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Background: Within the SCOT-HEART (Scottish COmputed Tomography of the HEART Trial) trial of patients with stable chest pain, the use of coronary computed tomography angiography (CTA) reduced the rate of death from coronary heart disease or nonfatal myocardial infarction (primary endpoint)., Objectives: This study sought to assess the consistency and mechanisms of the 5-year reduction in this endpoint., Methods: In this open-label trial, 4,146 participants were randomized to standard care alone or standard care plus coronary CTA. This study explored the primary endpoint by symptoms, diagnosis, coronary revascularizations, and preventative therapies., Results: Event reductions were consistent across symptom and risk categories (p = NS for interactions). In patients who were not diagnosed with angina due to coronary heart disease, coronary CTA was associated with a lower primary endpoint incidence rate (0.23; 95% confidence interval [CI]: 0.13 to 0.35 vs. 0.59; 95% CI: 0.42 to 0.80 per 100 patient-years; p < 0.001). In those who had undergone coronary CTA, rates of coronary revascularization were higher in the first year (hazard ratio [HR]: 1.21; 95% CI: 1.01 to 1.46; p = 0.042) but lower beyond 1 year (HR: 0.59; 95% CI: 0.38 to 0.90; p = 0.015). Patients assigned to coronary CTA had higher rates of preventative therapies throughout follow-up (p < 0.001 for all), with rates highest in those with CT-defined coronary artery disease. Modeling studies demonstrated the plausibility of the observed effect size., Conclusions: The beneficial effect of coronary CTA on outcomes is consistent across subgroups with plausible underlying mechanisms. Coronary CTA improves coronary heart disease outcomes by enabling better targeting of preventative treatments to those with coronary artery disease. (Scottish COmputed Tomography of the HEART Trial [SCOT-HEART]; NCT01149590)., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: To assess whether gradations of left ventricular (LV) ejection fraction (LVEF) and volumes measured with coronary computed tomography (CT) would augment risk stratification and discrimination for incident mortality., Materials and Methods: This study was approved by the institutional review board, and informed consent was obtained when required. Subjects without known coronary artery disease (CAD) who underwent cardiac CT angiography with quantitative LV measurements were categorized according to LVEF (≥ 55%, 45%-54.9%, 35%-44.9%, or <35%). LV end-systolic volume (LVESV) and LV end-diastolic volume (LVEDV) were classified as normal (≥ 90 mL) or abnormal (≥ 200 mL). CAD extent and severity was categorized as none, nonobstructive, obstructive (≥ 50%), one-vessel, two-vessel, and three-vessel or left main disease. LVEF and volumes were assessed for risk prediction and discrimination of future mortality by using Cox hazards model and receiver operating characteristic curve analysis, respectively., Results: During a follow-up of 2.0 years ± 0.9, 7758 patients (mean age, 58.5 years ± 13.0; 4220 male patients [54.4%]) were studied. At multivariable analysis, worsening LVEF was independently associated with mortality for moderately (hazard ratio = 3.14, P < .001) and severely (hazard ratio = 5.19, P < .001) abnormal ejection fraction. LVEF demonstrated improved discrimination for mortality (Az = 0.816) when compared with CAD risk factors alone (Az = 0.781) or CAD risk factors plus extent and severity. At multivariable analysis of a subgroup of 3706 individuals, abnormal LVEDV (hazard ratio = 4.02) and LVESV (hazard ratio = 6.46) helped predict mortality (P < .001). Similarly, LVESV and LVEDV demonstrated improved discrimination when compared with CAD risk factors or CAD extent and severity (P < .05)., Conclusion: LV dysfunction and volumes measured with cardiac CT angiography augment risk prediction and discrimination for future mortality., (© RSNA, 2014.)

Background: Coronary CT angiography (CTA) has emerged as an effective noninvasive method for direct visualization of the coronary arteries, with high diagnostic performance compared with invasive coronary angiography (ICA). However, coronary CTA is prone to artifacts, including coronary motion, which may reduce its diagnostic performance. Intracycle motion compensation algorithms (MCAs) from a combination of software and hardware techniques now allow for correction of coronary motion, but the diagnostic performance of MCAs compared with traditional coronary CTA reconstruction methods remains unexplored., Methods: ViCTORY (Validation of an Intracycle CT Motion CORrection Algorithm for Diagnostic AccuracY) is a prospective international multicenter trial of 218 patients which is designed to evaluate the performance of MCAs for the diagnosis of anatomically obstructive coronary artery disease (CAD) compared with an ICA reference standard, on a per-patient, per-vessel, and per-segment basis. Patients enrolled into ViCTORY will undergo investigational coronary CTA and clinically indicated ICA and will not receive heart rate-lowering medications before coronary CTA. Coronary CTA images will be reconstructed by conventional standard methods as well as by MCAs. Blinded core laboratory interpretation will be performed for coronary CTA and ICA in an intent-to-diagnose fashion., Results: The primary end point of ViCTORY is the per-patient diagnostic accuracy of MCAs for the diagnosis of anatomically obstructive CAD compared with ICA. Secondary end points will include other per-patient, per-vessel, and per-segment diagnostic performance characteristics, including accuracy, sensitivity, specificity, positive predictive value, and negative predictive value. Other key secondary end points will include diagnostic interpretability, image quality, the upper heart rate threshold of utility of MCAs, and the additive value of MCAs to traditionally reconstructed coronary CTA., Conclusion: ViCTORY will determine whether MCAs improve the diagnosis of obstructive CAD in patients undergoing coronary CTA who are not receiving heart rate-lowering medications., (Copyright © 2013. Published by Elsevier Inc.)

Objective: To determine whether evaluation of resting myocardial CT perfusion (CTP) from coronary CT angiography (CTA) datasets in patients presenting with chest pain (CP) to the emergency department (ED), might have added value to coronary CTA., Design, Setting: 76 Patients (age 54.9 y±13; 32 (42%) women) presenting with CP to the ED underwent coronary 64-slice CTA. Myocardial perfusion defects were evaluated for CTP (American Heart Association 17-segment model) and compared with rest sestamibi single-photon emission CT myocardial perfusion imaging (SPECT-MPI). CTA was assessed for >50% stenosis per vessel., Results: CTP demonstrated a sensitivity of 92% and 89%, specificity of 95% and 99%, positive predictive value (PPV) of 80% and 82% and negative predictive value (NPV) of 98% and 99% for each patient and for each segment, respectively. CTA showed an accuracy of 92%, sensitivity of 70.4%, specificity of 95.5%, PPV 67.8%, and NPV of 95% compared with SPECT-MPI. When CTP findings were added to CTA the PPV improved from 67% to 90.1%., Conclusions: In patients presenting to the ED with CP, the evaluation of rest myocardial CTP demonstrates high diagnostic performance as compared with SPECT-MPI. Addition of CTP to CTA improves the accuracy of CTA, primarily by reducing rates of false-positive CTA.

Objective: We determined the effect of reduced 80-kVp tube voltage on the radiation dose and image quality of coronary CT angiography (CTA) in patients with a normal body mass index (BMI)., Subjects and Methods: A prospective, multicenter, multivendor trial was performed of 208 consecutive patients with a normal BMI (< 25 kg/m(2)) who had been referred for coronary CTA and did not have a history of coronary revascularization. Patients were randomized to 80-kVp imaging (n = 103) or 100-kVp imaging (n = 105). Three blinded readers graded interpretability and image quality. Study signal, noise, and contrast were also compared., Results: Imaging with 80 kVp instead of 100 kVp was associated with 47% lower median radiation dose (median dose-length product, 62.0 mGy · cm [interquartile range, 54.0-123.3 mGy · cm] vs 117.0 mGy · cm [110.0-225.9 mGy · cm], respectively; 0.9 mSv [0.8-1.7 mSv] vs 1.6 mSv [1.4-3.2 mSv]; p < 0.001 for each) with no significant difference in interpretability (99% vs 99%; p = 0.99) or image quality (median score, 4.0 [interquartile range, 3.6-4.0] vs 4.0 [interquartile range, 3.8-4.0]; p = 0.20). Studies obtained using 80 kVp were associated with 27% increased signal (mean ± SD, 756 ± 157 vs 594 ± 105 HU; p < 0.001), 25% higher contrast (890 ± 156 vs 709 ± 108 HU; p < 0.001), and 50% greater noise (55 ± 15 vs 37 ± 12 HU; p < 0.001) with resultant 15% and 16% decreases in signal-to-noise (mean ± SD, 15 ± 5 vs 17 ± 5; p < 0.001) and contrast-to-noise (mean ± SD, 17 ± 6 vs 21 ± 5; p < 0.001) ratios, respectively., Conclusion: Coronary CTA using 80 kVp instead of 100 kVp was associated with a nearly 50% reduction in radiation dose with no significant difference in interpretability and noninferior image quality despite lower signal-to-noise and contrast-to-noise ratios. The use of 80-kVp tube voltage should be considered in dose-reduction strategies for coronary CTA of individuals with a normal BMI.

