Utility of Artificial Intelligence Plaque Quantification: Results of the DECODE Study.

Background: Artificial Intelligence Plaque Analysis (AI-QCPA, HeartFlow) provides, from a CCTA, quantitative plaque burden information including total plaque and plaque subtype volumes. We sought to evaluate the clinical utility of AI-QCPA in clinical decision making. Methods: One hundred cases were reviewed by 3 highly experienced practicing cardiologists who are SCCT level 3 CCTA readers. Patients had varying levels of calcium (median CACS: 99.5) and CAD-RADS scores. Initial management plan for each case was a majority decision based upon patient demographics, clinical history, and CCTA report. AI-QCPA was then provided for each patient, and the plan was reconsidered. The primary endpoint was the reclassification rate (RR). In a secondary analysis of 40 cases, the above process was repeated but the initial plan was based upon review of the actual CCTA images. Results: RR following AI-QCPA review was 66% (66/100) of cases (95% CI, 56.72%-75.28%). RR ranged from 47% in cases with CACS 0 to 96% in cases with CACS >400, and from 40% in CAD-RADS 1 cases to 94% in CAD-RADS 4 cases. RR was higher in cases with coronary stenoses ≥50% (89.5%) vs cases with stenoses <50% (51.6%). RR was 39% in cases with LDL <70 mg/dL vs 70% in LDL ≥70 mg/dL. Following review of the CCTA images rather than the CCTA report, the RR was 50% (95% CI of 34.51% - 65.49%). The primary reclassification effect was to intensify preventative medical therapy. Conclusions: Adding AI-QCPA to CCTA alone leads to a change in clinical care in two-thirds of patients.

Completeness of revascularization by FFRCT in stable angina: Association to adverse cardiovascular outcomes.

BACKGROUND: The prognostic impact of complete coronary revascularization relative to non-invasive testing methods is unknown. OBJECTIVES: To assess the association between completeness of revascularization defined by CTA-derived fractional flow reserve (FFRCT) and cardiovascular outcomes in patients with stable angina. METHODS: Multicenter 3-year follow-up study of patients with new onset stable angina and ≥ 30% stenosis by CTA. The lesion-specific FFRCT value (two cm-distal-to-stenosis) was registered in all vessels with stenosis and considered abnormal when ≤ 0.80. Patients with FFRCT ≤ 0.80 were categorized as: Completely revascularized (CR-FFRCT), all vessels with FFRCT ≤ 0.80 revascularized; incompletely revascularized (IR-FFRCT), ≥ 1 vessels with FFRCT ≤ 0.80 non-revascularized. Early revascularization (< 90 days from index CTA) categorized vessels as revascularized. The primary endpoint comprised cardiovascular death and non-fatal myocardial infarction; the secondary endpoint vessel-specific late revascularization and non-fatal myocardial infarction. RESULTS: Amongst 900 patients and 1759 vessels, FFRCT was ≤ 0.80 in 377 (42%) patients, 536 (30%) vessels; revascularization was performed in 244 (27%) patients, 340 (19%) vessels. Risk of the primary endpoint was higher for IR-FFRCT (15/210 [7.1%]) compared to CR-FFRCT (4/167 [2.4%]), RR: 2.98; 95% CI: 1.01-8.8, p â€‹= â€‹0.036, and to normal FFRCT (3/523 [0.6%]), RR: 12.45; 95% CI: 3.6-42.6, p â€‹< â€‹0.001. Incidence of the secondary endpoint was higher in non-revascularized vessels with FFRCT ≤ 0.80 (29/250 [12%]) compared to revascularized vessels with FFRCT ≤ 0.80 (5/286 [1.7%]), p â€‹= â€‹0.001, and to vessels with FFRCT > 0.80 (10/1223 [0.8%]), p â€‹< â€‹0.001. CONCLUSION: Incomplete revascularization of patients with lesion-specific FFRCT ≤ 0.80 is associated to unfavorable cardiovascular outcomes compared to those with complete revascularization or FFRCT > 0.80.

Sex Differences in Coronary Artery Disease Characteristics Among Patients With Type 2 Myocardial Infarction.

