Optimizing Identification of Power Injectable Ports on the Scout Images for Multidetector Computed Tomography Procedures.

OBJECTIVE: The objective of this study was to assess the impact of tube voltage and image display on the identification of power ports features on anterior-posterior scout images to inform optimal workflow for multidetector computed tomography (MDCT) examinations. MATERIALS AND METHODS: Four ports, representing variable material composition (titanium/silicone), shapes, and computed tomography (CT) markings, were imaged on an adult anthropomorphic chest phantom using a dual-source MDCT at variable peak tube voltages (80, 100, 120, 150, and Sn150 kVp). Images were reviewed at variable image display setting by 5 blinded readers to assess port features of material composition, shape, and text markings as well as overall preferred image quality. RESULTS: Material composition was correctly identified for all ports by all readers across all kilovoltage-peak settings. The identification by shape was more reliable than CT markers for all but one of the ports. CT marker identification was up to 80% for titanium ports at window level settings optimized for metal (window width, 200; window center, -150) and at a soft tissue setting (window width, 400; window center, 40) for silicone ports. Interreader agreement for best image quality per kilovoltage-peak setting was moderate to substantial for 3 ports (k = 0.5-0.62) but only fair for 1 port (k = 0.27). The highest overall rank for image quality was given unanimously to Sn150 kVp for imaging titanium ports and 100 kVp for silicone ports. CONCLUSIONS: Power port identification on MDCT scout images can be optimized with modification of MDCT scout acquisition and display settings based on the main port material.

Correlation of preoperative imaging characteristics with donor outcomes and operative difficulty in laparoscopic donor nephrectomy.

This study aimed to understand the relationship of preoperative measurements and risk factors on operative time and outcomes of laparoscopic donor nephrectomy. Two hundred forty-two kidney donors between 2010 and 2017 were identified. Patients' demographic, anthropomorphic, and operative characteristics were abstracted from the electronic medical record. Glomerular filtration rates (GFR) were documented before surgery, within 24 hours, 6, 12, and 24 months after surgery. Standard radiological measures and kidney volumes, and subcutaneous and perinephric fat thicknesses were assessed by three radiologists. Data were analyzed using standard statistical measures. There was significant correlation between cranio-caudal and latero-lateral diameters (P < .0001) and kidney volume. The left kidney was transplanted in 92.6% of cases and the larger kidney in 69.2%. Kidney choice (smaller vs. larger) had no statistically significant impact on the rate of change of donor kidney function over time adjusting for age, sex and race (P = .61). Perinephric fat thickness (+4.08 minutes) and surgery after 2011 were significantly correlated with operative time (P ≤ .01). In conclusion, cranio-caudal diameters can be used as a surrogate measure for volume in the majority of donors. Size may not be a decisive factor for long-term donor kidney function. Perinephric fat around the donor kidney should be reported to facilitate operative planning.

Case 274: Cardiac Echinococcus.

HistoryA 47-year-old Sudanese man without a known remarkable medical history presented to the emergency department for a syncopal episode. The patient denied chest pain, dyspnea, focal weakness, or prior similar episodes. He was originally from north Sudan and eventually moved to Saudi Arabia, where he worked as a farm manager before emigrating to the United States years ago. Physical examination findings and routine laboratory values, including complete blood count and basic metabolic panels, were normal. Electrocardiography revealed nonspecific T-wave inversions, and a series of cardiac biomarkers were negative. A contrast material-enhanced CT angiography pulmonary embolism protocol and cardiac MRI were performed for further evaluation.

Preprocedural computed tomography before cardiac implanted electronic device lead extraction: Indication, technique, and approach to interpretation.

Cardiac implantable electronic devices (CIEDs) frequently need to be extracted due to infection, hardware failure, and other causes. The extraction of the CIED is typically performed using percutaneous methods. While these procedures are mostly performed without incident there is a small risk of significant complications. Dedicated imaging pre-CEID removal to include the central veins and heart with multidetector computed tomography (MDCT) can be utilized to evaluate the lead course and termination, the integrity of the central veins and cardiac chambers, and identify potential complications that may alter the lead extraction procedure as well as reimplantation of subsequent leads. Indications for preprocedural imaging, the technique of dedicated preprocedural lead extraction MDCT, and the approach to the interpretation of the images is discussed in this review.

Case 274.

