Relationship of the Duke jeopardy score combined with minimal lumen diameter as assessed by computed tomography angiography to the hemodynamic relevance of coronary artery stenosis

ObjectivesTo study the diagnostic performance of the ratio between the Duke jeopardy score (DJS) and the minimal lumen diameter (MLD) (DJS/MLDCT ratio) as assessed by coronary computed tomographic angiography (CTA) for differentiating functionally significant from non-significant coronary artery stenoses, with reference to invasive fractional flow reserve (FFR).MethodsPatients who underwent both coronary CTA and FFR measurement during invasive coronary angiography (ICA) within 2 weeks were retrospectively included in the study. Invasive FFR measurement was performed in patients with intermediate to severe coronary stenoseis. DJS/MLDCT ratio and anatomical parameters were recorded. Lesions with FFR ≤0.80 were considered to be functionally significant.ResultsOne hundred and sixty-one patients with 175 lesions were included into the analysis. Diameter stenosis in CT, area stenosis, plaque burden, lesion length (LL), ICA-based stenosis degree, DJS, LL/MLD⁴ ratio, DJS/MLA ratio as well as DJS/MLD ratio were all significantly different between hemodynamically significant and non-significant lesions (p<0.05 for all). ROC curve analysis determined the optimal cut-off value for DJS/MLD_CT ratio to be 1.96 (area under curve = 0.863, 95 % confidence interval = 0.803–0.910), yielding a high diagnostic accuracy (86.9%, 152/175).ConclusionsIn coronary artery stenoses detected by coronary CTA, the DJS/MLD ratio is able to predict hemodynamic relevance.     

CT-based total vessel plaque analyses improves prediction of hemodynamic significance lesions as assessed by fractional flow reserve in patients with stable angina pectoris

BackgroundCoronary stenosis and plaque evaluation by coronary computed tomography angiography (CTA) may contribute to identify hemodynamically relevant lesions. We evaluated the most stenotic lesion including plaques proximal to it versus a total vessel analyses combined with stenosis for ischemia.MethodsPatients scheduled for clinically indicated invasive coronary angiography (ICA) for suspected coronary artery disease underwent coronary CTA and ICA including fractional flow reserve (FFR) as part of the NXT trial (clinicaltrials.gov NCT01757678). Stenoses were visually graded ≤50%, 51–70%, and >70% on coronary CTA. Semi-automated plaque analyses were performed using a proximal to the FFR pressure sensor location (including the most severe lesion to the coronary ostium) versus a total vessel (vessel diameter ≥2 mm) approach. Coronary stenosis and plaque parameters were evaluated for discrimination of ischemia by logistic regressions and combined models analyzed using receiver operating characteristics (ROC) with invasive FFR≤ 0.80 as reference standard.ResultsIn 254 patients, mean (±SD) age 64 (±10) years, 64% male, a coronary CTA stenosis >50% was present in 239 (49%) vessels. Invasive FFR was ≤0.80 in 100 (21%) vessels. Coronary stenosis severity and low-density non-calcified plaque (LD-NCP) volume were independent predictors of ischemia in the “proximal” and “total-vessel” analyses. Stenosis severity + total vessel LD-NCP assessment performed better than stenosis severity + proximal LD-NCP evaluation (Area under curve [AUC] (95%CI): 0.83 (0.78–0.87) vs 0.81 (0.76–0.86), p-value = 0.009), whereas stenosis severity + proximal LD-NCP performed better than stenosis alone (AUC (95%CI): 0.81 (0.76–0.86) vs 0.78 (0.73–0.83), p-value = 0.019).ConclusionAdding total vessel high-risk plaque volume to stenosis severity improves discrimination of ischemia in coronary CTA performed in patients with stable angina pectoris.     

