Recovery of cardiovascular diagnostic testing in Italy 1 year after coronavirus disease-2019 outbreak compared with other countries in Europe and worldwide: results from the International Atomic Energy Agency INCAPS COVID 2 survey.

Aims: Recovery of cardiovascular diagnostic testing in Italy after the coronavirus disease-2019 (COVID-19) pandemic has not been quantified. The study aims to describe cardiac diagnostic procedure volumes, centres practice and protocols, and staff members' well-being 1 year after COVID-19 outbreak in Italy. Methods and results: A global survey was conducted by the International Atomic Energy Agency to evaluate changes in cardiac diagnostic procedure volumes in April 2021. Evaluated procedures were transoesophageal echocardiogram, coronary computed tomography angiography, coronary artery calcium scanning, nuclear medicine infection studies, invasive coronary angiography, rest and stress transthoracic echocardiogram, cardiac magnetic resonance, single-photon emission computed tomography and positron emission tomography, and stress electrocardiogram. Data were compared with April 2020 and March 2019. Forty-two Italian centres took part in the survey. In April 2020, there was a 72% decrease of median volumes of cardiac diagnostic procedures compared with March 2019. In April 2021, volumes of cardiac diagnostic procedures remained decreased by 3% when compared with March 2019. Stress electrocardiogram, coronary computed tomography angiography, and stress cardiac magnetic resonance volumes increased in April 2021 compared with baseline (29%, 6%, and 16%, respectively). The majority of centres had adopted physical distancing measures (93%), COVID-19 screening through questionnaires (76%), or temperature checks (93%). Twenty-five per cent of physicians at Italian responding sites reported excessive levels of psychological stress. Conclusion: In April 2021, volumes of cardiac diagnostic procedures at Italian responding sites were still recovering. Centres had implemented several adaptations to ensure the provision of care to their patients. Even 1 year after the pandemic, a substantial minority of Italian healthcare providers were still experiencing excessive psychological stress.

The coronavirus disease-2019 pandemic has had an impact on cardiovascular care provision, leading to a decrease in the number of diagnostic procedures performed. As of April 2021, volumes of cardiovascular diagnostic procedures in Italy were still recovering, despite the implementation of several adaptations by healthcare centres to deal with the pandemic.

Impact of an institutional process change adopting end-systolic coronary CTA acquisition and automated dose selection on patient throughput and image quality.