History A 47-year-old Sudanese man without a known remarkable medical history presented to the emergency department for a syncopal episode. The patient denied chest pain, dyspnea, focal weakness, or prior similar episodes. He was originally from north Sudan and eventually moved to Saudi Arabia, where he worked as a farm manager before emigrating to the United States years ago. Physical examination findings and routine laboratory values, including complete blood count and basic metabolic panels, were normal. Electrocardiography revealed nonspecific T-wave inversions, and a series of cardiac biomarkers were negative. A contrast material-enhanced CT angiography pulmonary embolism protocol and cardiac MRI were performed for further evaluation (Figs 1-4). [Figure: see text] [Figure: see text] [Figure: see text] [Figure: see text] [Figure: see text] [Figure: see text].

Clinical Impact of Coronary Computed Tomography Angiography-Derived Fractional Flow Reserve on Japanese Population in the ADVANCE Registry.

BACKGROUND: Coronary computed tomography angiography (cCTA)-derived fractional flow reserve (FFRCT) is a promising diagnostic method for the evaluation of coronary artery disease (CAD). However, clinical data regarding FFRCTin Japan are scarce, so we assessed the clinical impact of using FFRCTin a Japanese population.Methods and Results:The ADVANCE registry is an international prospective FFRCTregistry of patients suspected of CAD. Of 5,083 patients, 1,829 subjects enrolled from Japan were analyzed. Demographics, symptoms, cCTA, FFRCT, treatment strategy, and 90-day major cardiovascular events (MACE) were assessed. Reclassification of treatment strategy between cCTA alone and cCTA+FFRCToccurred in 55.8% of site investigations and in 56.9% in the core laboratory analysis. Patients with positive FFR (FFRCT≤0.80) were less likely to have non-obstructive disease on invasive coronary angiography than patients with negative FFR (FFRCT>0.80) (20.5% vs. 46.1%, P=0.0001). After FFRCT, 67.0% of patients with positive results underwent revascularization, whereas 96.1% of patients with negative FFRCTwere medically treated. MACE occurred in 5 patients with positive FFRCT, but none occurred in patients with negative FFRCTwithin 90 days. CONCLUSIONS: In this Japanese population, FFRCTmodified the treatment strategy in more than half of the patients. FFRCTshowed potential for stratifying patients suspected of CAD properly into invasive or non-invasive management pathways.

Real-world clinical utility and impact on clinical decision-making of coronary computed tomography angiography-derived fractional flow reserve: lessons from the ADVANCE Registry.

Aims: Non-invasive assessment of stable chest pain patients is a critical determinant of resource utilization and clinical outcomes. Increasingly coronary computed tomography angiography (CCTA) with selective CCTA-derived fractional flow reserve (FFRCT) is being used. The ADVANCE Registry, is a large prospective examination of using a CCTA and FFRCT diagnostic pathway in real-world settings, with the aim of determining the impact of this pathway on decision-making, downstream invasive coronary angiography (ICA), revascularization, and major adverse cardiovascular events (MACE). Methods and results: A total of 5083 patients with symptoms concerning for coronary artery disease (CAD) and atherosclerosis on CCTA were enrolled at 38 international sites from 15 July 2015 to 20 October 2017. Demographics, symptom status, CCTA and FFRCT findings, treatment plans, and 90 days outcomes were recorded. The primary endpoint of reclassification between core lab CCTA alone and CCTA plus FFRCT-based management plans occurred in 66.9% [confidence interval (CI): 64.8-67.6] of patients. Non-obstructive coronary disease was significantly lower in ICA patients with FFRCT ≤0.80 (14.4%) compared to patients with FFRCT >0.80 (43.8%, odds ratio 0.19, CI: 0.15-0.25, P < 0.001). In total, 72.3% of subjects undergoing ICA with FFRCT ≤0.80 were revascularized. No death/myocardial infarction (MI) occurred within 90 days in patients with FFRCT >0.80 (n = 1529), whereas 19 (0.6%) MACE [hazard ratio (HR) 19.75, CI: 1.19-326, P = 0.0008] and 14 (0.3%) death/MI (HR 14.68, CI 0.88-246, P = 0.039) occurred in subjects with an FFRCT ≤0.80. Conclusions: In a large international multicentre population, FFRCT modified treatment recommendation in two-thirds of subjects as compared to CCTA alone, was associated with less negative ICA, predicted revascularization, and identified subjects at low risk of adverse events through 90 days.

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

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

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

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

Trans-lesional fractional flow reserve gradient as derived from coronary CT improves patient management: ADVANCE registry.