Coronary plaque characteristics in computed tomography and 2-year outcomes: The PREDICT study

BackgroundCoronary computed tomography angiography (CCTA) not only provides information regarding luminal stenoses but also allows for visualization of mural atheromatous changes (coronary plaques).ObjectiveWe sought to elucidate whether plaques seen on CCTA enable prediction of 2-year outcomes in patients with suspected and known coronary artery disease (CAD).MethodsOf 3015 patients who underwent CCTA, the images and 2-year clinical courses of 2802 patients were independently analyzed. The primary endpoint was the composite of all-cause death and acute coronary syndrome.ResultsDuring the 2-year observation period, 49 (1.7%) patients developed the primary outcome. The 2-year rates of the primary outcome in the normal (n = 515, no mural lesions), calcium (n = 654, calcified lesion alone), and plaque groups (n = 1633, presence of noncalcified or partially calcified plaques) were 0.2%, 2.0%, and 2.1%, respectively (P = 0.0028). Adverse plaque features such as low attenuation, positive remodeling, spotty calcification, and the napkin-ring sign (low-attenuation core with a higher-attenuation rim) were assessed by an independent core laboratory. Stepwise multivariate Cox proportional hazard analysis showed that a plaque with two or more characteristics (adjusted hazard ratio, 1.98; 95% confidence interval, 1.09–3.60; P = 0.0254), age of ≥67 years (mean), statin treatment after CCTA, and obstructive stenosis remained independent predictors of the primary outcome.ConclusionsPlaque imaging in CCTA has predictive value for the 2-year outcome and is a useful identifier for high-risk patients among those with known and suspected CAD.     

Effect of low tube kV on radiation dose and image quality in retrospective ECG-gated coronary CT angiography

IntroductionCoronary computed tomography angiography (CCTA) has emerged as a useful diagnostic imaging modality in the assessment of coronary artery disease. However, the potential risks due to exposure to ionizing radiation associated with CCTA have raised concerns.ObjectivesCCTA can be done with low dose technique to reduce radiation exposure, without compromise of image quality or diagnostic capabilities.Material and methodsForty patients referred for CCTA were examined with low kV (100 kV for patients ?85–61 kg and 80 kV for patients ?60 kg). The dose length product (DLP) were compared with other group (40 patients) with comparable body weight, scan length and acquisition parameters. The second group was selected from PACS database, for which CCTA was done with standard 120 kV.ResultsThere was considerable reduction of radiation dose about 40% with 100 kV and 60% with 80 kV compared to standard 120 kV CCTA protocols with preserved image quality.ConclusionThe use of lower tube voltage leads to significant reduction in radiation exposure in CCTA. Image quality in non-obese patients is not negatively influenced.     

Dual-source CT coronary angiography: Diagnostic accuracy without the use of B blockers

PurposeTo evaluate the effect of heart rate, heart rate variability on dual-source computed tomography image quality performed without the use of B blockers and to assess diagnostic accuracy of dual-source CT (using adaptive electrocardiographic pulsing) for coronary artery stenosis, by using invasive coronary angiography as the reference standard.Materials and methodsPatients were studied without β-blocker pre-medication. Unenhanced CT and CT coronary angiography with adaptive ECG pulsing were performed using DSCT (DEFINITION, Siemens Medical Solutions, Forchheim, Germany). A contrast-enhanced volume dataset was acquired (two tubes, 120 kV, 400 mAs/rot, collimation 64 × 0.6 mm). Fifty-one patients (11 women, 40 men; mean age, 60.5 years ± 10 [standard deviation]) known to have or suspected of having coronary artery disease underwent dual-source CT and invasive coronary angiography. Accuracy of dual-source CT in depiction or exclusion of significant stenosis (?50%) was evaluated on a per-segment and per-patient basis. Effects of heart rate, heart rate variability were assessed. Patients were divided in three HRF groups: low, intermediate, and high (?65, 66–79, and ?80 beats/min, respectively), and four HRV groups given mean inter beat difference (IBD) during CT coronary angiography: normal, minor, moderate, and severe (IBDs of 0–1, 2–3, 4–10, and >10, respectively). The diagnostic performance was presented as sensitivity, specificity, positive predictive values, and negative predictive values validated against invasive coronary angiography (?50% lumen diameter reduction).ResultsGood image quality was achieved in 98% of patients without the use of B blockers and no significant differences in image quality were found among HRF and HRV groups. Twenty-three patients were examined having a heart rate ?65 beats/min, image quality was sufficient for diagnosis in 281 of 312 coronary segments (92%), whereas in 28 patients with a heart rate <65 beats/min, the image quality was sufficient for diagnosis in 387 of 388 coronary segments (100%). On a per-patient basis, 93% of patients (?65 beats/min) and 100% of patients (<65 beats/min) were considered evaluable. None of these differences were statistically significant. Similarly, no difference in diagnostic accuracy was found in per-vessel and -segment analyses.ConclusionIn 51 patients studied without β-blocker pre-medication, the overall image quality of dual-source CT coronary angiography is sufficient for diagnosis within a wide range of mean heart rates and variability of heart rates. Only heart rates that are both high and variable significantly deteriorate image quality, but the quality remains adequate for diagnosis.     

