Catheter-based Angiography Research Articles

Assessment of Cerebral Vasodilatory Capacity as Part of Catheter-Based Cerebral Angiography.

Cerebral vasodilatory capacity assessment for risk stratification in patients with extracranial arterial stenosis or occlusion may be useful. We describe a new method that assesses cerebral vasodilatory capacity as part of catheter-based cerebral angiography. We prospectively assessed regional cerebral blood volume (rCBV) in the arterial distribution of interest using a controlled contrast injection in the common carotid or the subclavian arteries. rCBV maps were created using a predefined algorithm based on contrast distribution in the venous phase (voxel size: .466 mm3 ). rCBV maps were acquired again after selective administration of intra-arterial nicardipine (2.0 mg) distal to the stenosis. Two independent observers graded the change in rCBV in 10 predefined anatomical regions within the tributaries of the artery of interest (0 = reduction, 1 = no change, 2 = increase) and total rCBV change scores were summated. Twenty-five patients with internal carotid artery stenosis (n = 18; 0-90% in severity) or extracranial vertebral artery stenosis (n = 7; 0-100% in severity) were assessed. There was an increase in rCBV in a tributary of the artery of interest in 18 of 25 after intra-arterial nicardipine (mean score: 11.98; range 0-19.5). There was no change or decrease in rCBV in 7 of 25 patients. The mean rCBV change score was similar in patients with an assessment of internal carotid artery or vertebral artery distributions (12.2 ± 5.3; 11.4 ± 2.5; P = .68). Selective vasodilatory response to intra-arterial nicardipine in the affected arterial distribution during catheter-based cerebral angiography may provide new data for risk stratification.

Stereoelectroencephalography in epilepsy, cognitive neurophysiology, and psychiatric disease: safety, efficacy, and place in therapy.

For patients with drug-resistant epilepsy, surgical intervention may be an effective treatment option if the epileptogenic zone (EZ) can be well localized. Subdural strip and grid electrode (SDE) implantations have long been used as the mainstay of intracranial seizure localization in the United States. Stereoelectroencephalography (SEEG) is an alternative approach in which depth electrodes are placed through percutaneous drill holes to stereotactically defined coordinates in the brain. Long used in certain centers in Europe, SEEG is gaining wider popularity in North America, bolstered by the advent of stereotactic robotic assistance and mounting evidence of safety, without the need for catheter-based angiography. Rates of clinically significant hemorrhage, infection, and other complications appear lower with SEEG than with SDE implants. SEEG also avoids unnecessary craniotomies when seizures are localized to unresectable eloquent cortex, found to be multifocal or nonfocal, or ultimately treated with stereotactic procedures such as laser interstitial thermal therapy (LITT), radiofrequency thermocoagulation (RF-TC), responsive neurostimulation (RNS), or deep brain stimulation (DBS). While SDE allows for excellent localization and functional mapping on the cortical surface, SEEG offers a less invasive option for sampling disparate brain areas, bilateral investigations, and deep or medial targets. SEEG has shown efficacy for seizure localization in the temporal lobe, the insula, lesional and nonlesional extra-temporal epilepsy, hypothalamic hamartomas, periventricular nodular heterotopias, and patients who have had prior craniotomies for resections or grids. SEEG offers a valuable opportunity for cognitive neurophysiology research and may have an important role in the study of dysfunctional networks in psychiatric disease and understanding the effects of neuromodulation.

Yield of diagnostic imaging in atraumatic convexity subarachnoid hemorrhage

IntroductionAtraumatic convexity subarachnoid hemorrhage is a subtype of spontaneous subarachnoid hemorrhage that often presents a diagnostic challenge. Common etiologies include cerebral amyloid angiopathy, vasculopathies, and coagulopathy; however, aneurysm is rare....

