Efficacy and safety of coronary computed tomography angiography in diagnosing coronary lesions in children

INTRODUCTION

Identification of paediatric coronary artery abnormalities is challenging. We studied whether coronary artery CT angiography can be performed safely and reliably in children.

MATERIALS

Retrospective analysis of consecutive coronary CT angiography scans was performed for image quality and estimated radiation dose. Both factors were assessed for correlation with electrocardiographic-gating technique that was protocoled on a case-by-case basis, radiation exposure parameters, image noise artefact parameters, heart rate, and heart rate variability.

RESULTS

Sixty scans were evaluated, of which 96.5% were diagnostic for main left and right coronaries and 91.3% were considered diagnostic for complete coronary arteries. Subjective image quality correlated significantly with lower heart rate, increasing patient age, and higher signal-to-noise ratio. Estimated radiation dose only correlated significantly with choice of electrocardiographic-gating technique with median doses as follows: 2.42 mSv for electrocardiographic-gating triggered high-pitch spiral technique, 5.37 mSv for prospectively triggered axial sequential technique, 3.92 mSv for retrospectively gated technique, and 5.64 mSv for studies which required multiple runs. Two scans were excluded for injection failure and one for protocol outside the study scope. Five non-diagnostic cases were attributed to breathing motion, scanning prior to peak contrast enhancement, or scan acquisition during the incorrect portion of the R-R interval.

CONCLUSIONS

Diagnostic-quality coronary CT angiography can be performed reliably with a low estimated radiation exposure by tailoring each scan protocol to the patient's body habitus and heart rate. We propose coronary CT angiography is a safe and effective diagnostic modality for coronary artery abnormalities in children.

Shortest Apposition Length at the First Postoperative Computed Tomography Angiography Identifies Patients at Risk for Developing a Late Type Ia Endoleak After Endovascular Aneurysm Repair

PURPOSE

Imaging surveillance following endovascular aneurysm repair (EVAR) is strictly recommended. This study investigates the value of endograft apposition and position relative to the aortic neck on the first postoperative computed tomography angiography (CTA) in determining patients at risk for a late type Ia endoleak (T1aEL).

MATERIALS AND METHODS

Patients with a T1aEL after the first postoperative CTA were selected from a consecutive database and matched with uncomplicated controls. Endograft apposition and position, including the shortest apposition length (SAL), were determined on the first postoperative CTA. The SAL is the shortest distance between the proximal endograft fabric and the first slice where circumferential apposition with the aortic wall is lost. Differences in endograft apposition at the first postoperative CTA were compared between groups. Logistic regression analysis identified independent predictors for late T1aEL.

RESULTS

A total of 32 patients with a late T1aEL were included and matched with 32 uncomplicated controls. Median follow-up after primary EVAR was 62.0 (interquartile range [IQR]: 36.8, 83.5) months in the T1aEL group compared with 47.5 (IQR: 34.0, 79.3) months in the control group; p=0.265. Median preoperative neck diameter was significantly larger in the T1aEL group than in the control group (26.6 [IQR: 24.9, 29.6] mm versus 23.4 [IQR: 22.5, 25.3] mm); p<0.001. Patients in the T1aEL group had a median SAL of 11.6 (IQR: 4.3, 20.5) mm compared with 20.7 (IQR: 13.1, 24.9) mm in the control group; p=0.002. SAL <10mm on the first postoperative CTA (odds ratio [OR]: 9.63, 95% confidence interval [CI]: 1.60-57.99) and larger neck diameter (OR: 1.80, 95% CI: 1.26-2.57) were independent predictors for developing a late T1aEL.

CONCLUSION

Preoperative neck diameter and SAL on the first postoperative CTA following EVAR are important predictors for the development of a late T1aEL. Patients with a SAL of <10mm had a significantly higher risk of developing a late T1aEL. Future research should determine whether these patients would benefit from reintervention before an actual T1aEL is present.

CLINICAL IMPACT

Understanding the mechanisms of endovascular aneurysm repair failure is essential to further enhance clinical outcomes. Adequate proximal sealing is necessary to foster freedom from type 1a endoleak. This study demonstrates that the shortest apposition length (SAL) at the first postoperative computed tomography angiography (CTA) is able to identify patients at risk for a late type 1a endoleak. Especially patients with a SAL <10mm are at high risk. Currently, the guidelines advice repeated imaging with CTA in patients with a seal <10mm. Future research should determine whether these patients would benefit from re-intervention before an actual type 1a endoleak is present.

Maternal and Fetal Radiation-Induced Cancer Risk From Computed Tomography Pulmonary Angiography During Pregnancy: A Retrospective Cohort Study Across a Multihospital Integrated Health Care Network

OBJECTIVE

Computed tomography pulmonary angiogram (CTPA) is important to evaluate suspected pulmonary embolism in pregnancy but has maternal/fetal radiation risks. The objective of this study was to estimate maternal and fetal radiation-induced cancer risk from CTPA during pregnancy.

METHODS

Simulation modeling via the National Cancer Institute's Radiation Risk Assessment Tool was used to estimate excess cancer risks from 17 organ doses from CTPA during pregnancy, with doses determined by a radiation dose indexing monitoring system. Organ doses were obtained from a radiation dose indexing monitoring system. Maternal and fetal cancer risks per 100,000 were calculated for male and female fetuses and several maternal ages.

RESULTS

The 534 CTPA examinations had top 3 maternal organ doses to the breast, lung, and stomach of 17.34, 15.53, and 9.43 mSv, respectively, with a mean uterine dose of 0.21 mSv. The total maternal excess risks of developing cancer per 100,000 were 181, 151, 121, 107, 94.5, 84, and 74.4, respectively, for a 20-, 25-, 30-, 35-, 40-, 45-, and 50-year-old woman undergoing CTPA, compared with baseline cancer risks of 41,408 for 20-year-old patients. The total fetal excess risks of developing cancer per 100,000 were 12.3 and 7.3 for female and male fetuses, respectively, when compared with baseline cancer risks of 41,227 and 48,291.

DISCUSSION

Excess risk of developing cancer from CTPA was small relative to baseline cancer risk for pregnant patients and fetuses, decreased for pregnant patients with increasing maternal age, and was greater for female fetuses than male fetuses.

Association of epicardial adipose tissue with metabolic risk factors on cardiovascular outcomes: serial coronary computed tomography angiography study

BACKGROUND/AIMS

Epicardial adipose tissue (EAT) shares pathophysiological properties with other visceral fats and potentially triggers local inflammation. However, the association of EAT with cardiovascular disease (CVD) is still debatable. The study aimed to observe the changes and associations in EAT and risk factors over time, as well as to investigate whether EAT was associated with CVD.

METHODS

A total of 762 participants from Seoul National University Hospital (SNUH) and SNUH Gangnam Center were included in this study. EAT was measured using coronary computed tomography angiography.

RESULTS

Baseline EAT level was positively associated with body mass index (BMI), calcium score, atherosclerotic cardiovascular disease (ASCVD) 10-year risk score, glucose, triglycerides (TG)/high-density lipoprotein (HDL), but not with total cholesterol, low-density lipoprotein (LDL). At follow-up, EAT levels increased in all groups, with low EAT groups demonstrating a significant increase in EAT per year. Change in EAT was associated with a change in BMI, TG/HDL, and glucose, while changes in LDL, calcium score, and ASCVD 10-year risk score were not associated. Although calcium score and ASCVD 10-year risk score were associated with CVD events, baseline information of EAT, baseline EAT/body surface area, or EAT change was not available.

CONCLUSION

Metabolic risks, e.g., BMI, TG/HDL, and glucose, were associated with EAT change per year, whereas classical CVD risks, e.g., LDL, calcium score, and ASCVD 10-year risk score, were not. The actual CVD event was not associated with EAT volume, warranting future studies combining qualitative assessments with quantitative ones.

Association between cervical fracture patterns and blunt cerebrovascular injury when screened with computed tomographic angiography

BACKGROUND CONTEXT

Prior studies have demonstrated a close association between cervical spine fractures and blunt cerebrovascular injuries (BCVI). Undiagnosed BCVI is a feared complication because of the potentially catastrophic outcomes in a missed posterior circulation stroke. Computed tomography angiography (CTA) is commonly used to screen BCVI in the trauma setting. However, determining which cervical fracture patterns mandate screening is still not clearly known.

PURPOSE

The aim of this retrospective review is to further elucidate which fracture patterns are associated with BCVI when using CTA and may mandate screening.

STUDY DESIGN/SETTING

Retrospective cohort study.

PATIENT SAMPLE

All patients that presented to our trauma and emergency departments with a blunt cervical spine fracture from January 2018 to December 2021. Inclusion criteria included blunt cervical trauma and the use of CTA for BCVI screening. Exclusion criteria included patients under the age of 18, penetrating cervical trauma, and use any imaging modality besides CTA for BCVI screening.

