Distal Radial Artery Access for Noncoronary Endovascular Treatment Is a Safe and Feasible Technique

PurposeTo evaluate safety and feasibility of distal radial artery (DRA) access for noncoronary interventional radiology procedures.Materials and MethodsAll interventional radiology procedures by means of DRA puncture from July 2017 to August 2018 were retrospectively reviewed. Eighty-two punctures in 56 patients were included, mostly in male patients (84% vs 16%). Mean age was 67.8 years (range, 33.3–87.3 years); mean height was 172 cm (range, 142–190 cm); and mean weight was 83 kg (range, 43–120 kg). Procedural characteristics, technical success, and complication rates were gathered from the medical records and follow-up ultrasound when available. Prerequisites for DRA access were adequate radioulnar collateral circulation, sufficient radial artery diameter, and informed consent in patients initially intended for conventional transradial access.ResultsProcedures included transarterial chemoembolization (n = 34), yittrium-90 pretreatment angiography (n = 21), yittrium-90 administration (transarterial radioembolization; n = 20), and embolization of visceral organs (n = 7). Both 4-Fr (n = 35) and 5-Fr (n = 46) sheaths were used. Technical success of DRA access was 97.6%, with conversion to transfemoral access in 2 cases (2.4%). No major complications were reported as a result of DRA access.ConclusionDRA access is a feasible and safe technique for abdominal interventional radiology embolization procedures. No radial artery occlusion or other major complications were observed in patients who underwent follow-up ultrasound.     

Hand Sensibility after Transradial Arterial Access: An Observational Study in Patients with and without Radial Artery Occlusion

PurposeTo evaluate hand sensibility after transradial access (TRA) in patients with and without radial artery occlusion (RAO).Materials and MethodsIn this study, 71 patients with and without RAO after TRA for a coronary intervention were studied (79% male, mean age 65 y ± 9). Sensibility testing of both hands was performed with the Semmes-Weinstein monofilaments test. The primary endpoint was abnormal sensibility, defined as diminished sensibility in at least 1 radial nerve–supplied dermatome. The contralateral hand served as control. The influence of TRA, RAO, and clinical characteristics on hand sensibility was evaluated.ResultsIn patients with RAO, more abnormal sensibility was observed on the RAO side compared with the control hand (72% vs 17%, P < .01). In patients without RAO, more abnormal sensibility was observed in the TRA hand compared with the control hand (43% vs 10%, P < .01). When analyzing all hands separately, TRA, RAO, and diabetes were independent predictors for abnormal hand sensibility in a multivariate model (odds ratio 3.8, 95% confidence interval 1.4–9.8, P < .01; odds ratio 3.0, 95% confidence interval 1.1–8.5, P = .03; odds ratio 3.5, 95% confidence interval 1.4–8.6, P < .01).ConclusionsTRA and RAO are associated with diminished hand sensibility.     

Transradial versus Transfemoral Access for Patients with Liver Cancer Undergoing Hepatic Arterial Infusion Chemotherapy: Patient Experience and Procedural Complications

PurposeTo determine whether transradial access (TRA) is a more favorable and safe method for hepatic arterial infusion chemotherapy (HAIC) than transfemoral access (TFA).Materials and MethodsRetrospective and prospective cohorts of patients with liver cancer were included. Sixty-seven patients in the retrospective cohort were divided into 2 groups: (a) TRA-HAIC (n = 24) and (b) TFA-HAIC (n = 43). Another 33 patients were prospectively enrolled to receive both TRA and TFA for HAIC in a crossover design. Prolonged arterial access was required for up to 48 hours. The primary endpoint was quality of life (QOL) using the visual analog scale. The secondary endpoints mainly included procedural success, adverse events, and operation time.ResultsPatient QOL measures revealed significantly lower scores of indices in the TRA-HAIC group than in the TFA-HAIC group in the retrospective cohort (all P < .001). The significant improvement of the QOL indices by TRA-HAIC, such as overall discomfort (P = .019) and pain at the access site (P = .018), was validated in the prospective cohort. The satisfaction scores were significantly higher in the TRA-HAIC group than in the TFA-HAIC group, and patients preferred TRA-HAIC (P < .001). Radial artery occlusion (RAO) as an access-related adverse event occurred more frequently in both the retrospective and prospective cohorts (38% and 33%, P < .001 and P = .001, respectively). Notably, the multivariate analysis of RAO-associated factors showed that enoxaparin use was significantly correlated with a reduced risk of postprocedural RAO (P = .036).ConclusionsTRA was superior to TFA in patient experience. However, because of the high incidence of access-related adverse events, especially for RAO with a total incidence of 35%, strategies should be optimized for patients to benefit from TRA in future procedures.     