Background: Type 2 myocardial infarction (MI) results from coronary supply and demand imbalance and has a poor prognosis. It is crucial to identify potential sex-based differences in the prevalence and nature of coronary artery disease (CAD) within this population. Objectives: The purpose of this study was to evaluate sex-based disease differences in type 2 MI among patients evaluated with coronary computed tomography angiography and fractional flow reserve. Methods: In a single-center, prospective study, patients with strictly adjudicated type 2 MI underwent coronary computed tomography angiography with fractional flow reserve. Results: Among 50 study participants enrolled, 50% were women. A similar mix of MI precipitants was present in both sexes. ST-segment depression was more common in women (64% vs 32%), while men were more likely to have T wave inversion (68% vs 36%). Women and men had comparable coronary artery calcium scores (median: 152 [Q1, Q3: 45, 762] vs 234 [Q1, Q3: 56, 422]). Prevalence of any CAD (84% vs 100%), obstructive CAD (24% vs 28%), and hemodynamically significant focal stenosis (20% vs 32%) were similar between sexes. Total plaque volume was similar between sexes, but women had significantly lower levels of low-attenuation plaque (median: 3 [Q1, Q3: 1, 7] vs 9 [Q1, Q3: 3, 14]). Conclusions: Among patients with type 2 MI, prevalence of any CAD and obstructive CAD did not differ according to sex. Total plaque volume was similar between sexes, but women had a lower volume of low-attenuation plaque (DEFINing the PrEvalence and Characteristics of Coronary Artery Disease Among Patients With TYPE 2 Myocardial Infarction Using CT-FFR [DEFINE TYPE2MI]; NCT04864119).

Prospective deep learning-based quantitative assessment of coronary plaque by computed tomography angiography compared with intravascular ultrasound: the REVEALPLAQUE study.

AIMS: Coronary computed tomography angiography provides non-invasive assessment of coronary stenosis severity and flow impairment. Automated artificial intelligence (AI) analysis may assist in precise quantification and characterization of coronary atherosclerosis, enabling patient-specific risk determination and management strategies. This multicentre 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 centres in the USA and Japan. An AI-enabled plaque analysis 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, and 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. CONCLUSION: AI-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.

Interaction of AI-Enabled Quantitative Coronary Plaque Volumes on Coronary CT Angiography, FFRCT, and Clinical Outcomes: A Retrospective Analysis of the ADVANCE Registry.

BACKGROUND: Luminal stenosis, computed tomography-derived fractional-flow reserve (FFRCT), and high-risk plaque features on coronary computed tomography angiography are all known to be associated with adverse clinical outcomes. The interactions between these variables, patient outcomes, and quantitative plaque volumes have not been previously described. METHODS: Patients with coronary computed tomography angiography (n=4430) and one-year outcome data from the international ADVANCE (Assessing Diagnostic Value of Noninvasive FFRCT in Coronary Care) registry underwent artificial intelligence-enabled quantitative coronary plaque analysis. Optimal cutoffs for coronary total plaque volume and each plaque subtype were derived using receiver-operator characteristic curve analysis. The resulting plaque volumes were adjusted for age, sex, hypertension, smoking status, type 2 diabetes, hyperlipidemia, luminal stenosis, distal FFRCT, and translesional delta-FFRCT. Median plaque volumes and optimal cutoffs for these adjusted variables were compared with major adverse cardiac events, late revascularization, a composite of the two, and cardiovascular death and myocardial infarction. RESULTS: At one year, 55 patients (1.2%) had experienced major adverse cardiac events, and 123 (2.8%) had undergone late revascularization (>90 days). Following adjustment for age, sex, risk factors, stenosis, and FFRCT, total plaque volume above the receiver-operator characteristic curve-derived optimal cutoff (total plaque volume >564 mm3) was associated with the major adverse cardiac event/late revascularization composite (adjusted hazard ratio, 1.515 [95% CI, 1.093-2.099]; P=0.0126), and both components. Total percent atheroma volume greater than the optimal cutoff was associated with both major adverse cardiac event/late revascularization (total percent atheroma volume >24.4%; hazard ratio, 2.046 [95% CI, 1.474-2.839]; P<0.0001) and cardiovascular death/myocardial infarction (total percent atheroma volume >37.17%, hazard ratio, 4.53 [95% CI, 1.943-10.576]; P=0.0005). Calcified, noncalcified, and low-attenuation percentage atheroma volumes above the optimal cutoff were associated with all adverse outcomes, although this relationship was not maintained for cardiovascular death/myocardial infarction in analyses stratified by median plaque volumes. CONCLUSIONS: Analysis of the ADVANCE registry using artificial intelligence-enabled quantitative plaque analysis shows that total plaque volume is associated with one-year adverse clinical events, with incremental predictive value over luminal stenosis or abnormal physiology by FFRCT. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02499679.