Patient-Friendly Summary of the ACR Appropriateness Criteria: Imaging of Mesenteric Ischemia

Mesenteric ischemia is a condition resulting from decreased blood supply to the mesenteric organs, primarily the small and large intestines. This can happen acutely (suddenly) from a blood clot or chronically (over time) from atherosclerosis (plaque buildup in the arteries). Acute mesenteric ischemia requires fast diagnosis to help prevent tissue death. CT angiography (CTA) is a CT scan with contrast timed to show the arteries. CTA is usually appropriate to confirm the diagnosis of mesenteric ischemia. CT with contrast in venous timing may be appropriate in conjunction with the CTA to assess the veins and organs, such as the bowel, for signs of tissue death. Catheter-based arteriography may be appropriate in addition to CTA to diagnose a blocked artery, treat the blockage if appropriate, or help plan for surgery. MR angiography (MRA) may be appropriate if CTA is not performed but takes longer and provides less information than CTA. Ultrasound and abdominal radiography (x-ray) have limited use in acute mesenteric ischemia situations. Chronic mesenteric ischemia is less time sensitive. Although ultrasound may be appropriate to screen patients, CTA and MRA are the most appropriate diagnostic tools and can be used together to provide complementary views of blood vessels. CTA is the most accurate imaging test for grading the degree of artery blockages. CT with contrast in venous timing may be performed in conjunction with the initial CTA scan to assess the veins and organs, such as the bowel. Catheter-based angiography may be appropriate to guide treatment and determine whether surgery is required. See the full appropriateness criteria for this topic at https://acsearch.acr.org/docs/70909/Narrative/.

Utility of diagnostic cerebral angiography in the management of suspected central nervous system vasculitis

Vasculitis of the central nervous system is a rare and poorly understood disease of the brain and spinal cord. Cerebral angiography is the radiological gold standard for diagnosis in patients with compatible clinical findings. However, advances in the quality of noninvasive neuroimaging techniques of cerebral and spinal vasculature such as magnetic resonance angiography (MRA) and computed tomography angiography (CTA) may obviate the need for invasive catheter angiography. We reviewed our institutional experience at Jackson Memorial Hospital between 2011 and 2016 to assess the utility of performing a cerebral digital subtraction angiogram (DSA) in the management of suspected vasculitis. In 16 (59%) of the 27 patients who underwent both noninvasive imaging and DSA, neither imaging studies showed any evidence of vasculitis. Despite these negative studies, 2 patients were treated empirically with immunosuppressants based on clinical symptoms and laboratory findings. 10 (37%) patients demonstrated irregularities on MRA and findings were confirmed by DSA in 6 of these patients. All 6 of these patients were treated, however, 2 of the 4 patients with abnormal MRA and normal DSA were also started on immunosuppressive therapy despite negative DSA. In conclusion, invasive catheter-based angiography may be of limited benefit in the diagnosis and management of PCNSV when considered in the context of clinical and laboratory findings and MRA or CTA results. Further large studies are necessary to determine whether non-invasive imaging can replace DSA.

Contemporary considerations for the use of cardiovascular magnetic resonance imaging during pregnancy.

Cardiovascular imaging during pregnancy is frequently used to help direct diagnosis and management for women with known or suspected cardiac disease. Although echocardiography is the most commonly used imaging modality in pregnancy, cardiovascular magnetic resonance imaging is an important and increasingly used tool, which can provide complementary, and oftentimes incremental, information regarding cardiovascular anatomy, ventricular function, and vascular flows. Advantages of cardiovascular magnetic resonance imaging over echocardiography and other imaging techniques include superior reproducibility, excellent cross-sectional evaluation of cardiac structures, high spatial resolution, and lack of ionizing radiation (a limitation of computed tomography and conventional catheter-based angiography). Cardiovascular magnetic resonance imaging in the absence of gadolinium-based contrast agents poses no known risk to the mother or fetus and its applications in pregnancy are expanding. Clinicians should be familiar with the role of cardiovascular magnetic resonance imaging in pregnancy to optimize and enhance care for mothers with heart disease.

Abstract WP22: A New Technique for the Assessment of Cerebral Vasodilatory Capacity as Part of Catheter-Based Cerebral Angiography