Objective: Tube voltage reduction has been shown to be an effective method to reduce radiation dose in nonobese patients undergoing coronary CT angiography. To date, the impact of reduced tube voltage on objective measures of diagnostic accuracy, as defined by quantitative coronary angiography (QCA), has not been established. The purpose of this article was to investigate the impact of tube voltage reduction on the diagnostic performance of coronary CTA compared with QCA., Subjects and Methods: We performed a prospective randomized trial evaluating 50 consecutive patients referred for catheter angiography with a body mass index (BMI) ≤ 35 kg/m². Patients were randomly assigned to reduced (n = 24) or standard tube voltage (n = 26). Reduced tube voltage was defined as 80 or 100 kVp for individuals with BMI < 25 kg/m² or 25-35 kg/m², respectively; whereas standard tube voltage was defined as 100 or 120 kVp for individuals with BMI < 25 kg/m² or 25-35 kg/m², respectively. Tube current was fixed by study protocol as 600 mA (BMI < 30 kg/m²) or 650 mA (BMI ≥ 30 kg/m²). Coronary CTA examinations were interpreted by two blinded experienced readers with a third reader providing consensus. QCA was performed by an independent experienced core laboratory blinded to coronary CTA findings. Coronary artery segments were graded for stenosis as < 50%, 50-69%, and ≥ 70% by coronary CTA and as percentage stenosis by QCA. In an intention-to-diagnose fashion, all segments were included for final analysis, with nonevaluable segments by coronary CTA graded as obstructive. Signal and noise; contrast (mean signal-signal in left ventricular myocardium); and signal-to-noise ratio (SNR) and contrast-to-noise (CNR) ratio were compared., Results: Mean age of the study cohort was 60.2 years; 78% were men. Prospective ECG gating was used in all patients, and no differences existed in scan length between groups (p = 0.19). Standard versus reduced tube voltage was associated with a reduction in effective radiation dose (2.6 ± 0.4 vs 1.3 ± 0.5 mSv, p < 0.001). The patient prevalence of luminal stenosis ≥ 50% was 56% (28/50). For detection of ≥ 50% stenosis in the standard versus reduced kVp groups, there were no differences in per-segment sensitivity (87% vs 84%, p = 0.73), specificity (92% vs 93%, p = 0.81), or accuracy (92% vs 91%, p = 0.70). No differences were noted for reduced versus standard tube current for SNR (13 ± 4 vs 13 ± 3, p = 0.59), CNR (10 ± 3 vs 10 ± 2, p = 0.99), or graded (0-4) image quality score (3.4 ± 0.8 vs 3.5 ± 0.6, p = 0.19)., Conclusion: Compared with standard tube voltage, coronary CTA using reduced tube voltage results in lower effective radiation dose with comparable diagnostic performance.

Objective: The objective of our study was to assess the impact of Adaptive Statistical Iterative Reconstruction (ASIR) on radiation dose and study quality for coronary CT angiography (CTA)., Subjects and Methods: We prospectively evaluated 574 consecutive patients undergoing coronary CTA at three centers. Comparisons were performed between consecutive groups initially using filtered back projection (FBP) (n = 331) and subsequently ASIR (n = 243) with regard to patient and scan characteristics, radiation dose, and diagnostic study quality., Results: There was no difference between groups in the use of prospective gating, tube voltage, or scan length. The examinations performed using ASIR had a lower median tube current than those obtained using FBP (median [interquartile range], 450 mA [350-600] vs 650 mA [531-750], respectively; p < 0.001). There was a 44% reduction in the median radiation dose between the FBP and ASIR cohorts (4.1 mSv [2.3-5.2] vs 2.3 mSv [1.9-3.5]; p < 0.001). After adjustment for scan settings, ASIR was associated with a 27% reduction in radiation dose compared with FBP (95% CI, 21-32%; p < 0.001). Despite the reduced current, ASIR was not associated with a difference in adjusted signal, noise, or signal-to-noise ratio (p = not significant). No differences existed between FBP and ASIR for interpretability per coronary artery (98.5% vs 99.3%, respectively; p = 0.12) or per patient (96.1% vs 97.1%, p = 0.65). CONCLUSION. ASIR enabled reduced tube current and lower radiation dose in comparison with FBP, with preserved signal, noise, and study interpretability, in a large multicenter cohort. ASIR represents a new technique to reduce radiation dose in coronary CTA studies.

Objective: The purpose of our study was to determine the effect of Adaptive Statistical Iterative Reconstruction (ASIR) on cardiac CT angiography (CTA) signal, noise, and image quality., Materials and Methods: We evaluated 62 consecutive patients at three sites who underwent clinically indicated cardiac CTA using an ASIR-capable 64-MDCT scanner and a low-dose cardiac CTA technique. Studies were reconstructed using filtered back projection (FBP), ASIR-FBP composites using 20-80% ASIR, and 100% ASIR. The signal and noise were measured in the aortic root and each of the four coronary arteries. Two blinded readers graded image quality on a 5-point Likert scale and determined the proportion of interpretable segments. All segments were included for analysis regardless of size., Results: In comparison with FBP (0% ASIR), the use of 20%, 40%, 60%, 80%, and 100% ASIR resulted in reduced image noise between groups (-7%, -17%, -26%, -35%, and -43%, respectively; p < 0.001) without difference in signal (p = 0.60). There were significant differences between groups (0%, 20%, 40%, 60%, 80%, and 100% ASIR) in the Likert scores (1.5, 2.1, 3.7, 3.8, 2.0, and 1.1, respectively; p < 0.001) and proportion of interpretable segments (88.7%, 89.3%, 90.5%, 90.4%, 88.0%, and 87.3%, respectively; p < 0.001). Reconstruction using 40% and 60% ASIR had the highest Likert scores and largest proportion of interpretable segments. In comparison with FBP, each was associated with higher Likert scores and increased interpretable segments (p < 0.001 for all)., Conclusion: ASIR resulted in noise reduction and significantly impacted image quality. When using a low tube current technique, cardiac CTA reconstruction using 40% or 60% ASIR significantly improved image quality and the proportion of interpretable segments compared with FBP reconstruction.

Aims Anatomic series commonly report the extent and severity of coronary artery disease (CAD), regardless of location. The aim of this study was to evaluate differences in atherosclerotic plaque burden and composition across the major epicardial coronary arteries. Methods and results A total of 1271 patients (age 60 ± 9 years; 57% men) with suspected CAD prospectively underwent coronary computed tomography angiography (CCTA). Atherosclerotic plaque volume was quantified with categorization by composition (necrotic core, fibrofatty, fibrous, and calcified) based on Hounsfield Unit density. Per-vessel measures were compared using generalized estimating equation models. On CCTA, total plaque volume was lowest in the LCx (10.0 ± 29.4 mm3), followed by the RCA (32.8 ± 82.7 mm3; P  < 0.001), and LAD (58.6 ± 83.3 mm3; P  < 0.001), even when correcting for vessel length or volume. The prevalence of ≥2 high-risk plaque features, such as positive remodelling or spotty calcification, occurred less in the LCx (3.8%) when compared with the LAD (21.4%) or RCA (10.9%, P  < 0.001). In the LCx, the most stenotic lesion was categorized as largely calcified more often than in the RCA and LAD (55.3% vs. 39.4% vs. 32.7%; P  < 0.001). Median diameter stenosis was also lowest in the LCx (16.2%) and highest in the LAD (21.3%; P  < 0.001) and located more distal along the LCx when compared with the RCA and LAD (P  < 0.001). Conclusion Atherosclerotic plaque, irrespective of vessel volume, varied across the epicardial coronary arteries; with a significantly lower burden and different compositions in the LCx when compared with the LAD and RCA. These volumetric and compositional findings support a diverse milieu for atherosclerotic plaque development and may contribute to a varied acute coronary risk between the major epicardial coronary arteries. [ABSTRACT FROM AUTHOR]

