Current Evidence for Endovascular Therapies in the Management of Acute Deep Vein Thrombosis.

Acute lower extremity deep vein thrombosis (DVT), specifically proximal iliofemoral DVT, is a relatively common disorder that can result in a chronic debilitating post-thrombotic syndrome (PTS), with a significant effect on a patient's quality of life. Anticoagulation is first-line therapy; however, percutaneous interventions have emerged as treatment options for patients where there is concern that anticoagulation alone will not resolve the DVT as well as prevent PTS. This paper will discuss the existing data on these interventions and review current endovascular techniques, including catheter-directed thrombolysis, pharmacomechanical thrombectomy, and large-bore mechanical thrombectomy in the management of DVT.

Added Value of Cone-Beam CT to Identify Arterial Supply during Genicular Artery Embolization for Knee Osteoarthritis.

PURPOSE: To evaluate if the addition of cone-beam computed tomography (CT) to digital subtraction angiography (DSA) improves the identification of the genicular arteries during genicular artery embolization (GAE) for knee pain secondary to osteoarthritis (OA). MATERIALS AND METHODS: This single-center study retrospectively analyzed 222 patients who underwent GAE for painful knee OA between May 2018 and April 2022. Intraprocedural cone-beam CT and DSA images were reviewed independently by 2 sets of interventional radiologists. DSA was performed for all patients. Technically adequate cone-beam CT was available for 205 patients (92.3%). The presence of the genicular arteries identified by cone-beam CT and DSA was compared using Φ coefficients. Embolization targets identified by both cone-beam CT and DSA were evaluated against those identified by DSA alone. RESULTS: Genicular arteries with the highest concordance between cone-beam CT and DSA were the inferior lateral (196 vs 198; Φ = 0.3530; P < .0001), superior lateral (197 vs 200; Φ = 0.3060; P < .0001), and superior medial genicular (186 vs 161; Φ = 0.2836; P < .0001) arteries. Cone-beam CT demonstrated higher rates of detection of the inferior medial (195 vs 178; Φ = 0.04573; P = .5150) and median genicular arteries (200 vs 192; Φ = 0.04573; P = .5150). Meanwhile, genicular arteries less frequently identified by cone-beam CT were the descending genicular (197 vs 200; Φ = -0.03186; P = .6502), superior patellar (175 vs 184; Φ = 0.1332; P = .0569), and recurrent anterior tibial (156 vs 186; Φ = 0.01809; P = .7969) arteries. Cone-beam CT in combination with DSA identified 13.4% (372 vs 328) more targets compared to DSA alone. CONCLUSIONS: Based on the results of the current study, cone-beam CT serves as a valuable adjunct for visualizing the genicular arteries during GAE, and together with DSA, it identifies more potential embolization targets.

Procedural outcomes associated with use of the AngioVac System for right heart thrombi: A safety report from RAPID registry data.

Background: Right heart thrombi can be a source of considerable morbidity and mortality, especially when associated with pulmonary embolism. Methods: To understand the safety and procedural efficacy associated with vacuum-assisted thrombectomy using the AngioVac System (AngioDynamics, Latham, NY, USA) to remove right heart thrombi, we conducted a subanalysis of the Registry of AngioVac Procedures in Detail (RAPID) multicenter registry representing 47 (20.1%) of 234 participants in the registry. Forty-two (89.4%) patients had thrombi located in the right atrium alone, three (6.4%) in the right ventricle alone, and two (4.3%) in both the right atrium and ventricle. Four (8.5%) patients had concomitant caval thrombi, three (6.4%) also had catheter-related thrombi, and one (2.1%) patient had both caval and catheter-related thrombi with their right heart thrombi. Results: Extracorporeal bypass time was less than 1 hour for 39 (83.0%) procedures. Seventy to 100% removal of thrombus was achieved in 59.6% of patients. Estimated blood loss was less than 250 cc for 43 procedures (91.6%). Mean hemoglobin decreased from 10.7 ± 2.2 g/dL preoperatively to 9.6 ± 1.6 g/dL postoperatively. Transfusions were administered for eight procedures (17.0%), with only one (2.1%) patient receiving more than 2 units of blood. Six patients (12.8%) experienced procedure-related adverse events, including three (6.4%) patients who experienced distal emboli and three (6.4%) patients who developed bleeding-related complications. All adverse events resolved prior to discharge. There was one death (2.1%) reported that was not procedure related. Conclusion: Vacuum-assisted thrombectomy can be performed safely in patients with right heart thrombi. ClinicalTrials.gov Identifier: NCT04414332.

