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Purpose of Review: Cardiovascular computed tomography (CCT) is a versatile, readily available, and non-invasive imaging tool with high-resolution capabilities in many cardiovascular diseases (CVD). Our review explains the increased risk of CVD among patients with cancer due to chemoradiotherapies, shared risk factors and cancer itself and explores the expanding role of CCT in the detection, surveillance, and management of numerous CVD among these patients., Recent Findings: Recent research has highlighted the versatility and enhanced resolution capabilities of CCT in assessing a wide range of cardiovascular diseases. Early detection of cardiac changes and monitoring of disease progression in asymptomatic patients with cancer may lessen the severity of CVD. It offers an essential means to assess for coronary artery disease when patients are either unable to safely undergo stress testing for ischemia evaluation or at risk of complications from invasive coronary angiography. Furthermore, CCT extends its utility to valvular diseases, cardiomyopathies, pericardial diseases, cardiac masses, and radiation-induced cardiovascular diseases, allowing for a comprehensive, noninvasive assessment of the entire spectrum of cancer treatment associated CVD. Looking to the future, the integration of artificial intelligence and machine learning algorithms holds potential for automated image interpretation, improved precision and earlier detection of subclinical cardiac deterioration, allowing opportunities for earlier intervention and disease prevention. CCT is a useful imaging modality for assessing the myriad cardiovascular manifestations of diseases such as coronary artery disease, cardiomyopathies, pericardial disesaes, cardiac masses and radiation-induced cardiovascular diseases. CCT has several advantages. Readily available non-cardiac chest CT scans of patients with cancer may help with improved cardiovascular care, enhanced ASCVD risk stratification and toxicity surveillance., Competing Interests: Declarations. Human and Animal Rights and Informed Consent: This article does not contain any studies with human or animal subjects performed by any of the authors. Competing Interests: Maros Ferencik: Consulting: Siemens Healthineers, Elucid, HeartFlow, Cleerly, BioMarin; Advisory board: Cleerly; Stock options: Elucid. Matthew J. Budoff: Received grants from the following companies: Novo Nordisk, Novartis, AstraZeneca, HeartFlow, GE Healthcare, Amgen, and Boehringer Ingelheim, Department of Defense, Centers for Disease Contral, and the National Institutes of Health. Dr Budoff received honoraria from Novo Nordisk, Esperion, AstraZeneca, Merck, Janssen, and Eli Lilly. Eric H. Yang: Research funding/grants: CSL Behring, Boehringer Ingelheim, Eli and Lilly, Amgen, Bristol Myers Squibb, and Janssen Research and Development (all nonrelevant). Consulting fees: Xencor (nonrelevant) and Edwards Lifesciences. Speaker honoraria: Zoll Medical (nonrelevant) and National Cancer Comprehensive Cancer Center. The other authors declare that they have no conflict of interest., (© 2025. The Author(s).)

The purpose of this review is to summarize the work published by the Journal of Cardiovascular Computed Tomography (JCCT) for the year 2019, highlighting original research and new guidelines., Competing Interests: Declaration of competing interest CNC receives research support from and has received speaker fees from Siemens Healthineers. JAL serves as a consultant and holds stock options with Circle CVI and HeartFlow and receives research support from GE Healthcare. JKM receives funding from the Dalio Foundation, NIH, and GE Healthcare. JKM also serves on the scientific advisory board of Arineta and GE Healthcare, and has an equity interest in Cleerly., (Copyright © 2020 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

Opinion Statement: The increased risk for cardiovascular events in aging cancer survivors and those undergoing certain chemotherapeutic treatments has raised concern for more rigorous screening and surveillance methods above that of the general population. At this time, there are limited guidelines for how to best manage this vulnerable cohort. Questions regarding timing of screening, choice of imaging modality and risk reduction strategies-especially in those patients with known atherosclerotic disease-remain to be elucidated. Over a decade of case series, retrospective studies and clinical trials have shed light on the evolving role of cardiac computed tomography (CT) in this population, of which there is a relative paucity of data regarding its potential utility in the specific cardio-oncology population. Focusing on ability of cardiac CT to evaluate multiple cardiac and vascular structures, provide diagnostic and prognostic information, as well as assist interventional and surgical colleagues in surgical/percutaneous valve replacement and revascularization strategies is the premise for this review.

The 12th Annual Scientific Meeting of the SCCT, held from July 6 to July 9 in Washington, DC, was one of the largest to date with 724 attendants from 34 countries, 130 invited talks, 4 "Read with the Experts" sessions, 42 oral abstracts presented, 20 rapid fire posters and 164 poster presentations with the abstracts of all of these published in the JCCT. This article summarises the many themes and topics of presentation and discussion in this meeting, and the many technical advances that are likely to impact future clinical practice and feature in future meetings., (Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.)

Background: Optimal management of patients with stable chest pain relies on the prognostic information provided by noninvasive cardiovascular testing, but there are limited data from randomized trials comparing anatomic with functional testing., Methods: In the PROMISE trial (Prospective Multicenter Imaging Study for Evaluation of Chest Pain), patients with stable chest pain and intermediate pretest probability for obstructive coronary artery disease (CAD) were randomly assigned to functional testing (exercise electrocardiography, nuclear stress, or stress echocardiography) or coronary computed tomography angiography (CTA). Site-based diagnostic test reports were classified as normal or mildly, moderately, or severely abnormal. The primary end point was death, myocardial infarction, or unstable angina hospitalizations over a median follow-up of 26.1 months., Results: Both the prevalence of normal test results and incidence rate of events in these patients were significantly lower among 4500 patients randomly assigned to CTA in comparison with 4602 patients randomly assigned to functional testing (33.4% versus 78.0%, and 0.9% versus 2.1%, respectively; both P <0.001). In CTA, 54.0% of events (n=74/137) occurred in patients with nonobstructive CAD (1%-69% stenosis). Prevalence of obstructive CAD and myocardial ischemia was low (11.9% versus 12.7%, respectively), with both findings having similar prognostic value (hazard ratio, 3.74; 95% confidence interval [CI], 2.60-5.39; and 3.47; 95% CI, 2.42-4.99). When test findings were stratified as mildly, moderately, or severely abnormal, hazard ratios for events in comparison with normal tests increased proportionally for CTA (2.94, 7.67, 10.13; all P <0.001) but not for corresponding functional testing categories (0.94 [ P =0.87], 2.65 [ P =0.001], 3.88 [ P <0.001]). The discriminatory ability of CTA in predicting events was significantly better than functional testing (c-index, 0.72; 95% CI, 0.68-0.76 versus 0.64; 95% CI, 0.59-0.69; P =0.04). If 2714 patients with at least an intermediate Framingham Risk Score (>10%) who had a normal functional test were reclassified as being mildly abnormal, the discriminatory capacity improved to 0.69 (95% CI, 0.64-0.74)., Conclusions: Coronary CTA, by identifying patients at risk because of nonobstructive CAD, provides better prognostic information than functional testing in contemporary patients who have stable chest pain with a low burden of obstructive CAD, myocardial ischemia, and events., Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01174550., (© 2017 American Heart Association, Inc.)

Physicians practicing cardiovascular medicine are every day confronted with patients presenting with symptoms suggestive of an acute coronary syndrome (ACS). Over the years, there have been substantial technical advances, such as the introduction of new non-invasive imaging techniques and the introduction of new highly sensitive cardiac biomarkers. Physicians have adopted these new assets and have become more experienced with them thus improving medical care. Nevertheless, the search for an efficient, yet safe diagnostic work-up for patients presenting with symptoms suggestive of ACS is ongoing. A large proportion of patients will require some form of non-invasive testing and the choice for the diagnostic modality as well as its timing are important steps in this process. Cardiac computed tomography (CT), a non-invasive imaging technique that rapidly provides visualization of the coronary artery tree, is an attractive option, with its unparalleled negative predictive value for obstructive coronary artery disease (CAD). With the introduction of highly-sensitive troponins (hsTn), the role of non-invasive testing, including cardiac CT, has changed. This review will provide an oversight on what is known about cardiac CT in acute chest presentations. Furthermore, we will discuss the changing role of cardiac CT in the era of hsTn and the possibility of their combined use in the work-up of suspected ACS patients. hsTn is currently an established tool for the diagnosis and triage of patients with suspected ACS. The role of cardiac CT has shifted now to a secondary, comprehensive rule-out test in patients with inconclusive biomarker status, providing information on stenosis severity, plaque burden, high-risk features and the presence of other serious conditions that can also give rise to hsTn.