Background: Cerebral vasodilatory capacity assessment for risk stratification in patients with extracranial arterial stenosis or occlusion may be useful. We describe a new method that assesses cerebral vasodilatory capacity as part of catheter-based cerebral angiography. Methods: We prospectively assessed regional cerebral blood volume (rCBV) in the arterial distribution of interest using a controlled contrast injection in the common carotid or the subclavian arteries. rCBV maps were created using a predefined algorithm based on contrast distribution in the venous phase (voxel size 0.466 mm 3 ). rCBV maps were acquired again after selective administration of intra-arterial nicardipine (2.5 mg) distal to the stenosis. Two independent observers graded the change in rCBV in 10 predefined anatomical regions within the tributaries of the artery of interest (0=reduction, 1=no change, 2=increase) and total rCBV change scores were summated. The rCBV score values were averaged between the two observers for each patient. Mean arterial pressure was monitored at baseline and at 1 minute intervals post nicardipine administration for 5 minutes. Results: Twenty-five patients with internal carotid artery stenosis (n=18; 0%-90% in severity) or extracranial vertebral artery stenosis (n=7; 0%-100% in severity) were assessed. There was an increase in rCBV in a tributary of the artery of interest in 18 of 25 after intra-arterial nicardipine (mean score 11.98; range 0-19.5). There was no change or decrease in rCBV in 7 of 25 patients. The mean rCBV change score was similar in patients with assessment of internal carotid artery or vertebral artery distributions (12.2 ± 5.3; 11.4 ± 2.5; p=0.68 by ANOVA). There was an average (±SD) reduction of mean arterial pressure of 14mmHg ± 7.5 after intra-arterial nicardipine. There was no correlation between the magnitude of mean arterial pressure reduction post nicardipine (regression coefficient -0.13; p=0.38) or between the severity of stenosis (regression coefficient -0.04; p=0.29) and rCBV change scores. Conclusions: We describe a new technique for selective assessment of cerebral vasodilatory response in the affected arterial distribution during catheter-based cerebral angiography.

First International Consensus on the diagnosis and management of fibromuscular dysplasia.

This article is a comprehensive document on the diagnosis and management of fibromuscular dysplasia (FMD), which was commissioned by the working group 'Hypertension and the Kidney' of the European Society of Hypertension (ESH) and the Society for Vascular Medicine (SVM). This document updates previous consensus documents/scientific statements on FMD published in 2014 with full harmonization of the position of European and US experts. In addition to practical consensus-based clinical recommendations, including a consensus protocol for catheter-based angiography and percutaneous angioplasty for renal FMD, the document also includes the first analysis of the European/International FMD Registry and provides updated data from the US Registry for FMD. Finally, it provides insights on ongoing research programs and proposes future research directions for understanding this multifaceted arterial disease.

Visceral Fibromuscular Dysplasia: From asymptomatic disorder to emergency.

Fibromuscular dysplasia (FMD) is an idiopathic, segmental, non-atherosclerotic and non-inflammatory disease of the musculature of arterial walls, leading to stenosis of small and medium-sized arteries, mostly involving renal and cervical arteries. As a result of better and more systematic screening, it appears that involvement of the splanchnic vascular bed is more frequent than originally assumed. We review epidemiology, pathogenesis, clinical picture as well as diagnosis and treatment of visceral artery (VA) FMD. The clinical picture is very diverse, and diagnosis is based on CT-, MR- or conventional catheter-based angiography. Involvement of VAs generally occurs among patients with multi-vessel FMD. Therefore, screening for VA FMD is advised especially in renal artery (RA) FMD and in case of aneurysms and/or dissections. Treatment depends on the clinical picture. However, the level of evidence is low, and much of the common practice is extrapolated from visceral atherosclerotic disease.

Migraine and Non‐Migraine Headaches Following Diagnostic Catheter‐Based Cerebral Angiography

No reliable estimates of headaches following catheter-based cerebral angiography are available. We performed an observational cohort study to ascertain the frequency and type ofheadaches following catheter-based cerebral angiography. Consecutive patients who underwent cerebral angiography through the transfemoral (or infrequently radial) route were included. Each patient underwent a brief neurological assessment after the procedure and more detailed assessment was performed if any patient reported occurrence of a headache. The headaches were classified as migraine if the diagnostic criteria specified by International Headache Society were met. The headache severity was classified using a visual numeric rating scale and time to reach pain free status for 2 consecutive hours was ascertained. Migraine headaches occurred in 5 (3.1%, 95% confidence interval [CI] 1.0-7.2%) of 158 patients who underwent cerebral angiography. The median severity of migraine headaches was 10/10 and time to resolution of headaches was 120 minutes (range 60-360 minutes). Migraine headaches occurred in 4 (18.1%, 95% CI 5.2-40.3%) of 22 patients with a history of migraine and 4 (23.5%, 95% CI 6.8-50%) of 17 patients with regular migraine headaches (≥1 episodes per month). Headaches occurred in 6 (3.8%, 95%CI 1.8-8.0%) patients who did not meet the criteria for migraine headaches. We provide occurrence rates of migraine headaches, an under-recognized adverse event, in patients undergoing catheter-based cerebral angiography.