Minimizing table time in patients with claustrophobia using focused ferumoxytol-enhanced MR angiography (f-FEMRA): a feasibility study.

OBJECTIVES: To assess the feasibility of a rapid, focused ferumoxytol-enhanced MR angiography (f-FEMRA) protocol in patients with claustrophobia. METHODS: In this retrospective study, 13 patients with claustrophobia expressed reluctance to undergo conventional MR angiography, but agreed to a trial of up to 10 min in the scanner bore and underwent f-FEMRA. Thirteen matched control patients who underwent gadolinium-enhanced MR angiography (GEMRA) were identified for comparison of diagnostic image quality. For f-FEMRA, the time from localizer image acquisition to completion of the angiographic acquisition was measured. Two radiologists independently scored images on both f-FEMRA and GEMRA for arterial and venous image quality, motion artefact and diagnostic confidence using a 5-point scale, five being best. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in the aorta and IVC were measured. The Wilcoxon rank-sum test, one-way ANOVA with Tukey correction and two-tailed t tests were utilized for statistical analyses. RESULTS: All scans were diagnostic and assessed with high confidence (scores ≥ 4). Average scan time for f-FEMRA was 6.27 min (range 3.56 to 10.12 min), with no significant difference between f-FEMRA and GEMRA in diagnostic confidence (4.86 ± 0.24 vs 4.69 ± 0.25, p = 0.13), arterial image quality (4.62 ± 0.57 vs 4.65 ± 0.49, p = 0.78) and motion artefact score (4.58 ± 0.49 vs 4.58 ± 0.28, p > 0.99). f-FEMRA scored significantly better for venous image quality than GEMRA (4.62 ± 0.42 vs 4.19 ± 0.56, p = 0.04). CNR in the IVC was significantly higher for steady-state f-FEMRA than GEMRA regardless of the enhancement phase (p < 0.05). CONCLUSIONS: Comprehensive vascular MR imaging of the thorax, abdomen and pelvis can be completed in as little as 5 min within the magnet bore using f-FEMRA, facilitating acceptance by patients with claustrophobia and streamlining workflow. ADVANCES IN KNOWLEDGE: A focused approach to vascular imaging with ferumoxytol can be performed in patients with claustrophobia, limiting time in the magnet bore to 10 min or less, while acquiring fully diagnostic images of the thorax, abdomen and pelvis.

Preservation of Posterior Tibial Artery Flow Following Dissection With Associated Aneurysmal Degeneration in Ehlers-Danlos Syndrome Type IV Treated With Flow-Diverting Stent.

Ehlers-Danlos syndrome type IV (EDS-IV), the vascular type, is a rare genetic disorder affects the large and medium size arteries resulting in dissections, often with aneurysmal degeneration, intramural hematomas and pseudoaneurysms. Embolization or ligation is standard management for aneurysm formation. We present a case of an EDS-IV patient with a posterior tibial artery dissection with associated aneurysm successfully treated with Flow Diversion stent (FDS) preserving vessel patency and excluding the aneurysm. FDS technology allows for low profile, micro-catheter deliverable treatment options to exclude aneurysms in EDS-IV patients that are may be prone to spasm and dissection using more conventional stent graft technology.