INTRODUCTION: Guidelines recommend prospective ECG-triggered mid-diastolic coronary computed tomographic angiography (CCTA) acquisition after achieving optimal heart rate (HR) control in order to optimize scan image quality. With dual-source CCTA, prospective end-systolic acquisition has been shown to be less prone to motion artifacts at higher heart rates and may improve scan and CT laboratory efficiency by allowing CCTA without routine pre-scan beta-blocker (BB) administration. METHODS: We implemented an institutional process change in CCTA performance effective January 2023, comprising a transition from prospective ECG-triggered mid-diastolic acquisitions individually supervised by a physician at the scanner to an algorithmic approach predominately utilizing prospective end-systolic acquisition (200-400 â€‹ms after R peak), employing an automated dose selection algorithm, without BB administration. All scans were performed on a third-generation 192-slice dual-source scanner. We reviewed 300 consecutive CCTAs done pre- and post-process change in Jan 2022 (phase 0), Jan 2023 (phase 1), and in May 2023 (phase 2) after implementation of a process improvement involving more selective utilization of automated tube potential/current algorithms (CARE kV) to optimize image quality. Coronary segmental image quality was assessed by two experienced CCTA readers by consensus using an 18-segment SCCT model on a 5-point Likert scale (1 â€‹= â€‹non-interpretable; 2 â€‹= â€‹poor; 3 â€‹= â€‹acceptable; 4 â€‹= â€‹good; 5 â€‹= â€‹excellent). Measures of radiation dose, medication administration, and time required for patient scanning were compared. Logistic regression was used to determine factors associated with patient-level reduction in image quality (IQ) and with repeat scans. RESULTS: Post-process change, there was a significant reduction in the median overall patient appointment [phase 0: 95 (75-125) min vs. phase 1: 68 (52-88) min and phase 2: 72 (59-90) min; P â€‹< â€‹0.001] and scan times [phase 0: 13 (10-16) min vs. phase 1: 8 (6-13) min and phase 2: 9 (7-13) min; P â€‹< â€‹0.001]. Median IQ score in both post-process change phases was 4 (4-5) compared to a median score of 5 (4-5) pre-process change (P for comparison <0.001). The majority of segments post-process change had "good" IQ (Phase 1 segmental IQ scores: 5 â€‹= â€‹36.7 â€‹%, 4 â€‹= â€‹46.8 â€‹%, 3 â€‹= â€‹13 â€‹%, 2 â€‹= â€‹2.6 â€‹%, 1 â€‹= â€‹0.9 â€‹%; Phase 2 segmental IQ scores: 5 â€‹= â€‹26 â€‹%, 4 â€‹= â€‹49.7 â€‹%, 3 â€‹= â€‹16.3 â€‹%, 2 â€‹= â€‹6.1 â€‹%, 1 â€‹= â€‹1.9 â€‹%), whereas pre-process change, the majority of segments had "excellent" IQ (Phase 0 segmental IQ scores: 5 â€‹= â€‹56 â€‹%, 4 â€‹= â€‹34.3 â€‹%, 3 â€‹= â€‹7.5 â€‹%, 2 â€‹= â€‹1.8 â€‹%, 1 â€‹= â€‹0.4 â€‹%) There was no significant increase in non-interpretable scans at the patient level. The 22 â€‹% re-scan rate in phase 1 (vs. 6 â€‹% in phase 0, P â€‹= â€‹.002) improved to 15 â€‹% in phase 2. While patient related factors of body mass index [adjusted OR obese 2.64, 95 â€‹% CI 1.12-6.51, P â€‹= â€‹0.03; aOR morbidly obese 6.94, 95 â€‹% CI 2.21-23.52, P â€‹= â€‹0.001] and average HR [aOR (per 10 bpm increase) 1.51, 95 â€‹% CI 1.21-1.9, P â€‹< â€‹0.001] were associated with the scoring of any segment as â€‹≤ â€‹3 â€‹at the patient level in a fully adjusted model, the improved phase 2 of the process change was not [aOR 1.61, 95 â€‹% CI 0.78-3.32]. CONCLUSION: Implementation of an institutional process change utilizing prospective ECG-triggered dual-source end-systolic acquisition avoided the use of beta-blockers, significantly reduced patient appointment and scan times with acceptable diagnostic performance.

Emerging Pathway to a Precision Medicine Approach for Angina With Nonobstructive Coronary Arteries in Women.

Women are disproportionately affected by symptoms of angina with nonobstructive coronary arteries (ANOCA) which is associated with significant mortality and economic impact. Although distinct endotypes of ANOCA have been defined, it is underdiagnosed and is often incompletely characterized when identified. Patients are often unresponsive to traditional therapeutic options, which are typically antianginal, and the current ability to guide treatment modification by specific pathways is limited. Studies have associated specific genetic loci, transcriptomic features, and biomarkers with ANOCA. Such panomic data, in combination with known imaging and invasive diagnostic techniques, should be utilized to define more precise pathophysiologic subtypes of ANOCA in women, which will in turn help to identify targeted, effective therapies. A precision medicine-based approach to managing ANOCA incorporating these techniques in women has the potential to significantly improve their clinical care.

Cardiovascular testing recovery in Latin America one year into the COVID-19 pandemic: An analysis of data from an international longitudinal survey.

Background: The COVID-19 pandemic disproportionately impacted Latin America (LATAM), significantly disrupting cardiovascular testing. This study evaluated cardiac procedure recovery in LATAM one year after the outbreak. Methods: The International Atomic Energy Agency (IAEA) surveyed 669 centers in 107 countries worldwide, including 135 facilities in 19 LATAM countries, to assess cardiovascular procedure volumes in March 2019, April 2020, and April 2021, and changes in center practices and staffing conditions one year into the COVID-19 pandemic. Findings: LATAM centers reported a 21 % decrease in procedure volumes in April 2021 from pre-pandemic-baseline, vs. a 0 % change in the rest of the world (RoW), and greater volume reductions for almost all procedure types. Centers in Central America and Mexico reported the largest procedure reductions (47 % reduction) compared to the Caribbean (15 %), and South America (14 %, p = 0.01), and this LATAM region was a significant predictor of lower procedure recovery in multivariable regression. More LATAM centers reported reduced salaries and increased layoffs of clinical staff compared to RoW, and LATAM respondents estimated that half of physician and non-physician staff experienced excess psychological stress related to the pandemic, compared to 25 % and 30 % in RoW (p < 0.001). Conclusions: Cardiovascular testing recovery in LATAM trailed behind RoW for most procedure types, with centers in Central America and Mexico reporting the greatest volume reductions. This study found lasting impacts of COVID-19 on cardiovascular care in LATAM and the need for mental health support for LATAM healthcare workers in current and future pandemics.