BACKGROUND: The role of change in fractional flow reserve derived from CT (FFRCT) across coronary stenoses (ΔFFRCT) in guiding downstream testing in patients with stable coronary artery disease (CAD) is unknown. OBJECTIVES: To investigate the incremental value of ΔFFRCT in predicting early revascularization and improving efficiency of catheter laboratory utilization. MATERIALS: Patients with CAD on coronary CT angiography (CCTA) were enrolled in an international multicenter registry. Stenosis severity was assessed as per CAD-Reporting and Data System (CAD-RADS), and lesion-specific FFRCT was measured 2 â€‹cm distal to stenosis. ΔFFRCT was manually measured as the difference of FFRCT across visible stenosis. RESULTS: Of 4730 patients (66 â€‹± â€‹10 years; 34% female), 42.7% underwent ICA and 24.7% underwent early revascularization. ΔFFRCT remained an independent predictor for early revascularization (odds ratio per 0.05 increase [95% confidence interval], 1.31 [1.26-1.35]; p â€‹< â€‹0.001) after adjusting for risk factors, stenosis features, and lesion-specific FFRCT. Among the 3 models (model 1: risk factors â€‹+ â€‹stenosis type and location â€‹+ â€‹CAD-RADS; model 2: model 1 â€‹+ â€‹FFRCT; model 3: model 2 â€‹+ â€‹ΔFFRCT), model 3 improved discrimination compared to model 2 (area under the curve, 0.87 [0.86-0.88] vs 0.85 [0.84-0.86]; p â€‹< â€‹0.001), with the greatest incremental value for FFRCT 0.71-0.80. ΔFFRCT of 0.13 was the optimal cut-off as determined by the Youden index. In patients with CAD-RADS ≥3 and lesion-specific FFRCT ≤0.8, a diagnostic strategy incorporating ΔFFRCT >0.13, would potentially reduce ICA by 32.2% (1638-1110, p â€‹< â€‹0.001) and improve the revascularization to ICA ratio from 65.2% to 73.1%. CONCLUSIONS: ΔFFRCT improves the discrimination of patients who underwent early revascularization compared to a standard diagnostic strategy of CCTA with FFRCT, particularly for those with FFRCT 0.71-0.80. ΔFFRCT has the potential to aid decision-making for ICA referral and improve efficiency of catheter laboratory utilization.

ACR Appropriateness Criteria® Chronic Chest Pain-High Probability of Coronary Artery Disease: 2021 Update.

Management of patients with chronic chest pain in the setting of high probability of coronary artery disease (CAD) relies heavily on imaging for determining or excluding presence and severity of myocardial ischemia, hibernation, scarring, and/or the presence, site, and severity of obstructive coronary lesions, as well as course of management and long-term prognosis. In patients with no known ischemic heart disease, imaging is valuable in determining and documenting the presence, extent, and severity of obstructive coronary narrowing and presence of myocardial ischemia. In patients with known ischemic heart disease, imaging findings are important in determining the management of patients with chronic myocardial ischemia and can serve as a decision-making tool for medical therapy, angioplasty, stenting, or surgery. This document summarizes the recent growing body of evidence on various imaging tests and makes recommendations for imaging based on the available data and expert opinion. This document is focused on epicardial CAD and does not discuss the microvascular disease as the cause for CAD. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Coronary volume to left ventricular mass ratio in patients with diabetes mellitus.