Background. In the United States, functional stress testing is the primary imaging modality for patients with stable symptoms suspected to represent coronary artery disease (CAD). Coronary computed tomography angiography (CTA) is excellent at identifying anatomic coronary artery disease (CAD). The application of computational fluid dynamics to coronary CTA allows fractional flow reserve (FFR) to be calculated noninvasively (FFRCT). The relationship of noninvasive stress testing to coronary CTA and FFRCT in real-world clinical practice has not been studied. Methods. We evaluated 206 consecutive patients at Loyola University Chicago with suspected CAD who underwent noninvasive stress testing followed by coronary CTA and FFRCT when indicated. Patients were categorized by stress test results (positive, negative, indeterminate, and equivocal). Duke treadmill score (DTS), METS, exercise duration, and chest pain with exercise were analyzed. Lesions ≥ 50 % stenosis were considered positive by coronary CTA. FF R CT < 0.80 was considered diagnostic of ischemia. Results. Two hundred and six patients had paired noninvasive stress test and coronary CTA/FFRCT results. The median time from stress test to coronary CTA was 49 days. Average patient age was 60.3 years, and 42% were male. Of the 206 stress tests, 75% were exercise (70% echocardiographic, 26% nuclear, and 4% EKG). There were no associations of stress test results with CAD > 50 % or FF R CT < 0.80 (p = 0.927 and p = 0.910 , respectively). Of those with a positive stress test, only 30% (3/10) had CAD > 50 % and only 50% (5/10) had FF R CT < 0.80. Chest pain with exercise did not correlate with CAD > 50 % or FF R CT < 0.80 (p = 0.66 and p = 0.12 , respectively). There were no significant correlations between METS, DTS, or exercise duration and FFRCT (r = 0.093 , p = 0.274 ; r = 0.012 , p = 0.883 ; and r = 0.034 , p = 0.680 ; respectively). Conclusion. Noninvasive stress testing, functional capacity, chest pain with exercise, and DTS are not associated with anatomic or functional CAD using a diagnostic strategy of coronary CTA and FFRCT. [ABSTRACT FROM AUTHOR]

Aims Although there is increasing evidence supporting coronary atherosclerosis evaluation by coronary computed tomography angiography (CCTA), no data are available on age and sex differences for quantitative plaque features. The aim of this study was to investigate sex and age differences in both qualitative and quantitative atherosclerotic features from CCTA prior to acute coronary syndrome (ACS). Methods and results Within the ICONIC study, in which 234 patients with subsequent ACS were propensity matched 1:1 with 234 non-event controls, our current subanalysis included only the ACS cases. Both qualitative and quantitative advance plaque analysis by CCTA were performed by a core laboratory. In 129 cases, culprit lesions identified by invasive coronary angiography at the time of ACS were co-registered to baseline CCTA precursor lesions. The study population was then divided into subgroups according to sex and age (<65 vs. ≥ 65 years old) for analysis. Older patients had higher total plaque volume than younger patients. Within specific subtypes of plaque volume, however, only calcified plaque volume was higher in older patients (135.9 ± 163.7 vs. 63.8 ± 94.2 mm3, P  < 0.0001, respectively). Although no sex-related differences were recorded for calcified plaque volume, females had lower fibrous and fibrofatty plaque volume than males (Fibrofatty volume 29.6 ± 44.1 vs. 75.3 ± 98.6 mm3, P  = 0.0001, respectively). No sex-related differences in the prevalence of qualitative high-risk plaque features were found, even after separate analyses considering age were performed. Conclusion Our data underline the importance of age- and sex-related differences in coronary atherosclerosis presentation, which should be considered during CCTA-based atherosclerosis quantification. [ABSTRACT FROM AUTHOR]

Aims  This study sought to determine the prognostic value of combined functional testing using positron emission tomography (PET) perfusion imaging and anatomical testing using coronary computed tomography angiography (CCTA)-derived stenosis severity and plaque morphology in patients with suspected coronary artery disease (CAD). Methods and results  In this retrospective study, 539 patients referred for hybrid [15O]H2O PET-CT imaging because of suspected CAD were investigated. PET was used to determine myocardial blood flow (MBF), whereas CCTA images were evaluated for obstructive stenoses and high-risk plaque (HRP) morphology. Patients were followed up for the occurrence of all-cause death and non-fatal myocardial infarction (MI). During a median follow-up of 6.8 (interquartile range 4.8–7.8) years, 42 (7.8%) patients experienced events, including 23 (4.3%) deaths, and 19 (3.5%) MIs. Annualized event rates for normal vs. abnormal results of PET MBF, CCTA-derived stenosis, and HRP morphology were 0.6 vs. 2.1%, 0.4 vs. 2.1%, and 0.8 vs. 2.8%, respectively (P  < 0.001 for all). Cox regression analysis demonstrated prognostic values of PET perfusion imaging [hazard ratio (HR) 3.75 (1.84–7.63), P  < 0.001], CCTA-derived stenosis [HR 5.61 (2.36–13.34), P  < 0.001], and HRPs [HR 3.37 (1.83–6.18), P  < 0.001] for the occurrence of death or MI. However, only stenosis severity [HR 3.01 (1.06–8.54), P  = 0.039] and HRPs [HR 1.93 (1.00–3.71), P  = 0.049] remained independently associated. Conclusion  PET-derived MBF, CCTA-derived stenosis severity, and HRP morphology were univariably associated with death and MI, whereas only stenosis severity and HRP morphology provided independent prognostic value. [ABSTRACT FROM AUTHOR]

Aims High-risk plaque (HRP) and non-obstructive coronary artery disease independently predict adverse events, but their importance to future culprit lesions has not been resolved. We sought to determine in patients prior to confirmed acute coronary syndrome (ACS) the association between lesion percent diameter stenosis (%DS), and the absolute number and prevalence of HRP. The secondary objective was to examine the relative importance of non-obstructive HRP in future culprit lesions. Methods and results Within the ICONIC study, a nested case–control study of patients undergoing coronary computed tomographic angiography (coronary CT), we included ACS cases with culprit lesions confirmed by invasive coronary angiography and coregistered to baseline coronary CT. Quantitative CT was used to evaluate obstructive (≥50%) and non-obstructive (<50%) diameter stenosis, with HRP defined as ≥2 features of spotty calcification, positive remodelling, or low-attenuation plaque at baseline. A total of 234 patients with downstream ACS over 54 (interquartile range 5–525.5) days exhibited 198/898 plaques with HRP on coronary CT. While HRP was less prevalent in non-obstructive (19.7%, 161/819) than obstructive lesions (46.8%, 37/79, P  <   0.001), non-obstructive plaque comprised 81.3% (161/198) of HRP lesions overall. Among the 128 patients with identifiable culprit lesion precursors, the adjusted hazard ratio (HR) was 1.85 [95% confidence interval (CI) 1.26–2.72] for HRP, with no interaction between %DS and HRP (P  =   0.82). Compared to non-obstructive HRP lesions, obstructive lesions without HRP exhibited a non-significant HR of 1.41 (95% CI 0.61–3.25, P  =   0.42). Conclusions While HRP is more prevalent among obstructive lesions, non-obstructive HRP lesions outnumber those that are obstructive and confer risk clinically approaching that of obstructive lesions without HRP. [ABSTRACT FROM AUTHOR]

Aims The long-term prognostic value of coronary computed tomography angiography (CCTA)-identified coronary artery disease (CAD) has not been evaluated in elderly patients (≥70 years). We compared the ability of coronary CCTA to predict 5-year mortality in older vs. younger populations. Methods and results From the prospective CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter) registry, we analysed CCTA results according to age <70 years (n = 7198) vs. ≥70 years (n = 1786). The severity of CAD was classified according to: (i) maximal stenosis degree per vessel: none, non-obstructive (1–49%), or obstructive (>50%); (ii) segment involvement score (SIS): number of segments with plaque. Cox-proportional hazard models assessed the relationship between CCTA findings and time to mortality. At a mean 5.6 ± 1.1 year follow-up, CCTA-identified CAD predicted increased mortality compared with patients with a normal CCTA in both <70 years [non-obstructive hazard ratio (HR) confidence interval (CI): 1.70 (1.19–2.41); one-vessel: 1.65 (1.03–2.67); two-vessel: 2.24 (1.21–4.15); three-vessel/left main: 4.12 (2.27–7.46), P < 0.001] and ≥70 years [non-obstructive: 1.84 (1.15–2.95); one-vessel: HR (CI): 2.28 (1.37–3.81); two-vessel: 2.36 (1.33–4.19); three-vessel/left main: 2.41 (1.33–4.36), P = 0.014]. Similarly, SIS was predictive of mortality in both <70 years [SIS 1–3: 1.57 (1.10–2.24); SIS ≥4: 2.42 (1.65–3.57), P < 0.001] and ≥70 years [SIS 1–3: 1.73 (1.07–2.79); SIS ≥4: 2.45 (1.52–3.93), P < 0.001]. CCTA findings similarly predicted long-term major adverse cardiovascular outcomes (MACE) (all-cause mortality, myocardial infarction, and late revascularization) in both groups compared with patients with no CAD. Conclusion The presence and extent of CAD is a meaningful stratifier of long-term mortality and MACE in patients aged <70 years and ≥70 years old. The presence of obstructive and non-obstructive disease and the burden of atherosclerosis determined by SIS remain important predictors of prognosis in older populations. [ABSTRACT FROM AUTHOR]