Collaboration is Key - Bridging the Gap and Building an IR Endoscopy Practice.

While the tools and techniques employed by interventional radiologists on a day-to-day basis translate well to learning the skills required to perform basic endoscopic interventions, collaboration with other specialties is crucial to the success of an interventional radiology endoscopy program. As in any field in medicine, the paramount goal is to improve patient care. Adding the ability to directly visualize structures through an endoscope to certain interventional radiologic procedures may greatly augment the efficacy, safety, and success of interventional radiology procedures. Colleagues in urology, gastroenterology, and surgery should be involved in decision-making and treatment planning to ensure that a shared vision for optimal patient care is achieved.

Prostate Artery Embolization for Giant Prostatic Enlargement: Short-Term Efficacy and Safety.

Eight patients with giant prostatic enlargement > 200 mL and lower urinary tract symptoms who underwent bilateral prostatic artery embolization (PAE) were reviewed. Mean prostate volume decreased from 318.2 mL to 212.2 mL (P < .01). At 5-month mean follow-up, International Prostate Symptom Score decreased by 16.7 points (P < .05), and urinary quality of life improved by 3.0 points (P < .01). Three of 4 catheter-dependent patients no longer needed catheterization after the procedure. No major complications were encountered. Preliminary results suggest PAE is safe and effective in patients with giant prostatic enlargement > 200 mL.

Interventional radiology-operated percutaneous cholecystoscopy with ultrasonic lithotripsy and stone basket retrieval: A treatment for symptomatic cholelithiasis in non-operative candidates.

Interventional radiology-operated percutaneous endoscopy has seen a recent resurgence with potential to return to the scope of Interventional Radiology practice. Endoscopy adds a new dimension to the Interventional Radiology armamentarium by offering a unique opportunity to diagnose and treat conditions under direct visualization with improved maneuverability. Cholecystoscopy (gallbladder endoscopy), as a method for percutaneous removal of gallstones, is an effective treatment option in patients with symptomatic cholelithiasis who are poor candidates for surgical cholecystectomy. This article presents a case of Interventional Radiology-operated cholecystoscopy using ultrasonic lithotripsy and stone basket retrieval with an emphasis on the equipment, technique, and peri-procedural management essential to the procedure, as well as a review of the literature.

Recanalization of prostatic artery chronic total occlusion prior to prostatic artery embolization.

Urinary obstruction secondary to benign prostatic hyperplasia is a late manifestation of the disease, and a poor prognostic sign for responding to conservative therapies. Prostatic artery embolization - when performed successfully - can be an effective treatment for reducing obstructive urinary symptoms. Outlined in this report is the successful recanalization of a prostatic artery chronic total occlusion prior to embolization in an 89-year-old man with benign prostatic hyperplasia, who initially presented with urinary obstruction. Prostatic artery recanalization was possible using a specialized crossing technique from peripheral arterial disease interventions, and allowed for more distal embolization of the prostate gland. This technique may be useful when advanced atherosclerotic disease limits the feasibility and clinical success of prostatic artery embolization.

Intervention in Massive Pulmonary Embolus: Catheter Thrombectomy/Thromboaspiration versus Systemic Lysis versus Surgical Thrombectomy.

Massive pulmonary embolus (PE), defined as hemodynamic shock from acute PE, is a life-threatening condition. Deaths from massive PE, especially when unsuspected, occur within minutes to hours of onset and as such prompt intervention can be lifesaving. Acute massive PE patients have traditionally been candidates for treatment with intravenous systemic thrombolysis to improve pulmonary artery pressure, arteriovenous oxygenation, and pulmonary perfusion in an effort to reduce mortality. However, patients with contraindications to systemic thrombolysis or those who have failed thrombolysis may benefit from other techniques including endovascular and surgical embolectomy. This article will review the current medical management as well as catheter-directed therapies and surgical embolectomy in the treatment of patients with massive PE.