OUTCOME MEASURES

Patient demographics (age, gender, Glasgow coma scale, hospital length of stay (LOS), intensive care unit LOS, mechanism of energy of injury, polytrauma status), fracture location, fracture pattern (anterior arch, dens, dislocations/subluxations, facet, hangman, Jefferson, lamina, lateral mass, occipital condyle dissociation, occipital condyle, pedicle, posterior arch, spinous process, transverse process, transverse foramen, and vertebral body), and whether the patient sustained a BCVI or CVA.

METHODS

If a patient had multiple fracture levels or fracture patterns, each level and pattern was counted as a separate BCVI. Multilevel fractures were defined as any patient with fractures at two distinct cervical levels. Differences between the patients who had a BCVI and those who did not were analyzed using independent sample t-tests for continuous variables and the chi-square or Fisher exact test for categorical variables. Odds ratios and 95% confidence intervals were calculated to assess likelihood between patient characteristics/fracture characteristics and BCVI.

RESULTS

A total of 690 patients were identified as having a blunt cervical spine injury. A total of 453 patients (66%) underwent screening for BCVI with CTA. Among patients who underwent CTA, BCVI was diagnosed in 138 patients (30%), VAI in 119 patients (26%), CAI in 30 patients (7%), and 11 patients were diagnosed with both a VAI and CAI (2%). Overall, among all patients there were 9 strokes, all in patients identified with a BCVI (1%). No individual cervical level was associated with increased risk of BCVI, but when combined, OC-C3 fractures were associated with an increased risk (OR: 1.4, 95% CI: 1.0-1.9, p-value: .006). Multilevel fractures were also associated with an increased risk (OR: 1.7, 95% CI: 1.1-2.3, p-value: .01). The only fracture pattern associated with increased risk of BCVI were fractures associated with a dislocation/subluxation (OR: 3.8, 95% CI: 1.9-7.8, p-value = .0001).

CONCLUSIONS

The only fracture pattern associated with an increased risk of BCVI were fractures associated with dislocation/subluxation. The only fracture levels associated with BCVI were combined OC-C3 and multilevel fractures. We recommend that any upper cervical fracture (OC-C3), multilevel fracture, or fracture with dislocation/subluxation undergo screening for BCVI.

Diagnostic utility of CT angiography compared with endoscopy in patients with acute GI hemorrhage

BACKGROUND AND AIMS

Because it is minimally invasive, CT angiography (CTA) has emerged as an attractive diagnostic tool for investigation of acute GI hemorrhage.

METHODS

This study examined patients with acute GI bleeding who underwent CTA.

RESULTS

CTA was the initial diagnostic examination in 177 patients, identifying upper and lower GI bleeding lesions in 16 and 27 patients, respectively. In 103 patients with an initial negative CTA, 78 had endoscopy (32 EGD and 46 colonoscopy/flexible sigmoidoscopy), of whom 52 (67%) had a bleeding lesion identified, including 23 with a high-risk bleeding lesion requiring therapy. Peptic ulcer disease and diverticular bleeding were the most commonly identified bleeding lesions. With endoscopy as a criterion standard, the sensitivity of CTA for the detection of a source of GI bleeding was 20%.

CONCLUSIONS

CTA has very poor sensitivity for identification of a GI bleeding source or lesion, suggesting that CTA should not be used as an initial diagnostic test.

Prevalence of high-risk aortic arch atherosclerosis features on computed tomography angiography in embolic stroke of undetermined source

INTRODUCTION

Embolic stroke of undetermined source (ESUS) comprises a heterogenous group. There is a need to further identify etiologies within this group to guide management strategies. We examined the prevalence of aortic arch atherosclerosis (AAA) on CT angiography (CTA) in patients with embolic stroke of undetermined source (ESUS) to characterize high-risk plaque features.

METHODS

All patients from two prospective multicenter acute ischemic stroke studies (INTERRSeCT and PRove-IT) were included if the CTA adequately imaged the proximal aortic arch and the stroke etiology was recorded. Three readers blinded to stroke etiology analyzed the following AAA plaque features on baseline CTA at the time of stroke: 1) thickness in millimetres (mm); 2) morphology (none, smooth, ulcerated, or protruding); 3) location within the aortic arch (proximal, transverse, or distal); and 4) calcification (none, single small, multiple small, single large, or diffuse extensive).

RESULTS

We included 1063 patients, of which 293 (27.6%) had ESUS (mean age 67.5 years; 46.4% men; median NIHSS 12; 80.6% large vessel occlusion). Mean AAA thickness was significantly larger in ESUS patients (3.8 mm) compared to non-ESUS patients (3.0 mm; p<0.0001) and to a subgroup of patients with large artery atherosclerosis (2.9 mm; p=0.003). ESUS patients had a significantly higher proportion of ulcerated or protruding plaques (17.4% vs 10.3%; risk ratio 1.7, 95% C.I. 1.2-2.4, p=0.002). The location of AAA in the ESUS group was the ascending aorta in 37.9%, transverse arch in 42.3%, and descending aorta in 84.6%. Although AAA was mostly located in the distal aortic arch, ulcerated or protruding plaques were least common in the distal arch (p=0.002). There was no difference between ESUS and non-ESUS patients in plaque location (p=0.23) or calcification grade (p=0.092).

CONCLUSION

ESUS patients in our study had thicker AAA and a higher prevalence of ulcerated or protruding plaques located more proximally within the aortic arch. High-risk plaque features may suggest a causal role of AAA in the ESUS population with visible intracranial occlusions.

Chimney Technique and Single-Branched Stent Graft for the Left Subclavian Artery Preservation During Zone 2 Thoracic Endovascular Aortic Repair for Type B Acute Aortic Syndromes

PURPOSE

The purpose of this study was to evaluate the efficacy and safety of zone 2 thoracic endovascular aortic repair assisted by the chimney technique or single-branched stent graft for the preservation of the left subclavian artery, and summarize our single-center experience with the techniques.

MATERIALS AND METHODS

From February 2017 to June 2020, 137 patients who underwent left subclavian artery revascularization during zone 2 thoracic endovascular aortic repair were enrolled. Patients had acute type B aortic dissection and penetrating aortic ulcer associated with intramural hematoma. The chimney technique was performed in 68 patients (group A), and single-branched stent graft was deployed in 69 patients (group B). All procedures were performed during the acute phase. Primary technical success, immediate postoperative endoleak, neurologic complications (stroke or spinal cord ischemia), 30-day mortality, 1-year technical success, all-cause mortality, patency of the left subclavian artery, and reintervention were analyzed. Comparing the occurrence of the Bird-Beak Configuration, defined as a gap between the aortic wall and the sent graft with stent protrusion into the aortic lumen more than 5 mm, was also performed.

RESULTS

Primary technique success was achieved in 66 and 67 patients in groups A and B, respectively. The incidence of immediate postoperative endoleak, neurologic complications (stroke or spinal cord ischemia), and 30-day mortality were 5.9%, 1.5%, and 4.4% in group A, and 2.9%, 2.9%, and 2.9% in group B, respectively. During follow-up, the 1-year technical success rate was similar in both groups. All-cause mortality was similar in both groups (3.1% in group A and 4.5% in group B). The patency of the left subclavian artery was not significantly different between the 2 groups with 2 and 3 occlusions in groups A and B, respectively. The rate of reintervention was higher in group B (3.1% vs 1.6%, p=0.536), with a non-significant difference. Bird-Beak Configuration was more prominent in group B with the incidence of 59.42%.

CONCLUSIONS

Acting as minimally invasive alternatives, both techniques are feasible for left subclavian artery preservation during zone 2 thoracic endovascular aortic repair for type B acute aortic syndromes with encouraging mid-term outcomes. Long-term follow-up is required to confirm these findings.

The role of post-dilatation in carotid MicroNet-covered stent implantation, evaluated using 3D cone-beam CT angiography

BACKGROUND

This study aims to assess the role and safety of post-dilatation in protected carotid artery stenting (PCAS) using the new MicroNet-covered 2nd-generation stent assessed by cone beam CT scans.

METHODS

From March 2020 to March 2022, patients were enrolled in the study according to CT angiography results based on the following criteria: Evidence of 70% to 99% carotid stenosis in asymptomatic patients and 50% to 99% in symptomatic patients, per the NASCET index. Using a FilterWire EZ™ (Boston Scientific, Natick, MA, USA) embolic protection system (EPS), MicroNet-covered stent PCAS was performed by two interventional radiologists with at least 8 years of experience in endovascular intervention. Each patient underwent post-dilatation following stent placement. Finally, a third radiologist (not participating in the interventional procedures) evaluated the cone beam CT scans and calculated residual stenosis. Major and minor complications were recorded in the 30 days following the procedure.

RESULTS

A total of 192 patients (121 male, mean age 73±10 years) were included in the study, and all patients received post-dilatation following stent implantation. Technical successes were achieved in all procedures. Adverse events noted in this study were limited to periprocedural transient ischemic attacks that occurred in three out of 192 patients (1.6%) and showed a swift complete recovery. The post-dilatation balloon diameters used in the study were: 5.0 mm (30.3%), 5.5 mm (39.3%) and 6 mm (30.3%). Optimized postdilatation resulted in a significant increase in the final luminal area. Similar improvements were observed in all subtypes of plaque.