Aims This study explored the coronary plaque volume change (PVC) according to the change of percent body mass index (BMI) and categorical BMI group using serial coronary computed tomography angiography (CCTA). Methods and results A total of 1568 subjects who underwent serial CCTA with available BMI at baseline (CCTA1) and follow-up (CCTA2) were included. Median inter-scan period was 3.3 (interquartile range: 2.6–4.6) years. Quantitative assessment of coronary plaque was performed at both scans. All participants were categorized into three BMI (kg/m2) groups: normal: <25.0; overweight: 25.0–29.9; and obesity: ≥30.0. During follow-up, there were no significant differences in annualized PVC according to the 5% change of BMI in all BMI groups. Among 1424 (90.8%) subjects in the same BMI group at CCTA1 and CCTA2, a significant difference in annualized (PVC) was observed among the three groups. In 144 (9.2%) subjects with the change in their BMI group at CCTA2 compared their results at CCTA1, annualized PVC was not different compared with subjects in the same BMI group during follow-up. The percent change of BMI was not significantly related to the annualized PVC after adjusting confounding factors. Male gender [odds ratio (OR): 1.38; 95% confidence interval (CI): 1.05–1.81; P  = 0.022], baseline plaque volume (OR: 1.07; 95% CI: 1.05–1.09; P  < 0.001), and baseline overweight or obesity (OR: 1.35; 95% CI: 1.04–1.77; P  = 0.027) were independently associated with coronary plaque progression. Conclusion Over the near term, longitudinal small changes in BMI were not associated with changes in coronary plaque volume although baseline BMI was. Clinical trial registration ClinicalTrials.gov NCT02803411. [ABSTRACT FROM AUTHOR]

To assess the use of downstream coronary angiography (ICA) and short-term safety of frontline coronary CT angiography (CTA) with selective CT-derived fractional flow reserve (FFRCT) testing in stable patients with typical angina pectoris. Methods and results: Between 1 January 2016 and 30 June 2016 all patients (N = 774) referred to non-emergent ICA or coronary CTA at Aarhus University Hospital on a suspicion of CAD had frontline CTA performed. Downstream testing and treatment within 3 months and adverse events ≥90 days were registered. Patients were divided into two groups according to the presence of typical angina pectoris, which according to local practice would have resulted in referral to ICA, (low-intermediate-risk, n = 593 [76%]; high-risk, n = 181 [24%]) with mean pre-test probability of CAD of 31 ± 16% and 67 ± 16%, respectively. Coronary CTA was performed in 745 (96%) patients in whom FFRCT was prescribed in 212 (28%) patients. In the high- vs. low-intermediate-risk group, ICA was cancelled in 75% vs. 91%. Coronary revascularization was performed more frequently in high-risk than in low-intermediate-risk patients, 76% vs. 52% (P = 0.03). Mean follow-up time was 157 ± 50 days. Serious clinical events occurred in four patients, but not in any patients with cancelled ICA by coronary CTA with selective FFRCT testing. Conclusion: Frontline coronary CTA with selective FFRCT testing in stable patients with typical angina pectoris in real-world practice is associated with a high rate of safe cancellation of planned ICAs. [ABSTRACT FROM AUTHOR]

Aims Fractional flow reserve (FFR) derived from coronary computed tomography (FFRCT) has high diagnostic performance in stable coronary artery disease (CAD). The diagnostic performance of FFRCT in patients with hypertension (HTN) and diabetes (DM), who are at risk of microvascular impairment, is not known. Methods and results We analysed the diagnostic performance of FFRCT, in patients (vessels) with DM (n = 16), HTN (n = 186), DM + HTN (n = 58) vs. controls (n = 107) with or with suspected CAD. Patients (vessels) were further divided according to left ventricular mass index (LVMI) tertiles. Reference standard was invasively measured FFR ≤0.80. Per-patient diagnostic accuracy (95% CI) in control patients was 71.7% (61.6-81.8) vs. 79.3 (74.0-85.0) (P = 0.12), 75.0% (47.6-92.7) (P = 0.52), and 75.9% (62.8-86.1) (P = 0.39) in patients with HTN, DM, and HTM + DM, respectively. There was no difference in discrimination of ischaemia by FFRCT between groups. On a per-vessel level, there was no significant difference in diagnostic performance or discrimination of ischaemia by FFRCT between groups. There was a decline in both per-patient and -vessel diagnostic specificity of FFRCT in the upper LVMI tertile when compared with lower tertiles; however, discrimination of ischaemia by FFRCT was unaltered across LVMI tertiles. Conclusion The diagnostic performance of FFRCT is independent of the presence of HTN and DM. FFRCT is a robust method in a broad stable CAD population, including patients at high risk for microvascular disease. [ABSTRACT FROM AUTHOR]

Aims To identify the effect of early revascularization on 5-year survival in patients with CAD diagnosed by coronary- computed tomographic angiography (CCTA). Methods and results We examined 5544 stable patients with suspected CAD undergoing CCTA who were followed a median of 5.5 years in a large international registry. Patients were categorized as having low-, intermediate-, or high-risk CAD based on CCTA findings. Two treatment groups were defined: early revascularization within 90 days of CCTA (n = 1171) and medical therapy (n = 4373). To account for the non-randomized referral to revascularization, we developed a propensity score by logistic regression. This score was incorporated into Cox proportional hazard models to calculate the effect of revascularization on all-cause mortality. Death occurred in 363 (6.6%) patients and was more frequent in medical therapy. In multivariable models, when compared with medical therapy, the mortality benefit of revascularization varied significantly over time and by CAD risk (P for interaction 0.04). In high-risk CAD, revascularization was significantly associated with lower mortality at 1 year (hazard ratio [HR] 0.22, 95% confidence interval [CI] 0.11-0.47) and 5 years (HR 0.31, 95% CI 0.18-0.54). For intermediate-risk CAD, revascularization was associated with reduced mortality at 1 year (HR 0.45, 95% CI 0.22-0.93) but not 5 years (HR 0.63, 95% CI 0.33-1.20). For low-risk CAD, there was no survival benefit at either time point. Conclusions Early revascularization was associated with reduced 1-year mortality in intermediate- and high-risk CAD detected by CCTA, but this association only persisted for 5-year mortality in high-risk CAD. [ABSTRACT FROM AUTHOR]

Background Coronary computed tomography angiography (CCTA) allows for non-invasive assessment of obstructive coronary artery disease (CAD) beyond measures of stenosis severity alone. This assessment includes atherosclerotic plaque characteristics (APCs) and calculation of fractional flow reserve (FFR) from CCTA (FFRCT). Similarly, stress imaging by myocardial perfusion scintigraphy (MPS) provides vital information. To date, the diagnostic performance of integrated CCTA assessment versus integrated MPS assessment for diagnosis of vessel-specific ischemia remains underexplored. Methods CREDENCE will enroll adult individuals with symptoms suspicious of CAD referred for non-emergent invasive coronary angiography (ICA), but without known CAD. All participants will undergo CCTA, MPS, ICA and FFR. FFR will be performed for lesions identified at the time of ICA to be ≥40 and <90 % stenosis, or those clinically indicated for evaluation. Study analyses will focus on diagnostic performance of CCTA versus MPS against invasive FFR reference standard. An integrated stenosis-APC-FFRCT metric by CCTA for vessel-specific ischemia will be developed from derivation cohort and tested against a validation cohort. Similarly, integrated metric by MPS for vessel-specific ischemia will be developed, validated and compared. An FFR value of ≤0.80 will be considered as ischemia causing. The primary endpoint will be the diagnostic accuracy of vessel territory-specific ischemia of integrated stenosis-APC-FFRCT measure by CCTA, compared with perfusion or perfusion–myocardial blood flow stress imaging testing, against invasive FFR. Discussion CREDENCE will determine the performance of integrated CCTA metric compared to integrated MPS measure for diagnosis of vessel-specific ischemia. If proven successful, this study may reduce the number of missed diagnoses and help to optimally predict ischemia-causing lesions. . [ABSTRACT FROM AUTHOR]