Background and Aims: To determine whether epicardial (EAT) and paracardial adipose tissue (PAT) volume and attenuation are associated with high-risk coronary plaque features., Methods: In subjects with suspected acute coronary syndrome (ACS) enrolled in the ROMICAT II trial, EAT and PAT volumes indexed to body surface area (BSA) and attenuation were measured on non-contrast coronary artery calcium score (CACS) CT. High-risk plaque features (napkin-ring sign, positive remodeling, low density plaque, spotty calcium) and stenosis were assessed on coronary CT angiography (CTA). The association of EAT and PAT volume and attenuation with high-risk plaque and whether this was independent of clinical risk assessment, CACS and significant coronary artery disease (CAD) was determined., Results: Of 467 (mean 54 ± 8 yrs, 53% male) with CACS and CTA, 167 (36%) had high-risk plaque features. Those with high-risk plaque had significantly higher indexed EAT (median 59 (Q1-Q3:45-75) cc/m(2) vs. 49 (35-65) cc/m(2), p < 0.001) and PAT volume (median:51 (36-73) cc/m(2) vs. 33 (22-52) cc/m(2), p < 0.001). Higher indexed EAT volume was associated with high-risk plaque [univariate OR 1.02 (95%-CI:1.01-1.03) per cc/m(2) of EAT, p < 0.001], which remained significant [univariate OR 1.04 (95%-CI:1.00-1.08) per cc/m(2) of EAT, p = 0.040] after adjustment for risk factors, CACS, and stenosis ≥50%. Higher indexed PAT volume was associated with high-risk plaque in univariate analysis [OR 1.02 (1.01-1.03) per cc/m(2) of PAT, p < 0.001], though this was not significant in multivariate analysis. At a threshold of >62.3 cc/m(2), EAT volume was associated with high-risk plaque [univariate OR 2.50 (95%-CI:1.69-3.72), p < 0.001)], which remained significant [OR 1.83 (95%-CI:1.10-3.05), p = 0.020] after adjustment. Subjects with high-risk plaque had lower mean attenuation EAT (-88.1 vs. -86.9 HU, p = 0.008) and PAT (-106 vs. -103 HU, p < 0.001), though this was not significant in multivariable analysis., Conclusions: Greater volumes of EAT are associated with high-risk plaque independent of risk factors, CACS and obstructive CAD. This observation supports possible local influence of EAT on development of high-risk coronary plaque., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Background: Coronary computed tomography angiography (CTA) can be used to detect and quantitatively assess high-risk plaque features., Objective: To validate the ROMICAT score, which was derived using semi-automated quantitative measurements of high-risk plaque features, for the prediction of ACS., Material and Methods: We performed quantitative plaque analysis in 260 patients who presented to the emergency department with suspected ACS in the ROMICAT II trial. The readers used a semi-automated software (QAngio, Medis medical imaging systems BV) to measure high-risk plaque features (volume of <60HU plaque, remodeling index, spotty calcium, plaque length) and diameter stenosis in all plaques. We calculated a ROMICAT score, which was derived from the ROMICAT I study and applied to the ROMICAT II trial. The primary outcome of the study was diagnosis of an ACS during the index hospitalization., Results: Patient characteristics (age 57 ± 8 vs. 56 ± 8 years, cardiovascular risk factors) were not different between those with and without ACS (prevalence of ACS 7.8%). There were more men in the ACS group (84% vs. 59%, p = 0.005). When applying the ROMICAT score derived from the ROMICAT I trial to the patient population of the ROMICAT II trial, the ROMICAT score (OR 2.9, 95% CI 1.4-6.0, p = 0.003) was a predictor of ACS after adjusting for gender and ≥ 50% stenosis. The AUC of the model containing ROMICAT score, gender, and ≥ 50% stenosis was 0.91 (95% CI 0.86-0.96) and was better than with a model that included only gender and ≥ 50% stenosis (AUC 0.85, 95%CI 0.77-0.92; p = 0.002)., Conclusions: The ROMICAT score derived from semi-automated quantitative measurements of high-risk plaque features was an independent predictor of ACS during the index hospitalization and was incremental to gender and presence of ≥ 50% stenosis., (Copyright © 2015 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

Objectives: This study compared diagnostic accuracy of conventional troponin/traditional coronary artery disease (CAD) assessment and highly sensitive troponin (hsTn) I/advanced CAD assessment for acute coronary syndrome (ACS) during the index hospitalization., Background: hsTnI and advanced assessment of CAD using coronary computed tomography angiography (CTA) are promising candidates to improve the accuracy of emergency department evaluation of patients with suspected ACS., Methods: We performed an observational cohort study in patients with suspected ACS enrolled in the ROMICAT II (Rule Out Myocardial Infarction/Ischemia using Computer Assisted Tomography) trial and randomized to coronary CTA who also had hsTnI measurement at the time of the emergency department presentation. We assessed coronary CTA for traditional (no CAD, nonobstructive CAD, ≥50% stenosis) and advanced features of CAD (≥50% stenosis, high-risk plaque features: positive remodeling, low <30-Hounsfield units plaque, napkin-ring sign, spotty calcium)., Results: Of 160 patients (mean age: 53 ± 8 years, 40% women) 10.6% were diagnosed with ACS. The ACS rate in patients with hsTnI below the limit of detection (n = 9, 5.6%), intermediate (n = 139, 86.9%), and above the 99th percentile (n = 12, 7.5%) was 0%, 8.6%, and 58.3%, respectively. Absence of ≥50% stenosis and high-risk plaque ruled out ACS in patients with intermediate hsTnI (n = 87, 54.4%; ACS rate 0%), whereas patients with both ≥50% stenosis and high-risk plaque were at high risk (n = 13, 8.1%; ACS rate 69.2%) and patients with either ≥50% stenosis or high-risk plaque were at intermediate risk for ACS (n = 39, 24.4%; ACS rate 7.7%). hsTnI/advanced coronary CTA assessment significantly improved the diagnostic accuracy for ACS as compared to conventional troponin/traditional coronary CTA (area under the curve 0.84, 95% confidence interval [CI]: 0.80 to .88 vs. 0.74, 95% CI: 0.70 to 0.78; p < 0.001)., Conclusions: hsTnI at the time of presentation followed by early advanced coronary CTA assessment improves the risk stratification and diagnostic accuracy for ACS as compared to conventional troponin and traditional coronary CTA assessment. (Multicenter Study to Rule Out Myocardial Infarction/Ischemia by Cardiac Computed Tomography [ROMICAT-II]; NCT01084239)., (Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Purpose: To determine the association between nonalcoholic fatty liver disease (NAFLD) and the presence of high-risk coronary atherosclerotic plaque as assessed with coronary computed tomographic (CT) angiography., Materials and Methods: This study was approved by the local ethics committees; informed consent was obtained. Patients randomized to the coronary CT angiography arm of the Rule Out Myocardial Infarction using Computer Assisted Tomography, or ROMICAT, II trial who underwent both nonenhanced CT to assess calcium score and contrast material-enhanced coronary CT angiography were included. Readers assessed coronary CT angiography images for the presence of coronary plaque, significant stenosis (≥50%), and high-risk plaque features (positive remodeling, CT attenuation < 30 HU, napkin-ring sign, spotty calcium). NAFLD was defined as hepatic steatosis at nonenhanced CT (liver minus spleen CT attenuation < 1 HU) without evidence of clinical liver disease, liver cirrhosis, or alcohol abuse. To determine the association between high-risk plaque and NAFLD, univariable and multivariable logistic regression analyses were performed, with high-risk plaque as a dependent variable and NAFLD, traditional risk factors, and extent of coronary atherosclerosis as independent variables., Results: Overall, 182 (40.9%) of 445 patients had CT evidence of NAFLD. High-risk plaque was more frequent in patients with NAFLD than in patients without NAFLD (59.3% vs 19.0%, respectively; P < .001). The association between NAFLD and high-risk plaque (odds ratio, 2.13; 95% confidence interval: 1.18, 3.85) persisted after adjusting for the extent and severity of coronary atherosclerosis and traditional risk factors., Conclusion: NAFLD is associated with advanced high-risk coronary plaque, independent of traditional cardiovascular risk factors and the extent and severity of coronary artery disease.

Objectives: To evaluate whether iterative reconstruction algorithms improve the diagnostic accuracy of coronary CT angiography (CCTA) for detection of lipid-core plaque (LCP) compared to histology., Methods and Materials: CCTA and histological data were acquired from three ex vivo hearts. CCTA images were reconstructed using filtered back projection (FBP), adaptive-statistical (ASIR) and model-based (MBIR) iterative algorithms. Vessel cross-sections were co-registered between FBP/ASIR/MBIR and histology. Plaque area <60 HU was semiautomatically quantified in CCTA. LCP was defined by histology as fibroatheroma with a large lipid/necrotic core. Area under the curve (AUC) was derived from logistic regression analysis as a measure of diagnostic accuracy., Results: Overall, 173 CCTA triplets (FBP/ASIR/MBIR) were co-registered with histology. LCP was present in 26 cross-sections. Average measured plaque area <60 HU was significantly larger in LCP compared to non-LCP cross-sections (mm(2): 5.78 ± 2.29 vs. 3.39 ± 1.68 FBP; 5.92 ± 1.87 vs. 3.43 ± 1.62 ASIR; 6.40 ± 1.55 vs. 3.49 ± 1.50 MBIR; all p < 0.0001). AUC for detecting LCP was 0.803/0.850/0.903 for FBP/ASIR/MBIR and was significantly higher for MBIR compared to FBP (p = 0.01). MBIR increased sensitivity for detection of LCP by CCTA., Conclusion: Plaque area <60 HU in CCTA was associated with LCP in histology regardless of the reconstruction algorithm. However, MBIR demonstrated higher accuracy for detecting LCP, which may improve vulnerable plaque detection by CCTA., Key Points: • A low attenuation plaque area is associated with the presence of lipid-core plaque • MBIR leads to higher diagnostic accuracy for detecting lipid-core plaque • The benefit of MBIR is mainly due to increased sensitivity at high specificities • Semiautomated CCTA assessment can detect vulnerable plaques non-invasively.