CONCLUSIONS

Post-dilatation in protected CAS is safe and induces a significant improvement in the cross-sectional area regardless of the stenotic plaque.

Nonthrombotic Pulmonary Embolism Associated With Non-Hodgkin Lymphoma

Nonthrombotic pulmonary embolism (NTPE) challenges the medical community with its diverse etiologies and potential life-threatening implications. The classification section delves into the multifaceted nature of NTPE, which includes various embolic agents that traverse the vascular system. From air and fat emboli to tumor and amniotic fluid emboli, this exploration of diverse etiologies sheds light on the complexity of NTPE. Diagnostic methods play a crucial role in the effective management of NTPE. This article describes a range of traditional and cutting-edge diagnostic techniques, from computed tomography angiography to novel biomarkers, enabling the accurate and timely identification of NTPE. NTPE treatment options are diverse and patient-specific, requiring customized approaches to address varying embolic sources. Anticoagulation, embolus removal, and emerging interventions under study are discussed, providing clinicians with a comprehensive understanding of management strategies. This article uncovers the rare but captivating association between NTPE and non-Hodgkin lymphoma. Although rare, documented cases have sparked curiosity among researchers and medical practitioners. We explore potential pathophysiological connections, discussing challenges and considerations when encountering this unique scenario. In conclusion, this captivating review encapsulates the multifaceted realm of NTPE, covering its classification, diagnostics, and treatment modalities. Moreover, it presents a fascinating connection with non-Hodgkin lymphoma. This article offers a comprehensive and concise review of NTPE, guiding readers through its intricate classification, diagnostic approaches, and therapeutic interventions.

Prognostic utility of semi-quantitative coronary computed tomography angiography scores in the SCOT-HEART trial

BACKGROUND

Information from cardiac computed tomography angiography can be summarized using visual semi-quantitative scores. However, the optimal method and their prognostic utility is unknown.

METHODS

Five semi-quantitative scores were calculated in the SCOT-HEART trial, including segment involvement score (SIS), segment stenosis score (SSS), CT Leaman (CT-LeSc), multivessel aggregate stenosis score (MVAS), and CAD-RADS 2.0 including plaque modifier (P). Prediction of fatal or non-fatal myocardial infarction and major adverse cardiovascular events (MACE) was compared to the 10-year cardiovascular risk score.

RESULTS

Imaging was performed in 1,769 individuals (age 58 ​± ​10 years, 56% male) with 41 (2.3%) experiencing myocardial infarction and 74 (4%) MACE over 4.9 ​± ​1.1 years. P based on calcium score and SIS had good agreement (weighted Cohen's kappa 0.79, 95% confidence interval [CI] 0.79, 0.79). SIS, SSS, CT-LeSec, and MVAS performed similarly for the prediction of myocardial infarction (area under the curve [AUC] 0.74, 0.75, 0.75, 0.74, all p ​> ​0.1) and MACE (AUC 0.73, 0.74, 0.74, 0.73, all p ​> ​0.1), and were superior to the cardiovascular risk score (AUC 0.62 and 0.65, both p ​< ​0.001). High semi-quantitative scores were associated with increased risk of myocardial infarction and MACE, with the greatest adjusted risk associated with CT-LeSc≥8 (Hazard ratio [HR] 5.6, 95% confidence interval [CI] 2.7, 11.6, p ​< ​0.001 and HR 5.2, 95% CI 3.1, 8.7, p ​< ​0.001) and SSS≥10 (HR 4.7, 95% CI 2.4, 8.9, p ​< ​0.001 and HR 5.3, 95% CI 3.3, 8.5, p ​< ​0.001).

CONCLUSIONS

Semi-quantitative scores performed similarly for the prediction of myocardial infarction and MACE, with all superior to the cardiovascular risk score.

Carotid calcium burden derived from computed tomography angiography as a predictor of all-cause mortality after carotid endarterectomy

OBJECTIVE

Carotid endarterectomy (CEA) aims to reduce the risk of stroke in patients with atherosclerotic carotid disease. Preoperative risk assessments that predict complications are needed to optimize the care in this patient group. The current approach, namely relying solely on symptomatology and degree of stenosis, is outdated and calls for innovation. The Agatston calcium score was applied in several vascular specialties to assess cardiovascular risk profile but has been little studied in carotid surgery. It is hypothesized that a higher calcium burden at initial presentation equates to a worse prognosis attributable to an increased cerebrovascular and cardiovascular risk profile. The aim was to investigate the association between preoperative ipsilateral calcium score and postoperative all-cause mortality in patients undergoing CEA.

METHODS

This single-center retrospective cohort study included 89 patients who underwent CEA at a tertiary referral center between 2010 and 2018. Preoperative calcium scores were measured on contrast-enhanced computed tomography images with patient-specific Hounsfield thresholds at the level of the carotid bifurcation. The association between these calcium scores and all-cause mortality was analyzed using multivariable adjusted Cox proportional hazard analysis.

RESULTS

Cox proportional hazard analysis demonstrated a significant association between preoperative ipsilateral carotid calcium score and all-cause mortality (hazard ratio, 1.10; 95% confidence interval, 1.03-1.16; P = .003). After adjusting for age, preoperative estimated glomerular filtration rate, and diabetes mellitus, a significant association remained (hazard ratio, 1.07; 95% confidence interval, 1.00-1.15; P = .05).

CONCLUSIONS

A higher calcium burden was predictive of worse outcome, which might be explained by an overall poorer health status. These results highlight the potential of calcium measurements in combination with other traditional risk factors, for preoperative risk assessment and thus for improved patient education and care.

Detection of Endoleaks Following Thoracic and Abdominal Aortic Endovascular Aortic Repair-: A Comparison of Standard and Dynamic 4D-Computed Tomography Angiography

PURPOSE

Endoleaks are a common complication after endovascular aortic repair (EVAR) and thoracic endovascular aortic repair (TEVAR). The detection and correct classification of endoleaks is essential for the further treatment of affected patients. However, standard computed tomography angiography (CTA) provides no hemodynamic information on endoleaks, which can result in misclassification in complex cases. The aim of this study was to compare standard CTA (sCTA) with dynamic, dual-energy CTA (dCTA) for detection and classification of endoleaks following EVAR or TEVAR.

MATERIALS AND METHODS

This retrospective evaluation compared 69 sCTA diagnostic examinations performed on 50 different patients with 89 dCTA diagnostic examinations performed on 69 different patients.

RESULTS

In total, 15.9% of sCTA examinations and 49.4% of dCTA examinations led to the detection of endoleaks. With sCTA, 20.0% of patients were diagnosed with endoleaks, while with dCTA, 37.7% of patients were diagnosed with endoleaks. With sCTA, mainly Type 1 endoleaks were detected, whereas, with dCTA, the types of detected endoleaks were more evenly distributed. In comparison with the literature, the frequencies of endoleak types detected with dCTA better reflect the natural distribution than the frequencies detected with standard CTA.

CONCLUSION

Based on the retrospective comparative evaluation, dCTA could pose a valuable supplementary diagnostic tool resulting in a more accurate and realistic detection and classification of suspected endoleaks.

Management of a recurrent stroke due to a carotid web

Carotid web is a rare intraluminal parietal protrusion in the carotid artery. This vascular anomaly mostly occurs at the bifurcation causing turbulent flow, and is responsible of thrombi formation associated with embolic ischemic events. We report the case of a 35-year-old woman, with no medical history, who presented a recurrent middle cerebral artery (MCA) occlusion within twelve hours caused by a carotid bulb web. Although considered as a rare entity, carotid web is associated with the risk of recurrent strokes in the MCA territory and especially in the absence of the typically recognized risk factors. The key imaging is the CT angiography that shows the web, the cerebral artery occlusion, and the outcome appreciation. Therapeutic strategy associates antithrombotic treatment and operative management with stenting of the carotid web or endarterectomy.

Pseudoaneurysm after High-Grade Penetrating Solid Organ Injury and Utility of Delayed CT Angiography

BACKGROUND

Leaving an injured solid organ in situ allows preservation of structure function but invites complications from the damaged parenchyma, including pseudoaneurysms (PSAs). Empiric PSA screening after solid organ injury is not yet established, particularly following penetrating trauma. The study objective was definition of delayed CT angiography (dCTA) yield in triggering intervention for PSA after penetrating solid organ injury.

METHODS

Penetrating trauma patients at our American College of Surgeons-verified level 1 center with American Association for the Surgery of Trauma grade ≥3 abdominal solid organ injury (liver, spleen, kidney) were retrospectively screened (January 2017 to October 2021). Exclusions were age <18 y, transfers, death within <48 h, and nephrectomy/splenectomy within <4 h. Primary outcome was intervention triggered by dCTA. Statistical testing with ANOVA/chi-square compared outcomes between screened vs unscreened patients.