Purpose: To compare image interpretability and diagnostic performance of dual-energy CT coronary angiography (DE-CTCA) performed with 50% iodine load reduction versus single energy acquisitions (SE-CTCA) with full iodine load.Materials and Methods: The present prospective study involved patients with suspected coronary artery disease (CAD) clinically referred for CTCA. DE-CTCA with 50% iodine volume load was performed first, and after heart rate returned to baseline SE-CTCA was performed using full iodine volume load. The primary endpoint was to compare image interpretability between groups. DE-CTCA was performed by rapid switching between low and high tube potentials (80-140 kV) from a single source, allowing the generation of monochromatic image reconstructions ranging from 40 to 140 keV. Image quality assessment was performed using a 5-point Likert scale.Results: Thirty-six patients constituted the study population. The mean heart rate before the CT scan (DE-CTCA 57.3 ± 10.7 bpm vs. SE-CTCA 58.5 ± 11.2 bpm, p=0.29) and the mean effective radiation dose (3.5 ± 1.9 mSv vs. 3.8 ± 0.9 mSv, p=0.48) did not differ between groups. Likert image quality scores were similar between groups (DE-CTCA 4.42 ± 0.98 vs. SE-CTCA 4.43 ± 0.84, p=0.67). Signal-to-noise and contrast-to-noise ratios were significantly lower with DE-CTCA, driven by lower signal density levels at 60 keV compared to SE-CTCA. The sensitivity and specificity for the detection of stenosis >50% was indistinguishable between groups (DE-CTCA 84.4% (69.9-93.0%), 87.1% (81.6-91.2%); SE-CTCA 84.4% (69.9-93.0%), 87.1% (81.6-91.2%).Conclusions: In this pilot, prospective study, dual energy CTCA imaging with half iodine load achieved comparable interpretability than full iodine load with single energy CTCA. [ABSTRACT FROM AUTHOR]

Aims Adverse plaque characteristics (APCs) by coronary computed tomography (CT) angiography (CTA) are associated with myocardial ischaemia and future acute coronary syndromes. The overall objective was to determine whether APCs on non-invasive CTA are associated with vulnerable plaque features by invasive optical coherence tomography (OCT). Methods and results Sixty-eight coronary plaques in 45 patients were evaluated by CTA and OCT. APCs by CTA were: positive remodelling (PR), remodelling index ≥1.10; low attenuation plaque (LAP), any intraplaque voxel,30 Hounsfield units; spotty calcification (SC), intraplaque calcification ≤3 mm; and 'napkin-ring' sign, low intraplaque attenuation surrounded by a higher attenuation rim. OCT evaluated plaques for thin-cap fibroatheroma (TCFA, ≤65 mm, lipid arch .908) and macrophage infiltration. Increasing plaque vulnerability was graded by OCT as having no TCFA, TCFA without macrophage infiltration, and TCFA with macrophage infiltration .OCT lesions included those with no TCFA(n = 44), TCFA without macrophage infiltration (n = 7), and TCFA with macrophage infiltration (n = 17). Increasing plaque vulnerability grade by OCT was associated with higher diameter stenosis (43.6 vs. 40.7 vs. 57.3%, P = 0.01), and greater prevalence of PR (11 vs. 43 vs. 71%, P < 0.001), LAP (11 vs. 29 vs. 59%, P = 0.001), and SC (2 vs. 29 vs. 18%, P = 0.02), but not for napkin-ring sign (P = 0.18). In multivariable analysis, PR [odds ratio (OR) 16.9, 95% confidence interval (CI) 3.9-73.3, P < 0.001] and LAP (OR 11.2, 95% CI 2.8-44.3, P = 0.001) predicted TCFA with macrophage infiltration, whereas SC and napkin-ring sign did not. Conclusion Plaques demonstrating PR and LAP by CTA are associated with TCFA with macrophage infiltration by OCT. [ABSTRACT FROM AUTHOR]

Objectives: The goal of this study was to determine the diagnostic performance of noninvasive fractional flow reserve (FFR) derived from standard acquired coronary computed tomography angiography (CTA) datasets (FFRCT) for the diagnosis of myocardial ischemia in patients with suspected stable coronary artery disease (CAD). Background: FFR measured during invasive coronary angiography (ICA) is the gold standard for lesion-specific coronary revascularization decisions in patients with stable CAD. The potential for FFRCT to noninvasively identify ischemia in patients with suspected CAD has not been sufficiently investigated. Methods: This prospective multicenter trial included 254 patients scheduled to undergo clinically indicated ICA for suspected CAD. Coronary CTA was performed before ICA. Evaluation of stenosis (>50% lumen reduction) in coronary CTA was performed by local investigators and in ICA by an independent core laboratory. FFRCT was calculated and interpreted in a blinded fashion by an independent core laboratory. Results were compared with invasively measured FFR, with ischemia defined as FFRCT or FFR ≤0.80. Results: The area under the receiver-operating characteristic curve for FFRCT was 0.90 (95% confidence interval [CI]: 0.87 to 0.94) versus 0.81 (95% CI: 0.76 to 0.87) for coronary CTA (p = 0.0008). Per-patient sensitivity and specificity (95% CI) to identify myocardial ischemia were 86% (95% CI: 77% to 92%) and 79% (95% CI: 72% to 84%) for FFRCT versus 94% (86 to 97) and 34% (95% CI: 27% to 41%) for coronary CTA, and 64% (95% CI: 53% to 74%) and 83% (95% CI: 77% to 88%) for ICA, respectively. In patients (n = 235) with intermediate stenosis (95% CI: 30% to 70%), the diagnostic accuracy of FFRCT remained high. Conclusions: FFRCT provides high diagnostic accuracy and discrimination for the diagnosis of hemodynamically significant CAD with invasive FFR as the reference standard. When compared with anatomic testing by using coronary CTA, FFRCT led to a marked increase in specificity. (HeartFlowNXT–HeartFlow Analysis of Coronary Blood Flow Using Coronary CT Angiography [HFNXT]; NCT01757678) [Copyright &y& Elsevier]

Aims The prognostic value of coronary artery calcium (CAC) scoring is well established and has been suggested for use to exclude significant coronary artery disease (CAD) for symptomatic individuals with CAD. Contrast-enhanced coronary computed tomographic angiography (CCTA) is an alternative modality that enables direct visualization of coronary stenosis severity, extent, and distribution. Whether CCTA findings of CAD add an incremental prognostic value over CAC in symptomatic individuals has not been extensively studied. Methods and results We prospectively identified symptomatic patients with suspected but without known CAD who underwent both CAC and CCTA. Symptoms were defined by the presence of chest pain or dyspnoea, and pre-test likelihood of obstructive CAD was assessed by the method of Diamond and Forrester (D–F). CAC was measured by the method of Agatston. CCTAs were graded for obstructive CAD (>70% stenosis); and CAD plaque burden, distribution, and location. Plaque burden was determined by a segment stenosis score (SSS), which reflects the number of coronary segments with plaque, weighted for stenosis severity. Plaque distribution was established by a segment-involvement score (SIS), which reflects the number of segments with plaque irrespective of stenosis severity. Finally, a modified Duke prognostic index—accounting for stenosis severity, plaque distribution, and plaque location—was calculated. Nested Cox proportional hazard models for a composite endpoint of all-cause mortality and non-fatal myocardial infarction (D/MI) were employed to assess the incremental prognostic value of CCTA over CAC. A total of 8627 symptomatic patients (50% men, age 56 ± 12 years) followed for 25 months (interquartile range 17–40 months) comprised the study cohort. By CAC, 4860 (56%) and 713 (8.3%) patients had no evident calcium or a score of >400, respectively. By CCTA, 4294 (49.8%) and 749 (8.7%) had normal coronary arteries or obstructive CAD, respectively. At follow-up, 150 patients experienced D/MI. CAC improved discrimination beyond D–F and clinical variables (area under the receiver-operator characteristic curve 0.781 vs. 0.788, P = 0.004). When added sequentially to D–F, clinical variables, and CAC, all CCTA measures of CAD improved discrimination of patients at risk for D/MI: obstructive CAD (0.82, P < 0.001), SSS (0.81, P < 0.001), SIS (0.81, P = 0.003), and Duke CAD prognostic index (0.82, P < 0.0001). Conclusion In symptomatic patients with suspected CAD, CCTA adds incremental discriminatory power over CAC for discrimination of individuals at risk of death or MI. [ABSTRACT FROM PUBLISHER]

Purpose: The objective of this study was to assess whether sex differences exist in plaque burden and plaque subtype as assessed by coronary computed tomography angiography (CCTA). Methods: The study cohort included 937 consecutive patients who underwent CCTA between 2008 and 2010. Stenosis was quantified using the Society of Cardiovascular Computed Tomography stenosis grading scale and a total stenosis score (TSS) was generated. Plaque morphology (PM) was reported as predominantly calcified (CP), noncalcified (NCP), or mixed (MP) plaque, and CP, NCP, and MP percentages were calculated. Results: On multivariate analysis, men were significantly more likely to have plaque (65.9% of men vs. 44.6% of women, p<0.001), at least one segment with ≥50% stenosis (22.7% of men vs. 10.3% of women, p<0.001) and higher TSS (mean score=2.81 for men vs. 1.58 for women, p<0.001). Sex was the strongest predictor in all models (odds ratio [OR]=2.55, 95% confidence interval [CI] 1.78-3.67, p<0.001 for any plaque; OR=2.48, 95% CI 1.48-4.16, p<0.01 for segments with ≥50% stenosis; β=1.46, 95% CI 0.69-2.22, p<0.001 for TSS). Among patients with coronary plaque present, no significant sex differences in PM were found. Conclusions: Sex was the strongest risk factor for the presence and extent of plaque. Significant sex differences in PM did not exist. [ABSTRACT FROM AUTHOR]

The article presents a study to assess the diagnostic performance of fractional flow reserve (FFR) and computed tomography (CT) for diagnosis of coronary stenosis. It informs that the coronary computed tomographic (CT) angiography is a noninvasive anatomic test for diagnosis of coronary artery disease (CAD) or stenosis irrespective of ischemia. It further adds that the fractional flow reserve (FFR) is a physiologic measure of coronary stenosis reflecting the amount of coronary flow stenosis and an invasive procedure. It is concluded that the use of noninvasive FFR and CT among stable patients of CAD are associated with improved diagnostic accuracy.

