and characteristics of coronary atherosclerosis in patients with significant coronary artery disease newly diagnosed by computed tomography coronary angiography.

BACKGROUND: The Current European Society of Cardiology guidelines indicate specific target low-density lipoprotein cholesterol (LDL-C) levels for different cardiovascular risk categories in terms of prevention. However, the target for high-density lipoprotein cholesterol (HDL-C) and triglycerides has not been established. AIM: The study aims to investigate the associations betweenHDL-C,triglycerides, andcoronary plaque characteristics. METHODS: This was a prospective single-center study with enrolled consecutive patients with newly diagnosed significant (≥1stenosis ≥50%) CAD on computed tomography coronary angiography (CTCA). Patients had lipids andCTCA analysis, including high-risk plaque (HRP) features: low-attenuation plaque (LAP), napkin-ring sign (NRS), positive remodeling (PR), and spotty calcium (SC), type of the plaque (calcified, noncalcified, mixed), and their composition (calcified, fibrous, fibro-fatty, necrotic core). RESULTS: The study included 300 patients (191 men, 66 [8] years). Sixty-six percent of them had lipid-lowering therapy. HRPwas found in 208 patients. There was no association between LDL-C, plaque composition, and HRP presence. There was a negative correlation between HDL-C, fibro-fatty and necrotic core plaque components (P = 0.0002, P = 0.0009). There was a positive correlation between triglycerides and necrotic core (P = 0.038). There were differences in HDL-C and triglycerides in patients with and without NRS (47 vs. 53 mg/dl, P = 0.0002 and 128 vs. 109 mg/dl, P = 0.02). In logistic regression, HDL-C (odds ratio [OR], 0.95;95% confidence interval [CI], 0.93-0.98; P <0.001), triglycerides (OR, 1.00; 95% CI, 1.00-1.01; P = 0.02), and male sex (OR, 3.04; 95% CI, 1.41-6.52; P = 0.004) were NRS predictors. In multivariable regression, only HDL-C (OR, 0.96; 95% CI, 0.93-0.99; P = 0.02) was an independent predictor of NRS. CONCLUSION: Lower HDL-C and higher triglycerides were associated with NRS presence and more necrotic core plaque components in coronary plaques in patients with newly diagnosed CAD.