Machine learning in cardiac CT: Basic concepts and contemporary data

Propelled by the synergy of the groundbreaking advancements in the ability to analyze high-dimensional datasets and the increasing availability of imaging and clinical data, machine learning (ML) is poised to transform the practice of cardiovascular medicine. Owing to the growing body of literature validating both the diagnostic performance as well as the prognostic implications of anatomic and physiologic findings, coronary computed tomography angiography (CCTA) is now a well-established non-invasive modality for the assessment of cardiovascular disease. ML has been increasingly utilized to optimize performance as well as extract data from CCTA as well as non-contrast enhanced cardiac CT scans. The purpose of this review is to describe the contemporary state of ML based algorithms applied to cardiac CT, as well as to provide clinicians with an understanding of its benefits and associated limitations.     

Optimized energy of spectral coronary CT angiography for coronary plaque detection and quantification

BackgroundTo optimize spectral coronary computed tomography angiography (CTA) for quantification of coronary artery plaque components.Materials and methodsFifty-one subjects were prospectively enrolled (88.2% male) (NCT02740699). Dual energy coronary CTA was performed at 90/Sn150 kVp using a 3rd generation dual-source CT scanner (SOMATOM Force, Siemens Healthcare). Dual energy images were reconstructed with a) linear mixed blending of 90 and Sn150 kVp data, b) virtual monoenergetic algorithm from 40 to 150 keV (at 10- keV intervals), and c) noise-optimized virtual monoenergetic algorithm from 40 to 150 keV. Image noise, iodine signal-to-noise-ratio (SNR), and contrast-to-noise ratio (CNR) for calcified and non-calcified plaque were measured. Qualitative readings of image quality were performed. Semi-automated software (QAngioCT, Medis) was used to quantify coronary plaque. Linear mixed-models that account for within-subject correlation of plaques were used to compare the results.Results100–150 keV noise-optimized virtual monoenergetic images had lower image noise than linear mixed images (all P < 0.05). The highest iodine SNR was achieved in 40 keV noise-optimized virtual monoenergetic images (33.3 ± 0.6 vs 23.3 ± 0.7 for linear mixed images, P < 0.001). 40–70 keV noise-optimized virtual monoenergetic images and 70 keV virtual monoenergetic images had superior coronary plaque CNR versus linear mixed images (all P < 0.01) with a maximum improvement of 20.1% and 22.7% for calcified plaque and non-calcified plaque (38.8 ± 2.2 vs 32.3 ± 2.3 and 17.3 ± 1.3 vs 14.1 ± 1.4, respectively). Using 90/Sn150 kVp linear mixed images as a reference, the plaque quantity was similar for 70 keV noise-optimized virtual monoenergetic images whereas low keV images (e.g. 40 keV) yielded significantly higher coronary plaque volumes (all P < 0.001).ConclusionSpectral coronary CTA with low energy (40–70 keV) post-processing can improve the CNR of coronary plaque components. However, low energies (such as 40 keV) resulted in different absolute volumes of coronary plaque compared to “conventional” mixed 90/Sn150 kVp images.     

Value of multislice CT coronary arteries calcification scoring in the prediction of coronary arteries pathology in chronic kidney disease patients

PurposeTo determine the value of multislice CT coronary artery calcification (CAC) scoring in the prediction of future cardiac events in known chronic kidney disease (CKD) patients using conventional coronary angiography as the standard reference.Patients and methodsFifty-eight patients with CKD on hemodialysis underwent CT CAC scoring using multislice scanner and conventional coronary angiography. Results of CAC scoring were compared to the findings of conventional coronary angiography.ResultsMean CAC scoring in patients with significant coronary arteries stenotic lesions was higher than in patients with no significant coronary arteries stenotic lesions with significant difference (P < 0.001).Mean patient CAC scoring was strongly correlated with the number of coronary arteries with significant stenotic lesions (r = 0.910).ConclusionCT CAC scoring is a non-invasive technique which can be used in the evaluation and follow up of CKD patients’ coronary arteries without the use of contrast medium reducing the number of invasive coronary angiography needed.     