Background: It is not known whether high-risk plaque, as detected by coronary computed tomography angiography (CTA), permits improved early diagnosis of acute coronary syndromes (ACS) independently to the presence of significant coronary artery disease (CAD) in patients with acute chest pain., Objectives: The primary aim of this study was to determine whether high-risk plaque features, as detected by CTA in the emergency department (ED), may improve diagnostic certainty of ACS independently and incrementally to the presence of significant CAD and clinical risk assessment in patients with acute chest pain but without objective evidence of myocardial ischemia or myocardial infarction (MI)., Methods: We included patients randomized to the coronary CTA arm of the ROMICAT-II (Rule Out Myocardial Infarction/Ischemia Using Computer-Assisted Tomography II) trial. Readers assessed coronary CTA qualitatively for the presence of nonobstructive CAD (1% to 49% stenosis), significant CAD (≥50% or ≥70% stenosis), and the presence of at least 1 of the high-risk plaque features (positive remodeling, low <30 Hounsfield units plaque, napkin-ring sign, spotty calcium). In logistic regression analysis, we determined the association of high-risk plaque with ACS (MI or unstable angina pectoris) during the index hospitalization and whether this was independent of significant CAD and clinical risk assessment., Results: Overall, 37 of 472 patients who underwent coronary CTA with diagnostic image quality (mean age 53.9 ± 8.0 years; 52.8% men) had ACS (7.8%; MI n = 5; unstable angina pectoris n = 32). CAD was present in 262 patients (55.5%; nonobstructive CAD in 217 patients [46.0%] and significant CAD with ≥50% stenosis in 45 patients [9.5%]). High-risk plaques were more frequent in patients with ACS and remained a significant predictor of ACS (odds ratio [OR]: 8.9; 95% CI: 1.8 to 43.3; p = 0.006) after adjustment for ≥50% stenosis (OR: 38.6; 95% CI: 14.2 to 104.7; p < 0.001) and clinical risk assessment (age, sex, number of cardiovascular risk factors). Similar results were observed after adjustment for ≥70% stenosis., Conclusions: In patients presenting to the ED with acute chest pain but negative initial electrocardiogram and troponin, presence of high-risk plaques on coronary CTA increased the likelihood of ACS independent of significant CAD and clinical risk assessment (age, sex, and number of cardiovascular risk factors). (Multicenter Study to Rule Out Myocardial Infarction by Cardiac Computed Tomography [ROMICAT-II]; NCT01084239)., (Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Most acute coronary syndromes are caused by sudden luminal thrombosis due to atherosclerotic plaque rupture or erosion. Preventing such an event seems to be the only effective strategy to reduce mortality and morbidity of coronary heart disease. Coronary lesions prone to rupture have a distinct morphology compared with stable plaques, and provide a unique opportunity for noninvasive imaging to identify vulnerable plaques before they lead to clinical events. The submillimeter spatial resolution and excellent image quality of modern computed tomography (CT) scanners allow coronary atherosclerotic lesions to be detected, characterized, and quantified. Large plaque volume, low CT attenuation, napkin-ring sign, positive remodelling, and spotty calcification are all associated with a high risk of acute cardiovascular events in patients. Computation fluid dynamics allow the calculation of lesion-specific endothelial shear stress and fractional flow reserve, which add functional information to plaque assessment using CT. The combination of morphologic and functional characteristics of coronary plaques might enable noninvasive detection of vulnerable plaques in the future.

Background: Although a tube potential of 140 kV is available on most computed tomography (CT) scanners, its incremental diagnostic value versus 120 kV has been controversial., Purpose: To retrospectively evaluate the image quality and radiation exposure of cardiac computed tomography angiography (CCTA) performed at 140 kV in comparison to CCTA at 120 kV in overweight and moderately obese patients., Material and Methods: Eighty-eight patients who were referred for CCTA between January 2010 and May 2012 were included. Forty-four patients who were overweight or moderately obese (body mass index [BMI], 25-35 kg/m(2)) underwent CCTA with dual-source CT (DSCT) scanner at 140 kV. Forty-four match controls who underwent CCTA with DSCT at 120 kV were identified per BMI, average heart rate, scan indication, and scan acquisition mode. All scans were performed per routine protocols with direct physician supervision. Quantitative image metrics (CT attenuation, image noise, contrast-to-noise ratio [CNR], and signal-to-noise ratio [SNR] of left main [LM] and proximal right coronary artery [RCA]) were assessed. Effective radiation dose was compared between the two groups., Results: Overall, all scans were diagnostic without any non-evaluable coronary segment per clinical report. 140 kV had a lower attenuation and image noise versus 120 kV (P<0.01). Both SNR and CNR of proximal coronary arteries were similar between 140 kV and 120 kV (SNR, LM P=0.93, RCA P=0.62; CNR, LM P=0.57, RCA P=0.77). 140 kV was associated with a 35.3% increase in effective radiation dose as compared with 120 kV (5.1 [3.6-8.2] vs. 3.3 [2.0-5.1] mSv, respectively; P<0.01)., Conclusion: 140 kV CCTA resulted in similar image quality but a higher effective radiation dose in comparison to 120 kV CCTA. Therefore, in overweight and moderately obese patients, a tube potential of 120 kV may be sufficient for CCTA with diagnostic image quality., (© The Foundation Acta Radiologica 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.)

Aims: To compare the accuracy of two plaque delineation methods for coronary computed tomographic angiography (CTA) to identify lipid-core plaque (LCP) using histology as the reference standard., Methods and Results: Five ex vivo hearts were analysed by CTA and histology. LCP was defined by histology as fibroatheroma with core diameter/circumference >200 μm/>60° and cap thickness <450 μm. In CTA, plaque was manually delineated either as the difference between the inner and outer vessel walls (Method A) or as a direct tracing of plaque (Method B). Low-attenuation plaque was defined as an area with <90 Hounsfield units. Of 446 co-registered cross-sections, 55 (12%) contained LCP. In CTA, low-attenuation plaque area was larger as assessed with Method A compared with Method B (difference: 120 ± 60%). Although low-attenuation plaque was associated with the presence of LCP, the delineation Method B yielded higher diagnostic accuracy than Method A [area under the curve (AUC): 0.831 vs. 0.780, respectively, P = 0.005]. After excluding 'normal' cross-sections by CTA (n = 117), AUC for detecting LCP became similar between both methods (0.767 vs. 0.729, P = 0.07, respectively)., Conclusion: Low-attenuation plaque in CTA is a diagnostic tool for LCP but prone to error if plaque is defined as the area between the inner and outer vessel walls and normal cross-sections are included in the assessment.

Purpose: In coronary computed tomographic angiography (CTA), low attenuation of coronary atherosclerotic plaque is associated with lipid-rich plaques. However, an overlap in Hounsfield units (HU) between fibrous and lipid-rich plaque as well as an influence of luminal enhancement on plaque attenuation was observed and may limit accurate detection of lipid-rich plaques by CTA. We sought to determine whether the quantitative histogram analysis improves accuracy of the detection of lipid-core plaque (LCP) in ex vivo hearts by validation against histological analysis., Materials and Methods: Human donor hearts were imaged with a 64-slice computed tomographic scanner using a standard coronary CTA protocol, optical coherence tomography (OCT), a histological analysis. Lipid-core plaque was defined in the histological analysis as any fibroatheroma with a lipid/necrotic core diameter of greater than 200 μm and a circumference greater than 60 degrees as well as a cap thickness of less than 450 μm. In OCT, lipid-rich plaque was determined as a signal-poor region with diffuse borders in 2 quadrants or more. In CTA, the boundaries of the noncalcified plaque were manually traced. The absolute and relative areas of low attenuation plaque based on pixels with less than 30, less than 60, and less than 90 HU were calculated using quantitative histogram analysis., Results: From 5 hearts, a total of 446 cross sections were coregistered between CTA and the histological analysis. Overall, 55 LCPs (12%) were identified by the histological analysis. In CTA, the absolute and relative areas of low attenuation plaque less than 30, less than 60, and less than 90 HU were 0.14 (0.31) mm2 (4.22% [9.02%]), 0.69 (0.95) mm2 (18.28% [21.22%]), and 1.35 (1.54) mm2 (35.65% [32.07%]), respectively. The low attenuation plaque area correlated significantly with histological lipid content (lipid/necrotic core size [in square millimeter] and a portion of lipid/necrotic core on the entire plaque) at all thresholds but was the strongest at less than 60 HU (r = 0.53 and r = 0.48 for the absolute and relative areas, respectively). Using a threshold of 1.0 mm2 or greater, the absolute plaque area of less than 60 HU in CTA yielded 69% sensitivity and 80% specificity to detect LCP, whereas sensitivity and specificity were 73% and 71% for using 25.0% or higher relative area less than 60 HU. The discriminatory ability of CTA for LCP was similar between the absolute and relative areas (the area under the curve, 0.744 versus 0.722; P = 0.37). Notably, the association of the low attenuation plaque area in CTA with LCP was not altered by the luminal enhancement for the relative (P = 0.48) but for the absolute measurement (P = 0.03). Similar results were achieved when validated against lipid-rich plaque by OCT in a subset of 285 cross sections., Conclusions: In ex vivo conditions, the relative area of coronary atherosclerotic plaque less than 60 HU in CTA as derived from quantitative histogram analysis has good accuracy to detect LCP as compared with a histological analysis independent of differences in luminal contrast enhancement.