Outcome and Distal Access Patency in Subintimal Arterial Flossing with Antegrade-Retrograde Intervention for Chronic Total Occlusions in Lower Extremity Critical Limb Ischemia

PurposeTo report the outcome and distal access patency of the Subintimal Arterial Flossing with Antegrade-Retrograde Intervention (SAFARI) technique for chronic total occlusion (CTO) in critical limb ischemia (CLI).Materials and MethodsFrom January 2009 to June 2015, 220 SAFARI procedures were performed for 200 limbs in 191 patients (108 males [56.5%]; median age, 70 years old; range, 36 to 97 years old) with CLI (9.4% were Fontaine classification 3; and 90.6% were Fontaine classification 4). Distal access was obtained from the distal superficial femoral artery (n = 6), popliteal artery (n = 49), anterior tibial artery (n = 56), dorsalis pedis (n = 51), peroneal artery (n = 12), posterior tibial artery (n = 45), and lateral plantar artery (n = 1). Distal access hemostasis was obtained with internal balloon tamponade in 71.4% (n = 157). Outcome measurements were technical success, freedom from major amputation and complications. Preprocedural angiograms of clinically driven repeat interventions were reviewed in 73 cases for distal access patency.ResultsTechnical success was achieved in 80.5% (n = 177). Reasons for technical failure include inability to obtain distal access (n = 3), cross the occlusion retrogradely (n = 16), re-enter the true lumen (n = 9), and achieve antegrade blood flow after the procedure (n = 15). Freedom from major amputation for technically successful procedures was 84.7%, 82.9%, and 81.9% at 6, 12, and 24 months, respectively. There were 3 cases of distal access bleeding with 1case that required coil embolization. The distal access remained patent in 80.8% of observable cases with repeated endovascular intervention.ConclusionsDistal retrograde arterial access (SAFARI) technique is safe and effective in the treatment of CTOs in the context of CLI, after failure of antegrade revascularization.     

Diagnosis and Treatment of Nonmaturing Fistulae for Hemodialysis Access via Transradial Approach: A Case-Control Study

PurposeTo compare outcomes of transradial access for endovascular treatment of nonmaturing hemodialysis fistulae compared to brachial arteriography followed by unidirectional or bidirectional fistula access for intervention.Materials and MethodsIn this institutional review board-approved, retrospective, case-control study, 56 consecutive patients with nonmaturing arteriovenous fistulae underwent percutaneous intervention between 2015 and 2018. The transradial group (n = 28) underwent radial artery access for diagnostic fistulography and intervention. The control group (n = 28) underwent retrograde brachial artery access for fistulography followed by unidirectional/bidirectional fistula access for intervention. Both groups had similar demographics, fistula characteristics, and stenosis locations.ResultsFewer punctures were required in the transradial group compared to controls (1.2 vs 2.4, P < .0001), and procedure time was shorter (64.9 vs 91.3 minutes, P = .0016). Anatomic, technical, and clinical success rates trended higher in the transradial group compared to controls (93% vs 86%, 96% vs 89%, and 82% vs 64%, respectively). Nonmaturation resulting in fistula abandonment was lower in the transradial group (3.7% vs 25%, P = .025). Primary unassisted patency at 3, 6, and 12 months was 77.1% ± 8.2%, 73.1% ± 8.7%, and 53.3% ± 10.6% in the transradial group, respectively, and 63.0% ± 9.3%, 55.6% ± 9.6%, and 48.1% ± 9.6% in the control group, respectively (P = .76). Primary assisted patency at 12 months was 92.3% ± 5.3% in the transradial group compared to 61.8% ± 9.6% at 12 months in the control group (P = .021). No major complications occurred. Minor complications were lower in the transradial group than in the control group (14% vs 39%, P = .068).ConclusionsTreatment of nonmaturing fistulae via a transradial approach was safe, improved midterm patency, and was associated with lower rates of fistula abandonment.     