Dynamic Volumetric CT Angiography for the Detection and Classification of Endoleaks: Application of Cine Imaging Using a 320-Row CT Scanner with 16-cm Detectors

PurposeTo assess the feasibility and diagnostic performance of dynamic volumetric computed tomography (CT) angiography with large-area detectors in the detection and classification of endoleaks after endovascular aneurysm repair (EVAR).Materials and MethodsLow-dose dynamic volumetric CT angiography performed with the patient in Fowler position was used to scan the entire stent graft with a 16-cm-area detector during the first follow-up examination after EVAR. There were 39 consecutive patients (36 men and 3 women; mean age, 74 y ± 8.7) examined with approximately 14–20 intermittent scans (temporal resolution, 2 s; scan range, 160 mm). The effective radiation dose, image quality, interobserver and intraobserver agreement for endoleak detection, and time delay between peak enhancement of the aorta and endoleaks were evaluated.ResultsAll examinations with the patient in Fowler position enabled the entire stent graft to be scanned and were rated as diagnostic. The mean effective radiation dose was 13.1 mSv. Endoleaks were detected in eight patients (type Ia, n = 1; type II, n = 6; type III, n = 1). Interobserver agreement (κ = 0.794) and intraobserver agreement (κ = 1.00) for detection of endoleaks were excellent. The mean time delay between peak enhancement of the aorta and the endoleaks was significantly less for type I/III endoleaks (2.0 s ± 0) compared with type II endoleaks (5.3 s ± 1.0; P < .001).ConclusionsLow-dose dynamic volumetric CT angiography performed with the patient in Fowler position is feasible after EVAR. Dynamic information, including cine imaging, the timing of peak enhancement, and the Hounsfield units index, is useful in detecting and classifying endoleaks.     

Non-invasive fractional flow reserve in vessels without severe obstructive stenosis is associated with coronary plaque burden

AimsNon-invasive fractional flow reserve derived from coronary CT angiography (FFR_CT) has been shown to be predictive of lesion-specific ischemia as assessed by invasive fractional flow reserve (FFR). However, in practice, clinicians are often faced with an abnormal distal FFR_CT in the absence of a discrete obstructive lesion. Using quantitative plaque analysis, we sought to determine the relationship between an abnormal whole vessel FFR_CT (V-FFR_CT) and quantitative measures of whole vessel atherosclerosis in coronary arteries without obstructive stenosis.MethodsFFR_CT was calculated in 155 consecutive patients undergoing coronary CTA with ≥25% but less than 70% stenosis in at least one major epicardial vessel. Semi-automated software was used to quantify plaque volumes (total plaque [TP], calcified plaque [CP], non-calcified plaque [NCP], low-density non-calcified plaque [LD-NCP]), remodeling index [RI], maximal contrast density difference [CDD] and percent diameter stenosis [%DS]. Abnormal V-FFR_CT was defined as a minimum value of ≤0.75 across the vessel (at the most distal region where FFR_CT was computed).ResultsVessels with abnormal V-FFR_CT had higher per-vessel TP (554 vs 331 mm³), CP (59 vs 25 mm³), NCP (429 vs 295 mm³), LD-NCP (65 vs 35 mm³) volume and maximum CDD (21 vs 14%) than those with normal V-FFR_CT (median, p < 0.05 for all). Using a multivariate analysis to adjust for CDD and %DS, all measures of plaque volume were predictive of abnormal V-FFR_CT (OR 2.09, 1.36, 1.95, 1.95 for TP, CP, NCP and LD-NCP volume, respectively; p < 0.05 for all).ConclusionAbnormal V-FFR_CT in vessels without obstructive stenosis is associated with multiple markers of diffuse non-obstructive atherosclerosis, independent of stenosis severity. Whole vessel FFR_CT may represent a novel measure of diffuse coronary plaque burden.     