Outcomes of upper extremity interventions for chronic critical ischemia

BackgroundCritical hand ischemia owing to below-the-elbow atherosclerotic occlusive disease is relatively uncommon. The aim of this study was to examine the outcomes in patients presenting with critical ischemia owing to below-the-elbow arterial atherosclerotic disease who underwent nonoperative and operative management. MethodsA database of patients undergoing operative and nonoperative management for symptomatic below-the-elbow atherosclerotic disease between 2006 and 2016 was retrospectively queried. Patients with critical ischemia (tissue loss and rest pain) were identified. Three management groups were identified: no revascularization (None), endovascular revascularization (Endo), and open revascularization by bypass (Bypass). Patients with acute embolism, active vasculitis, end-stage renal disease, ipsilateral dialysis access complications of steal, and ipsilateral trauma were excluded. ResultsOne hundred eight patients (56% male; average age, 59 years) presented with symptomatic below-the-elbow disease: 93% presented with digital ulceration and the remainder with rest pain. Eighty-one percent had diabetes and 41% had chronic renal insufficiency (not on dialysis). All underwent catheter-based angiography. Fifty-three patients (49%) had no intervention and subsequently were committed to wound care; 26 of these required no further intervention, 10 had an interval palmar sympathectomy, and 17 underwent either a phalanx or digital amputation. Thirty-four patients (31%) underwent an endovascular intervention with a median of 1.5 vessels (ulnar, radial, or interosseous arteries) intervened on. Technical success was achieved in 29 patients (85%). Of the five technical failures, two went on to bypass, one had a focal endarterectomy and patch angioplasty, and one was treated conservatively. Ten patients in the Endo group required either a phalanx or digital amputation. Twenty-one patients (19%) underwent a saphenous vein bypass (reversed or nonreserved) to the radial in 12 and the ulnar in 11 limbs. In follow-up, 11 patients underwent open or endovascular intervention to maintain patency of the bypass. There were nine phalanx or digital amputations in the Bypass group. No below-the-elbow or above-the-elbow amputations were performed within 30 days. The wound healing rate without amputation was 78% (85 of 108). The predictors of wound healing were technical success of the revascularization, intact palmar arch and presence of digital run-off. The presence of an incomplete arch and poor digital run-off were associated with a phalanx or digital amputation. ConclusionsUpper extremity interventions for critical ischemia are associated with a high rate of success. Major amputations are rare and the many can be treated nonoperatively. In appropriately selected patients, both endovascular and open interventions have a high rate of success.

Intravenous Drug Use Is Novel Predictor of Infectious Intracranial Aneurysms in Patients with Infective Endocarditis

Infectious intracranial aneurysms (IIAs) are a rare but potentially devastating complication of infective endocarditis. The clinical and radiographic findings that predispose patients to IIA remain poorly understood. We performed a retrospective review of a prospectively maintained database of consecutive endocarditis patients undergoing catheter-based angiography at a single tertiary-level academic center during the period of July 2013-December 2017. Patient records were reviewed for clinical and radiographic characteristics that may be associated with IIA. Multivariate regression models were used to evaluate the relationship between clinical and radiographic characteristics and presence of IIA on invasive imaging. Of 92 patients included in this analysis, 12 of them with 19 IIAs were discovered. Univariate analysis identified age, male sex, presence of hemorrhage, and history of IV drug use (IVDU) as predictors of IIA presence. After multivariate analysis, only intracranial hemorrhage and IVDU remained as independent predictors of IIA. Presence of hemorrhage on noninvasive imaging and history of IVDU are independently predictive of IIA presence in patients with infectious endocarditis. Risk stratification using these 2 factors may help identify the most vulnerable populations for IIA formation.