Impact of Smoking on Coronary Volume-to-Myocardial Mass Ratio: An ADVANCE Registry Substudy.

Purpose To examine the relationship between smoking status and coronary volume-to-myocardial mass ratio (V/M) among individuals with coronary artery disease (CAD) undergoing CT fractional flow reserve (CT-FFR) analysis. Materials and Methods In this secondary analysis, participants from the ADVANCE registry evaluated for suspected CAD from July 15, 2015, to October 20, 2017, who were found to have coronary stenosis of 30% or greater at coronary CT angiography (CCTA) were included if they had known smoking status and underwent CT-FFR and V/M analysis. CCTA images were segmented to calculate coronary volume and myocardial mass. V/M was compared between smoking groups, and predictors of low V/M were determined. Results The sample for analysis included 503 current smokers, 1060 former smokers, and 1311 never-smokers (2874 participants; 1906 male participants). After adjustment for demographic and clinical factors, former smokers had greater coronary volume than never-smokers (former smokers, 3021.7 mm3 ± 934.0 [SD]; never-smokers, 2967.6 mm3 ± 978.0; P = .002), while current smokers had increased myocardial mass compared with never-smokers (current smokers, 127.8 g ± 32.9; never-smokers, 118.0 g ± 32.5; P = .02). However, both current and former smokers had lower V/M than never-smokers (current smokers, 24.1 mm3/g ± 7.9; former smokers, 24.9 mm3/g ± 7.1; never-smokers, 25.8 mm3/g ± 7.4; P < .001 [unadjusted] and P = .002 [unadjusted], respectively). Current smoking status (odds ratio [OR], 0.74 [95% CI: 0.59, 0.93]; P = .009), former smoking status (OR, 0.81 [95% CI: 0.68, 0.97]; P = .02), stenosis of 50% or greater (OR, 0.62 [95% CI: 0.52, 0.74]; P < .001), and diabetes (OR, 0.67 [95% CI: 0.56, 0.82]; P < .001) were independent predictors of low V/M. Conclusion Both current and former smoking status were independently associated with low V/M. Keywords: CT Angiography, Cardiac, Heart, Ischemia/Infarction Clinical trial registration no. NCT02499679 Supplemental material is available for this article. © RSNA, 2024.

Coronary computed tomography angiography derived fractional flow reserve and risk of recurrent angina: A 3-year follow-up study.

BACKGROUND: The association between coronary computed tomography angiography (CTA) derived fractional flow reserve (FFRCT) and risk of recurrent angina in patients with new onset stable angina pectoris (SAP) and stenosis by CTA is uncertain. METHODS: Multicenter 3-year follow-up study of patients presenting with symptoms suggestive of new onset SAP who underwent first-line CTA evaluation and subsequent standard-of-care treatment. All patients had at least one ≥30 â€‹% coronary stenosis. A per-patient lowest FFRCT-value ≤0.80 represented an abnormal test result. Patients with FFRCT ≤0.80 who underwent revascularization were categorized according to completeness of revascularization: 1) Completely revascularized (CR-FFRCT), all vessels with FFRCT ≤0.80 revascularized; or 2) incompletely revascularized (IR-FFRCT) ≥1 vessels with FFRCT ≤0.80 non-revascularized. Recurrent angina was evaluated using the Seattle Angina Questionnaire. RESULTS: Amongst 769 patients (619 [80 â€‹%] stenosis ≥50 â€‹%, 510 [66 â€‹%] FFRCT ≤0.80), 174 (23 â€‹%) reported recurrent angina at follow-up. An FFRCT ≤0.80 vs â€‹> â€‹0.80 associated to increased risk of recurrent angina, relative risk (RR): 1.82; 95 â€‹% CI: 1.31-2.52, p â€‹< â€‹0.001. Risk of recurrent angina in CR-FFRCT (n â€‹= â€‹135) was similar to patients with FFRCT >0.80, 13 â€‹% vs 15 â€‹%, RR: 0.93; 95 â€‹% CI: 0.62-1.40, p â€‹= â€‹0.72, while IR-FFRCT (n â€‹= â€‹90) and non-revascularized patients with FFRCT ≤0.80 (n â€‹= â€‹285) had increased risk, 37 â€‹% vs 15 â€‹% RR: 2.50; 95 â€‹% CI: 1.68-3.73, p â€‹< â€‹0.001 and 30 â€‹% vs 15 â€‹%, RR: 2.03; 95 â€‹% CI: 1.44-2.87, p â€‹< â€‹0.001, respectively. Use of antianginal medication was similar across study groups. CONCLUSION: In patients with SAP and coronary stenosis by CTA undergoing standard-of-care guided treatment, FFRCT provides information regarding risk of recurrent angina.