RESULTS

A total of 136 penetrating trauma patients met study criteria: 57 patients (42%) screened for PSA with dCTA and 79 (58%) unscreened. Liver injuries were most common (n = 41, 64% vs n = 55, 66%), followed by kidney (n = 21, 33% vs n = 23, 27%) and spleen (n = 2, 3% vs n = 6, 7%) (p = 0.48). Median American Association for the Surgery of Trauma grade of solid organ injury was 3 (3 to 4) across groups (p = 0.75). dCTA diagnosed 10 PSAs (18%) at a median of hospital day 5 (3 to 9). Among screened patients, dCTA triggered intervention in 17% of liver patients, 29% of kidney patients, and 0% of spleen-injured patients, for an overall yield of 23%.

CONCLUSIONS

Half of eligible penetrating high-grade solid organ injuries were screened for PSA with dCTA. dCTA identified a significant number of PSAs and triggered intervention in 23% of screened patients. dCTA did not diagnose any PSAs after splenic injury, although sample size hinders interpretation. To avoid missing PSAs and incurring their risk of rupture, universal screening of high-grade penetrating solid organ injuries may be prudent.

Impact of intravenous access site on attenuation for thoracic computed tomographic angiography: A time-matched, nested, case-control study

BACKGROUND

The objective of this study was to evaluate whether the choice of intravenous access (IVA) site affects aortic attenuation during thoracic computed tomographic angiography (T-CTA) and any associated risks with intravenous device placement.

METHODS

All T-CTA exams performed between 1/1/2013 and 8/14/2015 were retrospectively reviewed to identify those performed with contrast media injection via alternative (i.e. non-antecubital) IVA (n = 1769). Using time matching, antecubital IVA exams (n = 1769) were selected as controls. For each exam, attenuation was measured in the ascending aorta. Patient and technical data was subsequently collected from all 3538 patients included in this study. Multiple linear regression was used to determine if IVA site affected attenuation. Lastly, data related to extravasations for the entire T-CTA cohort were collected and compared.

RESULTS

Hand/wrist, arm, and central venous access device IVA were all equivalent to antecubital IVA in terms of attenuation (P = 0.579, P = 0.599, and P = 0.522 respectively). Forearm and intraosseous IVA had significantly higher attenuation (P = 0.010 and P = 0.002, respectively) than antecubital IVA. Right-sided IVA was associated with a small attenuation increase of 11 Hounsfield Units (P < 0.001) compared to left-sided IVA. In terms of extravasation, antecubital IVA was equivalent to hand/wrist, forearm, and upper arm IVA (P = 0.778, P = 0.060, and P = 0.090 respectively).

CONCLUSIONS

Satisfactory aortic attenuation achieved with non-antecubital IVA is equivalent to attenuation achieved with antecubital IVA for T-CTA imaging. The risk of contrast media extravasation in peripheral IVA devices was relatively low, however, appropriate IVA site selection should be considered an important factor for successful administration of contrast media for future imaging studies. This prevents undue harm to patients through preventable device failures when using a peripheral IV device in areas of high flexion/range of movements undergoing pressure injection for contrast media.

Bold-S Signs on Computed Tomography Angiography Are Sensitive Markers for Diagnosing Subcortical Hemorrhage Due to Dural Arteriovenous Fistulae on Emergent Admission

An optimal treatment strategy for subcortical hematomas caused by dural arteriovenous fistulae (dAVF) is important because of the high rebleeding rate. However, it is very difficult to diagnose that on admission. Therefore, an early sensitive predictive marker for subcortical hemorrhage caused by dAVF is necessary, especially during the first contact on admission. S-shaped dilated vessels around the hematoma (bold-S sign) on computed tomography angiography (CTA) performed during admission could be one such marker. Herein, we evaluated the characteristics of these vessels. Among 273 patients with intracerebral hemorrhage between April 2012 and March 2020, 67 patients with subcortical hematomas who underwent CTA on admission without arteriovenous malformations were included. The patients in the dAVF group (n = 7) showed fewer disturbances in consciousness, milder neurological deficits, and more frequent seizures than patients without dAVF (without dAVF group, n = 60). All patients in the dAVF group had dilated S-shaped vessels (2.59 ± 0.27 mm) around the hematomas, and only 20% of the patients in the without dAVF group had these vessels (1.69 ± 0.22 mm). The ratio of the ipsilateral S-shaped/contralateral largest vessels was 1.80 ± 0.29 in the dAVF group and 1.07 ± 0.16 in the group without dAVF. We called the dilated S-shaped vessels the "bold-S sign," with a cutoff ratio of 1.5. Bold-S sign findings are novel and help in diagnosing subcortical hematomas caused by dAVF on admission.

Role of cardiac imaging in acute chest pain

Chest pain is the second most common complaint in the emergency department. The need to diagnose the cause of chest pain in a timely manner and appropriately direct care is crucial. This article discusses the role of imaging in acute chest pain, after first differentiating chest pain into cardiac and non-cardiac causes with upfront clinical and biochemical assessment. The role of non-invasive imaging including point-of-care ultrasound, echocardiography, myocardial perfusion imaging, cardiac MRI, coronary computed tomography angiography and novel cardiac CT applications are discussed. Updates in the literature regarding the role of coronary plaque imaging in acute chest pain are reviewed, as are ongoing challenges and future directions. This includes a discussion on the yield of diagnostic testing in low-risk acute chest pain cohorts vs intermediate-high risk cohorts. The incremental value of further testing in the former is low, which is reflected in contemporary guidelines that discourage the use of costly diagnostic tests in these cohorts. In the latter cohort, emerging evidence has shown specifically the role coronary computed tomography angiography could play in reducing the need for invasive coronary angiography in selective patients where the true probability of acute coronary syndrome is thought to be low. Real-world considerations such as accessibility and affordability are also discussed in the paper because while guidelines offer clinicians the flexibility of evidence-based choice, physician decision must necessarily be made in consideration of real-world constraints.

The Utility of CTA in Pediatric Oropharyngeal Trauma: A Systematic Review and Meta-Analysis

OBJECTIVE(S)

To analyze the utility of computed tomography angiography (CTA) in identifying internal carotid artery (ICA) injury and reducing cerebrovascular accident (CVA) incidence in children presenting with normal neurologic exams after oropharyngeal trauma (OT).

DATA SOURCES

PubMed, Scopus, CINAHL, and Cochrane.

REVIEW METHODS

A systematic review and meta-analysis were performed following PRISMA guidelines. Of 1,185 studies screened, 95 studies of pediatric OT met inclusion criteria. Meta-analysis of proportions was performed.

RESULTS

A total of 1224 children with OT were analyzed. Excluding case reports, the weighted proportion of a CVA after OT was 0.31% (95% CI 0.06-0.93). If a child presented without neurologic deficits, 0.30% (95% CI 0.05-0.95) returned with new neurologic deficits. An ICA injury was identified in 0.89% (95% CI 0.16-2.74) of screening CTAs. No difference in CVA incidence was seen in children with screening CTA (0.52% [95% CI 0.02-2.15]) compared to children without screening CTA (0.42% [95% CI 0.06-1.37]). Patients who developed CVA had a higher proportion of injuries >2 cm, injuries at the posterior pillar or tonsil, and injuries with a writing utensil or popsicle stick compared to patients without CVA.

CONCLUSION

The proportion of children experiencing an ICA injury leading to CVA after sustaining OT is low. CTAs infrequently show ICA changes in children with normal neurological exams. Children who receive CTAs do not have a significantly lower incidence of CVAs than children who do not receive CTAs. Clinicians should weigh the risks and benefits of a CTA based on an individual child's presentation and discuss this with caregivers for shared decision-making. Laryngoscope, 133:25-37, 2023.

Lethal hemorrhage from iliac vein rupture complicating inferior vena cava thrombosis demonstrated by post-mortem CT angiography

Spontaneous iliac vein rupture is a rare cause of retroperitoneal hemorrhage that may present to the forensic pathologist. It has been reported in association with venous thrombosis, anatomical variants such as May-Thurner syndrome, and as a complication of a long-term indwelling IVC filter. It has a female predominance and most often occurs due to rupture of the left iliac vein. This is the first report of the use of post-mortem computed tomography (PMCT) and post-mortem computed tomography angiography (PMCTA) as an adjunct to a conventional autopsy to diagnose rupture of the left iliac vein causing retroperitoneal hemorrhage arising as a complication of an inferior vena cava (IVC) thrombus. We discuss the use of PMCTA as a useful tool in the diagnosis of vascular injury and how it can be used to assist the forensic pathologist. The use of PMCT with PMCTA is an invaluable adjunct to conventional autopsy to diagnose the site of vascular rupture.

[Imaging of coronary aneurysms in adults' coronary aneurysms]

Coronary aneurysms are rare and of various etiologies in adults. Natural history, modalities of management and clinical monitoring remain poorly known due to the lack of large studies and homogeneous diagnostic and follow-up criteria in the published data. Coronary angiography is, so far, the most common diagnostic tool but can overlook some partially thrombosed aneurysmal. Intracoronary imaging, particularly intravascular ultrasound, can differentiate aneurysms from pseudoaneurysms considered by some to be at greater risk of events, requiring a curative treatment. Intracoronary imaging can also help with etiological assessment and percutaneous treatment. With its growing use in the search for coronary atheromatous disease, coronary CT angiography has become a major diagnostic tool for coronary aneurysms. In addition, that it can incidentally detect coronary aneurysms, coronary CT angiography is particularly useful for giant aneurysms poorly visualized on coronary angiography or less well evaluated by intracoronary imaging. It specifies their relationship with adjacent anatomical structures. It is also a non-invasive modality of monitoring. These three imaging tools are currently the most relevant in current practice pending large studies evaluating the natural history of coronary aneurysms, with the identification of possible risk factors that could modify the management.