Clinical Outcomes of Endovascular Thrombectomy in Tissue Plasminogen Activator versus Non-Tissue Plasminogen Activator Patients at Primary Stroke Care Centers

Background:The effect of intravenous tissue plasminogen activator (IV tPA) administration before endovascular intervention as compared to without at thrombectomy-capable low-volume centers on procedural aspects and patient outcomes has not been investigated.Methods:Retrospective chart review was performed in all consecutive large vessel cerebrovascular accident patients treated with endovascular therapy at two select rural primary stroke centers between 2011 and 2015. Patients’ data regarding age, sex, and medical history, as well as thrombus location by catheter-based cerebral angiography, postprocedural reperfusion status, and clinical outcomes were reviewed. The primary outcome measure of the study was a comparison of modified Rankin scale (MRS) at 90 days in patients’ postendovascular thrombectomy with prior IV tPA administration versus those who underwent thrombectomy and did not qualify for preprocedural IV tPA.Results:After application of the set inclusion and exclusion criteria, data of 46 out of 65 patients were analyzed. Twenty-three patients (50%) received IV tPA before thrombectomy and 23 patients did not qualify for IV tPA (50%). Successful recanalization (thrombolysis in cerebral infarction 2b/3) was achieved in 86% (20/23 patients) of thrombectomy patients without preprocedural IV tPA and 82% (19/23) of patients who received it (odds ratio [OR]: 0.03, confidence interval [CI]: 95% 0.062–0.16, P < 0.0001). MRS of 2 or less at 90 days was 43.4% (10/23) in patients with no preprocedural IV tPA and 39.1% (9/23) in the combined therapy group (OR: 0.84, CI: 0.26–2.70, P = 0.8).Conclusion:Patients undergoing endovascular thrombectomy for large vessel occlusion at select low-volume rural centers showed benefit from this treatment regardless of IV tPA administration. Clinical outcomes and complications at select low-volume thrombectomy-proficient centers are comparable to large volume comprehensive stroke centers as well as the landmark studies proving the efficacy of endovascular treatment.

A New Technique for the Assessment of Cerebral Vasodilatory Capacity as Part of Catheter-Based Cerebral Angiography

Previous studies have demonstrated the value of cerebral vasodilatory capacity assessment for risk stratification in patients with extracranial arterial stenosis or occlusion. We describe a new method that assesses cerebral vasodilatory capacity as part of catheter-based cerebral angiography. We assessed regional cerebral blood volume (rCBV) in the arterial distribution of interest using a controlled contrast injection through a diagnostic catheter placed in the common carotid or the subclavian artery. rCBV maps were created using predefined algorithm based on contrast distribution in the venous phase (voxel size 0.466 mm3) into high, intermediate, low, and no detectable rCBV regions. rCBV maps were acquired again after the administration of intra-arterial nicardipine (1.5-2.5 mg), and percentage increases of the area of various grades of rCBV were calculated. Three patients with internal carotid artery stenosis (32% - 64% in severity) and 1 patient with extracranial vertebral artery stenosis (46% in severity) were assessed. There was a variable but consistent increase in the area of high rCBV in the ipsilateral hemisphere in 3 patients with internal carotid artery flow (5.5%-24.5%) and the cerebellum (9.6%) in 1 patient with vertebral artery flow assessments. The increase in high rCBV was most prominent in the patient who received 2.5 mg (24.5%) and least prominent in a patient who received 1.5 mg (5.5%) of intra-arterial nicardipine. There was a concurrent reduction in areas of intermediate and low rCBV (shift) in 3 patients, and there was an increase in all areas of rCBV grades (addition) in 1 patient. Selective assessment of cerebral vasodilatory response in the affected arterial distribution is feasible during catheter-based cerebral angiography.

Utility of cone-beam computed tomography angiography for the assessment of vertebral artery dissection

Vertebral artery dissection (VAD) has been recognized as a cause of headache and stroke. Accurate evaluation of dissection using several modalities such as catheter-based angiography, CT angiography (CTA), and magnetic resonance imaging (MRI) is essential for subsequent management. The aim of this retrospective study is to compare cone-beam computed tomography angiography (CBCT-A) with other image modalities for the evaluation of the detailed structures of VAD. Twenty-five consecutive cases identified as having VAD were included. They underwent catheter-based angiography (2D-digital subtraction angiography [DSA], 3D-DSA, and CBCT-A), CTA, and MRI for the diagnosis of VAD. CBCT-A was performed following conventional angiography. Dissecting lesions were evaluated for the presence of intimal flap/double lumen, wall thickening, and enhancement of outer wall. This study results showed that CBCT-A was the most superior modality to detect intimal flap/double lumen (found in 56% of the cases) due to its high spatial resolution. MRI was superior for the assessment of wall thickening as an intramural hematoma in 76% of the cases. However, wall thickening was detected in 44% of cases using CBCT-A. In 5 cases, enhancement of outer wall was identified only in CBCT-A. In conclusion, CBCT-A provides detailed luminal and wall morphology of VADs. CBCT-A is useful for the accurate diagnosis of VADs.