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.

Derivation and validation of a novel functional FFRCT score incorporating the burden of coronary stenosis severity and flow impairment to predict clinical events.

BACKGROUND: A score combining the burden of stenosis severity on coronary computed tomography angiography (CCTA) and flow impairment by fractional flow reserve derived from computed tomography (FFRCT) may be a better predictor of clinical events than either parameter alone. METHODS: The Functional FFRCT Score (FFS) combines CCTA and FFRCT parameters in an allocated point-based system. The feasibility of the FFS was assessed in cohort of 72 stable chest pain patients with matched CCTA and FFRCT datasets. Validation was performed using 2 cohorts: (a) 4468 patients from the ADVANCE Registry to define its association with revascularization and major adverse cardiovascular events (MACE); (b) 212 patients from the FORECAST trial to determine predictors of MACE. RESULTS: The median calculation time for the FFS was 10 (interquartile range 6-17) seconds, with strong intra-operator and inter-operator agreement (Cohen's Kappa 0.89 (±0.37, p â€‹< â€‹0.001) and 0.83 (±0.04, p â€‹< â€‹0.001, respectively). The FFS correlated strongly with both the CT-SYNTAX and the Functional CT-SYNTAX scores (rS â€‹= â€‹0.808 for both, p â€‹< â€‹0.001). In the ADVANCE cohort the FFS had good discriminatory abilities for revascularization with an area under the curve of 0.82, 95 â€‹% confidence interval (CI) 0.81-0.84, p â€‹< â€‹0.001. Patients in the highest FFS tertile had significantly higher rates of revascularization (61 â€‹% vs 5 â€‹%, p â€‹< â€‹0.001) and MACE (1.9 â€‹% vs 0.5 â€‹%, p â€‹= â€‹0.001) compared with the lowest FFS tertile. In the FORECAST cohort the FFS was an independent predictor of MACE at 9-month follow-up (hazard ratio 1.04, 95 â€‹% CI 1.01-1.08, p â€‹< â€‹0.01). CONCLUSION: The FFS is a quick-to-calculate and reproducible score, associated with revascularization and MACE in two distinct populations of stable symptomatic patients.

Impact of Coronary CT Angiography-derived Fractional Flow Reserve on Downstream Management and Clinical Outcomes in Individuals with and without Diabetes.

Purpose: To compare the clinical use of coronary CT angiography (CCTA)-derived fractional flow reserve (FFR) in individuals with and without diabetes mellitus (DM). Materials and Methods: This secondary analysis included participants (enrolled July 2015 to October 2017) from the prospective, multicenter, international The Assessing Diagnostic Value of Noninvasive CT-FFR in Coronary Care (ADVANCE) registry (ClinicalTrials.gov identifier, NCT02499679) who were evaluated for suspected coronary artery disease (CAD), with one or more coronary stenosis ≥30% on CCTA images, using CT-FFR. CCTA and CT-FFR findings, treatment strategies at 90 days, and clinical outcomes at 1-year follow-up were compared in participants with and without DM. Results: The study included 4290 participants (mean age, 66 years ± 10 [SD]; 66% male participants; 22% participants with DM). Participants with DM had more obstructive CAD (one or more coronary stenosis ≥50%; 78.8% vs 70.6%, P < .001), multivessel CAD (three-vessel obstructive CAD; 18.9% vs 11.2%, P < .001), and proportionally more vessels with CT-FFR ≤ 0.8 (74.3% vs 64.6%, P < .001). Treatment reclassification by CT-FFR occurred in two-thirds of participants which was consistent regardless of the presence of DM. There was a similar graded increase in coronary revascularization with declining CT-FFR in both groups. At 1 year, presence of DM was associated with higher rates of major adverse cardiovascular events (hazard ratio, 2.2; 95% CI: 1.2, 4.1; P = .01). However, no between group differences were observed when stratified by stenosis severity (<50% or ≥50%) or CT-FFR positivity. Conclusion: Both anatomic CCTA findings and CT-FFR demonstrated a more complex pattern of CAD in participants with versus without DM. Rates of treatment reclassification were similar regardless of the presence of DM, and DM was not an adverse prognostic indicator when adjusted for diameter stenosis and CT-FFR.Clinical trial registration no. NCT 02499679Keywords: Fractional Flow Reserve, CT Angiography, Diabetes Mellitus, Coronary Artery Disease Supplemental material is available for this article. See also the commentary by Ghoshhajra in this issue.© RSNA, 2023.