The article provides information on the DeFACTO study which examined the diagnostic performance of fractional flow reserve (FFR) from computed tomography (CT) for the detection and exclusion of hemodynamically significant coronary artery disease (CAD) in a prospective multicenter international study. It outlines inclusion/exclusion criteria of the study participants. It also details study procedures.

Abstract: Application of quantitative myocardial CT perfusion (CTP) for the assessment of coronary artery disease may have a significant effect on patient care as the functional significance of a coronary stenosis can be evaluated through absolute measurement of the downstream myocardial perfusion (MP) both at rest and under exercise or pharmacologic stress. A main challenge of myocardial CTP is beam hardening (BH), arising from the polychromatic nature of x-rays used in CT scanning and the presence of highly attenuating contrast agent in the heart chambers during the CT acquisition. The BH effect induces significant nonuniform shifts in CT numbers which, if uncorrected, can lead to inaccurate assessment of MP. With the recent developments of dual-energy CT (DECT) scanning on clinical scanners, the BH effect on MP measurement could be reduced with the generation of monochromatic images relatively free of BH artifacts from the acquired dual-energy data. Here, we review the different techniques of acquiring dual-energy scans and generating monochromatic images, followed by discussion on the progress of developing a DECT technique with reduced radiation dose for quantitative myocardial CTP. [Copyright &y& Elsevier]

OBJECTIVE--We examined the prevalence, extent, severity, and prognosis of coronary artery disease (CAD) in individuals with and without diabetes (DM) who are similar in CAD risk factors. RESEARCH DESIGN AND METHODS--We identified 23,643 consecutive individuals without known CAD undergoing coronary computed tomography angiography. A total of 3,370 DM individuals were propensity matched in a 1-to-2 fashion to 6,740 unique non-DM individuals. CAD was defined as none, nonobstructive (1-49% stenosis), or obstructive ($50% stenosis). All-cause mortality was assessed by risk-adjusted Cox proportional hazards models. RESULTS--At a 2.2-year follow-up, 108 (3.2%) and 115 (1.7%) deaths occurred among DM and non-DM individuals, respectively. Compared with non-DM individuals, DM individuals possessed higher rates of obstructive CAD (37 vs. 27%) and lower rates of having normal arteries (28 vs. 36%) (P < 0.0001). CAD extent was higher for DM versus non-DM individuals for obstructive one-vessel disease (19 vs. 14%), two-vessel disease (9 vs. 7%), and three-vessel disease (9 vs. 5%) (P < 0.0001 for comparison), with higher per-segment stenosis in the proximal and mid-segments of every coronary artery (P < 0.001 for all). Compared with non-DM individuals with no CAD, risk of mortality for DM individuals was higher for those with no CAD (hazard ratio 3.63 [95% CI 1.67-7.91]; P = 0.001), nonobstructive CAD (5.25 [2.56-10.8]; P < 0.001), one-vessel disease (6.39 [2.98-13.7]; P < 0.0001), two-vessel disease (12.33 [5.62227.1]; P < 0.0001), and three-vessel disease (13.25 [6.15-28.6]; P < 0.0001). CONCLUSIONS--Compared with matched non-DM individuals, DM individuals possess higher prevalence, extent, and severity of CAD. At comparable levels of CAD, DM individuals experience higher risk of mortality compared with non-DM individuals. [ABSTRACT FROM AUTHOR]

Background: Coronary computed tomographic angiography (CTA) allows for noninvasive identification of anatomic coronary artery disease (CAD) severity but does not discriminate whether a stenosis causes ischemia. Computational fluid dynamic techniques applied to CTA images now permit noninvasive computation of fractional flow reserve (FFR), a measure of lesion-specific ischemia, but the diagnostic performance of computed FFR (FFRCT) as compared with measured FFR at the time of invasive coronary angiography remains unexplored. Objective: We determined the diagnostic accuracy of noninvasive FFRCT for the detection and exclusion of ischemia-causing stenoses. Methods: DeFACTO (NCT01233518) is a prospective, international, multicenter study of 238 patients designed to evaluate the diagnostic performance of FFRCT for the detection of hemodynamically significant coronary artery stenoses identified by CTA, compared with invasive FFR as a reference standard. FFR values ≤ 0.80 will be considered hemodynamically significant. Patients enrolled in the DeFACTO study will undergo CTA, invasive coronary angiography, and 3-vessel FFR in the left anterior descending artery, left circumflex artery, and right coronary artery distributions. FFRCT will be computed with acquired CTA images, without modification to CTA image acquisition protocols and without additional image acquisition. Blinded core laboratory interpretation will be performed for CTA, invasive coronary angiography, FFR, and FFRCT. Results: The primary endpoint of the DeFACTO study is the per-patient diagnostic accuracy of FFRCT for noninvasive assessment of the hemodynamic significance of CAD, compared with FFR during invasive coronary angiography as a reference standard. The secondary endpoints include additional per-patient as well as per-vessel diagnostic performance characteristics, including sensitivity, specificity, positive predictive value, and negative predictive value. Conclusion: The DeFACTO study will determine whether the addition of FFRCT to conventional CTA improves the diagnosis of hemodynamically significant CAD. [Copyright &y& Elsevier]

Background: Coronary computed tomographic angiography (CCTA) possesses high accuracy to detect coronary artery disease (CAD), although studies have reported differences in diagnostic performance. Prior trials used different numbers of interpreters, and the optimal number to detect CAD is unknown. Objective: We compared the diagnostic performance of 1, 2, 3, and 5 randomly selected interpreters for CCTA. Methods: We evaluated 50 patients randomly selected from 2 multicenter studies with both 64-detector CCTA and invasive quantitative coronary angiography (QCA). Five blinded, experienced readers independently interpreted CCTA and assessed for obstructive CAD (≥50% stenosis) and high-risk CAD (left main, proximal left anterior descending, or 3-vessel stenoses). A core laboratory performed QCA. For each patient, different random combinations of readers were selected; the accuracy of 1, 2, and 5 readers was compared with 3 readers. Results: Obstructive and high-risk CAD were observed in 20 of 50 (40%) and 6 of 50 (12%) patients, respectively. With combinations of 1, 2, 3, or 5 readers, there was a range of per-patient diagnostic performance (sensitivity, 100% each; specificity, 67%–90%; accuracy, 80%–94%; P = NS), per-segment diagnostic performance (sensitivity, 67%–83%; specificity, 87%–93%; accuracy, 87%–92%; P < .001 for 1 vs 3 and 2 vs 3 readers), and detection of high-risk CAD (sensitivity, 83%–100%; specificity, 73%–80%; accuracy, 76%–82%; P = NS). The highest diagnostic accuracy was observed with 3 readers for each comparison. Conclusion: The diagnostic performance of CCTA to detect obstructive or high-risk CAD is generally high irrespective of the number of readers. Consensus interpretation by ≥3 readers provides the highest diagnostic accuracy. [ABSTRACT FROM AUTHOR]