BACKGROUND: Diabetes mellitus is a major risk factor for coronary artery disease (CAD) and may provoke structural and functional changes in coronary vasculature. The coronary volume to left ventricular mass (V/M) ratio is a new anatomical parameter capable of revealing a potential physiological imbalance between coronary vasculature and myocardial mass. The aim of this study was to examine the V/M derived from coronary computed tomography angiography (CCTA) in patients with diabetes. METHODS: Patients with clinically suspected CAD enrolled in the ADVANCE (Assessing Diagnostic Value of Non-invasive FFRCT in Coronary Care) registry and known diabetic status were included. Coronary artery volume and left ventricular myocardial mass were analyzed from CCTA and the V/M ratio was calculated and compared between patients with and without diabetes. RESULTS: Of the 3053 patients (age 66 â€‹± â€‹10 years; 66% male) with known diabetic status, diabetes was present in 21.9%. Coronary volume was lower in patients with diabetes compared to those without diabetes (2850 â€‹± â€‹940 â€‹mm3 vs. 3040 â€‹± â€‹970 â€‹mm3, p â€‹< â€‹0.0001), whereas the myocardial mass was comparable between the 2 groups (122 â€‹± â€‹33 â€‹g vs. 122 â€‹± â€‹32 â€‹g, p â€‹= â€‹0.70). The V/M ratio was significantly lower in patients with diabetes (23.9 â€‹± â€‹6.8 â€‹mm3/g vs. 25.7 â€‹± â€‹7.5 â€‹mm3/g, p â€‹< â€‹0.0001). Among subjects with obstructive CAD (n â€‹= â€‹2191, 24.0% diabetics) and non-obstructive CAD (16.7% diabetics), the V/M ratio was significantly lower in patients with diabetes compared to those without (23.4 â€‹± â€‹6.7 â€‹mm3/g vs. 25.0 â€‹± â€‹7.3 â€‹mm3/g, p â€‹< â€‹0.0001 and 25.6 â€‹± â€‹6.9 â€‹mm3/g vs. 27.3 â€‹± â€‹7.6 â€‹mm3/g, respectively, p â€‹= â€‹0.006). CONCLUSION: The V/M ratio was significantly lower in patients with diabetes compared to non-diabetics, even after correcting for obstructive coronary stenosis. The clinical value of the reduced V/M ratio in diabetic patients needs further investigation.

Temporal changes in FFRCT-Guided Management of Coronary Artery Disease - Lessons from the ADVANCE Registry.

BACKGROUND: The ADVANCE registry is a large prospective study of outcomes and resource utilization in patients undergoing coronary computed tomography angiography (CCTA) and CT-based fractional flow reserve (FFRCT). As experience with new technologies and practices develops over time, we investigated temporal changes in the use of FFRCT within the ADVANCE registry. METHODS: 5083 patients with coronary artery disease (CAD) on CCTA were prospectively enrolled in the ADVANCE registry and were divided into 3 equally sized cohorts based on the temporal order of enrollment per site. Demographics, CCTA and FFRCT findings, and clinical outcomes through 1-year follow-up, were recorded and compared between tertiles. RESULTS: The number of patients with a ≥70% stenosis on CCTA was similar over time (33.6%, 30.9%, and 33.8% for cohort 1-3). The rate of positive FFRCT ≤0.80 was higher for cohorts 2 (67.3%) and 3 (74.6%) than for cohort 1 (57.1%, p < 0.001). Invasive FFR rates decreased from 25.8% to 22.4% between cohort 1 and 3 (p = 0.023). Moreover, patients with a FFRCT ≤0.80 were less frequently referred for invasive coronary angiography (ICA) (from 62.9% to 52.9%, p < 0.001), and underwent fewer revascularizations between cohort 1 and 3 (from 41.9% to 32.0%, p < 0.001). The prevalence of major events was low (1.2%) and similar between cohorts. CONCLUSIONS: Growing experience with FFRCT improved the likelihood of identifying hemodynamically significant CAD and safely reduced the need for ICA and revascularization in patients with anatomically significant disease even in the instance of an abnormal FFRCT.

ACR Appropriateness Criteria® Asymptomatic Patient at Risk for Coronary Artery Disease: 2021 Update.

Coronary atherosclerotic disease is a leading cause of mortality and morbidity due to major cardiovascular events in the United States and abroad. Risk stratification and early preventive measures can reduce major cardiovascular events given the long latent asymptomatic period. Imaging tests can detect subclinical coronary atherosclerosis and aid initiation of targeted preventative efforts based on patient risk. A summary of available imaging tests for low-, intermediate-, and high-risk asymptomatic patients is outlined in this document. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Syncope.

Syncope and presyncope lead to well over one million emergency room visits in the United States each year. Elucidating the cause of syncope or presyncope, which are grouped together given similar etiologies and outcomes, can be exceedingly difficult given the diverse etiologies. This becomes more challenging as some causes, such as vasovagal syncope, are relatively innocuous while others, such as cardiac-related syncope, carry a significant increased risk of death. While the mainstay of syncope and presyncope assessment is a detailed history and physical examination, imaging can play a role in certain situations. In patients where a cardiovascular etiology is suspected based on the appropriate history, physical examination, and ECG findings, resting transthoracic echocardiography is usually considered appropriate for the initial imaging. While no imaging studies are considered usually appropriate when there is a low probability of cardiac or neurologic pathology, chest radiography may be appropriate in certain clinical situations. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Infective Endocarditis.