Coronary Computed Tomographic Angiography With Fractional Flow Reserve in Patients With Type 2 Myocardial Infarction.

BACKGROUND: Type 2 myocardial infarction (T2MI) related to a supply/demand imbalance of coronary blood flow is common and associated with poor prognosis. Coronary artery disease (CAD) may predispose some individuals to T2MI and contribute to its high rate of recurrent cardiovascular events. Little is known about the presence and extent of CAD in this population. OBJECTIVES: The goal of this study was to evaluate the presence and characteristics of CAD among patients with T2MI. METHODS: In this prospective study, consecutive eligible individuals with Fourth Universal Definition of Myocardial Infarction criteria for T2MI were enrolled. Participants underwent coronary computed tomography angiography (CTA), fractional flow reserve derived with coronary CTA (FFRCT), and plaque volume analyses. RESULTS: Among 50 participants, 25 (50%) were female, and the mean age was 68.0 ± 11.4 years. Atherosclerotic risk factors were common. Coronary CTA revealed coronary plaque in 46 participants (92%). A moderate or greater stenosis (≥50%) was identified in 42% of participants, and obstructive disease (≥50% left main stenosis or ≥70% stenosis in any other epicardial coronary artery) was present in 26%. Prevalence of obstructive CAD did not differ according to T2MI cause (P = 0.54). A hemodynamically significant focal stenosis identified by FFRCT was present in 13 participants (26%). Among participants with a stenosis ≥50% (n = 21), FFRCT excluded lesion-specific hemodynamically significant stenosis in 8 cases (38%). CONCLUSIONS: Among individuals with adjudicated T2MI, CAD was prevalent, but the majority of patients had nonobstructive CAD. Mediators of ischemia are likely multifactorial in this population. (Defining the Prevalence and Characteristics of Coronary Artery Disease Among Patients with Type 2 Myocardial Infarction using CT-FFR [DEFINE TYPE 2 MI]; NCT04864119).

Prognostic Value of Coronary CT Angiography-derived Fractional Flow Reserve on 3-year Outcomes in Patients with Stable Angina.

Background The prognostic value of coronary CT angiography (CTA)-derived fractional flow reserve (FFR) beyond 1-year outcomes and in patients with high levels of coronary artery calcium (CAC) is uncertain. Purpose To assess the prognostic value of coronary CTA-derived FFR test results on 3-year clinical outcomes in patients with coronary stenosis and among a subgroup of patients with high levels of CAC. Materials and Methods This study represents a 3-year follow-up of patients with new-onset stable angina pectoris who were consecutively enrolled in the Assessing Diagnostic Value of Noninvasive CT-FFR in Coronary Care, known as ADVANCE (ClinicalTrials.gov: NCT02499679) registry, between December 2015 and October 2017 at three Danish sites. A high CAC was defined as an Agatston score of at least 400. A lesion-specific coronary CTA-derived FFR value of 2 cm with distal-to-stenosis value at or below 0.80 represented an abnormal test result. The primary end point was a composite of all-cause death and nonfatal spontaneous myocardial infarction. Event rates were estimated using the one-sample binomial model, and relative risk was compared between participants stratified by results of coronary CTA-derived FFR. Results This study included 900 participants: 523 participants with normal results (mean age, 64 years ± 9.6 [SD]; 318 male participants) and 377 with abnormal results from coronary CTA-derived FFR (mean age, 65 years ± 9.6; 264 male participants). The primary end point occurred in 11 of 523 (2.1%) and 25 of 377 (6.6%) participants with normal and abnormal coronary CTA-derived FFR results, respectively (relative risk, 3.1; 95% CI: 1.6, 6.3; P < .001). In participants with high CAC, the primary end point occurred in four of 182 (2.2%) and 19 of 212 (9.0%) participants with normal and abnormal coronary CTA-derived FFR results, respectively (relative risk, 4.1; 95% CI: 1.4, 11.8; P = .001). Conclusion In individuals with stable angina, a normal coronary CTA-derived FFR test result identified participants with a low 3-year risk of all-cause death or nonfatal spontaneous myocardial infarction, both in the overall cohort and in participants with high CAC scores. Clinical trial registration no. NCT02499679 Published under a CC BY 4.0 license. Supplemental material is available for this article. See also the editorial by Sinitsyn in this issue.