Although numerous strategies for radiation dose decrease in coronary computed tomographic angiography are effective, their combined impact on diagnostic performance is not known. We therefore assessed the effect of a standardized coronary computed tomographic angiographic protocol on diagnostic accuracy. We evaluated 80 consecutive patients from 3 sites with coronary computed tomographic angiography and quantitative coronary angiography. All sites initially used nonstandardized protocols; 2 sites then initiated a standardized protocol, and 1 site continued its nonstandardized protocol as a time-overlapping control. Two blinded readers interpreted coronary computed tomographic angiographic studies; a third obtained consensus. A blinded core laboratory performed quantitative coronary angiography. Each segment was graded as <50% or ≥50% diameter stenosis. Compared to those using nonstandardized protocols (n = 35), studies using standardized protocols (n = 45) had a trend to increased use of prospective gating (p = 0.09), lower voltage (p <0.01), decreased current (p <0.01), and shorter scan length (p <0.01). Median (interquartile range) radiation dose decreased from 5.7 mSv (4.0 to 10.8) to 2.0 mSv (1.3 to 3.4, p <0.001). There were no significant differences in sensitivity (100%, 20 of 20, vs 100%, 18 of 18, p = 1.0), specificity (93%, 14 of 15, vs 85%, 23 of 27, p = 0.61), or accuracy (97%, 34 of 35, vs 91%, 41 of 45, p = 0.27) by patient; sensitivity (83%, 33 of 40, vs 83%, 25 of 30, p = 0.93), specificity (92%, 86 of 93, vs 92%, 134 of 146, p = 0.85), or accuracy (89%, 119 of 133, vs 90%, 159 of 176, p = 0.80) by artery; or sensitivity (80%, 44 of 55, vs 72%, 26 of 36, p = 0.74), specificity (94%, 332 of 353, vs 94%, 499 of 531, p = 0.96), or accuracy (92%, 376 of 408, vs 93%, 525 of 567, p = 0.80) by segment. In conclusion, a standardized dose-decrease protocol for coronary computed tomographic angiography decreases radiation dose without affecting diagnostic performance. [Copyright &y& Elsevier]

The article offers information on the association between ischemic heart disease (IHD) and chronic obstructive pulmonary disease (COPD). It mentions that COPD is a major risk factor for heart disease beyond and above the traditional risk factors which include hypertension or hypercholesterolemia. It states that patients with coronary artery disease and COPD have a less favorable prognosis equated with patients with no COPD.

Objectives: In the United States, the real-world feasibility and outcome of using fractional flow reserve from coronary computed tomography angiography (FFRCT) is unknown. We sought to determine whether a strategy that combined coronary computed tomography angiography (CTA) and FFRCT could safely reduce the need for invasive coronary angiography (ICA), as compared to coronary CTA alone. Methods: The study included 387 consecutive patients with suspected CAD referred for coronary CTA with selective FFRCT and 44 control patients who underwent CTA alone. Lesions with 30–90% diameter stenoses were considered of indeterminate hemodynamic significance and underwent FFRCT. Nadir FFRCT ≤ 0.80 was positive. The rate of patients having ICA, revascularization and major adverse cardiac events were recorded. Results: Using coronary CTA and selective FFRCT, 121 patients (32%) had at least one vessel with ≥50% diameter stenosis; 67/121 (55%) patients had at least one vessel with FFRCT ≤ 0.80; 55/121 (45%) underwent ICA; and 34 were revascularized. The proportion of ICA patients undergoing revascularization was 62% (34 of 55). The number of patients with vessels with 30–50% diameter of stenosis was 90 (23%); 28/90 (31%) patients had at least one vessel with FFRCT ≤ 0.80; 8/90 (9%) underwent ICA; and five were revascularized. In our institutional practice, compared to coronary CTA alone, coronary CTA with selective FFRCT reduced the rates of ICA (45% vs. 80%) for those with obstructive CAD. Using coronary CTA with selective FFRCT, no major adverse cardiac events occurred over a mean follow-up of 440 days. Conclusion: FFRCT safely deferred ICA in patients with CAD of indeterminate hemodynamic significance. A high proportion of those who underwent ICA were revascularized. [ABSTRACT FROM AUTHOR]

Introduction: Patients with family history of premature coronary artery disease (CAD) are at risk of CAD events at younger age. Risk factor based approaches and clinical evaluation are the commonly used methods of assessment. Recently it was shown up to 50% of individual presenting with their first myocardial infarction (MI) were considered "low risk" prior to that event. MI is often a result of plaque rupture preceded by progression of subclinical atherosclerosis. Therefore, detection of subclinical atherosclerosis may help target prevention of plaque progression. In this study, we assessed the predictive value of clinical risk factor, biomarkers and Framingham Risk Score (FRS) in predicting subclinical atherosclerosis in this population. Methods: From 230 referrals,182 individuals with a family history of premature CAD, Patients between the ages of 35 to 55 were enrolled in the Early Atherosclerosis Clinic at St. Paul's Hospital, Vancouver, Canada for evaluation of risk of CAD. Premature CAD was defined as CAD events in first-degree family members (male< 55, female< 65). Patients underwent clinical and risk factor evaluations as well as Cardiac CT or Calcium Score (CS) to assess presence of subclinical/clinical atherosclerosis if indicated by the treating physician. Results: In this pilot, 67 individuals (55% male, mean age 45.8 ± 6.0 years) completed evaluation, 31(46%) had evidence of subclinical atherosclerosis on CT coronary angiography or CT calcium score with a mean segment involvement score (SIS) of 3.1 and mean CS of 128. Aside from male sex and age, other risk factors and biomarkers including diabetes mellitus, hypertension, smoking history, total cholesterol, LDL-C, HDL-C, Cholesterol/HDL-C ratio and FRS were not significantly different between those with or without subclinical atherosclerosis (Table 1). Conclusions: In young individuals with a family history of premature CAD, risk factors, biomarkers, and FRS failed to identify patients with premature, subclinical atherosclerosis in this pilot study. Detection of subclinical atherosclerosis and early implementation of treatment with the aim of stabilizing plaques and stopping progression might prove vital in reducing events in these individuals. Further studies are warranted. [ABSTRACT FROM AUTHOR]

We explored whether intracycle motion correction algorithms (MCAs) might be applicable to dual energy computed tomography coronary angiography in patients with intermediate to high likelihood of coronary artery disease. MCA reconstructions were associated with higher interpretability rates (96.7% vs. 87.9%, P < .001), image quality scores (4.12±0.9 vs. 3.76±1.0; P < .0001), and diagnostic performance [area under the curve of 0.95 (95% confidence interval [CI] 0.92–0.97) vs. 0.89 (95% CI 0.86–0.92); P < .0001] compared to conventional reconstructions. In conclusion, application of intracycle MCA reconstructions to dual energy computed tomography acquisitions was feasible and resulted in significantly higher image quality scores, interpretability, and diagnostic performance. [ABSTRACT FROM AUTHOR]

Background: Patients with obstructive coronary artery disease (CAD) are at high risk for cardiovascular disease (CVD) events. However, it remains unclear whether the high risk is due to high atherosclerotic disease burden or if presence of stenosis has independent predictive value.Objectives: The purpose of this study was to evaluate if obstructive CAD provides predictive value beyond its association with total calcified atherosclerotic plaque burden as assessed by coronary artery calcium (CAC).Methods: Among 23,759 symptomatic patients from the Western Denmark Heart Registry who underwent diagnostic computed tomography angiography (CTA), we assessed the risk of major CVD (myocardial infarction, stroke, and all-cause death) stratified by CAC burden and number of vessels with obstructive disease.Results: During a median follow-up of 4.3 years, 1,054 patients experienced a first major CVD event. The event rate increased stepwise with both higher CAC scores and number of vessels with obstructive disease (by CAC scores: 6.2 per 1,000 person-years (PY) for CAC = 0 to 42.3 per 1,000 PY for CAC >1,000; by number of vessels with obstructive disease: 6.1 per 1,000 PY for no CAD to 34.7 per 1,000 PY for 3-vessel disease). When stratified by 5 groups of CAC scores (0, 1 to 99, 100 to 399, 400 to 1,000, and >1,000), the presence of obstructive CAD was not associated with higher risk than presence of nonobstructive CAD.Conclusions: Plaque burden, not stenosis per se, is the main predictor of risk for CVD events and death. Thus, patients with a comparable calcified atherosclerosis burden generally carry a similar risk for CVD events regardless of whether they have nonobstructive or obstructive CAD. [ABSTRACT FROM AUTHOR]

Coronary computed tomography angiography (CCTA) has emerged as the preferred modality in the diagnosis of coronary artery disease, but it is limited by modest specificity. By applying principles of computational fluid dynamics, flow fraction reserve, a measure of lesion-specific ischemia that is used to guide revascularization, can be noninvasively derived from CCTA, the so-called computed tomography–derived flow fractional reserve (FFRCT). The accuracy of FFRCT in discriminating ischemia has been extensively validated, and it has been shown to improve the specificity of CCTA. Compared to other stress myocardial perfusion imaging, FFRCT has superior or comparable accuracy. Clinical studies have provided strong evidence that FFRCT has significant prognostic implications and informs clinical decisions for revascularization, serving as a gatekeeper to invasive coronary angiography. In addition, FFRCT-based tools can be used to simulate the physiological consequences of different revascularization strategies, thus providing the roadmap to achieve complete revascularization. Although challenges remain, ongoing research and randomized controlled trials are expected to address current limitations and better define its role in clinical practice. [ABSTRACT FROM AUTHOR]