Background: Efficiency of coronary CT angiography (CCTA) in clinical practice depends on precise reporting and accurate result interpretation., Objective: We sought to assess referring clinicians' understanding of patients' coronary artery disease (CAD) severity and to compare satisfactions of the free-form impression (FFI) with satisfactions of the structured impression (SI) section of CCTA reports., Materials and Methods: Fifty clinical CCTA reports from May 2011 to April 2012 were retrospectively selected (25 FFI and 25 SI), to include cases with the entire spectrum of CAD (6 categories encompassing normal, minimal, mild, moderate, severe stenosis, and occlusion). A survey containing only randomized blinded impressions was distributed to 4 cardiologists and 2 cardiac imaging specialists. Clinician interpretation was examined regarding (Q1) worst stenosis severity, (Q2) number of vessels with significant stenosis, and (Q3) the presence of nonevaluable segments. Agreement proportions and Cohen's kappa were evaluated between FFI versus SI. Satisfactions were measured with respect to content, clarity, and clinical effectiveness., Results: Q1 agreement was excellent for both FFI and SI (by 6 categories: 80% versus 85%; P > .05; kappa: 0.87 versus 0.89; by no CAD versus nonsignificant versus significant CAD: 99% versus 97%; P > .05; kappa: 0.99 versus 0.94). Q2 agreement improved from fair to moderate (53% versus 68%; P = .04; kappa 0.31 versus 0.52). Q3 agreement was moderate (90% versus 87%; P > .05; kappa 0.57 versus 0.58). Satisfactions with impressions were high and similar for FFI and SI for clinicians., Conclusion: Structured impressions were shown to improve result interpretation agreement from fair to moderate with regard to the number of vessels with significant stenosis., (Copyright © 2013 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

Coronary CT angiography is an effective, evidence-based strategy for evaluating acute chest pain in the emergency department for patients at low-to-intermediate risk of acute coronary syndrome. Recent multicenter trials have reported that coronary CT angiography is safe, reduces time to diagnosis, facilitates discharge, and may lower overall cost compared with routine care. Herein, we provide a 10-step approach for establishing a successful coronary CT angiography program in the emergency department. The importance of strategic planning and multidisciplinary collaboration is emphasized. Patient selection and preparation guidelines for coronary CT angiography are reviewed with straightforward protocols that can be adapted and modified to clinical sites, depending on available cardiac imaging capabilities. Technical parameters and patient-specific modifications are also highlighted to maximize the likelihood of diagnostic quality examinations. Practical suggestions for quality control, process monitoring, and standardized reporting are reviewed. Finally, the role of a "triple rule-out" protocol is featured in the context of acute chest pain evaluation in the emergency department., (Copyright © 2013 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

Objectives: This study sought to determine the accuracy of plaque pattern assessment by coronary computed tomography angiography (CCTA) to differentiate between early and advanced atherosclerotic lesions as defined by histology., Background: A ringlike attenuation pattern of coronary atherosclerotic plaques termed as napkin-ring sign (NRS) was described in CCTA of patients who had acute coronary syndrome., Methods: All procedures were performed in accordance with local and federal regulations and the Declaration of Helsinki. Approval of the local ethics committees was obtained. We investigated 21 coronary arteries of 7 donor hearts. Overall, 611 histological sections were obtained and coregistered with CCTA images. The CCTA cross sections were read in random order for conventional plaque categories (noncalcified [NCP], mixed [MP], calcified [CP]) and plaque patterns (homogenous, heterogeneous with no napkin-ring sign [non-NRS], and heterogeneous with NRS)., Results: No plaque was detected in 134 (21.9%), NCP in 254 (41.6%), MP in 191 (31.3%), and CP in 32 (5.2%) CCTA cross sections. The NCP and MP were further classified into homogenous plaques (n = 207, 46.5%), non-NRS plaques (n = 200, 44.9%), and NRS plaques (n = 38, 8.6%). The specificities of NCP and MP to identify advanced lesions were moderate (57.9%, 95% confidence interval [CI]: 50.1% to 65.6%, and 72.1%, 95% CI: 64.7% to 79.4%, respectively), which were similar to the homogenous and heterogeneous plaques (62.6%, 95% CI: 54.8% to 70.3%, and 67.3%, 95% CI: 58.6% to 76.1%, respectively). In contrast, the specificity of the NRS to identify advanced lesions was excellent (98.9%, 95% CI: 97.6% to 100%). The diagnostic performance of the pattern-based scheme to identify advanced lesions was significantly better than that of the conventional plaque scheme (area under the curve: 0.761 vs. 0.678, respectively; p = 0.001)., Conclusions: The assessment of the plaque pattern improves diagnostic accuracy of CCTA to identify advanced atherosclerotic lesions. The CCTA finding of NRS has a high specificity and high positive predictive value for the presence of advanced lesions., (Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objectives: The objective was to determine the association of four clinical risk scores and coronary plaque burden as detected by computed tomography (CT) with the outcome of acute coronary syndrome (ACS) in patients with acute chest pain. The hypothesis was that the combination of risk scores and plaque burden improved the discriminatory capacity for the diagnosis of ACS., Methods: The study was a subanalysis of the Rule Out Myocardial Infarction Using Computer-Assisted Tomography (ROMICAT) trial-a prospective observational cohort study. The authors enrolled patients presenting to the emergency department (ED) with a chief complaint of acute chest pain, inconclusive initial evaluation (negative biomarkers, nondiagnostic electrocardiogram [ECG]), and no history of coronary artery disease (CAD). Patients underwent contrast-enhanced 64-multidetector-row cardiac CT and received standard clinical care (serial ECG, cardiac biomarkers, and subsequent diagnostic testing, such as exercise treadmill testing, nuclear stress perfusion imaging, and/or invasive coronary angiography), as deemed clinically appropriate. The clinical providers were blinded to CT results. The chest pain score was calculated and the results were dichotomized to ≥10 (high-risk) and <10 (low-risk). Three risk scores were calculated, Goldman, Sanchis, and Thrombolysis in Myocardial Infarction (TIMI), and each patient was assigned to a low-, intermediate-, or high-risk category. Because of the low number of subjects in the high-risk group, the intermediate- and high-risk groups were combined into one. CT images were evaluated for the presence of plaque in 17 coronary segments. Plaque burden was stratified into none, intermediate, and high (zero, one to four, and more than four segments with plaque). An outcome panel of two physicians (blinded to CT findings) established the primary outcome of ACS (defined as either an acute myocardial infarction or unstable angina) during the index hospitalization (from the presentation to the ED to the discharge from the hospital). Logistic regression modeling was performed to examine the association of risk scores and coronary plaque burden to the outcome of ACS. Unadjusted models were individually fitted for the coronary plaque burden and for Goldman, Sanchis, TIMI, and chest pain scores. In adjusted analyses, the authors tested whether the association between risk scores and ACS persisted after controlling for the coronary plaque burden. The prognostic discriminatory capacity of the risk scores and plaque burden for ACS was assessed using c-statistics. The differences in area under the receiver-operating characteristic curve (AUC) and c-statistics were tested by performing the -2 log likelihood ratio test of nested models. A p value <0.05 was considered statistically significant., Results: Among 368 subjects, 31 (8%) subjects were diagnosed with ACS. Goldman (AUC = 0.61), Sanchis (AUC = 0.71), and TIMI (AUC = 0.63) had modest discriminatory capacity for the diagnosis of ACS. Plaque burden was the strongest predictor of ACS (AUC = 0.86; p < 0.05 for all comparisons with individual risk scores). The combination of plaque burden and risk scores improved prediction of ACS (plaque + Goldman AUC = 0.88, plaque + Sanchis AUC = 0.90, plaque + TIMI AUC = 0.88; p < 0.01 for all comparisons with coronary plaque burden alone)., Conclusions: Risk scores (Goldman, Sanchis, TIMI) have modest discriminatory capacity and coronary plaque burden has good discriminatory capacity for the diagnosis of ACS in patients with acute chest pain. The combined information of risk scores and plaque burden significantly improves the discriminatory capacity for the diagnosis of ACS., (© 2012 by the Society for Academic Emergency Medicine.)