Comparison of an Initial Risk-Based Testing Strategy vs Usual Testing in Stable Symptomatic Patients With Suspected Coronary Artery Disease: The PRECISE Randomized Clinical Trial.

Importance: Trials showing equivalent or better outcomes with initial evaluation using coronary computed tomography angiography (cCTA) compared with stress testing in patients with stable chest pain have informed guidelines but raise questions about overtesting and excess catheterization. Objective: To test a modified initial cCTA strategy designed to improve clinical efficiency vs usual testing (UT). Design, Setting, and Participants: This was a pragmatic randomized clinical trial enrolling participants from December 3, 2018, to May 18, 2021, with a median of 11.8 months of follow-up. Patients from 65 North American and European sites with stable symptoms of suspected coronary artery disease (CAD) and no prior testing were randomly assigned 1:1 to precision strategy (PS) or UT. Interventions: PS incorporated the Prospective Multicenter Imaging Study for the Evaluation of Chest Pain (PROMISE) minimal risk score to quantitatively select minimal-risk participants for deferred testing, assigning all others to cCTA with selective CT-derived fractional flow reserve (FFR-CT). UT included site-selected stress testing or catheterization. Site clinicians determined subsequent care. Main Outcomes and Measures: Outcomes were clinical efficiency (invasive catheterization without obstructive CAD) and safety (death or nonfatal myocardial infarction [MI]) combined into a composite primary end point. Secondary end points included safety components of the primary outcome and medication use. Results: A total of 2103 participants (mean [SD] age, 58.4 [11.5] years; 1056 male [50.2%]) were included in the study, and 422 [20.1%] were classified as minimal risk. The primary end point occurred in 44 of 1057 participants (4.2%) in the PS group and in 118 of 1046 participants (11.3%) in the UT group (hazard ratio [HR], 0.35; 95% CI, 0.25-0.50). Clinical efficiency was higher with PS, with lower rates of catheterization without obstructive disease (27 [2.6%]) vs UT participants (107 [10.2%]; HR, 0.24; 95% CI, 0.16-0.36). The safety composite of death/MI was similar (HR, 1.52; 95% CI, 0.73-3.15). Death occurred in 5 individuals (0.5%) in the PS group vs 7 (0.7%) in the UT group (HR, 0.71; 95% CI, 0.23-2.23), and nonfatal MI occurred in 13 individuals (1.2%) in the PS group vs 5 (0.5%) in the UT group (HR, 2.65; 95% CI, 0.96-7.36). Use of lipid-lowering (450 of 900 [50.0%] vs 365 of 873 [41.8%]) and antiplatelet (321 of 900 [35.7%] vs 237 of 873 [27.1%]) medications at 1 year was higher in the PS group compared with the UT group (both P < .001). Conclusions and Relevance: An initial diagnostic approach to stable chest pain starting with quantitative risk stratification and deferred testing for minimal-risk patients and cCTA with selective FFR-CT in all others increased clinical efficiency relative to UT at 1 year. Additional randomized clinical trials are needed to verify these findings, including safety. Trial Registration: ClinicalTrials.gov Identifier: NCT03702244.

Deferred Testing in Stable Outpatients With Suspected Coronary Artery Disease: A Prespecified Secondary Analysis of the PRECISE Randomized Clinical Trial.