Abstract WP268: Evaluation and Validation of Prehospital Acute Stroke Severity Scale to Predict Large Vessel Occlusion in Patients with Proven Large Vessel Occlusion; Single Center Study in US

Background: In 2015 guidelines regarding endovascular treatment (ET) of Large Vessel Occlusion (LVO) in acute ischemic stroke (AIS) were changed, leading to more patients being transferred to comprehensive stroke centers (CSC) for ET in selected patients, sometimes bypassing primary stroke centers. In the era of ET, there is a need for a simple yet sensitive pre-hospital tool to triage appropriate patients to CSCs. Many prehospital stroke scales predicting LVO are not in widespread clinical use because they are complex and not reliable. A recently published Denmark study demonstrated the PASS tool (Score range 0-3) for detecting LVO where a score of ≥2 was considered to be optimal in predicting LVO with sensitivity of 0.66. Methods: A retrospective analysis of AIS patients with confirmed anterior circulation LVO by catheter-based cerebral angiography between January 2015 and June 2016 was conducted. PASS scores were calculated and correlated with NIHSS to assess for severity of the stroke. Results: Fifty-four patients received ET during the study period. Those who had posterior circulation LVO were excluded, leaving 44 patients for final analysis. Only 5 (11.4%) patients had PASS score of &lt;2 while 39 patients (88.6 %) had a score of ≥2 showing sensitivity of 0.89 for those patients with LVO. Average NIHSS scores were 11 (95% CI 6.6-15) for PASS &lt;2 and 20 (95% CI 18.5-22.5) for PASS ≥2 (p value 0.005). Conclusion: The PASS tool is simple, quick, and easy to perform and has high sensitivity in AIS patients with LVO. To assess its value and efficacy in real time it should be implemented into EMS systems and be performed in the pre-hospital setting.

Contemporary management of isolated chronic infrarenal abdominal aortic dissections

The purpose of this study was to report the presentation, treatment, and follow-up of isolated infrarenal aortic dissections. A review of 37 patients with isolated infrarenal aortic dissections was performed. Computed tomography scans with intravenous administration of contrast material were examined for all patients; catheter-based angiography, magnetic resonance angiography, and duplex ultrasound were used selectively. In dissections associated with the development of abdominal aortic aneurysm (AAA), the aneurysm growth rate was determined by measuring the change in maximum aneurysm diameter over time and dividing that by the duration of observation. The majority of infrarenal abdominal aortic dissection patients were male (67.6%). Hypertension (77.1%) and hyperlipidemia (77.1%) were the most common comorbidities among these patients. Aortic atherosclerosis was present in the majority of patients (60.0%); 67.6% of dissections were discovered incidentally and were asymptomatic. The mean dissection length was 5.84± 4.23cm. Concomitant AAAs were present in 48.6% of cases with an average maximum diameter of 4.38± 1.41cm. The aneurysm growth rate was 1.2mm/y. Aneurysms were significantly larger in men than in women (4.87± 1.31 vs 3.12± 0.67cm; P= .001). Endovascular intervention was performed on 14 (37.8%) patients, open surgery was performed on 1 (2.7%) patient, and surveillance with conservative medical treatment was used for 22 (59.5%) patients. Ten patients were treated successfully with endovascular repair for progressive aneurysm expansion. At the time of intervention, the mean AAA diameter was 5.04± 1.39cm. The mean growth rate for aneurysms that were intervened on was 2.3mm/y. The mean diameter of AAAs that were not intervened on was 3.56± 1.04cm. Type II endoleaks were observed in three (30%) patients who underwent endovascular repair. None of these were associated with aneurysm growth and none required reintervention. The mortality rate for endovascular intervention was 0%. The only open surgical repair performed was on a patient with a ruptured AAA, which the patient did not survive. Angioplasty with stent or stent graft placement was performed in four patients for the treatment of symptomatic arterial insufficiency resulting from aortic dissection. No patients experienced restenosis, and no reinterventions were performed. Isolated infrarenal aortic dissection is an uncommon vascular disease that is related to hypertension, hyperlipidemia, and atherosclerosis and may be associated with infrarenal AAA formation. The presence of dissection does not appear to increase the risk of complication or mortality for repair of concomitant aneurysm or for treatment of stenosis.