Infective endocarditis can involve a normal, abnormal, or prosthetic cardiac valve. The diagnosis is typically made clinically with persistently positive blood cultures, characteristic signs and symptoms, and echocardiographic evidence of valvular vegetations or valvular complications such as abscess, dehiscence, or new regurgitation. Imaging plays an important role in the initial diagnosis of infective endocarditis, identifying complications, prognostication, and informing the next steps in therapy. This document outlines the initial imaging appropriateness of a patient with suspected infective endocarditis and for additional imaging in a patient with known or suspected infective endocarditis. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Suspected Acute Aortic Syndrome.

Acute aortic syndrome (AAS) includes the entities of acute aortic dissection, intramural hematoma, and penetrating atherosclerotic ulcer. AAS typically presents with sudden onset of severe, tearing, anterior, or interscapular back pain. Symptoms may be dominated by malperfusion syndrome, due to obstruction of the lumen of the aorta and/or a side branch when the intimal and medial layers are separated. Timely diagnosis of AAS is crucial to permit prompt management; for example, early mortality rates are reported to be 1% to 2% per hour after the onset of symptoms for untreated ascending aortic dissection. The appropriateness assigned to each imaging procedure was based on the ability to obtain key information that is used to plan open surgical, endovascular, or medical therapy. This includes, but is not limited to, confirming the presence of AAS; classification; characterization of entry and reentry sites; false lumen patency; and branch vessel compromise. Using this approach, CT, CTA, and MRA are all considered usually appropriate in the initial evaluation of AAS if those procedures include intravenous contrast administration. Ultrasound is also considered usually appropriate if the acquisition is via a transesophageal approach. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

The clinical utility of FFRCT stratified by age.

BACKGROUND: CT coronary angiography (CTA) with Fractional Flow Reserve as determined by CT (FFRCT) is a safe alternative to invasive coronary angiography. A negative FFRCT has been shown to have low cardiac event rates compared to those with a positive FFRCT. However, the clinical utility of FFRCT according to age is not known. METHODS: Patients' in the ADVANCE (Assessing Diagnostic Value of Non-invasive FFRCT in Coronary Care) registry, were stratified into those ≥65 or <65 years of age. The impact of FFRCT on clinical decision-making, as assessed by patient age, was determined by evaluating patient management using CTA results alone, followed by site investigators submitting a report on the treatment plan based upon the newly provided FFRCT data. Outcomes at 1-year post CTA were assessed, including major adverse cardiovascular events (myocardial infarction, all-cause mortality or unplanned hospitalization for ACS leading to revascularisation) and total revascularisation. Positive FFRCT was deemed to be â€‹≤ â€‹0.8. RESULTS: FFRCT was calculated in 1849 (40.6%) subjects aged <65 and 2704 (59.4%) â€‹≥ â€‹65 years of age. Subjects ≥65 years were more likely to have anatomic obstructive disease on CTA (≥50% stenosis), compared to those aged <65 (69.7% and 73.2% respectively, p â€‹= â€‹0.008). There was a similar graded increase in recommended and actual revascularisation with either CABG or PCI, with declining FFRCT strata for subjects above and below the age of 65. MACE and revascularisation rates were not significantly different for those â€‹≥ â€‹or <65, regardless of FFRCT positivity or stenosis severity <50% or ≥50%. With a negative FFRCT result, and anatomical stenosis ≥50%, those â€‹≥ â€‹and <65 years of age, had similar rates of MACE (0.2% for both, p â€‹= â€‹0.1) and revascularisation (8.7% and 10.4% respectively p â€‹= â€‹0.4). Logistic regression analysis, with age as a continuous variable, and adjustment for Diamond Forrester Risk, baseline FFRCT and treatment (CABG, PCI, medical therapy), indicated a statistically significant, but small increase in the odds of a MACE event with increasing age (OR 1.04, 95% CI 1.006-1.08, p â€‹= â€‹0.02). Amongst patients with a FFRCT > 0.80, there was no effect of age on the odds of revascularisation. CONCLUSION: The findings of this study point to a low risk of MACE events or need for revascularisation in those aged â€‹≥ â€‹or <65 with a FFRCT>0.80, despite the higher incidence of anatomic obstructive CAD in those ≥65 years. The findings show the clinical usefulness and outcomes of FFRCT are largely constant regardless of age.