Computed Tomography Angiography Markers and Intraluminal Thrombus Morphology as Predictors of Abdominal Aortic Aneurysm Rupture

Background: Abdominal aortic aneurysm (AAA) is a complex vascular disease characterized by progressive and irreversible local dilatation of the aortic wall. Currently, the indication for repair is linked to the transverse diameter of the abdominal aorta, using computed tomography angiography imagery, which is one of the most used markers for aneurysmal growth. This study aims to verify the predictive role of imaging markers and underlying risk factors in AAA rupture. Methods: The present study was designed as an observational, analytical, retrospective cohort study and included 220 patients over 18 years of age with a diagnosis of AAA, confirmed by computed tomography angiography (CTA), admitted to Vascular Surgery Clinic of Mures County Emergency Hospital in Targu Mures, Romania, between January 2018 and September 2022. Results: Patients with a ruptured AAA had higher incidences of AH (p = 0.006), IHD (p = 0.001), AF (p < 0.0001), and MI (p < 0.0001), and higher incidences of all risk factors (tobacco (p = 0.001), obesity (p = 0.02), and dyslipidemia (p < 0.0001)). Multivariate analysis showed that a high baseline value of all imaging ratios markers was a strong independent predictor of AAA rupture (for all p < 0.0001). Moreover, a higher baseline value of DAmax (OR:3.91; p = 0.001), SAmax (OR:7.21; p < 0.001), and SLumenmax (OR:34.61; p < 0.001), as well as lower baseline values of DArenal (OR:7.09; p < 0.001), DACT (OR:12.71; p < 0.001), DAfemoral (OR:2.56; p = 0.005), SArenal (OR:4.56; p < 0.001), SACT (OR:3.81; p < 0.001), and SThrombusmax (OR:5.27; p < 0.001) were independent predictors of AAA rupture. In addition, AH (OR:3.33; p = 0.02), MI (OR:3.06; p = 0.002), and PAD (OR:2.71; p = 0.004) were all independent predictors of AAA rupture. In contrast, higher baseline values of SAmax/Lumenmax (OR:0.13; p < 0.001) and ezetimibe (OR:0.45; p = 0.03) were protective factors against AAA rupture. Conclusions: According to our findings, a higher baseline value of all imaging markers ratios at CTA strongly predicts AAA rupture and AH, MI, and PAD highly predicted the risk of rupture in AAA patients. Furthermore, the diameter of the abdominal aorta at different levels has better accuracy and a higher predictive role of rupture than the maximal diameter of AAA.

Plaque Burden and 1-Year Outcomes in Acute Chest Pain: Results From the Multicenter RAPID-CTCA Trial

BACKGROUND

In patients with stable chest pain, computed tomography (CT) plaque burden is an independent predictor of future coronary events.

OBJECTIVES

The purpose of this study was to determine whether plaque burden and characteristics can predict subsequent death or myocardial infarction in patients with acute chest pain.

METHODS

In a post hoc analysis of a multicenter trial of early coronary CT angiography, the authors performed quantitative plaque analysis to assess the association between primary endpoint of 1-year all-cause death or nonfatal myocardial infarction and the GRACE (Global Registry of Acute Coronary Events) score, presence of obstructive coronary artery disease, and plaque burden in 404 patients with suspected acute coronary syndrome.

RESULTS

Following the index event, 25 patients had a primary event that was associated with a higher GRACE score (134 ± 44 vs 113 ± 35; P = 0.012), larger burdens of total (46% [IQR: 43%-50%] vs 36% [IQR: 21%-46%]; P < 0.001), noncalcified (41% [IQR: 37%-%47] vs 33% [IQR: 20%-41%]; P < 0.001), and low-attenuation plaque (4.22% [IQR: 3.3%-5.68%] vs 2.14% [IQR: 0.5%-4.88%]; P < 0.001), but not obstructive coronary artery disease (P = 0.065). Total, noncalcified, and low-attenuation plaque burden were the strongest predictors of future events independent of GRACE score and obstructive coronary artery disease (P ≤ 0.002 for all). Patients with a low-attenuation burden above the median had nearly an 8-fold increased risk of the primary endpoint (HR: 7.80 [95% CI: 2.33-26.0]; P < 0.001), outperforming either a GRACE score of >140 (HR: 3.80 [95% CI :1.45-6.98]; P = 0.004) or obstructive coronary artery disease (HR: 2.07 [95% CI: 0.94-4.53]; P = 0.07).

CONCLUSIONS

In patients with suspected acute coronary syndrome, low-attenuation plaque burden is a major predictor of 1-year death or recurrent myocardial infarction. (Rapid Assessment of Potential Ischaemic Heart Disease With CTCA [RAPID-CTCA]; NCT02284191).

Right-to-left ventricle ratio determined by machine learning algorithms on CT pulmonary angiography images predicts prolonged ICU length of stay in operated chronic thromboembolic pulmonary hypertension

OBJECTIVE

Right-to-left ventricle diameter ratio (dRV/dLV) on CT pulmonary angiography (CTPA) is a predictor of outcomes in non-operated chronic thromboembolic pulmonary hypertension (CTEPH) patients. The purpose of this study is to evaluate the performance of a novel machine learning (ML) algorithm for dRV/dLV measurement in operated CTEPH patients and its association with post-operative outcomes.

METHODS

This retrospective study reviewed consecutive CTEPH patients who underwent pulmonary endarterectomy between 2013 and 2017. ML calculated dRV/dLV on pre-operative CTPA and compared with manual measures. Associations of dRV/dLV with patient characteristics and post-operative outcomes were evaluated including intensive care (ICU) and hospital length of stay (LOS) using multivariable linear regression analysis. Prolonged LOS was defined as greater than median.

RESULTS

ML segmented the ventricles in 99/125 (79%) patients. The most common cause of failure was misidentification of the moderator band as the interventricular septum (7.9%). Mean dRV/dLV by ML was 1.4 ± 0.4 and strongly correlated with manual measures (r = 0.9-0.96 p < 0.0001). dRV/dLV was moderately correlated with measures of pulmonary hypertension on right heart catheterization and RV dilatation on echocardiogram (r = 0.5-0.6, p < 0.0001). dRV/dLV ≥ 1.2 was associated with proximal Jamieson type disease (p = 0.032), longer cardiopulmonary bypass (p = 0.037), aortic cross-clamp (p = 0.022) and circulatory arrest (p < 0.001) at surgery and dRV/dLV ≥ 1.6 with post-operative ECMO (p = 0.006). dRV/dLV was independently associated with prolonged ICU LOS (OR = 3.79, 95% CI 1.1-13.06, p = 0.035).

CONCLUSION

dRV/dLV was associated with CTEPH severity and independently associated with prolonged ICU LOS. This CT parameter may therefore assist in perioperative planning. Further refinement of the ML algorithm or CTPA technique is required to avoid errors in ventricular segmentation.

ADVANCES IN KNOWLEDGE

Automated right-to-left ventricle ratio measurement by machine learning is feasible and is independently associated with outcome after pulmonary endarterectomy.

Factors influencing the safety of outpatient coronary CT angiography: a clinical registry study

OBJECTIVES

Since the safety of coronary CT angiography (CTA) is of great importance, especially with regard to widening indications and increasing morbidity, the aim of this study was to assess influencing factors.

METHODS

Patients undergoing coronary CTA in a third-generation dual-source CT in a radiological centre were included in a clinical registry. Up to 20 mg metoprolol was administered intravenously to attain a heart rate ≤65/min. Glyceryl trinitrate (GTN) was administered in doses of 0.8 mg and 0.4 mg. Blood pressure was measured before the administration and after the CTA.

RESULTS

Out of 5500 consecutive patients (3194 men, 62.3 (54.9-70.0) years), adverse events occurred in 68 patients (1.2%) with mild anaphylactoid reactions (0.4%), vasovagal symptoms (0.3%) and extravasation (0.3%) being most frequent. Anti-allergic drugs were given in 17 patients, atropine in 3 patients and volume in 1 patient. Drug administration resulted in a significant mean arterial pressure decline (96.0 (88.3-106.0) vs 108.7 (99.7-117.3) mmHg; p<0.001). Patients who suffered systolic blood pressure drops >20 mmHg or >40 mmHg were older (66.5 (58.6-73.3) vs 60.5 (53.6-68.3) years; 70.2 (63.3-76.5) vs 62.1 (54.7-69.6) years), more often male (65.1% vs 54.4%; 68.9% vs 57.3%) and had higher Agatston score equivalents (83.0 (2.0-432.0) vs 15.0 (0.0-172.0); 163.0 (16.3-830.8) vs 25.0 (0.0-220.0); all p<0.001). GTN dose reduction lowered the fraction of patients suffering from blood pressure drops >20 mmHg or >40 mmHg from 34.5% to 27.4% and from 6.1% to 3.5% (both p<0.001), respectively. The proportion of coronary segments with impaired image quality did not differ significantly.

