Prospective Deep Learning-based Quantitative Assessment of Coronary Plaque by CT Angiography Compared with Intravascular Ultrasound.

AIMS: Coronary computed tomography angiography provides noninvasive assessment of coronary stenosis severity and flow impairment. Automated artificial intelligence analysis may assist in precise quantification and characterization of coronary atherosclerosis, enabling patient-specific risk determination and management strategies. This multicenter international study compared an automated deep-learning-based method for segmenting coronary atherosclerosis in coronary computed tomography angiography (CCTA) against the reference standard of intravascular ultrasound (IVUS). METHODS AND RESULTS: The study included clinically stable patients with known coronary artery disease from 15 centers in the U.S. and Japan. An artificial intelligence (AI)-enabled plaque analysis service was utilized to quantify and characterize total plaque (TPV), vessel, lumen, calcified plaque (CP), non-calcified plaque (NCP), and low attenuation plaque (LAP) volumes derived from CCTA and compared with IVUS measurements in a blinded, core laboratory-adjudicated fashion. In 237 patients, 432 lesions were assessed; mean lesion length was 24.5 mm. Mean IVUS-TPV was 186.0 mm3. AI-enabled plaque analysis on CCTA showed strong correlation and high accuracy when compared with IVUS; correlation coefficient, slope, and Y intercept for TPV were 0.91, 0.99, and 1.87, respectively; for CP volume 0.91, 1.05, and 5.32, respectively; and for NCP volume 0.87, 0.98, and 15.24, respectively. Bland-Altman analysis demonstrated strong agreement with little bias for these measurements. CONCLUSIONS: Artificial intelligence enabled CCTA quantification and characterization of atherosclerosis demonstrated strong agreement with IVUS reference standard measurements. This tool may prove effective for accurate evaluation of coronary atherosclerotic burden and cardiovascular risk assessment.[ClinicalTrails.gov identifier: NCT05138289].

Coronary computed tomography angiography-based SYNTAX score for comprehensive assessment of advanced coronary artery disease.

BACKGROUND: Since the initial attempt to adapt the anatomical SYNTAX score (aSS) to coronary computed tomography angiography (CCTA), CCTA imaging technology has evolved, and is currently used as a "decision-maker" for revascularization strategy in complex coronary artery disease (CAD) and has rendered necessary some updating of the aSS to the CCTA modality. OBJECTIVES: The aim is to provide updated definitions of the aSS derived from CCTA in patients with complex CAD undergoing CABG. METHODS: The modifications of CCTA-aSS are the following; (i) updated definition and detection criteria of total occlusion (TO) in CCTA based on length assessment, (ii) inclusion of scoring points for serial bifurcations located in one single coronary segment. (iii) inclusion of weighing score points for lesions located distal to a TO, not visualized on conventional coronary angiography, but visible in CCTA, (iv) removal of thrombus and bridging collateral items from the weighing score, considering the limited diagnostic capability of CCTA in detecting these specific lesion characteristics. RESULTS: the updated CCTA-aSS was tested in a first-in-man study using the sole guidance of CCTA for the planning and performance of bypass surgery in complex CAD (n â€‹= â€‹114). An interobserver analysis showed excellent reproducibility (ICC â€‹= â€‹0.96, 95 â€‹% confidence interval 0.94-0.97). CONCLUSION: The updated CCTA-aSS was implemented in a cohort of patients with complex CAD undergoing CABG with the sole guidance of CCTA and FFRCT and the Inter-reproducibility of the analysis of the updated score was found excellent. The prognostic value of the modified CCTA-aSS will be examined in future studies.

Clinical and cost implications of deferred testing in low-risk patients with stable chest pain: a simulation using the PROMISE trial.

Current guidelines recommend a deferred testing approach in low-risk patients presenting with stable chest pain. After simulating a deferred testing approach using the PROMISE Minimal Risk Score to identify 915 minimal risk participants with cost data from the PROMISE trial, a deferred testing strategy was associated with an adjusted cost savings of -$748.74 (95% CI: -1646.97, 158.06) per participant and 74.6% of samples had better clinical outcomes and lower mean cost. This supports the current guideline recommended deferred testing approach in low-risk patients with stable chest pain.

Non-invasive Heart Team assessment of multivessel coronary disease with coronary computed tomography angiography based on SYNTAX score II treatment recommendations: design and rationale of the randomised SYNTAX III Revolution trial.