Cardiac allograft vasculopathy (CAV) is the main cause of morbidity and mortality beyond 1 year after heart transplantation. Ischemic symptoms are usually not present because of the denervated allograft and diffuse nature of the disease. Patients present with heart failure, ventricular arrhythmia, or sudden cardiac death as a result of advanced CAV. Therefore, clinical evaluation includes routine annual invasive coronary angiography (ICA) and transthoracic echocardiography to screen for CAV. Noninvasive imaging methods for the detection of CAV have not been widely adopted. Computed tomography (CT) permits detection of coronary stenoses and plaque in the nontransplant population. The strength of CT is its high negative predictive value. These attributes predispose CT to a role of a gatekeeper for further invasive testing in heart transplant recipients. We reviewed the available literature on CT evaluation of CAV. Technical challenges (eg, high heart rates, need for contrast and radiation, image quality) specific for patients who have received a heart transplant are emphasized, and solutions, including appropriate protocols and advances through the new CT technology, are summarized. We systematically analyze the results of studies that report the diagnostic performance of cardiac CT for the detection of coronary stenoses compared with ICA. Similar analysis is performed for the comparison between CT and intravascular ultrasound scanning for the detection of nonobstructive CAV. Finally, we suggest future directions in cardiac CT imaging research of CAV., (Copyright © 2012 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

Introduction: Successful catheter ablation of atrial fibrillation (AF) requires the creation of transmural lesions in the left atrium (LA). In addition, cardiac perforation is more likely to occur in areas of thin walls. The LA wall thickness is thus relevant both for procedural efficacy and safety. This study sought to evaluate the regional LA wall thickness in patients with AF., Methods: The LA muscular wall thickness (excluding fat) was measured by 64 slice cardiac computed tomography (CT) in 60 patients with persistent AF prior to catheter ablation procedures. Measurements were performed in all patients at 12 distinct LA locations, including 3 at the roof (right, middle left), 3 at the floor (right, middle, left), 4 at the posterior wall (right, middle, middle-superior, left), 1 at the left lateral ridge (LLR), and 1 at the mitral isthmus., Results: There was a large range of LA wall thickness (average thickness 1.89 ± 0.48 mm, range 0.5-3.5 mm). In addition, there were significant regional differences in LA wall thickness. In particular, the LA roof was significantly thicker than the posterior wall and floor (P < 0.001), the LLR was significantly thicker than most regions (P < 0.04), and the mitral isthmus was also significantly thicker than the posterior wall (P < 0.001) and floor (P < 0.001)., Conclusions: In patients with persistent AF, there is inter- and intra-patient variability in the thickness of the LA muscular wall. In most patients, however, the roof, mitral isthmus, and the ridge between the pulmonary veins and appendage are thicker compared to the posterior wall and floor., (© 2011 Wiley Periodicals, Inc.)

Objectives: The aim of this study was to determine the 2-year prognostic value of cardiac computed tomography (CT) for predicting major adverse cardiac events (MACE) in patients presenting to the emergency department (ED) with acute chest pain., Background: CT has high potential for early triage of acute chest pain patients. However, there is a paucity of data regarding the prognostic value of CT in this ED cohort., Methods: We followed 368 patients from the ROMICAT (Rule Out Myocardial Infarction Using Computer Assisted Tomography) trial (age 53 ± 12 years; 61% male) who presented to the ED with acute chest pain, negative initial troponin, and a nonischemic electrocardiogram for 2 years. Contrast-enhanced 64-slice CT was obtained during index hospitalization, and caregivers and patients remained blinded to the results. CT was assessed for the presence of plaque, stenosis (>50% luminal narrowing), and left ventricular regional wall motion abnormalities (RWMA). The primary endpoint was MACE, defined as composite cardiac death, nonfatal myocardial infarction, or coronary revascularization., Results: Follow-up was completed in 333 patients (90.5%) with a median follow-up period of 23 months. At the end of the follow-up period, 25 patients (6.8%) experienced 35 MACE (no cardiac deaths, 12 myocardial infarctions, and 23 revascularizations). Cumulative probability of 2-year MACE increased across CT strata for coronary artery disease (CAD) (no CAD 0%; nonobstructive CAD 4.6%; obstructive CAD 30.3%; log-rank p < 0.0001) and across combined CT strata for CAD and RWMA (no stenosis or RWMA 0.9%; 1 feature-either RWMA [15.0%] or stenosis [10.1%], both stenosis and RWMA 62.4%; log-rank p < 0.0001). The c statistic for predicting MACE was 0.61 for clinical Thrombolysis In Myocardial Infarction risk score and improved to 0.84 by adding CT CAD data and improved further to 0.91 by adding RWMA (both p < 0.0001)., Conclusions: CT coronary and functional features predict MACE and have incremental prognostic value beyond clinical risk score in ED patients with acute chest pain. The absence of CAD on CT provides a 2-year MACE-free warranty period, whereas coronary stenosis with RWMA is associated with the highest risk of MACE., (Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

The pathologic evolution of coronary artery atherosclerosis occurs slowly over decades, which may provide an opportunity for diagnostic imaging to identify patients before clinical events evolve. Cardiac computed tomography (CT) is an emerging noninvasive imaging tool, which can visualize the entire coronary tree with submillimeter resolution. We reviewed the current status of cardiac CT to qualitatively and quantitatively determine coronary plaque dimensions and composition, and its potential to improve our understanding of the natural history of coronary artery disease as well as prevention of cardiovascular events., (Copyright 2009 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

Objectives: This study was designed to determine the usefulness of coronary computed tomography angiography (CTA) in patients with acute chest pain., Background: Triage of chest pain patients in the emergency department remains challenging., Methods: We used an observational cohort study in chest pain patients with normal initial troponin and nonischemic electrocardiogram. A 64-slice coronary CTA was performed before admission to detect coronary plaque and stenosis (>50% luminal narrowing). Results were not disclosed. End points were acute coronary syndrome (ACS) during index hospitalization and major adverse cardiac events during 6-month follow-up., Results: Among 368 patients (mean age 53 +/- 12 years, 61% men), 31 had ACS (8%). By coronary CTA, 50% of these patients were free of coronary artery disease (CAD), 31% had nonobstructive disease, and 19% had inconclusive or positive computed tomography for significant stenosis. Sensitivity and negative predictive value for ACS were 100% (n = 183 of 368; 95% confidence interval [CI]: 98% to 100%) and 100% (95% CI: 89% to 100%), respectively, with the absence of CAD and 77% (95% CI: 59% to 90%) and 98% (n = 300 of 368, 95% CI: 95% to 99%), respectively, with significant stenosis by coronary CTA. Specificity of presence of plaque and stenosis for ACS were 54% (95% CI: 49% to 60%) and 87% (95% CI: 83% to 90%), respectively. Only 1 ACS occurred in the absence of calcified plaque. Both the extent of coronary plaque and presence of stenosis predicted ACS independently and incrementally to Thrombolysis In Myocardial Infarction risk score (area under curve: 0.88, 0.82, vs. 0.63, respectively; all p < 0.0001)., Conclusions: Fifty percent of patients with acute chest pain and low to intermediate likelihood of ACS were free of CAD by computed tomography and had no ACS. Given the large number of such patients, early coronary CTA may significantly improve patient management in the emergency department.

Coronary computed tomography angiography (CTA) may be helpful to manage patients with chronic coronary occlusions. The aim of this study was to determine the sensitivity and specificity of CTA to detect the presence and extent of coronary collaterals as compared to invasive coronary angiography (ICA). We retrospectively evaluated 26 patients who underwent both coronary CTA and ICA within 3 weeks and demonstrated a total coronary occlusion (TIMI grade 0) in one of the major coronary arteries. CTA was performed using a 64-slice multidetector CT. The presence, and extent of collateralization was assessed by two blinded observers using the Rentrop classification for ICA. CTA accurately identified the presence and location of all 26 total occlusions. The presence of any collaterals was accurately detected in 21/23 patients [sensitivity 91% (CI: 71-98%)] and the absence in three patients [specificity 100% (CI: 29%-100%)]. The sensitivity of coronary CTA to identify patients with collateralization increased from 91 to 94% (CI: 71-99%) and 100% (CI: 59-100%) for collaterals Rentrop grade 2 and 3 in ICA, respectively. Coronary CTA accurately detects the presence of any coronary collateralization in patients with total occlusions. Although CT technology is currently limited in the assessment of individual collaterals and smaller vessels, it may be helpful in the management of patients with total occlusions.