Recovery Rates of Diagnostic Cardiac Procedural Volume in Oceania 1 Year Into COVID-19: The IAEA Non-Invasive Cardiology Protocol Survey on COVID-19 (INCAPS COVID 2).

AIM: The aim of this study was to assess the recovery rates of diagnostic cardiac procedure volumes in the Oceania Region, midway through the coronavirus disease 2019 (COVID-19) pandemic. METHODS: A survey was performed comparing procedure volumes between March 2019 (pre-pandemic), April 2020 (during first wave of COVID-19 pandemic), and April 2021 (1 year into the COVID-19 pandemic). A total of 31 health care facilities within Oceania that perform cardiac diagnostic procedures were surveyed, including a mixture of metropolitan and regional, hospital and outpatient, public and private sites, as well as teaching and non-teaching hospitals. A comparison was made with 549 centres in 96 countries in the rest of the world (RoW) outside of Oceania. The total number and median percentage change in procedure volume were measured between the three timepoints, compared by test type and by facility. RESULTS: A total of 11,902 cardiac diagnostic procedures were performed in Oceania in April 2021 as compared with 11,835 pre-pandemic in March 2019 and 5,986 in April 2020; whereas, in the RoW, 499,079 procedures were performed in April 2021 compared with 497,615 pre-pandemic in March 2019 and 179,014 in April 2020. There was no significant difference in the median recovery rates for total procedure volumes between Oceania (-6%) and the RoW (-3%) (p=0.81). While there was no statistically significant difference in percentage recovery been functional ischaemia testing and anatomical coronary testing in Oceania as compared with the RoW, there was, however, a suggestion of poorer recovery in anatomical coronary testing in Oceania as compared with the RoW (CT coronary angiography -16% in Oceania vs -1% in RoW, and invasive coronary angiography -20% in Oceania vs -9% in RoW). There was no statistically significant difference in recovery rates in procedure volume between metropolitan vs regional (p=0.44), public vs private (p=0.92), hospital vs outpatient (p=0.79), or teaching vs non-teaching centres (p=0.73). CONCLUSIONS: Total cardiology procedure volumes in Oceania normalised 1 year post-pandemic compared to pre-pandemic levels, with no significant difference compared with the RoW and between the different types of health care facilities.

Disparities in Noninvasive Traditional and Advanced Testing for Coronary Artery Disease: Findings from the INCAPS-COVID 2 Study.

The COVID-19 pandemic disrupted the delivery of cardiovascular care, including noninvasive testing protocols and test selection for the evaluation of coronary artery disease (CAD). Trends in test selection in traditional versus advanced noninvasive tests for CAD during the pandemic and in countries of varying income status have not been well studied. The International Atomic Energy Agency conducted a global survey to assess the pandemic-related changes in the practice of cardiovascular diagnostic testing. Site procedural volumes for noninvasive tests to evaluate CAD from March 2019 (prepandemic), April 2020 (onset), and April 2021 (initial recovery) were collected. We considered traditional testing modalities, such as exercise electrocardiography, stress echocardiography, and stress single-photon emission computed tomography, and advanced testing modalities, such as stress cardiac magnetic resonance, coronary computed tomography angiography, and stress positron emission tomography. Survey data were obtained from 669 centers in 107 countries, reporting the performance of 367,933 studies for CAD during the study period. Compared with 2019, traditional tests were performed 14% less frequently (recovery rate 82%) in 2021 versus advanced tests, which were performed 15% more frequently (128% recovery rate). Coronary computed tomography angiography, stress cardiac magnetic resonance, and stress positron emission tomography showed 14%, 25%, and 25% increases in volumes from 2019 to 2021, respectively. The increase in advanced testing was isolated to high- and upper middle-income countries, with 132% recovery in advanced tests by 2021 compared with 55% in lower income nations. The COVID-19 pandemic exacerbated economic disparities in CAD testing practice between wealthy and poorer countries. Greater recovery rates and even new growth were observed for advanced imaging modalities; however, this growth was restricted to wealthy countries. Efforts to reduce practice variations in CAD testing because of economic status are warranted.