Outcomes of Preventive Embolization of the Inferior Mesenteric Artery during Endovascular Abdominal Aortic Aneurysm Repair

PurposeTo evaluate the impact of preemptive inferior mesenteric artery (IMA) embolization on outcomes of endovascular abdominal aortic aneurysm (AAA) repair (EVAR).Materials and MethodsFrom January 2015 to July 2017, all patients undergoing elective EVAR or fenestrated EVAR (F-EVAR) for asymptomatic AAA in a single tertiary hospital were retrospectively included. Three groups of patients were defined: patients with a patent IMA who underwent embolization during EVAR/F-EVAR (group 1), those with a patent IMA who did not undergo embolization during EVAR/F-EVAR (group 2), and those with a chronically occluded IMA (group 3). Preoperative aortic morphology, demographics, and procedural details were recorded. Aneurysmal growth (≥5 mm), reintervention, and overall mortality rates were analyzed using multivariate proportional hazard multivariate modeling. Propensity scores were constructed, and inverse probability weighting was applied to a new set of multivariate analyses to perform a sensitivity analysis.ResultsA total of 266 patients (male, 95% [n = 249]) with a median age of 70 (65–77) years were included, with F-EVAR procedures comprising 87 (32.7%) of the interventions. There were 52, 142, and 72 patients in groups 1, 2, and 3, respectively. Changes in aneurysmal sac size did not differ between groups, nor did overall survival or reintervention rates at 24 months. IMA embolization was not identified as an independently protective factor for aneurysmal growth during follow-up (relative risk [RR] = 2.82/mm [0.96–8.28], P = .060), whereas accessory renal arteries (RR = 5.07/mm [1.72–14.96], P = .003) and a larger preoperative aneurysmal diameter (RR = 1.09/mm [1.03–1.15], P = .004) were independent risk factors for sac enlargement.ConclusionsPreventive embolization of the IMA during EVAR or F-EVAR did not promote aneurysmal sac shrinking or decrease the reintervention rate at 2-year follow-up.     

Inline Balloon Occlusion–Assisted Delivery of Ethylene Vinyl Alcohol Copolymer for Peripheral Arterial Applications: A Multicenter Case Series

PurposeTo assess the feasibility, safety, and efficacy of balloon-assisted delivery of ethylene vinyl alcohol copolymer (EVOH) for a range of peripheral arterial applications.Materials and MethodsSix academic medical centers entered retrospective data on 46 consecutive patients (27 men, 19 women; ages, 11–94 y; mean age, 50.3 y) who underwent 60 balloon-assisted EVOH procedures. The cohort was restricted to procedures involving peripheral, nonneural arteries 1–5.5 mm in diameter. Clinical indications included a wide range of vascular pathologic conditions (most commonly arteriovenous malformations [n = 20], renal angiomyolipomas [n = 8], and acute hemorrhage [n = 9]) and targeted visceral and musculoskeletal peripheral arteries. Data collected included sex, age, clinical indication, arterial pathology, arteries embolized, type of occlusion balloon microcatheter, type and concentration of EVOH agent, effectiveness as an embolic backstop, vessels protected, adequacy of EVOH cast penetration, catheter extraction, nontarget embolization, and complications.ResultsBalloon occlusion prevented EVOH reflux in 59 of 60 procedures (98.3%). Nontarget EVOH embolization occurred in 2 procedures (3.3%). Adequate EVOH cast penetration and complete filling of the target pathologic structure were seen in 57 of 60 procedures (95%). Balloon deflation and uneventful extraction occurred in all procedures; small EVOH fragments detached into target arteries in 2 cases. One major (1.7%) and 2 minor (3.3%) complications occurred.ConclusionsBalloon-assisted EVOH embolization of peripheral arteries is feasible, safe, effective, and versatile. The primary advantage of balloon-assisted EVOH embolization is the ability to apply more injection pressure to advance the EVOH cast assertively into the pathologic structure(s).     