AIMS: The aim of this study was to investigate whether a Heart Team decision-making process regarding the choice of revascularisation strategy based on non-invasive coronary multislice computed tomography angiography (MSCT) assessment of coronary artery disease (CAD) is equivalent to the standard-of-care invasive angiography-based assessment in patients with multivessel CAD. METHODS AND RESULTS: The SYNTAX III Revolution trial is a prospective, multicentre, all-comers randomised trial that will randomise two Heart Teams to select between surgical and percutaneous treatment according to either an invasive conventional angiography or a non-invasive MSCT angiography assessment in patients with multivessel CAD. The treatment selection by each Heart Team will be guided by the SYNTAX score II calculation. The primary endpoint is the level of agreement according to kappa of the initial decision by the Heart Teams on the modality of the revascularisation based on MSCT and angiography assessments. Secondary endpoints include agreement on the number of vessels requiring treatment and the coronary segments in need of revascularisation. CONCLUSIONS: The SYNTAX III Revolution trial will provide valuable information regarding the ability of a purely non-invasive coronary anatomy assessment to select accurately the most appropriate revascularisation strategy for patients with multivessel CAD.

Quality-of-Life and Economic Outcomes of Assessing Fractional Flow Reserve With Computed Tomography Angiography: PLATFORM.

BACKGROUND: Fractional flow reserve estimated using computed tomography (FFRCT) might improve evaluation of patients with chest pain. OBJECTIVES: The authors sought to determine the effect on cost and quality of life (QOL) of using FFRCT instead of usual care to evaluate stable patients with symptoms suspicious for coronary disease. METHODS: Symptomatic patients without known coronary disease were enrolled into 2 strata based on whether invasive or noninvasive diagnostic testing was planned. In each stratum, consecutive observational cohorts were evaluated with either usual care or FFRCT. The number of diagnostic tests, invasive procedures, hospitalizations, and medications during 90-day follow-up were multiplied by U.S. cost weights and summed to derive total medical costs. Changes in QOL from baseline to 90 days were assessed using the Seattle Angina Questionnaire, the EuroQOL, and a visual analog scale. RESULTS: In the 584 patients, 74% had atypical angina, and the pre-test probability of coronary disease was 49%. In the planned invasive stratum, mean costs were 32% lower among the FFRCT patients than among the usual care patients ($7,343 vs. $10,734 p < 0.0001). In the noninvasive stratum, mean costs were not significantly different between the FFRCT patients and the usual care patients ($2,679 vs. $2,137; p = 0.26). In a sensitivity analysis, when the cost weight of FFRCT was set to 7 times that of computed tomography angiography, the FFRCT group still had lower costs than the usual care group in the invasive testing stratum ($8,619 vs. $ 10,734; p < 0.0001), whereas in the noninvasive testing stratum, when the cost weight of FFRCT was set to one-half that of computed tomography angiography, the FFRCT group had higher costs than the usual care group ($2,766 vs. $2,137; p = 0.02). Each QOL score improved in the overall study population (p < 0.0001). In the noninvasive stratum, QOL scores improved more in FFRCT patients than in usual care patients: Seattle Angina Questionnaire 19.5 versus 11.4, p = 0.003; EuroQOL 0.08 versus 0.03, p = 0.002; and visual analog scale 4.1 versus 2.3, p = 0.82. In the invasive cohort, the improvements in QOL were similar in the FFRCT and usual care patients. CONCLUSIONS: An evaluation strategy based on FFRCT was associated with less resource use and lower costs within 90 days than evaluation with invasive coronary angiography. Evaluation with FFRCT was associated with greater improvement in quality of life than evaluation with usual noninvasive testing. (Prospective Longitudinal Trial of FFRCT: Outcomes and Resource Impacts [PLATFORM]; NCT01943903).

Rationale and design of the Prospective LongitudinAl Trial of FFRCT: Outcome and Resource IMpacts study.

BACKGROUND: Fractional flow reserve (FFR) measured by coronary computed tomography angiography (FFRCT) has been validated against invasive FFR. However, there are no data on how the use of FFRCT affects patient care and outcomes. The aim of this study is to compare standard practice guided by usual care testing to FFRCT-guided management in symptomatic subjects with suspected coronary artery disease (CAD). METHODS: In this prospective nonrandomized trial, symptomatic patients with suspected CAD will be enrolled in 2 consecutive cohorts: a usual care-guided pathway (cohort 1) and an FFRCT-guided pathway (cohort 2). Each cohort is divided into 2 groups according to whether noninvasive or invasive diagnostic testing was planned before enrollment. In all subjects, the patient's clinical team will review all diagnostic test results and determine a treatment strategy. A total sample size of 580 subjects will be enrolled and followed up for 12 months. RESULTS: The primary end point is the comparison of the percentage of patients with planned invasive testing who have a catheterization (invasive coronary angiography) within 90 days from initial assessment, which does not show a significant stenosis (defined as coronary artery stenosis >50% or invasive FFR ≤0.80). Secondary end points include the rate of invasive coronary angiography without obstructive CAD in those with planned noninvasive testing and, in all groups, noninferiority of resource use, quality of life, medical radiation exposure, and major adverse cardiac events up to 365 days of follow-up. CONCLUSIONS: The study compares clinical and economic outcomes based on diagnostic evaluation using FFRCT with that based on standard diagnostic strategies.