ACR Appropriateness Criteria® Congenital or Acquired Heart Disease.

Pediatric heart disease is a large and diverse field with an overall prevalence estimated at 6 to 13 per 1,000 live births. This document discusses appropriateness of advanced imaging for a broad range of variants. Diseases covered include tetralogy of Fallot, transposition of great arteries, congenital or acquired pediatric coronary artery abnormality, single ventricle, aortopathy, anomalous pulmonary venous return, aortopathy and aortic coarctation, with indications for advanced imaging spanning the entire natural history of the disease in children and adults, including initial diagnosis, treatment planning, treatment monitoring, and early detection of complications. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Cardiovascular Testing in the United States during the COVID-19 Pandemic: Volume Recovery and Worldwide Comparison.

Purpose: To characterize the recovery of diagnostic cardiovascular procedure volumes in U.S. and non-U.S. facilities in the year following the initial COVID-19 outbreak. Materials and Methods: The International Atomic Energy Agency (IAEA) coordinated a worldwide study called the IAEA Noninvasive Cardiology Protocols Study of COVID-19 2 (INCAPS COVID 2), collecting data from 669 facilities in 107 countries, including 93 facilities in 34 U.S. states, to determine the impact of the pandemic on diagnostic cardiovascular procedure volumes. Participants reported volumes for each diagnostic imaging modality used at their facility for March 2019 (baseline), April 2020, and April 2021. This secondary analysis of INCAPS COVID 2 evaluated differences in changes in procedure volume between U.S. and non-U.S. facilities and among U.S. regions. Factors associated with return to prepandemic volumes in the United States were also analyzed in a multivariable regression analysis. Results: Reduction in procedure volumes in April 2020 compared with baseline was similar for U.S. and non-U.S. facilities (-66% vs -71%, P = .27). U.S. facilities reported greater return to baseline in April 2021 than did all non-U.S. facilities (4% vs -6%, P = .008), but there was no evidence of a difference when comparing U.S. facilities with non-U.S. high-income country (NUHIC) facilities (4% vs 0%, P = .18). U.S. regional differences in return to baseline were observed between the Midwest (11%), Northeast (9%), South (1%), and West (-7%, P = .03), but no studied factors were significant predictors of 2021 change from prepandemic baseline. Conclusion: The reductions in cardiac testing during the early pandemic have recovered within a year to prepandemic baselines in the United States and NUHICs, while procedure volumes remain depressed in lower-income countries.Keywords: SPECT, Cardiac, Epidemiology, Angiography, CT Angiography, CT, Echocardiography, SPECT/CT, MR Imaging, Radionuclide Studies, COVID-19, Cardiovascular Imaging, Diagnostic Cardiovascular Procedure, Cardiovascular Disease, Cardiac Testing Supplemental material is available for this article. © RSNA, 2023.

Relation of Gender to Atherosclerotic Plaque Characteristics by Differing Angiographic Stenosis Severity.