Incidental pulmonary nodules in emergent coronary CT angiography for suspected acute coronary syndrome: Impact of revised 2017 Fleischner Society Guidelines

BackgroundPulmonary nodules (PN) are frequently detected incidentally during coronary computed tomography angiography (CTA). We evaluated whether the 2017 Fleischner Society guidelines may result in a decrease of follow-up testing of incidental PN as compared to prior guidelines in patients undergoing coronary CTA.MethodsWe conducted a retrospective study of a registry of emergency department patients who underwent coronary CTA for acute coronary syndrome assessment between 2012 and 2017. Based on guidelines, patients <35 years, history of cancer, or prior exams showing stability of PN were excluded. Patients >60 years, history of smoking, irregular/spiculated PN morphology, or PN size >20 mm were classified as high-risk for lung cancer. Radiological findings pertaining to PN were identified (PN size, morphology, quantity) through review of radiology reports. PN follow-up recommendations were established using 2017 Fleischner Society Guidelines and compared with prior guidelines for solid (2005) and subsolid (2013) PN. Data were analyzed with Student's t-test.ResultsThe registry included 2066 patients (female 45.1%, 52.9 ± 11.0 years), of which 578 (28.0%) reported PN. 438 of those (21.2%) were eligible for guideline-based follow-up evaluation. 205 (4 6.8%) were classified as high-risk for lung cancer. 2017 guidelines reduced the number of individuals requiring follow-up by 64.5%, from 264 (12.8%) to 94 patients (4.5%) when compared to prior guidelines (p < 0.001). The minimum number of follow-up chest CTs decreased by 55.8% from 430 to 190 (p < 0.001).ConclusionApplication of the 2017 Fleischner Society Guidelines resulted in a significant decrease of follow-up testing for incidental PN in patients undergoing coronary CTA for suspected acute coronary syndrome.     

Hypertrophic Cardiomyopathy (HCM): New insights into Coronary artery remodelling and ischemia from FFRCT

IntroductionAngina, myocardial ischemia, and coronary artery physiology in hypertrophic cardiomyopathy (HCM) are poorly understood. However, coronary computed tomography angiography (CCTA) with fractional flow reserve from CT (FFRCT) analysis offers a non-invasive method for evaluation of coronary artery volume to myocardial mass ratio (V/M) that may provide insight into such mechanisms. Thus, we sought to investigate changes in V/M in HCM.MethodsA retrospective analysis was performed on 37 HCM patients and 37 controls matched for age, sex, and cardiovascular risk factors; CCTA-derived coronary artery lumen volume (V) and myocardial mass (M) were used to determine V/M. FFR_CT values were calculated for the left anterior descending (LAD), left circumflex (LCx) and right coronary (RCA) arteries as well as the 3-vessel cumulative FFR_CT values.ResultsHCM patients had significantly increased myocardial mass (176 ± 84 vs. 119 ± 27 g, p < 0.0001) and total coronary artery luminal volume (4112 ± 1139 vs. 3290 ± 924 mm³, p < 0.0001) that resulted from increases in segmented luminal volumes of both the left and right coronary artery systems. However, HCM patients had significantly decreased V/M (23.8 ± 5.9 vs. 26.5 ± 5.3 mm³/g; p = 0.026) which was further decreased when restricting V/M analysis to those HCM patients with septal hypertrophy (22.4 mm³/g, p = 0.01) that was mild-moderately predictive of HCM (AUC = 0.68). HCM patients also showed significantly lower nadir FFR_CT values in the LCx (0.87 ± 0.06 vs. 0.91 ± 0.06, p = 0.02), and cumulative 3-vessel FFR_CT values (2.58 ± 0.18 vs. 2.63 ± 0.14, p = 0.006).ConclusionsHCM patients demonstrate significantly greater coronary volume. Despite this, HCM patients suffer from decreased V/M. Further prospective studies evaluating the relationship between V/M, angina, and heart failure in HCM are needed.     