Background and aims Coronary artery calcium (CAC) scoring is a predictor of future adverse clinical events, and a surrogate measure of overall coronary artery plaque burden. Coronary computed tomographic angiography (CCTA) is a contrast-enhanced method that allows for visualization of plaque as well as whether that plaque causes luminal narrowing. To date, the prognosis of individuals with CAC but without stenosis has not been reported. We explored the prevalence of CAC>0 and its prognostic utility for future mortality for patients without luminal narrowing by CCTA. Methods From 17 sites in 9 countries, we identified patients without known coronary artery disease, who underwent CAC scoring and CCTA, and were followed for >3 years. CCTA was graded for % stenosis according to a modified American Heart Association 16-segment model. We calculated hazard ratios (HR) with 95% confidence intervals (95% CI) for incident mortality and compared risk of death for patients as a function of presence or absence of CAC and presence or absence of luminal narrowing by CCTA. Results Among 6656 patients who underwent CCTA and CAC scoring, 399 patients (6.0%) had no coronary luminal narrowing but CAC>0. During a median follow-up of 5.1 years (IQR: 3.9–5.9 years), 456 deaths occurred. Compared to individuals without luminal narrowing or CAC, individuals without luminal narrowing but CAC>0 were older, more likely to be male and had higher rates of diabetes, hypertension, and dyslipidemia. Individuals without luminal narrowing but CAC experienced a 2-fold increased risk of mortality, with increasing risk of mortality with higher CAC score. Following adjustment, incident death persisted (HR, 1.8; 95% CI, 1.1–2.9, p = 0.02) among patients without luminal narrowing but with CAC>0 compared with patients whose CACS = 0. Individuals without luminal narrowing but CAC ≥100 had mortality risks similar to individuals with non-obstructive CAD (0 < stenosis<50%) by CCTA [HR 2.5 (95% CI 1.3–4.9) and 2.2 (95% CI 1.6–3.0), respectively]. Conclusions Patients without luminal narrowing but with CAC experience greater risk of 5-year mortality. Patients with CAC score ≥100 and no coronary luminal narrowing experience death rates similar to those with non-obstructive CAD. [ABSTRACT FROM AUTHOR]

Objective This study aims to determine the potential impact of introducing noninvasive fractional flow reserve based on coronary computed tomography angiography (CTA) into clinical practice, with respect to radiation dose exposure and downstream event rate. Methods We modeled a population of 1000 stable, symptomatic patients with suspected coronary artery disease, using the disease prevalence from the CONFIRM registry to estimate the pretest likelihood. Four potential clinical pathways were modeled based on the first noninvasive diagnostic test performed: (1) dobutamine echo; (2) single-photon emission computerized tomography (SPECT); (3) coronary CTA; and (4) CTA + FFRCT and leading to possible invasive coronary angiography. The posttest likelihood of testing positive/negative by each test was based on the presenting disease burden and diagnostic accuracy of each test. Results The dobutamine echo pathway resulted in the lowest radiation dose of 5.4 mSv, with 4.0 mSv from angiography and 1.4 mSv from percutaneous coronary intervention (PCI). The highest dose was with SPECT, with 26.5 mSv. The coronary computed tomography angiography (cCTA) pathway demonstrated a dose of 14.2 mSv, 3.7 mSv from cCTA, 7.7 mSv from angiography, and 2.8 mSv from PCI. The CTA + FFRCT pathway exhibited a radiation dose of 9.7 mSv, 3.7 mSv for cCTA, 4.2 mSv for angiography, and 1.8 mSv for PCI. Radiation dose exposure for CTA + FFRCT was lower than for SPECT ( P < .001). The CTA + FFRCT pathway resulted in the lowest projected death/myocardial infarction rate at 1 year (2.44%) while the dobutamine stress pathway had the highest 1-year event rate (2.84%). Conclusion Our analysis suggests that integrating FFRCT into the CTA clinical pathway may result in reduced cumulative radiation exposure, while promoting favorable clinical outcomes. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to analyze the predictive value of coronary computed tomography angiography (CCTA) and to model and validate an optimized score for prognosis of 2-year survival on the basis of a patient population with suspected coronary artery disease (CAD). Background: Coronary computed tomography angiography carries important prognostic information in addition to the detection of obstructive CAD. But it is still unclear how the results of CCTA should be interpreted in the context of clinical risk predictors. Methods: The analysis is based on a test sample of 17,793 patients and a validation sample of 2,506 patients, all with suspected CAD, from the international CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter) registry. On the basis of CCTA data and clinical risk scores, an optimized score was modeled. The endpoint was all-cause mortality. Results: During a median follow-up of 2.3 years, 347 patients died. The best CCTA parameter for prediction of mortality was the number of proximal segments with mixed or calcified plaques (C-index 0.64, p < 0.0001) and the number of proximal segments with a stenosis >50% (C-index 0.56, p = 0.002). In an optimized score including both parameters, CCTA significantly improved overall risk prediction beyond National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III) score as best clinical score. According to this score, a proximal segment with either a mixed or calcified plaque or a stenosis >50% is equivalent to a 5-year increase in age or the risk of smoking. Conclusions: In CCTA, both plaque burden and stenosis, particularly in proximal segments, carry incremental prognostic value. A prognostic score on the basis of this data can improve risk prediction beyond clinical risk scores. [Copyright &y& Elsevier]

Objectives: This study sought to examine patterns of follow-up invasive coronary angiography (ICA) and revascularization (REV) after coronary computed tomography angiography (CCTA). Background: CCTA is a noninvasive test that permits direct visualization of the extent and severity of coronary artery disease (CAD). Post-CCTA patterns of follow-up ICA and REV are incompletely defined. Methods: We examined 15,207 intermediate likelihood patients from 8 sites in 6 countries; these patients were without known CAD, underwent CCTA, and were followed up for 2.3 ± 1.2 years for all-cause mortality. Coronary artery stenosis was judged as obstructive when ≥50% stenosis was present. A multivariable logistic regression was used to estimate ICA use. A Cox proportional hazards model was used to estimate all-cause mortality. Results: During follow-up, ICA rates for patients with no CAD to mild CAD according to CCTA were low (2.5% and 8.3%), with similarly low rates of REV (0.3% and 2.5%). Most ICA procedures (79%) occurred ≤3 months of CCTA. Obstructive CAD was associated with higher rates of ICA and REV for 1-vessel (44.3% and 28.0%), 2-vessel (53.3% and 43.6%), and 3-vessel (69.4% and 66.8%) CAD, respectively. For patients with <50% stenosis, early ICA rates were elevated; over the entirety of follow-up, predictors of ICA were mild left main, mild proximal CAD, respectively, or higher coronary calcium scores. In patients with <50% stenosis, the relative hazard for death was 2.2 (p = 0.011) for ICA versus no ICA. Conversely, for patients with CAD, the relative hazard for death was 0.61 for ICA versus no ICA (p = 0.047). Conclusions: These findings support the concept that CCTA may be used effectively as a gatekeeper to ICA. [Copyright &y& Elsevier]

Introduction: Risk stratification in patients with coronary artery disease (CAD) is crucial to identify patients at risk for future events. Recently, the development of proximity extension assays (PEA) has enabled simultaneous measurement of large amounts of proteins, paving the way for the use of proteomics in large clinical populations. Aim: To investigate the ability of targeted proteomics to identify coronary computed tomography angiography (CCTA)-derived coronary plaque morphology in patients with suspected CAD. Methods: Patients with suspected CAD (n=203) underwent CCTA. Plasma levels of 358 proteins were used to generate machine learning models for either the presence of CCTA-defined high-risk coronary lesions or complete absence of coronary atherosclerosis. Model performance was tested against the Framingham risk model, refit to the current cohort. Results: A total of 196 patients with analyzable protein levels (n=333) was included for analysis. A subset of 35 proteins was identified predicting the presence of high-risk plaques. The developed machine learning model had excellent diagnostic performance with an area under the curve (AUC) of 0.79±0.01, clearly outperforming refit Framingham (AUC=0.58±0.01, p<0.05). Conversely, a different subset of 34 proteins was predictive for the absence of CAD (AUC=0.85±0.05), again outperforming refit Framingham (AUC=0.72±0.05, p<0.05). The ROC curves of the biomarker model for the presence of high-risk plaque and the biomarker model for the absence of CAD are depicted in figure 1. Conclusions: Using state-of-the-art machine learning models, trained on targeted proteomics, we defined two complementary protein signatures: one for the identification of patients with high-risk plaques and one for the identification of patients with absence of coronary atherosclerosis. Both biomarker subsets were shown to be superior to the refit Framingham in predicting presence of high-risk plaque or absence of coronary atherosclerosis. These promising findings warrant validation of the value of targeted proteomics to identify cardiovascular risk in clinical outcome studies. [ABSTRACT FROM AUTHOR]