Angiographic Findings Relevant to Prostatic Artery Embolization in Patients with Prostate Cancer

The 2014–2018 angiograms of 58 patients with prostate cancer were retrospectively analyzed to illustrate angiographic findings during prostatic artery embolization. Arteriovenous fistulae were observed in 6 patients (6/58, 10.3%), with no difference between patients with or without prior iodine-125 seeds implantation (5/48, 10.4% vs 1/10, 10.0%; P > .05); tumor staining was not detected. The origins of the prostatic arteries included the internal pudendal artery (n = 45, 32.4%), the superior vesical artery (n = 38, 27.3%), the obturator artery (n = 28, 20.1%), the gluteal-pudendal trunk (n = 21, 15.1%), the inferior gluteal artery (n = 3, 2.2%), the accessory pudendal artery (n = 3, 2.2%), and the superior gluteal artery (n = 1, 0.7%).     

Single-Center Retrospective Comparative Analysis of Transradial,Transbrachial, and Transfemoral Approach for Mesenteric Arterial Procedures

PurposeTo assess feasibility and safety of transradial access (TRA) compared with transfemoral access (TFA) and transbrachial access (TBA) for mesenteric arterial endovascular procedures.Materials and MethodsA retrospective cohort analysis was performed including all consecutive patients who underwent a mesenteric arterial procedure in a tertiary referral center between May 2012 and February 2018. Exclusion criteria were absence of data and lost to follow-up within 24 hours after the procedure. During the study period, 103 patients underwent 148 mesenteric arterial procedures (TBA, n = 52; TFA, n = 39; TRA, n = 57). Mean patient age was 64.3 years ± 13.3, and 91 patients (62%) were women. Primary outcomes were vascular access specified technical success rate and access site complication rate, as reported in hospital records.ResultsTechnical success rate specified for the vascular access technique did not differ between the 3 approaches (TBA 96%, TFA 87%, TRA 91%; TRA vs TBA, P = .295; TBA vs TFA, P = .112; TRA vs TFA, P = .524), and overall access site complication rate was not different between the 3 approaches (TBA 42%, TFA 23%, TRA 35%; TRA vs TBA, P = .439; TBA vs TFA, P = .055; TRA vs TFA, P = .208). However, more major access site complications were reported for TBA than for TRA or TFA (TBA 17%, TFA 3%, TRA 2%; TRA vs TBA, P = .005; TBA vs TFA, P = .026; TRA vs TFA, P = .785).ConclusionsTRA is a safe and feasible approach for mesenteric arterial procedures comparable to TFA, but with a significantly lower major access site complication rate than TBA.     

Safety and Efficacy of a Truncated Deflation Algorithm for Distal Transradial Access

PurposeTo assess safety and efficacy of a modified rapid hemostasis protocol for distal transradial access (TRA).Materials and MethodsA single-center retrospective study of patients undergoing percutaneous image-guided procedures from a distal TRA with rapid deflation hemostasis protocol was performed. Between March 2017 and August 2019, 593 procedures in 434 patients were performed. Mean patient age was 63.5 y (range, 18–94 y).ResultsThe most common procedures were transarterial chemoembolization (218; 36.8%), abdominal and pelvic embolization (116; 19.6%), yttrium-90 mapping (115; 19.4%), yttrium-90 administration (84; 14.2%), and diagnostic angiography (44; 7.4%). Mean (range) values for clotting parameters were international normalized ratio 1.2 (0.9–3.2), partial thromboplastin time 33.5 s (26–44 s), and platelets 23.4 × 10⁹/L (37–552 × 10⁹/L). A hematoma developed in 7 (1.2%) patients. No radial artery occlusions were encountered during follow-up. Nursing intensity was defined as the number of minutes after the procedure required for assessing and managing the access site for bleeding. The mean nursing intensity was 25.1 min (range, 25–40 min).ConclusionsThe rapid deflation hemostasis protocol for distal TRA at the anatomical snuffbox was feasible and safe. No significant difference or association was found between hematoma formation and clotting parameters after the procedure or type of vascular access equipment used.     