Imaging Follow-up of Endovascular Repair of Type B Aortic Dissection with Dual-Source,Dual-Energy CT and Late Delayed-Phase Scans

PurposeTo evaluate the diagnostic performance of dual-energy (DE) computed tomography (CT) after thoracic endovascular aortic repair (TEVAR) of type B dissection, and to investigate the value of late delayed (LD) acquisition in endoleak detection and false lumen patency assessment.Materials and MethodsTwenty-four patients with TEVAR for type B dissection underwent 53 tripe-phase CT examinations. Single-source unenhanced acquisition was followed by single-source arterial-phase and DE LD phase (300-s delay) imaging. Virtual noncontrast images were generated from DE acquisition. Two blinded radiologists retrospectively evaluated the cases in three reading sessions: session A (triphasic protocol), session B (virtual noncontrast and arterial phase), and session C (virtual noncontrast and arterial and LD phases). Endoleak detection accuracy during sessions B and C compared with session A (reference standard) was investigated. False lumen patency was assessed. Effective radiation dose was calculated.ResultsSession A revealed 37 endoleaks in 30 of 53 studies (56.6%). Session B revealed 31 of the 37 endoleaks, with one false-positive case, 83.8% sensitivity, 95.8% specificity, 79.3% negative predictive value, and 96.9% positive predictive value. Session C correctly depicted all 37 endoleaks, with one false-positive case, 100% sensitivity, 95.8% specificity, 100% negative predictive value, and 97.4% positive predictive value. Underestimation of false lumen patency was found in session B (P = .013). Virtual noncontrast imaging resulted in 17% radiation exposure reduction.ConclusionsVirtual noncontrast imaging can replace standard unenhanced images in follow-up after TEVAR of type B dissection, thus reducing radiation dose. Delayed-phase imaging is valuable in low-flow endoleaks detection and false lumen patency assessment.     

Incidentally detected atherosclerosis in the abdominal aorta or its major branches on computed tomography is highly associated with coronary heart disease in asymptomatic adults

BackgroundAtherosclerotic lesions in the abdominal aorta or its major branches are often incidentally detected on abdominal CT. However, clinical implications and optimal subsequent management are mostly left undetermined.MethodsConsecutive, asymptomatic adults (age≥30) who underwent both abdominal CT and coronary computed tomography angiography as part of a self-referred health check-up were investigated (n = 1494).ResultsAdjusted for cardiovascular risk factors, abdominal atherosclerotic lesions with stenosis<25% were associated with significant coronary stenosis, especially in the abdominal aorta (adjusted odds ratio [aOR] 3.37, 95% confidence interval [CI] 0.99–11.45) and any common iliac artery (aOR 2.99, 95% CI 1.43–6.26). The association was higher in atherosclerotic lesions with stenosis≥25%, respectively (aOR 16.39, 95% CI 4.00–67.11; aOR 7.32, 95% CI 2.84–18.86). Furthermore, any major abdominal artery stenosis added predictive value to significant coronary stenosis (area under the receiver operating curve: 0.7598 vs. 0.8019, P < 0.001). The extent of arterial territory involvement was associated with the presence of significant coronary stenoses (P for trend <0.001).ConclusionStenotic atherosclerotic lesions in the abdominal aorta or its major branches incidentally detected on abdominal CT are relatively prevalent and carry high risk for asymptomatic coronary arterial disease.     

Incidence and predictors of lesion-specific ischemia by FFRCT: Learnings from the international ADVANCE registry

BackgroundTo date, the clinical utility of coronary computed tomography angiography (CTA)-derived fractional flow reserve (FFRCT) has been limited to trials and single center experiences. We herein report the incidence of abnormal FFRCT (≤0.80) and the relationship of lesion-specific ischemia to subject demographics, symptoms, and degree of stenosis in the multicenter, prospective ADVANCE registry.MethodsOne thousand patients with suspected angina having documented coronary artery disease on coronary CTA and clinically referred for FFRCT were prospectively enrolled in the registry. Patient demographics, symptom status, coronary CTA and FFRCT findings were recorded. Univariate and multivariate analyses were performed to investigate the predictors related to abnormal FFR_CT.ResultsFFR_CT data were analyzed in 952 patients (95.2%). Overall, 51.1% patients had a positive FFR_CT value (≤0.80). Patients with ≥3 risk factors had a significantly higher rate of abnormal FFR_CT than those with <3 risk factors (60.2% vs. 43.9%, p = 0.0001). On multivariate analysis, baseline diabetes (odds ratio [OR] 1.52, 95% confidence interval [CI] 1.04–2.21, p = 0.030) and hypertension (OR 1.56, 95%CI 1.14–2.14, p = 0.005) were both predictive of abnormal FFR_CT. In addition, >70% stenosis was significantly associated with low FFR_CT (OR 31.16, 95%CI 12.25–79.22, p < 0.0001) vs. <30% stenosis. Notably, stenosis 30–49% vs. <30% had an increased likelihood of ischemia (OR 3.74, 95%CI 1.52–9.17, p < 0.0001).ConclusionsIn this real-world registry, CT angiographic stenosis severity in addition to baseline cardiovascular risk factors conferred an increased likelihood of an abnormal FFR_CT. Importantly, however, mild CT angiographic stenoses were noted to have an increased hazard for ischemia and the converse holding true for more severe stenoses as well.     