It is unknown whether gender influences the atherosclerotic plaque characteristics (APCs) of lesions of varying angiographic stenosis severity. This study evaluated the imaging data of 303 symptomatic patients from the derivation arm of the CREDENCE (Computed TomogRaphic Evaluation of Atherosclerotic Determinants of Myocardial IsChEmia) trial, all of whom underwent coronary computed tomographic angiography and clinically indicated nonemergent invasive coronary angiography upon study enrollment. Index tests were interpreted by 2 blinded core laboratories, one of which performed quantitative coronary computed tomographic angiography using an artificial intelligence application to characterize and quantify APCs, including percent atheroma volume (PAV), low-density noncalcified plaque (LD-NCP), noncalcified plaque (NCP), calcified plaque (CP), lesion length, positive arterial remodeling, and high-risk plaque (a combination of LD-NCP and positive remodeling ≥1.10); the other classified lesions as obstructive (≥50% diameter stenosis) or nonobstructive (<50% diameter stenosis) based on quantitative invasive coronary angiography. The relation between APCs and angiographic stenosis was further examined by gender. The mean age of the study cohort was 64.4 ± 10.2 years (29.0% female). In patients with obstructive disease, men had more LD-NCP PAV (0.5 ± 0.4 vs 0.3 ± 0.8, p = 0.03) and women had more CP PAV (11.7 ± 1.6 vs 8.0 ± 0.8, p = 0.04). Obstructive lesions had more NCP PAV compared with their nonobstructive lesions in both genders, however, obstructive lesions in women also demonstrated greater LD-NCP PAV (0.4 ± 0.5 vs 1.0 ± 1.8, p = 0.03), and CP PAV (17.4 ± 16.5 vs 25.9 ± 18.7, p = 0.03) than nonobstructive lesions. Comparing the composition of obstructive lesions by gender, women had more CP PAV (26.3 ± 3.4 vs 15.8 ± 1.5, p = 0.005) whereas men had more NCP PAV (33.0 ± 1.6 vs 26.7 ± 2.5, p = 0.04). Men had more LD-NCP PAV in nonobstructive lesions compared with women (1.2 ± 0.2 vs 0.6 ± 0.2, p = 0.02). In conclusion, there are gender-specific differences in plaque composition based on stenosis severity.

When Does a Calcium Score Equate to Secondary Prevention?: Insights From the Multinational CONFIRM Registry.

BACKGROUND: Elevated coronary artery calcium (CAC) scores in subjects without prior atherosclerotic cardiovascular disease (ASCVD) have been shown to be associated with increased cardiovascular risk. OBJECTIVES: The authors sought to determine at what level individuals with elevated CAC scores who have not had an ASCVD event should be treated as aggressively for cardiovascular risk factors as patients who have already survived an ASCVD event. METHODS: The authors performed a cohort study comparing event rates of patients with established ASVCD to event rates in persons with no history of ASCVD and known calcium scores to ascertain at what level elevated CAC scores equate to risk associated with existing ASCVD. In the multinational CONFIRM (Coronary CT Angiography Evaluation for Clinical Outcomes: An International Multicenter) registry, the authors compared ASCVD event rates in persons without a history of myocardial infarction (MI) or revascularization (as categorized on CAC scores) to event rates in those with established ASCVD. They identified 4,511 individuals without known coronary artery disease (CAC) who were compared to 438 individuals with established ASCVD. CAC was categorized as 0, 1 to 100, 101 to 300, and >300. Cumulative major adverse cardiovascular events (MACE), MACE plus late revascularization, MI, and all-cause mortality incidence was assessed using the Kaplan-Meier method for persons with no ASCVD history by CAC level and persons with established ASCVD. Cox proportional hazards regression analysis was used to calculate HRs with 95% CIs, which were adjusted for traditional cardiovascular risk factors. RESULTS: The mean age was 57.6 ± 12.4 years (56% male). In total, 442 of 4,949 (9%) patients experienced MACEs over a median follow-up of 4 years (IQR: 1.7-5.7 years). Incident MACEs increased with higher CAC scores, with the highest rates observed with CAC score >300 and in those with prior ASCVD. All-cause mortality, MACEs, MACE + late revascularization, and MI event rates were not statistically significantly different in those with CAC >300 compared with established ASCVD (all P > 0.05). Persons with a CAC score <300 had substantially lower event rates. CONCLUSIONS: Patients with CAC scores >300 are at an equivalent risk of MACE and its components as those treated for established ASCVD. This observation, that those with CAC >300 have event rates comparable to those with established ASCVD, supplies important background for further study related to secondary prevention treatment targets in subjects without prior ASCVD with elevated CAC. Understanding the CAC scores that are associated with ASCVD risk equivalent to stable secondary prevention populations may be important for guiding the intensity of preventive approaches more broadly.

Sex and age-specific interactions of coronary atherosclerotic plaque onset and prognosis from coronary computed tomography.