Purpose: To evaluate the accuracy of 64-section multidetector computed tomography (CT) for the assessment of perfusion defects (PDs), regional wall motion (RWM), and global left ventricular (LV) function., Materials and Methods: All myocardial infarction (MI) patients signed informed consent. The IRB approved the study and it was HIPAA-compliant. Cardiac multidetector CT was performed in 102 patients (34 with recent acute MI and 68 without). Multidetector CT images were analyzed for myocardial PD, RWM abnormalities, and LV function. Global LV function and RWM were compared with transthoracic echocardiography (TTE) by using multidetector CT. PD was detected by using multidetector CT and was correlated with cardiac biomarkers and single photon emission CT (SPECT) myocardial perfusion imaging. Multidetector CT diagnosis of acute MI was made on the basis of matching the presence of PD with RWM abnormalities compared with clinical evaluation., Results: Correlation between multidetector CT and TTE for global function (r = 0.68) and RWM (kappa = 0.79) was good. The size of PD on multidetector CT had a moderate correlation against SPECT (r = 0.48, -7% +/- 9). There was good to excellent correlation between cardiac biomarkers and the percentage infarct size by using multidetector CT (r = 0.82 for creatinine phosphokinase, r = 0.76 for creatinine phosphokinase of the muscle band, and r = 0.75 for troponin). For detection of acute MI in patients, multidetector CT sensitivity was 94% (32 of 34) and specificity was 97% (66 of 68). Multidetector CT had an excellent interobserver reliability for ejection fraction quantification (r = 0.83), as compared with TTE (r = 0.68)., Conclusion: Patients with acute MI can be identified by using multidetector CT on the basis of RWM abnormalities and PD.

Purpose: To prospectively compare 64-section multidetector computed tomography (CT) and cardiac magnetic resonance (MR) imaging for the early assessment of myocardial enhancement and infarct size after acute reperfused myocardial infarction (MI)., Materials and Methods: The study was HIPAA compliant and was approved by the institutional review board. All participants gave written informed consent. Twenty-one patients (18 men; mean age, 60 years +/- 13 [standard deviation]) were examined with 64-section multidetector CT and cardiac MR imaging 5 days or fewer after a first reperfused MI. Multidetector CT was performed during the first pass of contrast material to assess myocardial perfusion and detect microvascular obstruction (no reflow). In 15 patients, a second scan was performed 7 minutes later to assess total infarct size by using delayed hyperenhancement. Early hypoenhancement and delayed hyperenhancement were compared between multidetector CT and cardiac MR imaging with Pearson correlation coefficient and Bland-Altman analysis., Results: Early hypoenhancement was recognized on all multidetector CT and cardiac MR images. Delayed hyperenhancement was observed with cardiac MR imaging at all examinations and with multidetector CT at 11 of 15 examinations. While signal intensity differences between hypoperfused and normal myocardium were comparable for first-pass multidetector CT and cardiac MR imaging, cardiac MR imaging had a far better contrast-to-noise ratio (CNR) for delayed acquisitions than did CT (P < .001). Hypoenhanced areas (as a percentage of left ventricular mass) at first-pass multidetector CT (11% +/- 6) correlated well with those at first-pass cardiac MR imaging (7% +/- 4, R(2) = 0.72). Delayed-enhancement multidetector CT (13% +/- 9) correlated well with delayed-enhancement cardiac MR imaging (15% +/- 7, R(2) = 0.55). Quantification of delayed hypoenhancement (n = 12) had very good correlation between multidetector CT (4% +/- 4) and cardiac MR imaging (3% +/- 2) (R(2) = 0.85)., Conclusion: Early and late hypoenhancement showed good CNR and correlated well between multidetector CT and cardiac MR imaging.

Objective: To evaluate the efficacy of 64-slice coronary multidetector computed tomography (MDCT) in the assessment of congenital coronary artery fistula (CCAF)., Methods: Two readers prospectively evaluated the 64-slice coronary MDCT appearances of CCAF in 10 patients (5 men and 5 women; mean age, 58.6 years; range, 19-82 years). Fistula origin, course, distal entry site, and maximal receiving chamber/vessel dimensions were determined using retrospective multisegment reconstructions at 10% increments of the cardiac cycle., Results: Origin, course, and distal vessel entry site of CCAF were clearly outlined in all patients. The distal vessel draining site involved multiple small entry vessels in 5 patients and a single entry vessel in 5 patients. The right atrium in 3 patients and right ventricle in all patients were enlarged. Contrast opacification of the receiving chamber (contrast shunt sign) was detected in 4 patients, indicating patency and site of fistula entry., Conclusion: Cardiac 64-slice MDCT provides excellent visualization of the origin, course, and distal vessel entry site of CCAF and the size of the receiving chamber.

Background: Recent advances in 64-slice multidetector computed tomography (MDCT) provide an opportunity to assess coronary artery disease, left ventricular function and, potentially, valvular heart disease., Objective: To determine the ability of 64-MDCT to both detect and to quantify the severity of aortic regurgitation (AR), as compared with transthoracic echocardiography (TTE)., Methods: We evaluated a total of 64 patients (43 males, mean age 63+/-11 years), 30 with varying severities of AR as assessed by TTE and 34 matched controls. The severity of AR by TTE was determined using the vena contracta, the ratio of jet to left ventricular outflow tract (LVOT) height, and the ratio of the jet to LVOT cross-sectional area. AR by MDCT was defined as a lack of coaptation of the aortic valve leaflets in diastole and, if detected, the maximum anatomic aortic regurgitant orifice was determined., Results: All 34 control patients without AR were correctly identified by MDCT. There were 14 patients with mild AR, 10 with moderate AR, and 6 with severe AR by TTE. Of these patients, MDCT correctly identified 21 patients with AR (sensitivity 70%, specificity 100%, positive predictive value [PPV] 100%, and negative predictive value [NPV] 79%). Anatomic regurgitant orifice area measured by MDCT correlated well with the TTE-derived vena contracta (r=0.79, P<0.001), ratio of jet to LVOT height (r=0.79, P<0.001), and ratio of jet to LVOT cross-sectional area (r=0.75, P<0.001)., Conclusions: Direct planimetric measurement of the aortic valve anatomic regurgitant orifice area on 64-MDCT provides an accurate, noninvasive technique for detecting and quantifying AR.

Purpose: To retrospectively evaluate the diagnostic accuracy of multidetector computed tomography (CT) coronary angiography for detection of hemodynamically significant (>or=50%) stenoses by using various image postprocessing methods, with conventional coronary angiography as the reference standard., Materials and Methods: The analysis used data from previous studies, use of which had been approved by the Institutional Review Board. Sixteen-section multidetector CT data sets for 40 patients (30 men, 10 women; mean age 56 years +/- 8; mean heart rate, 61 beats per minute +/- 6) were evaluated. Six independent investigators evaluated the data sets for the presence of stenoses with diameter reduction of 50% or more, by using either exclusively transverse images, free oblique multiplanar reconstructions (MPRs), free oblique maximum intensity projections (MIPs, 5 mm thick), prerendered curved MPRs, prerendered curved MIPs, or prerendered three-dimensional volume rendered reconstructions (VRTs). Evaluation results were compared with conventional coronary angiography for each artery in a blinded fashion (chi(2) test)., Results: Overall, 35 coronary artery stenoses were present. Percentage of evaluable arteries and accuracy for detecting stenosis (percentages of accurately classified arteries were, respectively, 99% and 88% for transverse, 99% and 91% for oblique MPR, 94% and 86% for oblique MIP, 94% and 83% for curved MIP, 93% and 81% for curved MPR, and 91% and 73% for VRT). Accuracy was significantly higher for oblique MPR than for curved MPR (P=.01), curved MIP (P=.03), and VRT (P<.001)., Conclusion: The evaluation of multidetector CT coronary angiography with interactive image display methods, especially interactive oblique MPRs, permits higher diagnostic accuracy than evaluation of prerendered images (curved MPR, curved MIP, or VRT images)., ((c) RSNA, 2007.)

Background: Heart transplant recipients present a challenge to cardiac multi-detector computed tomography (MDCT) imaging due to high resting heart rates and body mass indices. Previous studies demonstrated the feasibility of coronary allograft vasculopathy detection by MDCT in heart transplant recipients. However, its performance in assessing cardiac structure and function in these patients has not been evaluated. The aim of this study was to compare 64-slice MDCT analysis of cardiac structure and function to 2-dimensional echocardiography in heart transplant recipients., Methods: Two independent observers used both semi-automated and automated software to measure chamber dimensions and left ventricular ejection fraction and mass in 20 heart transplant recipients by 64-slice MDCT. Inter-observer variability was determined. The results were compared with echocardiographic measurements provided by another blinded observer., Results: There was moderate agreement between MDCT and echocardiography for chamber dimension measurements, except for left atrial diameter. Ejection fraction by MDCT was slightly lower (mean difference: -2 +/- 9%, p = 0.29) than that obtained by echocardiography and the correlation was moderate (R = 0.49 to 0.54). Left ventricular mass measurements were significantly lower by MDCT (mean difference: -87 +/- 44 g, p < 0.001). Inter-observer agreement for MDCT analysis of left ventricular function (R = 0.90) and mass (R = 0.83) were excellent., Conclusions: These findings demonstrate moderate agreement between 64-slice MDCT and echocardiography in the assessment of chamber dimensions as well as left ventricular mass and function in heart transplant recipients with low inter-observer variability. Also, the addition of cardiac structural and functional analysis to MDCT coronary angiography requires no additional scan time, contrast administration or radiation exposure.