Iatrogenic Renal Artery Injury in 90 Cases: Arteriographic Findings and Outcomes after Embolization for Bleeding

PurposeTo evaluate differences in arteriographic findings and outcomes after embolization among patients with a suspected iatrogenic renal arterial injury (IRAI).Materials and MethodsPatients at the authors’ institution who underwent renal arteriography for suspected IRAIs after partial nephrectomy, biopsy, or percutaneous access over a 20-year period were included. Records, imaging, and outcomes were reviewed. Data analysis was performed using the Fisher exact or Kruskal-Wallis test.ResultsNinety arteriograms were performed on 83 patients after partial nephrectomy (n = 32), biopsy (n = 27), or percutaneous access (n = 24), including for nephrostomy/ureterostomy and stone removal. The median number of days between the index procedure and arteriogram was highest (15 days) after partial nephrectomy and lowest (5 days) after biopsy (P = .0001). Embolization was performed during 76% of arteriograms. If prearteriographic imaging showed positive results for IRAIs, embolization was performed in 67% versus 33% if imaging showed negative results (P = .005). The transfusion rate was higher after biopsy than after partial nephrectomy or percutaneous access (P = .002). Acute kidney injury after arteriogram occurred in 7% of patients; however, all returned to baseline by 1 week.ConclusionsDespite the different mechanism of IRAIs in partial nephrectomy, biopsy, and percutaneous access, arteriographic findings and outcomes were overall similar among groups. Prearteriographic imaging can help identify IRAIs but cannot supersede the clinical judgment regarding indication for embolization. IRAIs can present acutely or after a long interim, although patients who underwent biopsy presented earlier and more frequently required a blood transfusion. IRAIs can be treated with embolization without permanent deleterious effects on renal function.     

Safety and Efficacy of Arterially Directed Liver Therapies in the Treatment of Hepatic Metastatic Ovarian Cancer: A Retrospective Single-Institution Study

PurposeTo evaluate the safety and efficacy of 2 locoregional therapies (LRTs) including hepatic artery embolization (HAE) and transarterial radioembolization (TARE) in the treatment of patients with metastatic ovarian cancer to the liver.Material and MethodsFrom October 2010 to May 2019, the data of 15 consecutive patients (median age, 54 years ± 9.8; range, 35–78 years) with hepatic metastatic ovarian cancer who were treated with either HAE (n = 6; 40%) or TARE (n = 9; 60%) were reviewed. The most common histopathologic type was epithelial ovarian carcinoma (80%). The most common chemotherapy regimens used prior to embolization included carboplatin, paclitaxel, cisplatin, and bevacizumab. Patients received a mean of 4 lines ± 3 (range, 1–9) of chemotherapy. All patients with serous carcinoma were resistant to platinum at the time of embolization. Indications for embolization were progression of disease to the liver while receiving chemotherapy in 14 (93.3%) patients and palliative pain control in 1 patient.ResultsThe overall response rates at 1, 3, and 6 months were 92.4%, 85.6%, and 70%, respectively. Median overall survival from the time of LRT was 9 (95% confidence interval [CI], 4–14) months. Median local tumor progression was 6.4 months ± 5.03 (95% CI, 3.3–9.5). No grade 3–5 adverse events were detected in either group.ConclusionsHAE and TARE were well tolerated in patients with metastatic ovarian cancer to the liver and possibly ensured prolonged disease control in heavily treated, predominantly in patients resistant to platinum. Larger numbers are needed to verify these data.     

Clinical Results of Distal Embolization in Grade V Splenic Injury: Four-Year Experience from a Single Regional Trauma Center