AIMS: The totality of atherosclerotic plaque derived from coronary computed tomography angiography (CCTA) emerges as a comprehensive measure to assess the intensity of medical treatment that patients need. This study examines the differences in age onset and prognostic significance of atherosclerotic plaque burden between sexes. METHODS AND RESULTS: From a large multi-center CCTA registry the Leiden CCTA score was calculated in 24 950 individuals. A total of 11 678 women (58.5 ± 12.4 years) and 13 272 men (55.6 ± 12.5 years) were followed for 3.7 years for major adverse cardiovascular events (MACE) (death or myocardial infarction). The age where the median risk score was above zero was 12 years higher in women vs. men (64-68 years vs. 52-56 years, respectively, P < 0.001). The Leiden CCTA risk score was independently associated with MACE: score 6-20: HR 2.29 (1.69-3.10); score > 20: HR 6.71 (4.36-10.32) in women, and score 6-20: HR 1.64 (1.29-2.08); score > 20: HR 2.38 (1.73-3.29) in men. The risk was significantly higher for women within the highest score group (adjusted P-interaction = 0.003). In pre-menopausal women, the risk score was equally predictive and comparable with men. In post-menopausal women, the prognostic value was higher for women [score 6-20: HR 2.21 (1.57-3.11); score > 20: HR 6.11 (3.84-9.70) in women; score 6-20: HR 1.57 (1.19-2.09); score > 20: HR 2.25 (1.58-3.22) in men], with a significant interaction for the highest risk group (adjusted P-interaction = 0.004). CONCLUSION: Women developed coronary atherosclerosis approximately 12 years later than men. Post-menopausal women within the highest atherosclerotic burden group were at significantly higher risk for MACE than their male counterparts, which may have implications for the medical treatment intensity.

Contemporary cardiovascular computed tomography (CCT) training: Serial surveys of the international CCT community by the Fellow and Resident Leaders of the Society of Cardiovascular Computed Tomography (SCCT) Committee (FiRST) and SCCT Future Leaders Program (FLP).

BACKGROUND: As cardiovascular computed tomography (CCT) practice evolves, the demand for specialists continues to increase. However, CCT training remains variable globally with limited contemporaneous data to understand this heterogeneity. We sought to understand the role of CCT globally and the training available to underpin its use. METHODS: We performed two consecutive surveys of cardiology and radiology physicians, two years apart, utilizing the Society of Cardiovascular Computed Tomography (SCCT) website, weblinks, social media platforms, and meeting handouts to maximize our response rate. We compared United States (US)-based vs. international responses to understand global similarities and differences in practice and training in the surveys. RESULTS: 235 respondents (37% trainees and 63% educators/non-trainees) initiated the first survey with 174 (74%) completing the core survey, with 205 providing their work location (114 US and 91 international). Eighty-four percent (92/110) of educator respondents stated a need for increased training opportunities to meet growing demand. Dedicated training fellowships are heterogenous, with limited access to structural heart imaging training, despite structural scanning being performed within institutions. The lack of a standardized curriculum was identified as the main obstacle to effective CCT learning, particularly in the US, with web-based learning platforms being the most popular option for improving access to CCT training. 148 trainees initiated the second survey with 107 (72%) completing the core components (51% North America, 49% international). Only 68% said they would be able to meet their required CCT education needs via their training program. Obstacles in obtaining CCT training again included a lack of a developed curriculum (51%), a lack of dedicated training time (35%), and a lack of local faculty expertise (31%). There was regional variability in access to CCT training, and, in contrast to the first survey, most (89%) felt 1:1 live review of cases with trained/expert reader was most useful for improving CCT training alongside formal curriculum/live lectures (72%). CONCLUSIONS: There is a need to expand dedicated CCT training globally to meet the demand for complex CCT practice. Access to CCT education (didactic and 1:1 case-based teaching from expert faculty), implementation of recently published global training curricula, and increased teaching resources (web-based) as an adjunct to existing experiential learning opportunities, are all deemed necessary to address current educational shortfalls.

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.

Influence of BMI on virtual coronary artery calcium scoring.