Ferumoxytol-enhanced MR Angiography for Vascular Access Mapping before Transcatheter Aortic Valve Replacement in Patients with Renal Impairment: A Step Toward Patient-specific Care.

Purpose To assess the technical feasibility of the use of ferumoxytol-enhanced (FE) magnetic resonance (MR) angiography for vascular mapping before transcatheter aortic valve replacement in patients with renal impairment. Materials and Methods This was an institutional review board-approved and HIPAA-compliant study. FE MR angiography was performed at 3.0 T or 1.5 T. Unenhanced computed tomographic (CT) images were used to overlay vascular calcification on FE MR angiographic images as composite fused three-dimensional data. Image quality of the subclavian and aortoiliofemoral arterial tree and confidence in the assessment of calcification were evaluated by using a four-point scale (4 = excellent vascular definition or strong confidence). Signal intensity nonuniformity as reflected by the heterogeneity index (ratio between the mean standard deviation of luminal signal intensity and the mean luminal signal intensity), signal-to-noise ratio, and consistency of luminal diameter measurements were quantified. Findings at FE MR angiography were compared with pelvic angiograms. Results Twenty-six patients underwent FE MR angiography without adverse events. A total of 286 named vascular segments were scored. The image quality score was 4 for 99% (283 of 286) of the segments (κ = 0.9). There was moderate to strong confidence in the ability to assess vascular calcific morphology in all studies with complementary unenhanced CT. The steady-state luminal heterogeneity index was low, and signal-to-noise ratio was high. Interobserver luminal measurements were reliable (intraclass correlation coefficient, 0.98; 95% confidence interval: 0.98, 0.99). FE MR angiographic findings were consistent with correlative pelvic angiograms in all 16 patients for whom the latter were available. Conclusion In patients with renal impairment undergoing transcatheter aortic valve replacement, FE MR angiography is technically feasible and offers reliable vascular mapping without exposure to iodine- or gadolinium-based contrast agents. Thus, the total cumulative dose of iodine-based contrast material is minimized and the risk of acute nephropathy is reduced. © RSNA, 2017 Online supplemental material is available for this article.

Chronic portomesenteic venous thrombosis complicated by a high flow arteriovenous malformation presenting with gastrointestinal bleeding.

Portomesenteric venous thrombosis is a rare but potentially life-threatening condition. The presenting symptoms of chronic portomesenteric venous thrombosis are often non-specific but may present with variceal bleeding. We present the first reported case of chronic portomesenteric venous thrombosis causing a high flow arteriovenous malformation that resulted in extensive gastrointestinal bleeding.

Computed tomography angiography of lower extremities in the emergency room for evaluation of patients with gunshot wounds.

OBJECTIVE: To assess the role of CT angiography in the evaluation of patients with lower extremity gunshot wounds in the emergency room. MATERIALS AND METHODS: Eighty patients (73 male, 7 female, mean age 26 years) underwent CT angiography for the evaluation of lower extremity gunshot injuries. Imaging was conducted on the basis of standardized protocols utilizing 16-slice and 64-slice multidetector systems and images were qualitatively graded and assessed for various forms of arterial injury. RESULTS: CT angiography findings indicative of arterial injury were observed in 24 patients (30%) and a total of 43 arterial injuries were noted; the most common form was focal narrowing/spasm (n = 16, 37.2%); the most common artery involved was the superficial femoral artery (n = 12, 50%). In qualitative assessment of images based on a 4-point grading system, both readers considered CT angiography diagnostically excellent (grade 4) in most cases. Surgical findings were consistent with CT angiography and follow-up of patients' medical records showed no arterial injuries in patients with normal findings on initial imaging. CONCLUSION: Our findings demonstrate that CT angiography is an effective imaging modality for evaluation of lower extremity gunshot wounds and could help limit more invasive procedures such as catheter angiography to a select group of patients. KEY POINTS: • CT angiography efficiently evaluates lower extremity gunshot wounds. • CT angiography provides image quality sufficiently reliable for assessment of gunshot injuries. • CT angiography could help limit invasive procedures to select patients.