Although 64-slice multidetector coronary computed tomography angiography (CTA) has been reported to have excellent test characteristics for the detection of significant coronary artery disease, current analytic approaches may not appropriately reflect the process of clinical decision making. Thirty-seven patients (29 men; mean age 63 +/- 11 years) who underwent coronary CTA for clinical indications followed by invasive coronary angiography within 4 weeks were studied. Computed tomography angiograms were analyzed independently for the presence of significant coronary artery stenosis (>or=50% luminal narrowing) by 2 observers blinded to invasive coronary angiographic results. The diagnostic test performance of coronary CTA was determined with and without inclusion of unassessable segments. Because stenosis could not be excluded in unassessable segments, these segments were counted as positive for stenosis. Sensitivity, specificity, and positive (PPV) and negative predictive values of CTA for detecting significant stenoses on assessable segments were 85% (51 of 60, 95% confidence interval [CI] 76% to 94%), 99% (414 of 416, 95% CI 99 to 100), 96% (95% CI 51 of 53), and 98% (95% CI 414 of 423), respectively. Overall, 13% of coronary segments (70 of 546) were not assessable using CTA (heavy calcium in 48 segments). By including these segments, PPV decreased from 96% to 60% (74 of 123), whereas sensitivity improved from 85% to 89% (95% CI 74 of 83). In conclusion, the clinical utility of coronary CTA may be limited by a low PPV in patients with a high prevalence of coronary artery disease.

Background: The extent and nature of overall coronary artery disease (CAD), defined as the cumulative stenotic and nonstenotic, calcified and noncalcified atherosclerosis burden, are underestimated by invasive coronary angiography (ICA) and more accurately quantified with intravascular ultrasound. Multidetector row computed tomography (MDCT) is inferior to intravascular ultrasound but may constitute an attractive noninvasive alternative to assess overall CAD burden., Methods: To compare ICA with MDCT for detection of CAD (defined as luminal narrowing of any degree or calcification by ICA and any atherosclerotic plaque detection by MDCT using the 17-segment model), we studied 37 patients (age, 63 +/- 11 years) who underwent both tests., Results: A total of 508 of 586 (87%) segments were assessable, and CAD was detected in 121 of 508 (24%) segments by ICA versus 338 of 508 (67%) by MDCT (P < .01). Of the 121 segments positive for CAD by ICA, MDCT detected plaques in 117 segments (97%). In the 387 of 508 (76%) segments that were free of CAD by ICA, MDCT detected CAD in 221 (57%) segments. Overall, ICA detected CAD in only 20%, 48%, and 46% of segments with noncalcified, calcified, and mixed plaques, respectively, seen by MDCT (P = .01). Of the 221 segments negative for CAD by ICA, 119 (54%) were positively remodeled on MDCT. Overall correlation between ICA and MDCT for detection of CAD was poor (kappa = 0.25)., Conclusions: Invasive coronary angiography and MDCT differ significantly in estimating the presence and nature of CAD. Multidetector row computed tomography may provide an attractive noninvasive alternative to ICA to assess the effects of medical therapy.

Objective: The purpose of this pictorial essay is to review the 64-MDCT appearance of congenital anomalies of the origins of the coronary arteries in adults., Conclusion: Increasing use of MDCT for cardiac imaging of adults requires familiarity with the cross-sectional appearance of congenital coronary artery anomalies visualized with noninvasive imaging techniques. Many of these anomalies are benign, but a small number are associated with myocardial ischemia and sudden death. Increasing use of MDCT in cardiac imaging may yield diagnostic information not obtained with coronary angiography. Axial, multiplanar, and 3D volume-rendered reconstructions should aid in detection and improve interpretation of such anomalies.

Objective: The aortic valve can be assessed using MDCT; however, measurements of the aortic opening area vary with the cardiac cycle. In this study, we sought to assess the optimal timing for measuring the area of the aortic opening with MDCT., Materials and Methods: Retrospectively gated MDCT was performed in 57 patients with the following parameters: gantry rotation time, 420 milliseconds; tube voltage, 120 kV; tube current, 550 mAs with tube current modulation; and slice collimation, 16 x 0.75 mm. From 72 to 100 mL of contrast agent (320 g/mL3) was injected i.v. at 4-5 mL/s. High-resolution data sets were obtained for planimetry at phase starts of 0, 50, 100, 150, and 200 milliseconds after the R wave peak and were assessed for aortic opening area and the presence of artifacts., Results: In 41% of patients, the cardiac phase with the largest aortic opening area was at 50 milliseconds after the R wave peak. The area of the aortic opening measured at 0 milliseconds after the R peak was 2.7 +/- 0.8 cm2 (mean +/- SD); at 50 milliseconds, 2.9 +/- 0.2 cm2; at 100 milliseconds, 2.9 +/- 0.7 cm2; at 150 milliseconds, 2.8 +/- 0.7 cm2; and at 200 milliseconds, 2.4 +/- 0.8 cm2. The image quality was best at 50 milliseconds after the R peak in 42% of patients, 100 milliseconds in 29%, 150 milliseconds in 20%, 0 milliseconds in 7%, and 200 milliseconds in 2%. The aortic valve appeared closed in three patients at 0 milliseconds and in four patients at 200 milliseconds. Fewer artifacts were present in the midsystolic phases (i.e., 50-150 milliseconds) ("double-leaflet" artifact, 5-13%; "incomplete contour" artifact, 20-26%) than in the early (0 milliseconds) and late (200 milliseconds) systolic phases (double-leaflet artifact, 38% and 43% of patients; incomplete contour artifact, 76% and 73%, respectively)., Conclusion: Aortic valve planimetry is best performed at phase starts of 50-100 milliseconds after the R peak because the area of the aortic opening is widest and image quality is best at that phase.

Along with coronary evaluation, 64-slice multidetector computed tomography (MDCT) permits comprehensive assessment of left ventricular (LV) anatomy and function; however, how it compares with 2-dimensional transthoracic echocardiography (TTE) in patients with heart failure (HF) is not known. In this study, we compared 25 patients with ejection fractions of <45% who underwent TTE and MDCT. The global ejection fraction by TTE versus MDCT was 36 +/- 8% versus 38 +/- 12% (r = 0.67, p = NS). The mean LV end-diastolic and end-systolic diameters by TTE and MDCT were 56 +/- 8 and 46 +/- 9 mm and 58 +/- 12 and 47 +/- 11 mm, respectively (r = 0.71 and 0.77, respectively, both p >0.20). The mean lateral and septal wall thicknesses by TTE and MDCT were 10 +/- 1.4 and 11 +/- 1.5 mm and 10 +/- 1.3 and 10 +/- 1.4 mm (r = 0.77 and 0.76, respectively, both p >0.20). The mean LV end-diastolic and end-systolic volumes and stroke volume by TTE and MDCT were 123 +/- 45, 78 +/- 31, and 44 +/- 21 ml and 140 +/- 58, 92 +/- 43, and 48 +/- 24 ml, respectively (r = 0.62, 0.67, and 0.60, respectively, all p >0.20). The regional wall motion assessment correlation was good between the 2 modalities (kappa = 0.61). The interobserver correlation between the 2 MDCT readers ranged from good (r = 0.72 for LV end-diastolic volume) to excellent (r = 0.84 for septal wall thickness). In conclusion, MDCT provides comparable results to TTE for LV structure and functional assessment among patients with HF.

Unlabelled: Multi-detector row Computed Tomography (MDCT) permits non-invasive visualization of the coronary arteries. The ability to visualize and, with limitations, to characterize non-calcified coronary atherosclerotic plaque has been described. We investigated the CT attenuation of non-calcified plaques as determined by 16-slice MDCT in comparison to intravascular ultrasound (IVUS)., Methods and Results: Thirty-two patients were investigated by contrast-enhanced 16-slice CT. In addition, IVUS of one coronary artery (motorized pullback) was performed (LM+LAD: 22, LM+LCX: 4, RCA: 6). At 252 sites within the coronary system, in which non-calcified atherosclerotic plaque could be identified both in MDCT and IVUS, the CT attenuation within the plaque was measured using a centrally placed region of interest and correlated to the appearance of the plaque in IVUS at the corresponding location. The mean CT attenuation within plaque that corresponded to hyper-echogenic appearance in IVUS was 121+/-34HU (n=76). The mean CT attenuation within plaque that corresponded to hypo-echogenic appearance was 58+/-43HU (n=176, p<0.001). However, there was substantial overlap of the density values measured by MDCT in the two groups., Conclusions: A significant difference of the mean CT attenuation within atherosclerotic lesions of hypo-echogenic and hyper-echogenic appearance in IVUS could be observed. However, we observed substantial overlap of attenuation values between plaque types so that the differentiation of "vulnerable" and "stable" plaques based on their CT attenuation is doubtful.