CONCLUSIONS

Coronary CTA with intravenous beta-blocker administration is a safe procedure in an outpatient setting as adverse events are rare and mostly mild. Reduced GTN doses can further improve safety by lowering the rate of significant blood pressure drops, which occurred especially in elderly men with increased plaque burden.

TRIAL REGISTRATION NUMBER

NCT03815123.

Dynamic CT angiography is more accurate in diagnosing endoleaks than standard triphasic CT angiography and enables targeted embolization

PURPOSE

The primary objective was to compare the accuracy of dynamic CT angiography (d-CTA) with standardized triphasic contrast enhanced CT angiography (t-CTA) in diagnosing endoleak type after endovascular aortic repair (EVAR) using digital subtraction angiography (DSA) as reference standard. The secondary objective was to study the impact of d-CTA on image-fusion guided endoleak embolization.

MATERIALS AND METHODS

Retrospective review of patients who underwent d-CTA imaging after EVAR between March 2019 and July 2021 was performed. De-identified images were independently reviewed by two-two blinded readers to document endoleak type and target vessels. Impact of d-CTA-guided embolization was evaluated by number of planning angiograms, radiation exposure and accuracy of target vessel overlay.

RESULTS

During the study period, 52 patients underwent d-CTA, 19 had all three modalities available for analysis. DSA imaging confirmed 4(21.0%) type-I, 14(73.7%) type-II and 1(5.3%) type-III endoleak. Findings from d-CTA matched with DSA in 19/19 cases (100%), whereas t-CTA matched in 14/19 cases (73.7%). In type-II endoleaks, number of target vessels identified by d-CTA, t-CTA and DSA were 23, 17 and 16 respectively. Mean dose-length product from d-CTA and t-CTA was 1445±551 and 1612±530 mGy*cm (p=0.26). Nine patients underwent d-CTA-guided type-II endoleak embolization, using a median of 1(range:1-4) planning angiogram before embolization utilizing 21.6(±8.7)% of total procedural radiation dose. Target vessel overlay was accurate in 9/9(100%) cases.

CONCLUSION

Dynamic, time-resolved CTA is more accurate compared to standardized triphasic contrast enhanced CTA in diagnosing endoleak type after EVAR. In type-II endoleak, d-CTA better identified target vessels and enabled safe, targeted embolization.

Stroke and the Bovine Aortic Arch: Incidental or Deliberate? A Comparative Study and our Experience

AIM AND OBJECTIVES

We aimed to find the prevalence of bovine aortic arch in stroke and non-stroke patients and to study the relationship between bovine aortic arch and the occurrence of stroke.

MATERIALS AND METHODS

One hundred patients with and without stroke underwent computed tomography (CT) angiography of the thoracic aorta and its arch. Fifty diffusion-weighted magnetic resonance imaging (MRI)-confirmed anterior circulation stroke patients who had undergone digital subtraction angiography (DSA) afterward formed the case group. As controls, another 50 patients who had thoracic CT angiograms for disease other than stroke during this time period were randomly selected. Demographics and prevalence of bovine arch were compared between cases and controls. In the case group, demographics and prevalence of bovine arch variants and their relationship to stroke were studied.

RESULTS

Prevalence of bovine aortic arch variant in anterior circulation stroke was 22%, compared to 6% in non-stroke patients (P = 0.043). The bovine aortic arch was associated with the younger onset of stroke occurrence (P = 0.046). In the bovine arch group, the proportion of left-sided strokes (P = 0.022) and bilateral strokes (P < 0.00001) was significantly higher. As compared to type A (P = 0.140), type B bovine aortic arch had a better association (P = 0.092).

CONCLUSIONS

Bovine aortic arch is a risk factor for young-onset anterior circulation stroke. Bilateral and left-sided infarcts were more common. Endovascular procedures are difficult to perform through conventional routes, so brachioradial access is preferred.

Alternative vascular device for high-flow computed tomography angiography: ultrasound-guided long peripheral catheter (4 Fr × 10 cm)

INTRODUCTION

Radiological studies that require contrast media are common and useful in the emergency department. Alternatives have been proposed for the administration of contrast agent in patients with difficulty in the insertion of vascular access. Since 2017, our institution has used a 4-Fr × 10-cm-long peripheral catheter (Leadercath; Vygon) for venous insertion. Its ultrasound-guided insertion is carried out by emergency physicians. So far, there are no reports in the literature about the use of this long peripheral catheter for computed tomography angiography.

OBJECTIVE

To describe the experience with the said device, to point out the complications associated with it, and to evaluate it as an alternative way to gain vascular access for patients with limited venous access.

METHODS

An observational, analytical, and retrospective study was conducted. The study included patients who received an ultrasound-guided 4-Fr × 10-cm-long peripheral catheter (Leadercath; Vygon). Transparent, radiopaque, polyethylene, 18-gauge Leadercath from Vygon, sold as peripheral arterial catheter and sometimes used "off-label" as venous catheter with a flow capacity of up to 24 mL/min, was used. The flow capacity for gravity flow is 24 mL/s; with pump-driven flow, we achieved a flow infusion of 5-6 mL/s. Univariate analyses were performed. Normality was determined through the Shapiro-Wilk test.

RESULTS

In total, 172 patients met the inclusion criteria. Of them, 115 (67%) were female and the average age was 59 years. The main indication for performing the computed tomography angiography was the suspicion of pulmonary embolism (38.6%). The most frequent type of computed tomography angiography study was pulmonary tomography (88 patients, 51.5%). The contrast medium infusion rate was 6 mL/s in 51.5% (n = 88) of cases, 4.5 mL/s in 36.3%, and 5 mL/s in 12.3%. One adverse event occurred.

CONCLUSION

An 18-gauge-long peripheral catheter (4 Fr × 10 cm, Leadercath; Vygon) following specific protocols appears to be safe for conducting high-flow computed tomography studies in patients with limited venous access.

Application Value of CTA in the Computer-Aided Diagnosis of Subarachnoid Hemorrhage of Different Origins

Subarachnoid hemorrhage (SAH) is difficult to detect because of its circulation through subarachnoid space, which leads to a high rate of missed diagnosis. Based on the above background, the purpose of this study is to study the application value of brain CT angiography (CTA) in computer-aided diagnosis of subarachnoid hemorrhage with a wide range of brain digital subtraction angiography as a gold standard. This paper collected images and related medical records of 111 patients with spontaneous subarachnoid hemorrhage receiving brain CTA and DSA examinations from February 2015 to November 2019 in the neurology department of our hospital. In contrast to the number, position, length, width, and neck width of the causative aneurysm detected by DSA, we evaluated the diagnostic results of CTA and evaluated whether there was statistical difference between the two detectives of intracranial aneurysms. The results showed that the area under ROC curve of subtraction CTA and conventional CTA was 1.000 and 0.818, respectively, which indicated that the former had better display effect on internal carotid aneurysm (AUC > 0.9), while the latter had medium value (0.7 < AUC ≤ 0.9), and the difference was statistically significant (z = 2.390, p=0.017).

Cardiac computed tomography angiography in the paediatric population: Expert consensus from the Filiale de cardiologie pédiatrique et congénitale (FCPC) and the Société française d'imagerie cardiaque et vasculaire diagnostique et interventionnelle (SFICV)

This paper aims to provide a paediatric cardiac computed tomography angiography expert panel consensus based on the opinions of experts from the Société française d'imagerie cardiaque et vasculaire diagnostique et interventionnelle (SFICV) and the Filiale de cardiologie pédiatrique congénitale (FCPC). This expert panel consensus includes recommendations for indications, patient preparation, computed tomography angiography radiation dose reduction techniques and postprocessing techniques. We think that to realize its full potential and to avoid pitfalls, cardiac computed tomography angiography in children with congenital heart disease requires training and experience. Moreover, paediatric cardiac computed tomography angiography protocols should be standardized to acquire optimal images in this population with the lowest radiation dose possible, to prevent unnecessary radiation exposure. We also provide a suggested structured report and a list of acquisition protocols and technical parameters in relation to specific vendors.

Spontaneous Rectus Sheath Hematoma: Factors Predictive of Conservative Management Failure

PURPOSE

To evaluate radiographic, laboratory, and clinical factors associated with conservative management (CM) failure in spontaneous rectus sheath hematoma (RSH).

MATERIALS AND METHODS

Retrospective review of 72 patients with spontaneous RSH between 2006 and 2017 was performed. Patients were initially managed conservatively and then divided into 2 groups based on decision to embolize. No differences were found between embolization (n = 32) and CM (n = 40) groups in age (67.5 vs 69.5 y; P = .79), sex (31% vs 38% male; P = .58), body mass index (27.7 vs 25.7 kg/m²; P = .20), or medical comorbidities. Univariate analyses compared initial hemoglobin level, change in hemoglobin level, coagulation parameters, transfusion requirements, hematoma volume, and active extravasation on computed tomographic (CT) angiography between groups. Multivariable logistic regression identified factors predictive of CM failure. A scoring system was then created to predict CM failure.