Safety of hydroinfusion in percutaneous thermal ablation of hepatic malignancies.

PURPOSE: Hydroinfusion is a commonly used ancillary procedure during percutaneous thermal ablation of the liver that is used to separate and protect sensitive structures from the ablation zone. However, risks of hydroinfusion have not been systematically studied. The purpose of the present study was to systematically examine the frequency and severity of local and systemic complications related to hydroinfusion. MATERIALS AND METHODS: From January 2009 to April 2012, 410 consecutive patients underwent percutaneous thermal hepatic tumor ablation. One hundred fifty patients in the study group underwent hydroinfusion and 260 in the control group did not. Patient charts and imaging studies of both groups were reviewed to compare incidences of complications that could potentially be caused by hydroinfusion, including pleural effusion, bowel injury, infection, electrolyte imbalance, and hyperglycemia. RESULTS: Pleural effusions were found to occur more commonly in the hydroinfusion group (45.3%) than in the control group (16.5%). Pleural effusions were significantly larger (P < .001) and more likely to be symptomatic (six of 150 patients; P = .006) in the hydroinfusion group than in the control group (one of 260 patients). Multiple patient and tumor characteristics were analyzed for association with development of major hydroinfusion-type complications (requiring therapy or extended/repeat hospitalization). Subcapsular location of tumor was the only variable to reach statistical significance (P = .009), with all major hydroinfusion-type complications (n = 10) occurring in patients with subcapsular tumors. CONCLUSIONS: Hydroinfusion is a safe procedure overall. However, pleural effusions occur commonly after hydroinfusion, tend to be moderate or large in size, and are occasionally symptomatic.

Current treatment of renal artery aneurysms may be too aggressive.

OBJECTIVE: Most studies recommend repair of renal artery aneurysms (RAAs) >2 cm in diameter in asymptomatic patients, but other studies have suggested that their natural history may be more benign. We hypothesized that rupture and death in patients with asymptomatic RAAs is low and that current recommendations for RAA treatment at 2 cm may be too aggressive. METHODS: Retrospective review of all RAAs treated at a tertiary care medical center from 2002 to 2012. RESULTS: Fifty-nine RAA were identified in 40 patients (mean age at diagnosis, 56 years; male:female ratio, 17:23); 31 were saccular, 8 were fusiform, and 5 were bilobed. Twenty-nine patients were asymptomatic; the remainder of patients presented with hematuria (n = 4), abdominal pain (n = 3), difficult-to-control hypertension (n = 3), or flank pain (n = 2). Aneurysm location included the main renal artery bifurcation (n = 35), main trunk (n = 7), primary branch (n = 6), pole artery (n = 6), and secondary branch (n = 1). Operative management of RAAs included vein patch (n = 6), prosthetic patch (n = 4), primary repair (n = 3), plication (n = 1), patch and implantation (n = 1), and ex vivo repair (n = 1). Eight asymptomatic RAAs were treated surgically (mean RAA diameter = 2.4 ± 0.1 cm, range, 2-3 cm), with the remaining 33 asymptomatic RAAs being managed conservatively (mean RAA diameter = 1.4 ± 0.1 cm, range, 0.6-2.6 cm). Mean hospital length of stay was 4 days, with no late postoperative complications and 0% mortality. Non-operated patients were followed for a mean of 36 ± 9 months, with no late acute complications and 0% mortality. Mean RAA growth rate of patients with multiple imaging studies was 0.60 ± 0.16 mm/y. CONCLUSIONS: The rate of aneurysm rupture and death in our untreated RAA patients is zero, the growth rate is 0.60 ± 0.16 mm/y, and there were no adverse outcomes in asymptomatic RAAs >2 cm that were observed. We may currently be too aggressive in treating asymptomatic RAAs.