PURPOSE: Virtual non-contrast (VNC) coronary artery calcium scoring (CAC) may obviate the need for traditional non-contrast (TNC) CAC. There is no data on the influence of body mass index (BMI) on VNC reliability. We aimed to evaluate the influence of BMI on VNC CAC agreement with TNC. MATERIALS AND METHODS: All patients who underwent sequential CAC and coronary CT angiography (CCTA) using spectral CT with TNC CAC > 0 between August 2020 and December 2021 were included. Agatston CAC scores were calculated manually by 2 blinded readers from VNC scans. A correction factor was calculated from the slope of the linear regression using the method of least squares and applied to the VNC scores. Bland-Altman plots and Cohen's weighted Kappa were utilized. RESULTS: We included 174 patients (57.5% female). Mean BMI was 32.6 ± 7.02 kg/m2 [BMI < 30 (39.7%); BMI 30-40 (45.4%); and BMI > 40 kg/m2 (14.9%)]. Mean TNC CAC was 177.8 ± 316.86 and mean VNC CAC after applying the correction factor 149.34 ± 296.73. The TNC value strongly correlated with VNC (r = 0.94; p < 0.0001). As BMI increased there was a progressive reduction in signal-to-noise ratio, contrast-to-noise ratio and coronary enhancement (p < 0.05). The degree of agreement between VNC and TNC CAC decreased as BMI increased (agreement = 91.79 (weighted Kappa = 0.72), 91.14 (weighted Kappa = 0.58) and 88.46% (weighted Kappa = 0.48) (all P values < 0.001) for BMI < 30; 30-40 and > 40 kg/m2, respectively). CONCLUSION: BMI has a significant influence on the accuracy of VNC CAC. VNC CAC shows substantial agreement in non-obese patients but performs poorly in BMI > 40 kg/m2. This is the first study to evaluate the influence of body mass index (BMI) on virtual non-contrast (VNC) coronary artery calcium scoring (CAC) as compared to traditional non-contrast (TNC). We retrospectively evaluated 174 patients with TNC CAC and two blinded reviewers manually calculated the VNC CAC. All cases were included without specific selection for quality. The ratio between the two directly proportional values was determined using the slope from the linear regression through the method of least squares. This correction factor of 2.65 was applied to the calcium scores obtained from VNC images. We found that VNC CAC shows substantial risk-class agreement with TNC in non-obese patients (agreement = 91.79 and weighted Kappa = 0.72) but performs poorly in BMI > 40 kg/m2 (agreement: 88.46% and weighted Kappa = 0.48). These findings show the potential use of VNC CAC to avoid additional radiation in non-obese patients. However, further research on potential improvement strategies for VNC CAC in obese patients is needed.

Diabetes, Atherosclerosis, and Stenosis by AI.

OBJECTIVE: This study evaluates the relationship between atherosclerotic plaque characteristics (APCs) and angiographic stenosis severity in patients with and without diabetes. Whether APCs differ based on lesion severity and diabetes status is unknown. RESEARCH DESIGN AND METHODS: We retrospectively evaluated 303 subjects from the Computed TomogRaphic Evaluation of Atherosclerotic Determinants of Myocardial IsChEmia (CREDENCE) trial referred for invasive coronary angiography with coronary computed tomographic angiography (CCTA) and classified lesions as obstructive (≥50% stenosed) or nonobstructive using blinded core laboratory analysis of quantitative coronary angiography. CCTA quantified APCs, including plaque volume (PV), calcified plaque (CP), noncalcified plaque (NCP), low-density NCP (LD-NCP), lesion length, positive remodeling (PR), high-risk plaque (HRP), and percentage of atheroma volume (PAV; PV normalized for vessel volume). The relationship between APCs, stenosis severity, and diabetes status was assessed. RESULTS: Among the 303 patients, 95 (31.4%) had diabetes. There were 117 lesions in the cohort with diabetes, 58.1% of which were obstructive. Patients with diabetes had greater plaque burden (P = 0.004). Patients with diabetes and nonobstructive disease had greater PV (P = 0.02), PAV (P = 0.02), NCP (P = 0.03), PAV NCP (P = 0.02), diseased vessels (P = 0.03), and maximum stenosis (P = 0.02) than patients without diabetes with nonobstructive disease. APCs were similar between patients with diabetes with nonobstructive disease and patients without diabetes with obstructive disease. Diabetes status did not affect HRP or PR. Patients with diabetes had similar APCs in obstructive and nonobstructive lesions. CONCLUSIONS: Patients with diabetes and nonobstructive stenosis had an association to similar APCs as patients without diabetes who had obstructive stenosis. Among patients with nonobstructive disease, patients with diabetes had more total PV and NCP.