Renal Artery Fibromuscular Dysplasia in 2,640 Renal Donor Subjects: A CT Angiography Analysis

PurposeTo present the incidence, demographics, and clinical presentation of patients diagnosed with renal fibromuscular dysplasia (FMD) who underwent computed tomography (CT) angiography for evaluation of living renal donor protocol.Methods and MaterialsA retrospective review was performed from January 1, 2000, to December 31, 2011 on patients who underwent CT angiography for evaluation of living renal donor protocol. Of 2,640 patients identified, only patients with a diagnosis of FMD by the radiology report underwent independent reader evaluation of CT angiography for the presence of FMD and associated characteristics. The demographics, medical history, and presentation were reviewed using the electronic medical chart.ResultsThe independent readers who evaluated CT angiography identified a diagnosis of FMD in 68 patients (2.6%; 59 female) with an average age of 52 years ± 10. Unilateral FMD was observed in 46 patients (68%), and bilateral FMD was observed in 22 patients (32%). Three patients had aneurysms of the renal artery. Comorbidities included hypertension (n = 21, 31%), dyslipidemia, (n = 13, 19%), history of migraines (n = 3, 4%), and history of smoking (n = 14, 21%). No patients had diabetes mellitus, coronary artery disease, or family history of FMD. Of 21 patients (31%) with a history of hypertension, 13 patients (62%) were treated with antihypertensive medications.ConclusionsThe incidence of FMD in patients who underwent CT angiography for evaluation of living renal donor protocol is 2.6%.     

Prevalence and impact of scan-related anxiety during coronary CT angiography: A prospective cohort study of 366 patients

BackgroundScanxiety, the anxiety/stress associated with an imaging test, has never been evaluated in relation to coronary CT angiography (Coronary CTA). As it could impact heart rate and thereby affect image quality of Coronary CTA, we aimed to evaluate the prevalence, severity, and impact of scanxiety on quality and interpretability of Coronary CTA.Methods366 consecutive patients were prospectively presented with a clinical questionnaire comprising two tests to evaluate their scan-related anxiety: the Impact of Event IES-6 (6 questions, final score 0–24) and a visual stress-scale (1 question, score 1–10). Patient demographics, heart rate and final image quality scored by two readers were recorded. Potential independent correlations were sought between IES-6 scanxiety level and image quality, heart rate variability and demographics, using an ordinal logistic regression model.Results344 patients (59.9% men, 57.6 ± 10.7yo) completed the questionnaire. 74.1% (255 patients) reported some scan-related distress, with a mean IES-6 score of 4.1 ± 4.3 (range 0–18). There was no significant difference in terms of age, sex or indications for Coronary CTA between the non-anxious (IES-6 = 0) and the anxious (IES-6>0) patients. There was no significant independent correlation between image quality and IES-6 score (OR = 0.98, p = 0.62), nor between IES-6 score and heart rate variability (effect = −0.005, p = 0.97).ConclusionThe prevalence of scan-related anxiety – aka scanxiety – in Coronary CTA patients is high (74.1%) but does not appear to impact image quality and interpretability.     