RESULTS

CM failed in 32 of 72 patients. Multivariable regression identified active extravasation on CT angiography (P = .02), hematoma volume (P = .01), and packed red blood cell (pRBC) transfusion of ≥ 4 U (P = .03) as predictors of embolization. A scoring system using these factors along with maximum rate of hemoglobin decrease yielded a sensitivity of 100% and specificity of 98% in determining need for embolization.

CONCLUSIONS

CM for RSH was more likely to fail in patients with active extravasation on CT angiography, larger hematoma volume, pRBC transfusion of ≥ 4 U, and higher rate of hemoglobin decrease. Using these parameters, a scoring system was created that achieved high sensitivity and specificity in identifying patients who would require embolization.

Association of the incidence of venous air embolism on coronary computed tomography angiography with the intravenous access route preparation process

Venous air embolism (VAE) can be observed in the right heart system on contrast-enhanced computed tomography (CT), following injection of contrast media with a power injector system. Although most VAEs are mostly asymptomatic, they may result in paradoxical air embolism (PAE).To evaluate whether the incidence of VAE on coronary CT angiography is associated with the process of preparation of the intravenous access route.We retrospectively evaluated 692 coronary CT examinations at 3 institutions. Trained CT nurses placed an intravenous cannula in the forearm. Tubes connected to the cannula were prepared in the following ways: A, using an interposed three-way cock and a 20-mL syringe filled with normal saline to collect air contamination in the tube; B, through direct connection to the power injector system without the interposed 3-way cock; and C, using an interposed three-way cock and a 100-mL normal saline drip infusion bottle system to keep the tube patent. The incidence and location of VAE and preparation of intravenous injection were assessed.The overall incidence of VAE was 55.3% (383/692), most frequently observed in the right atrium (81.5%, 312/383). Its incidence varied significantly across the 3 techniques (A: 21.6% (35/162), B: 63.2% (237/375) and C: 71.6% (111/155); P < .001). No patient demonstrated any symptom associated with VAE.Using a 3-way cock with syringe demonstrated the lowest incidence of VAE on coronary CT angiography. It is thus recommended to reduce potential complication risks related to intravenous contrast media injection.

Intra-arterial catheter-directed CT angiography for assessment of endovascular aortic aneurysm repair

OBJECTIVE

To compare the efficacy and safety as well as associated image quality of catheter-directed CT angiography (CCTA) with a low dose of iodine contrast agent compared to intravenous CTA in patients undergoing endovascular aortic aneurysm repair (EVAR).

METHODS

Retrospective data analysis of 92 patients undergoing EVAR between January 2009 and December 2017 was performed. Patients were divided in two groups; those receiving CTA (n = 59) after intravenous contrast agent application and those receiving CCTA (n = 33) via an intraarterial catheter placed in the descending aorta. Demographic and cardiovascular risk factors as well as renal function parameters before, immediately after and 6-60 months after EVAR were evaluated. As primary endpoint, changes in serum creatinine levels in the two groups were evaluated. Secondary endpoints encompassed complications associated with intraarterial catheter placement. Objective (signal-to-noise ratios) and subjective image quality (5-point Likert scale) were compared.

RESULTS

Amount of contrast medium was significantly lower in CCTA compared to i.v. CTA (23 ± 7 ml vs. 119 ± 15 ml, p<0.0001). Patients undergoing catheter-directed CTA had higher baseline creatinine values compared to the group with intravenous iodine application (1.9 ± 0.6 mg/dl vs. 1.3 ± 0.5 mg/dl; p<0.0001). Follow-up serum creatinine levels however did not show significant alterations between the two groups (1.9 ± 0.4 mg/dl vs. 1.3 ± 0.5 mg/dl). No major complications were detected in the CCTA group. Signal-to-noise ratio (SNR) was comparable between i.v. CTA and CCTA (8.5 ± 4.6 vs. 7.7 ± 4.0; p = 0.37) and subjective image similarly revealed no differences with a good interobserver agreement (ICC = 0.647).

CONCLUSIONS

Catheter-directed CTA is safe and provides comparable image quality with a substantial retrenchment of the needed amount of iodine-based contrast medium. However, no benefit of the reduced contrast medium protocol with respect to renal function was observed.

Comparison of sequential and high-pitch-spiral coronary CT-angiography: image quality and radiation exposure

New protocols for coronary computed tomography angiography (CCTA) could lower the radiation dose for patients but influence the image quality. To compare image quality and radiation exposure in step-and-shoot CCTA and high-pitch spiral CCTA. Fifty-nine pairs of patients matched for weight, height, sex and heart rate were included in this study (74 m, 44 f, average age 60 years, age range 29-94 years). Step-and-shoot CCTA and high-pitch spiral CCTA was performed on a third generation dual-source CT in equally sized patient groups. The signal-to-noise ratio (SNR) in the ascending aorta and the coronary arteries were determined for each dataset. Image quality was rated using a five-point scale. We used the t-test for paired samples to compare SNR and effective dose, and the Wilcoxon test to compare image quality scores. Mean effective dose for the step-and-shoot protocol (4.15 ± 3.07 mSv) was significantly higher in comparison to the high-pitch spiral protocol (1.2 ± 0.69 mSv; p < 0.0001). Mean SNR was higher with the step-and-shoot protocol compared to the high-pitch spiral protocol in the aorta, in the left main and peripheral coronary arteries (p < 0.01), in the proximal right coronary artery (p = 0.027). Image quality scores were significantly better for the step-and-shoot protocol (p = 0.0003). Step-and-shoot CCTA has significantly better SNR and overall image quality compared to high-pitch spiral CCTA, but with a mean effective dose more than thrice as high.

A novel ultrafast-low-dose computed tomography protocol allows concomitant coronary artery evaluation and lung cancer screening

BACKGROUND

Cardiac computed tomography (CT) is often performed in patients who are at high risk for lung cancer in whom screening is currently recommended. We tested diagnostic ability and radiation exposure of a novel ultra-low-dose CT protocol that allows concomitant coronary artery evaluation and lung screening.

METHODS

We studied 30 current or former heavy smoker subjects with suspected or known coronary artery disease who underwent CT assessment of both coronary arteries and thoracic area (Revolution CT, General Electric). A new ultrafast-low-dose single protocol was used for ECG-gated helical acquisition of the heart and the whole chest. A single IV iodine bolus (70-90 ml) was used. All patients with CT evidence of coronary stenosis underwent also invasive coronary angiography.

RESULTS

All the coronary segments were assessable in 28/30 (93%) patients. Only 8 coronary segments were not assessable in 2 patients due to motion artefacts (assessability: 98%; 477/485 segments). In the assessable segments, 20/21 significant stenoses (> 70% reduction of vessel diameter) were correctly diagnosed. Pulmonary nodules were detected in 5 patients, thus requiring to schedule follow-up surveillance CT thorax. Effective dose was 1.3 ± 0.9 mSv (range: 0.8-3.2 mSv). Noteworthy, no contrast or radiation dose increment was required with the new protocol as compared to conventional coronary CT protocol.

CONCLUSIONS

The novel ultrafast-low-dose CT protocol allows lung cancer screening at time of coronary artery evaluation. The new approach might enhance the cost-effectiveness of coronary CT in heavy smokers with suspected or known coronary artery disease.

[The choice of diagnostic modality for acute pulmonary embolism]

The diagnosis of pulmonary embolism (PE) relies on clinical assessment, D-dimer test and diagnostic imaging. Modern CT pulmonary angiography (CTPA), ventilation/perfusion  single-photon emission computed tomography (SPECT) and SPECT/CT are rather equal in terms of sensitivity, specificity and inconclusive results for the diagnosis of PE, outper-forming planar lung scintigraphy. Furthermore, SPECT/CT and CTPA can both provide important information regarding differential diagnoses. Thus, the choice of primary diag-nostic modality relies on local expertise, availability and special circumstances like radiation dose, contraindications and the clinical urgency.

Rationale and design of the worldwide prospective multicenter registry on radiation dose estimates of cardiac CT angiography in daily practice in 2017 (PROTECTION VI)

BACKGROUND

Cardiac computed tomography angiography (cardiac CTA) is an increasingly used versatile imaging method to evaluate coronary and cardiac morphology. Owing to improvements in technology, image quality has continuously improved over the last 10-20 years. At the same time, numerous non-randomized and randomized studies have been performed to reduce the associated radiation exposure. Currently, it is unclear if the advances in technology and knowledge about radiation reduction translated into reduced levels of cardiac CTA radiation dose in daily clinical practice as well as a wide utilization of dose-saving strategies.

METHODS

The PROTECTION VI study is a multicenter, prospective, worldwide registry designed to evaluate radiation dose exposure, utilization of dose-saving strategies and diagnostic image quality during cardiac CTA in current daily practice. Assessment of image quality will be addressed by the evaluation of diagnostic image quality at the local study site and the calculation of quantitative image quality parameters in an imaging core laboratory. Above 4000 patients will be enrolled from approximately 70 sites in Europe, North America, South America, Asia and Australia. The study will analyze median radiation dose levels, image quality, frequency of use and efficacy of algorithms for dose reduction, and patient and study-related predictors associated with radiation dose.