PurposeTo evaluate the benefits and risks of splenic artery embolization (SAE) in patients with American Association for the Surgery of Trauma (AAST) grade V blunt spleen injury (BSI)Materials and MethodsMedical records of 88 patients treated with SAE between April 2013 and May 2017 at a regional trauma care center were reviewed retrospectively. The BSI grade according to the AAST spleen injury scale (revised version 2018) was determined by using computed tomography (CT) images. A total of 42 patients (46.6%) had AAST grade V injury and were included in the analysis. Patient demographics, angiographic findings, embolization techniques, and technical and clinical outcomes, including splenic salvage rate and procedure-related complications, were examined.ResultsSAE was performed within 2 hours after admission for 78.5% of the patients. All patients underwent selective distal embolization (n = 42). Primary clinical success rate was 80.9% (n = 34), and secondary clinical success rate was 88.1% (n = 37). The clinical failure group consisted of 5 patients. Four patients underwent splenectomy, and 1 patient died due to acute respiratory distress syndrome after embolization. The splenic salvage rate was 85.7% (n = 36). No patient had sepsis at follow-up (median, 247.0 days; interquartile range, 92.0–688.0). Clinical success rates (P = .356) and spleen salvage rates (P = .197) of patients who were hemodynamically stable (n = 19) showed no significant differences from those who were unstable (n = 23).ConclusionsDistal embolization of grade V BSI is a safe and feasible procedure which is effective for successful spleen salvage.     

Contemporary Management of Pediatric Blunt Splenic Trauma: A National Trauma Databank Analysis

PurposeTo quantify changes in the management of pediatric patients with isolated splenic injury from 2007 to 2015.Materials and MethodsPatients under 18 years old with registered splenic injury in the National Trauma Data Bank (2007–2015) were identified. Splenic injuries were categorized into 5 management types: nonoperative management (NOM), embolization, splenic repair, splenectomy, or a combination therapy. Linear mixed models accounting for confounding variables were used to examine the direct impact of management on length of stay (LOS), intensive care unit (ICU) days, and ventilator days.ResultsOf included patients (n = 24,128), 90.3% (n = 21,789), 5.6% (n = 1,361), and 2.7% (n = 640) had NOM, splenectomy, and embolization, respectively. From 2007 to 2015, the rate of embolization increased from 1.5% to 3.5%, and the rate of splenectomy decreased from 6.9% to 4.4%. Combining injury grades, NOM was associated with the shortest LOS (5.1 days), ICU days (1.9 days), and ventilator days (0.5 day). Moreover, splenectomy was associated with longer LOS (10.1 days), ICU days (4.5 days), and ventilator days (2.1 days) than NOM. The average failure rate of NOM was 1.5% (180 failures/12,378 cases). Average embolization failure was 1.3% (6 failures/456 cases). Splenic artery embolization was associated with lower mortality than splenectomy (OR: 0.10, P <.001). No statistically significant difference was observed in mortality between embolization and NOM (OR: 0.96, P = 1.0).ConclusionsIn pediatric splenic injury, NOM is the most utilized and associated with favorable outcomes, most notably in grades III to V pediatric splenic injury. If intervention is needed, embolization is effective and increasingly utilized most significantly in lower grade injuries.     

Where Have All the Punctures Gone? An Analysis of Thoracic Duct Embolizations

PurposeTo determine how frequently and how severely intra-abdominal structures are affected by transabdominal thoracic duct embolization (TDE).Materials and MethodsThirty-five TDE procedures in 35 patients (22 male; mean age, 57 y; age range, 10–79 y) with therapy-refractory chylous effusions were evaluated in which radiopaque embolization material outlined the access route on postinterventional CT. CT data were analyzed by 2 TDE-experienced radiologists. Abdominal structures and organs transgressed by the access route were recorded, and findings were correlated with clinical postinterventional course with follow-up of at least 44 days.ResultsIntra-abdominal structures/organs transgressed most often by the access route were the liver (n = 28), crus of the diaphragm (n = 25), pancreas (n = 14), portal vein (n = 10), duodenum (n = 7), inferior vena cava (n = 5), colon (n = 3), left renal vein (n = 2), pleura (n = 2), pericardium (n = 2), and gastric sleeve (n = 2). Pancreatitis was observed in 1 of 14 patients after pancreatic transgression. One case of clinically occult pulmonary glue migration occurred on catheter pullback through the left renal vein. Biliary peritonitis was observed after gallbladder puncture, necessitating cholecystectomy in 1 of 2 transbiliary punctures. No other relevant procedure-related complications such as hemorrhages or infectious complications were observed.ConclusionsDespite transgression of intra-abdominal structures, puncture- and access-related complications of TDE are rare. Transpancreatic manipulations are reasonably well tolerated.     