Relationship of Thrombus Length to Number of Stent Retrievals,Revascularization, and Outcomes in Acute Ischemic Stroke

PurposeTo study the relationship between intracranial thrombus length and number of stent retrievals, revascularization rates, and functional outcomes in stroke.Materials and MethodsRetrospective data were collected from consecutive cases of stroke treated with endovascular procedures at a single institution from April 2012–September 2013. Thrombus length was measured in the anterior cerebral circulation. Demographic and clinical details; involved vessels; and procedural details, including the number of devices used and number of retrievals used for each device, were recorded. Revascularization rates and 90-day functional outcomes were recorded.ResultsData regarding the length of thrombus in the anterior cerebral circulation were available for 28 patients. There was no significant association between thrombus length and number of stent retrievals (P = .3780), final thrombolysis in cerebral infarction (TICI) score (P = .4835), or 90-day modified Rankin Scale score (P = .4146). There was a significant difference (P = .0280) between number of retrievals and final TICI score, with lower number of retrieval passes corresponding to higher final TICI scores.ConclusionsThe data suggest no relationship between thrombus length and number of stent retrievals, final TICI score, or functional neurologic outcomes at 90 days in stent retrieval thrombectomy for acute ischemic stroke. These results do not support a predictive value for thrombus length quantification in the evaluation of stroke.     

High-pitch versus sequential mode for coronary calcium in individuals with a high heart rate: Potential for dose reduction

BackgroundTo determine the impact of high-pitch spiral acquisition on radiation dose and cardiovascular disease (CVD) risk stratification by coronary artery calcium (CAC) assessment with computed tomography in individuals with a high heart rate.MethodsOf the ROBINSCA trial, 1990 participants with regular rhythm and heart rates >65 beats per minute (bpm) were included. As reference, 390 participants with regular heart rates ≤65 bpm were used. All participants underwent prospectively electrocardiographically(ECG)-triggered imaging of the coronary arteries using dual source CT at 120 kVp, 80 ref mAs using both high-pitch spiral mode and sequential mode. Radiation dose, Agatston score, number of positive scores, as well as median absolute difference of the Agatston score were determined and participants were stratified into CVD risk categories.ResultsA similar percentage of participants with low heart rates and high heart rates had a positive CAC score in data sets acquired in high-pitch spiral (low heart rate: 57.7%, high heart rate: 55.8%) and sequential mode (58.0%, 54.7%, p = n.s.). The median absolute difference in Agatston scores between acquisition modes was 14.2% and 9.2%, for the high and low heart rate groups, respectively. Excellent agreement for risk categorization between the two data acquisition modes was found for the high (κ = 0.927) and low (κ = 0.946) heart rate groups. Radiation dose was 48% lower for high-pitch spiral versus sequential acquisitions.ConclusionRadiation dose for the quantification of coronary calcium can be reduced by 48% when using the high-pitch spiral acquisition mode compared to the sequential mode in participants with a regular high heart rate. CVD risk stratification agreement between the two modes of data acquisition is excellent.     

Utility of Cone-Beam CT Imaging in Prostatic Artery Embolization

PurposeTo evaluate the utility of cone-beam computed tomography (CT) in patients undergoing prostatic artery (PA) embolization (PAE) for benign prostatic hyperplasia.Materials and MethodsFrom January 2012 to January 2013, 15 patients (age range, 59–81 y; mean, 68 y) with moderate- or severe-grade lower urinary tract symptoms, in whom medical management had failed were enrolled in a prospective United States trial to evaluate PAE. During pelvic angiography, 15 cone-beam CT acquisitions were performed in 11 patients, and digital subtraction angiography was performed in all patients. Cone-beam CT images were reviewed to assess for sites of potential nontarget embolization that impacted therapy, a pattern of enhancement on cone-beam CT suggesting additional PAs, confirmation of prostatic parenchymal perfusion before embolization, and contralateral prostatic parenchymal enhancement.ResultsCone-beam CT was successful in 14 of 15 acquisitions, and PAE was successful in 14 of 15 patients (92%). Cone-beam CT provided information that impacted treatment in five of 11 patients (46%) by allowing for identification of sites of potential nontarget embolization. Duplicated prostatic arterial supply and contralateral perfusion were each identified in 21% of patients (three of 11). Prostatic perfusion was confirmed before embolization in 50% of acquisitions (seven of 14).ConclusionsCone-beam CT is a useful technique that can potentially mitigate the risk of nontarget embolization. During treatment, it can allow for the interventionalist to identify duplicated prostatic arterial supply or contralateral perfusion, which may be useful when evaluating a treatment failure.