CONCLUSIONS

The PROTECTION VI study is designed to provide a reliable estimate of current radiation dose for cardiac CTA and to assess the potential for additional dose reductions.

German cardiac CT registry: indications, procedural data and clinical consequences in 7061 patients undergoing cardiac computed tomography

Cardiac computed tomography permits quantification of coronary calcification as well as detection of coronary artery stenoses after contrast enhancement. Moreover, cardiac CT offers high-resolution morphologic and functional imaging of cardiac structures which is valuable for various structural heart disease interventions and electrophysiology procedures. So far, only limited data exist regarding the spectrum of indications, image acquisition parameters as well as results and clinical consequences of cardiac CT examinations using state-of-the-art CT systems in experienced centers. Twelve cardiology centers with profound expertise in cardiovascular imaging participated in the German Cardiac CT Registry. Criteria for participation included adequate experience in cardiac CT as well of the availability of a 64-slice or newer CT system. Between 2009 and 2014, 7061 patients were prospectively enrolled. For all cardiac CT examinations, patient parameters, procedural data, indication and clinical consequences of the examination were documented. Mean patient age was 61 ± 12 years, 63% were males. The majority (63%) of all cardiac CT examinations were performed in an outpatient setting, 37% were performed during an inpatient stay. 91% were elective and 9% were scheduled in an acute setting. In most examinations (48%), reporting was performed by cardiologists, in 4% by radiologists and in 47% of the cases as a consensus reading. Cardiac CT was limited to native acquisitions for assessment of coronary artery calcification in 9% of patients, only contrast-enhanced coronary CT angiography was performed in 16.6% and combined native and contrast-enhanced coronary CT angiography was performed in 57.7% of patients. Non-coronary cardiac CT examinations constituted 16.6% of all cases. Coronary artery calcification assessment was performed using prospectively ECG-triggered acquisition in 76.9% of all cases. The median dose length product (DLP) was 42 mGy cm (estimated effective radiation dose of 0.6 mSv). Coronary CT angiography was performed using prospectively ECG-triggered acquisition in 77.3% of all cases. Tube voltage was 120 kV in 67.8% of patients and 100 kV in 30.7% of patients, with a resultant median DLP of 256 mGy cm (estimated effective dose of 3.6 mSv). Clinical consequences of cardiac CT were as follows: in 46.8% of the cases, invasive coronary angiography could be avoided; ischemia testing was recommended in 4.7% of the cases, invasive coronary angiography was recommended in 16.4% of the cases and change in medication in 21.6% of the examinations. Cardiac CT is performed in the majority of patients for non-invasive evaluation of the coronary arteries. CT frequently resulted in medication change, and otherwise planned downstream testing including invasive angiography could be avoided in a high percentage of patients. Radiation exposure in experienced centers is relatively low.

Safety of multidetector computed tomography pulmonary angiography to exclude pulmonary embolism in patients with a likely pretest clinical probability

Essentials Safety of computed tomography (CTPA) to exclude pulmonary embolism (PE) in all patients is debated. We analysed the outcome of PE-likely outpatients left untreated after negative CTPA alone. The 3-month venous thromboembolic risk in these patients was very low (0.6%; 95% CI 0.2-2.3). Multidetector CTPA alone safely excludes PE in patients with likely clinical probability.

SUMMARY

Background In patients with suspected pulmonary embolism (PE) classified as having a likely or high pretest clinical probability, the need to perform additional testing after a negative multidetector computed tomography pulmonary angiography (CTPA) finding remains a matter of debate. Objectives To assess the safety of excluding PE by CTPA without additional imaging in patients with a likely pretest probability of PE. Patients/Methods We retrospectively analyzed patients included in two multicenter management outcome studies that assessed diagnostic algorithms for PE diagnosis. Results Two thousand five hundred and twenty-two outpatients with suspected PE were available for analysis. Of these 2522 patients, 845 had a likely clinical probability as assessed by use of the simplified revised Geneva score. Of all of these patients, 314 had the diagnosis of PE excluded by a negative CTPA finding alone without additional testing, and were left without anticoagulant treatment and followed up for 3 months. Two patients presented with a venous thromboembolism (VTE) during follow-up. Therefore, the 3-month VTE risk in likely-probability patients after a negative CTPA finding alone was 2/314 (0.6%; 95% confidence interval [CI] 0.2-2.3%). Conclusions In outpatients with suspected PE and a likely clinical probability as assessed by use of the simplified revised Geneva score, CTPA alone seems to be able to safely exclude PE, with a low 3-month VTE rate, which is similar to the VTE rate following the gold standard, i.e. pulmonary angiography.

Effects of Radiation Exposure on the Cost-Effectiveness of CT Angiography and Perfusion Imaging in Aneurysmal Subarachnoid Hemorrhage

BACKGROUND AND PURPOSE

CT angiography and perfusion imaging is an important prognostic tool in the management of patients with aneurysmal subarachnoid hemorrhage. The purpose of this study was to perform a cost-effectiveness analysis of advanced imaging in patients with SAH, incorporating the risks of radiation exposure from CT angiography and CT perfusion imaging.

MATERIALS AND METHODS

The risks of radiation-induced brain cancer and cataracts were incorporated into our established decision model comparing the cost-effectiveness of CT angiography and CT perfusion imaging and transcranial Doppler sonography in SAH. Cancer risk was calculated by using National Cancer Institute methodology. The remaining input probabilities were based on literature data and a cohort at our institution. Outcomes were expected quality-adjusted life years gained, costs, and incremental cost-effectiveness ratios. One-way, 2-way, and probabilistic sensitivity analyses were performed.

RESULTS

CT angiography and CT perfusion imaging were the dominant strategies, resulting in both better health outcomes and lower costs, even when incorporating brain cancer and cataract risks. Our results remained robust in 2-way sensitivity analyses varying the prolonged latency period up to 30 years, with either brain cancer risk up to 50 times higher than the upper 95% CI limit or the probability of cataracts from 0 to 1. Results were consistent for scenarios that considered either symptomatic or asymptomatic patients with SAH. Probabilistic sensitivity analysis confirmed our findings over a broad range of selected input parameters.

CONCLUSIONS

While risks of radiation exposure represent an important consideration, CT angiography and CT perfusion imaging remained the preferred imaging compared with transcranial Doppler sonography in both asymptomatic and symptomatic patients with SAH, with improved health outcomes and lower health care costs, even when modeling a significantly higher risk and shorter latency period for both cataract and brain cancer than that currently known.

Incidence of persistent renal dysfunction after contrast enhanced coronary CT angiography in patients with suspected coronary artery disease

Contrast-induced nephropathy (CIN) is a potentially serious complication of contrast agents used in computed tomography angiography (CTA). The aim of this study was to evaluate whether persistent renal dysfunction occurs in patients undergoing coronary CTA for suspected stable coronary artery disease (CAD). From a cohort of 957 patients undergone coronary CTA, we identified 402 patients with plasma creatinine levels collected before and within 6 months after CTA. According to the definition of CIN, patients with a ≥25 % increase in plasma creatinine after CTA were evaluated. The post-CTA measurements in 402 patients (195 men, age 62.9 ± 9.3 years) were performed at a median of 99 days after CTA. On average, there was no change in plasma creatinine level between the pre- and post-CTA measurements (75.8 ± 16.0 and 75.7 ± 16.4 µmol/L, respectively; P = 0.63) but both increases and decreases were commonly detected. Fourteen (3.5 %) patients had a ≥25 % increase in plasma creatinine levels after CTA. A more detailed evaluation of these patients revealed that in 4 patients the increase was explained by other morbidities, whereas in 9 patients the creatinine level returned to the previous levels at later follow-up (median time to normalization: 311 days). Only in 1 (0.2 %) remaining patient, there was a persistent increase in plasma creatinine level, possibly related to the iodine contrast agent exposure. Alterations in plasma creatinine concentration occur frequently. Persistent renal dysfunction attributable to iodine contrast agent exposure is rare in patients referred to coronary CTA for suspected CAD.

[Results of endovascular treatment of patients with type C and D lesions of the aortoiliac segment according to the TASC II classification]

Presented herein are the results of endovascular interventions carried out in patients with occlusive lesions of the terminal portion of the aorta and iliac arteries (types C and D according to the TASC II classification). The study comprised a total of 45 subjects with type C and D lesions. The technical success rate in the group of patients with type C lesions amounted to 100% and in the group of those with type D lesions to 92.8%. One-year primary patency of iliac arteries after the endovascular intervention was assessed in 40 patients and amounted to 100% for type C lesions and to 92.8% for type D lesions. The obtained findings are strongly suggestive of a possibility of extending the indications for endovascular surgical interventions in management of patients with type C and D lesions, which makes it possible to achieve good immediate and remote results. This type of treatment may be regarded as a method of choice before further considering feasibility of an open surgical intervention.