Background: Noninvasive assessment of coronary atherosclerotic plaque and significant stenosis by coronary multidetector computed tomography (MDCT) may improve early and accurate triage of patients presenting with acute chest pain to the emergency department., Methods and Results: We conducted a blinded, prospective study in patients presenting with acute chest pain to the emergency department between May and July 2005 who were admitted to the hospital to rule out acute coronary syndrome (ACS) with no ischemic ECG changes and negative initial biomarkers. Contrast-enhanced 64-slice MDCT coronary angiography was performed immediately before admission, and data sets were evaluated for the presence of coronary atherosclerotic plaque and significant coronary artery stenosis. All providers were blinded to MDCT results. An expert panel, blinded to the MDCT data, determined the presence or absence of ACS on the basis of all data accrued during the index hospitalization and 5-month follow-up. Among 103 consecutive patients (40% female; mean age, 54+/-12 years), 14 patients had ACS. Both the absence of significant coronary artery stenosis (73 of 103 patients) and nonsignificant coronary atherosclerotic plaque (41 of 103 patients) accurately predicted the absence of ACS (negative predictive values, 100%). Multivariate logistic regression analyses demonstrated that adding the extent of plaque significantly improved the initial models containing only traditional risk factors or clinical estimates of the probability of ACS (c statistic, 0.73 to 0.89 and 0.61 to 0.86, respectively)., Conclusions: Noninvasive assessment of coronary artery disease by MDCT has good performance characteristics for ruling out ACS in subjects presenting with possible myocardial ischemia to the emergency department and may be useful for improving early triage.

Objective: Current risk stratification of patients with acute chest pain but normal initial cardiac enzymes and nondiagnostic ECG is inefficient. We sought to determine whether contrast-enhanced MDCT-based detection of stenosis is feasible and improves early and accurate triage of patients with acute chest pain., Subjects and Methods: We studied 40 patients (53% men; mean age, 57 +/- 13 years) with chest pain who were awaiting hospital admission to rule out an acute coronary syndrome (ACS) despite the absence of diagnostic ECG changes and normal cardiac enzymes on emergency department presentation. Patients underwent contrast-enhanced MDCT before hospital admission. Afterward, patients received standard clinical care. All physicians involved in the patients' care were blinded to the results of MDCT. An expert panel established the presence or absence of ACS based on American Heart Association (AHA) guidelines. The MDCT images were evaluated for the presence of significant coronary artery stenosis (diameter reduction > 50%) and were used to make a triage decision., Results: All five patients (12.5%) with ACS (one with non-ST elevation myocardial infarction, four with unstable angina pectoris) had at least one significant coronary stenosis on MDCT (sensitivity, 100% [95% CI, 49-100%)]. ACS was ruled out in 35 patients (87.5%). Significant coronary stenosis was excluded in 26 of the 35 patients without ACS by MDCT (specificity, 74% [CI, 75-88%]), potentially saving 70% of unnecessary hospital admissions., Conclusion: MDCT-based detection of significant coronary stenoses has tremendous potential to decrease the number of unnecessary hospital admissions, without reducing appropriate admission rates, in patients with chest pain who have nondiagnostic ECG results and normal cardiac enzymes. These results are likely to further improve with advances in MDCT technology.

Coronary allograft vasculopathy (CAV) is the most important limitation to long-term survival in adult heart transplant recipients and is difficult to detect without intravascular ultrasound (IVUS). We systematically evaluated the image quality of 64-slice multidetector computed tomographic (MDCT) coronary angiography in heart transplant recipients and tested the hypothesis that this modality is comparable to invasive coronary angiography with IVUS for the detection of CAV. Heart transplant recipients (n = 20) underwent invasive coronary angiography with IVUS and MDCT coronary angiography with a 64-slice scanner. Images were systematically analyzed for image quality and the presence of CAV. In addition, multidetector computed tomography and quantitative coronary angiography were used to measure lumen diameters at prespecified locations. Image quality analysis showed that, despite high mean heart rates (77 +/- 7 beats/min) and body mass index (29.5 +/- 5.3 kg/m(2)), 83% of coronary segments were graded as of excellent or good image quality. On average, 95 +/- 9% of the overall visualized length of the coronary arteries was imaged without motion artifacts, and the mean contrast-to-noise ratio was 11.3 +/- 4.6. Compared with IVUS, multidetector computed tomography had a sensitivity of 70%, specificity of 92%, positive predictive value of 89%, and negative predictive value of 77% for the detection of CAV. MDCT vessel diameter measurements correlated well with those obtained from quantitative coronary angiography (R(2) = 0.89). In conclusion, 64-slice multidetector computed tomography provides good to excellent image quality in heart transplant recipients and has moderate to excellent test characteristics for the detection of CAV. Further, MDCT measurements of lumen diameters correlated well with quantitative coronary angiography.

Purpose: To evaluate the diagnostic performance of 16-section multidetector computed tomography (CT) for assessment of plaques in phantoms and ex vivo coronary arteries, with intravascular ultrasonography (US) and optical coherence tomography (OCT) as reference standards., Materials and Methods: Research protocol was HIPAA compliant and approved by institutional review board, without informed consent required. Blood vessel and lesion composition phantoms and ex vivo coronary arteries were imaged with 16-section CT. Wall areas of phantoms and ex vivo coronary arteries were measured with multidetector CT and intravascular US. Sensitivity and specificity for lipid detection were determined in lesion composition phantoms. CT numbers of blood vessel wall were determined in ex vivo coronary arteries and compared with lesion classification results from OCT. Agreement in dimensional measurements was compared (paired t tests). CT numbers within blood vessel wall of CT cross sections classified as lipid rich, fibrous, and calcified at OCT were compared (Kruskal-Wallis tests)., Results: Mean blood vessel wall areas measured with CT and US in phantoms were 9.2 mm(2) +/- 1.8 (standard deviation) and 10.4 mm(2) +/- 3.4 (bias, -1.3 mm(2) +/- 3.1; P < .05), respectively. Mean blood vessel wall areas measured in ex vivo coronary arteries with CT and US were 10.9 mm(2) +/- 4.1 and 9.1 mm(2) +/- 3.1 (bias, 1.8 mm(2) +/- 3.0; P < .001), respectively. Sensitivity and specificity of 93% and 92%, respectively, for identification of lipid-rich lesions were observed in lesion composition phantoms. Mean CT numbers in blood vessel wall of ex vivo coronary arteries identified at OCT as predominantly lipid rich, fibrous, and calcified were 29 HU +/- 43, 101 HU +/- 21, and 135 HU +/- 199, respectively (P < .001)., Conclusion: Determination of composition of individual plaques from attenuation values can be more challenging because of overlapping values for different tissue types., ((c) RSNA, 2006.)

Clinical use of cardiac computed tomography is rapidly expanding, and its purpose may reach beyond noninvasive coronary angiography. We investigated the ability of 64-slice multidetector computed tomography to differentiate between recent and long-standing myocardial infarction (MI). Contrast-enhanced coronary computed tomographic (CT) scans (Siemens Sensation 64) of patients with a recent MI (< 7 days, n = 16), long-standing MI (> 12 months, n = 13), and no MI (n = 13) were retrospectively evaluated. To anticipate transmural variation of myocardial perfusion and to neutralize image noise, a series of thin, overlapping slices was created in parallel alignment to the myocardial wall. Within each of these slices, a small region of interest was placed at a constant in-plane position to measure the CT attenuation (Hounsfield units [HU]) at consecutive transmural locations of injured and normal remote myocardium. In addition, wall thickness and the myocardial cavity were measured. Significantly lower CT attenuation values were found in patients with long-standing MI (-13 +/- 37 HU) than in those with acute MI (26 +/- 26 HU) and normal controls (73 +/- 14 HU, p < 0.001). The attenuation difference between infarcted and remote myocardia was larger in patients with long-standing MI than in patients with recent MI (89 +/- 41 and 55 +/- 33 HU, respectively, p < 0.001). In addition, long-standing MI was associated with wall thinning (p < 0.01), and ventricular dilation (p < 0.05), whereas recent MI was not (p > 0.05). In conclusion, recent and long-standing MIs may be differentiated by computed tomography based on myocardial CT attenuation values and ventricular dimensions.

Current strategies for the triage of patients who have chest pain but normal initial cardiac enzyme levels and nondiagnostic electrocardiograms do not permit efficient risk stratification. The potentially fatal consequences and high malpractice costs of missed acute coronary syndromes lead every year to the unnecessary hospital admission of about 2.8 million patients who present with acute chest pain in emergency departments in the United States. Most of these patients are at very low risk for an acute coronary syndrome. However, the standard clinical work-up does not provide information about the presence and extent of coronary artery disease. In most patients (80%-94%) with an acute coronary syndrome, a significant coronary artery stenosis can be detected with selective coronary angiography. High levels of diagnostic accuracy also have been established for the detection of significant coronary artery stenosis with the use of 16- and 64-section multidetector computed tomography (CT) in patients with stable angina. Preliminary data indicate that multidetector CT also can help quantify and characterize coronary atherosclerotic plaque and that the CT findings are in good agreement with those at intravascular ultrasonography. Although multidetector CT provides accurate information about the presence of coronary artery disease, large blinded observational studies are warranted to identify CT characteristics with high accuracy for diagnosis of acute coronary syndromes. Such information would enable the conduct of randomized controlled trials to determine whether the detection of coronary stenosis and plaque with multidetector CT improves triage and reduces the costs or increases the cost-effectiveness of management of acute chest pain., (Copyright RSNA, 2006)