Importance: Guidelines recommend deferral of testing for symptomatic people with suspected coronary artery disease (CAD) and low pretest probability. To our knowledge, no randomized trial has prospectively evaluated such a strategy. Objective: To assess process of care and health outcomes in people identified as minimal risk for CAD when testing is deferred. Design, Setting, and Participants: This randomized, pragmatic effectiveness trial included prespecified subgroup analysis of the PRECISE trial at 65 North American and European sites. Participants identified as minimal risk by the validated PROMISE minimal risk score (PMRS) were included. Intervention: Randomization to a precision strategy using the PMRS to assign those with minimal risk to deferred testing and others to coronary computed tomography angiography with selective computed tomography-derived fractional flow reserve, or to usual testing (stress testing or catheterization with PMRS masked). Randomization was stratified by PMRS risk. Main Outcome: Composite of all-cause death, nonfatal myocardial infarction (MI), or catheterization without obstructive CAD through 12 months. Results: Among 2103 participants, 422 were identified as minimal risk (20%) and randomized to deferred testing (n = 214) or usual testing (n = 208). Mean age (SD) was 46 (8.6) years; 304 were women (72%). During follow-up, 138 of those randomized to deferred testing never had testing (64%), whereas 76 had a downstream test (36%) (at median [IQR] 48 [15-78] days) for worsening (30%), uncontrolled (10%), or new symptoms (6%), or changing clinician preference (19%) or participant preference (10%). Results were normal for 96% of these tests. The primary end point occurred in 2 deferred testing (0.9%) and 13 usual testing participants (6.3%) (hazard ratio, 0.15; 95% CI, 0.03-0.66; P = .01). No death or MI was observed in the deferred testing participants, while 1 noncardiovascular death and 1 MI occurred in the usual testing group. Two participants (0.9%) had catheterizations without obstructive CAD in the deferred testing group and 12 (5.8%) with usual testing (P = .02). At baseline, 70% of participants had frequent angina and there was similar reduction of frequent angina to less than 20% at 12 months in both groups. Conclusion and Relevance: In symptomatic participants with suspected CAD, identification of minimal risk by the PMRS guided a strategy of initially deferred testing. The strategy was safe with no observed adverse outcome events, fewer catheterizations without obstructive CAD, and similar symptom relief compared with usual testing. Trial Registration: ClinicalTrials.gov Identifier: NCT03702244.

Coronary Volume to Left Ventricular Mass Ratio in Patients With Hypertension.

The coronary vascular volume to left ventricular mass (V/M) ratio assessed by coronary computed tomography angiography (CCTA) is a promising new parameter to investigate the relation of coronary vasculature to the myocardium supplied. It is hypothesized that hypertension decreases the ratio between coronary volume and myocardial mass by way of myocardial hypertrophy, which could explain the detected abnormal myocardial perfusion reserve reported in patients with hypertension. Individuals enrolled in the multicenter ADVANCE (Assessing Diagnostic Value of Noninvasive FFRCT in Coronary Care) registry who underwent clinically indicated CCTA for analysis of suspected coronary artery disease with known hypertension status were included in current analysis. The V/M ratio was calculated from CCTA by segmenting the coronary artery luminal volume and left ventricular myocardial mass. In total, 2,378 subjects were included in this study, of whom 1,346 (56%) had hypertension. Left ventricular myocardial mass and coronary volume were higher in subjects with hypertension than normotensive patients (122.7 ± 32.8 g vs 120.0 ± 30.5 g, p = 0.039, and 3,105.0 ± 992.0 mm3 vs 2,965.6 ± 943.7 mm3, p <0.001, respectively). Subsequently, the V/M ratio was higher in patients with hypertension than those without (26.0 ± 7.6 mm3/g vs 25.3 ± 7.3 mm3/g, p = 0.024). After correcting for potential confounding factors, the coronary volume and ventricular mass remained higher in patients with hypertension (least square) mean difference estimate: 196.3 (95% confidence intervals [CI] 119.9 to 272.7) mm3, p <0.001, and 5.60 (95% CI 3.42 to 7.78) g, p <0.001, respectively), but the V/M ratio was not significantly different (least square mean difference estimate: 0.48 (95% CI -0.12 to 1.08) mm3/g, p = 0.116). In conclusion, our findings do not support the hypothesis that the abnormal perfusion reserve would be caused by reduced V/M ratio in patients with hypertension.

Coronary CT-based FFR in patients with acute myocardial infarction might predict follow-up invasive FFR: The XPECT-MI study.