Diagnostic Evaluation of Chronic Thromboembolic Pulmonary Hypertension.

Pulmonary hypertension is defined by a mean pulmonary artery pressure greater than 25 mm Hg. Chronic thromboembolic pulmonary hypertension (CTEPH) is defined as pulmonary hypertension in the presence of an organized thrombus within the pulmonary vascular bed that persists at least 3 months after the onset of anticoagulant therapy. Because CTEPH is potentially curable by surgical endarterectomy, correct identification of patients with this form of pulmonary hypertension and an accurate assessment of surgical candidacy are essential to provide optimal care. Patients most commonly present with symptoms of exertional dyspnea and otherwise unexplained decline in exercise capacity. Atypical chest pain, a nonproductive cough, and episodic hemoptysis are observed less frequently. With more advanced disease, patients often develop symptoms suggestive of right ventricular compromise. Physical examination findings are minimal early in the course of this disease, but as pulmonary hypertension progresses, may include nonspecific finding of right ventricular failure, such as a tricuspid regurgitation murmur, pedal edema, and jugular venous distention. Chest radiographs may suggest pulmonary hypertension, but are neither sensitive nor specific for the diagnosis. Radioisotopic ventilation-perfusion scanning is sensitive for detecting CTEPH, making it a valuable screening study. Conventional catheter-based pulmonary angiography retains an important role in establishing the presence and extent of chronic thromboembolic disease. However, computed tomographic and magnetic resonance imaging are playing a growing diagnostic role. Innovative technologies such as dual-energy computed tomography, dynamic contrast-enhanced magnetic resonance imaging, and optical coherence tomography show promise for contributing diagnostic information and assisting in the preoperative characterization of patients with CTEPH.

Finding the Nidus: Detection and Workup of Non-Central Nervous System Arteriovenous Malformations.

Vascular anomalies are a diverse group of pathologic conditions. They have different manifestations, natural histories, and treatments. Compared with other vascular malformations, arteriovenous malformations (AVMs) are considered the most symptomatic and difficult to manage. AVMs inherently progress and have a high rate of recurrence after treatment. Imaging helps provide an accurate and early diagnosis, which can then be used to direct appropriate management, with embolization evolving as the primary therapy. Thus, radiology plays a crucial role in the detection, workup, and management of AVMs. Ultrasonography (US) is a useful initial imaging modality, particularly when AVMs involve the extremities or a superficial or accessible location. Limitations include poor identification of soft-tissue and bone components, as well as suboptimal evaluation of deep or complex AVMs. Magnetic resonance (MR) angiography is the preferred imaging modality for AVMs and should be considered in any symptomatic patient or in the initial evaluation of vascular anomalies that are equivocal at US. Computed tomographic angiography should be reserved for those patients who are unable to undergo MR angiography or for evaluation of acute symptoms, such as bleeding or airway compromise. Conventional catheter-based angiography is useful for real-time depiction and evaluation of AVMs, particularly in the planning and execution of endovascular treatment and in the diagnosis of an AVM when findings from noninvasive imaging are equivocal for a high-flow component. As with the diagnostic workup, MR angiography is the preferred posttreatment modality. (©)RSNA, 2016.

Modern diagnostics for type B aortic dissection

BackgroundUndifferentiated chest pain is one of the most common complaints in the acute care setting. Type B aortic dissection is an important cause of chest pain and a complex clinical entity, which carries significant morbidity and mortality and requires accurate clinical and radiological evaluation.MethodsImaging technologies have become an irreplaceable tool to establish the diagnosis of aortic dissection and to plan treatment strategies. Computed tomography is an important component in this process, replacing catheter-based angiography as the most commonly used preoperative and postoperative imaging modality for the thoracic aorta. The use of functional imaging methods, such as magnetic resonance imaging and echocardiography is evolving. These methods are able to provide the clinically relevant anatomical, hemodynamic and biomechanical information that is necessary for accurate diagnosis, risk stratification and patient selection for treatment.ConclusionAdvanced image acquisition equipment and expertise are increasingly available in a growing number of institutions and as a consequence, existing strategies for the management of type B dissection are rapidly evolving.