BACKGROUND: We aimed to evaluate whether invasive fractional flow reserve (FFRi) of non-infarction related (non-IRA) lesions changes over time in ST-elevation myocardial infarction (STEMI) patients. Moreover, we assessed the diagnostic performance of coronary CT angiography-derived FFR(FFRCT) following the index event in predicting follow-up FFRi. METHODS: We prospectively enrolled 38 STEMI patients (mean age 61.6 â€‹± â€‹9 years, 23.1% female) who underwent non-IRA baseline and follow-up FFRi measurements and a baseline FFRCT (within ≤10 days after STEMI). Follow-up FFRi was performed at 45-60 days (FFRi and FFRCT value of ≤0.8 was considered positive). RESULTS: FFRi values showed significant difference between baseline and follow-up (median and interquartile range (IQR) 0.85 [0.78-0.92] vs. 0.81 [0.73-0.90] p â€‹= â€‹0.04, respectively). Median FFRCT was 0.81 [0.68-0.93]. In total, 20 lesions were positive on FFRCT. A stronger correlation and smaller bias were found between FFRCT and follow-up FFRi (ρ â€‹= â€‹0.86,p â€‹< â€‹0.001,bias:0.01) as compared with baseline FFRi (ρ â€‹= â€‹0.68, p â€‹< â€‹0.001,bias:0.04). Comparing follow-up FFRi and FFRCT, no false negatives but two false positive cases were found. The overall accuracy was 94.7%, with sensitivity and specificity of 100.0% and 90.0% for identifying lesions ≤0.8 on FFRi. Accuracy, sensitivity, and specificity were 81.5%, 93.3%, and 73.9%, respectively, for identifying significant lesions on baseline FFRi using index FFRCT. CONCLUSION: FFRCT in STEMI patients close to the index event could identify hemodynamically relevant non-IRA lesions with higher accuracy than FFRi measured at the index PCI, using follow-up FFRi as the reference standard. Early FFRCT in STEMI patients might represent a new application for cardiac CT to improve the identification of patients who benefit most from staged non-IRA revascularization.

Influence of Obesity on Coronary Artery Disease and Clinical Outcomes in the ADVANCE Registry.

BACKGROUND: The relationship between body size and cardiovascular events is complex. This study utilized the ADVANCE (Assessing Diagnostic Value of Noninvasive FFRCT in Coronary Care) Registry to investigate the association between body mass index (BMI), coronary artery disease (CAD), and clinical outcomes. METHODS: The ADVANCE registry enrolled patients undergoing evaluation for clinically suspected CAD who had >30% stenosis on cardiac computed tomography angiography. Patients were stratified by BMI: normal <25 kg/m2, overweight 25-29.9 kg/m2, and obese ≥30 kg/m2. Baseline characteristics, cardiac computed tomography angiography and computed tomography fractional flow reserve (FFRCT), were compared across BMI groups. Adjusted Cox proportional hazards models assessed the association between BMI and outcomes. RESULTS: Among 5014 patients, 2166 (43.2%) had a normal BMI, 1883 (37.6%) were overweight, and 965 (19.2%) were obese. Patients with obesity were younger and more likely to have comorbidities, including diabetes and hypertension (all P<0.001), but were less likely to have obstructive coronary stenosis (65.2% obese, 72.2% overweight, and 73.2% normal BMI; P<0.001). However, the rate of hemodynamic significance, as indicated by a positive FFRCT, was similar across BMI categories (63.4% obese, 66.1% overweight, and 67.8% normal BMI; P=0.07). Additionally, patients with obesity had a lower coronary volume-to-myocardial mass ratio compared with patients who were overweight or had normal BMI (obese BMI, 23.7; overweight BMI, 24.8; and normal BMI, 26.3; P<0.001). After adjustment, the risk of major adverse cardiovascular events was similar regardless of BMI (all P>0.05). CONCLUSIONS: Patients with obesity in the ADVANCE registry were less likely to have anatomically obstructive CAD by cardiac computed tomography angiography but had a similar degree of physiologically significant CAD by FFRCT and similar rates of adverse events. An exclusively anatomic assessment of CAD in patients with obesity may underestimate the burden of physiologically significant disease that is potentially due to a significantly lower volume-to-myocardial mass ratio.

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.