Biodegradable Polydioxanone Microspheres for Transcatheter Arterial Embolization: Proof of Principle

PurposeTo evaluate feasibility, embolization success, biodegradability, reperfusion, and biocompatibility of biodegradable microspheres (MS) made from polydioxanone (PDO) for transcatheter arterial embolization.Materials and MethodsUnilateral selective renal embolization of a segmental artery was performed in 16 New Zealand White rabbits with PDO-MS (100–150 μm and 90–315 μm). Animals were randomly assigned to different observation periods and underwent control digital subtraction angiography (DSA) and MR imaging immediately (n = 3), 1 week (n = 2), 4 weeks (n = 2), 8 weeks (n = 2), 12 weeks (n = 5), and 16 weeks (n = 2) after embolization. Kidneys were harvested for macroscopic and histologic analysis of embolization success, biodegradability, and biocompatibility.ResultsEmbolization was technically successful in 15 of 16 animals. One animal died of anesthesia-related circulatory failure. The 100–150 μm MS were injected easily through 3-F catheters; the 90–315 μm MS tended to clog with intermittent catheter obstruction. DSA and MR imaging showed successful target embolization in 13 of 15 animals. In 2 animals, the entire kidney was affected owing to catheter clogging, including a reflux of MS while flushing. Control DSA and MR imaging showed increasing vascular reperfusion with time. Macroscopic and histologic analysis revealed necrosis/infarction in areas in which embolization was achieved. MS were extensively degraded after 16 weeks, and overall inflammatory reaction was mild.ConclusionsBiodegradable PDO-MS induced effective embolization of target vessels while demonstrating good biocompatibility. MS increasingly dissolved at 16 weeks, partial reperfusion started at week 1, and complete reperfusion started at week 8, thus offering possible advantages as a temporary embolic agent.     

The Use of an Inflatable Adhesive External Compression Device for Maintenance of Hemostasis following Angiography in Children

PurposeTo assess the safety and efficacy of the posthemostasis use of an inflatable adhesive external compression device (SafeGuard) following angiography in children performed under general anesthesia.Materials and MethodsMedical records of 74 children (43 females) with a mean age of 8.9 years (range, 0.4–18.0 years) and mean weight of 44.0 kg (range, 7.3–115.7 kg) in whom an inflatable adhesive external compression device was used for maintaining hemostasis following angiography under general anesthesia were retrospectively reviewed. After establishing hemostasis with manual compression, the device was applied and inflated over the arteriotomy. The patients were assessed for access-related adverse events in the recovery unit and during postprocedural follow-up.ResultsThe inflatable adhesive external compression device was utilized to maintain hemostasis following 181 angiography procedures. The mean length of the procedure was 396 minutes. The common femoral artery (n = 170, 93.9%) was the most common access, using 4–5-F vascular sheath (n = 118, 65.2%) or 3–5-F sheathless (n = 8, 12.7%) catheters. The mean time to deflation was 93 minutes. There were no adverse events other than minor bleeding from the arteriotomy after deflation (n = 2, 1.1%) and early deflation of the device because of pain (n = 1, <1%). Follow-up ultrasonography (n = 109 procedures, 60.2% at a mean follow-up of 2.2 years) demonstrated patency of the access artery.ConclusionsThe use of an inflatable adhesive external compression device following angiography in children to maintain hemostasis during the emergence phase of anesthesia and recovery period is safe and effective. The use of this simple device may reduce the need for postprocedural sedation and facilitate early discharge.     

Endovascular Pressure Measurements to Assess the Functional Severity of Mesenteric Arterial Stenoses

PurposeTo assess the ability of pressure measurements to discriminate clinically significant celiac artery (CA) or superior mesenteric artery (SMA) stenosis in patients with suspected chronic mesenteric ischemia (CMI).Materials and MethodsSingle-center, retrospective cohort study of 41 intra-arterial pressure measurements during mesenteric angiography with intended revascularization, performed in 37 patients (mean age 67.7 ± 10.8 years, 62% female) between April 2015 and May 2017. Simultaneous prestenotic and poststenotic pressure measurements had been obtained before and after intra-arterial administration of nitroglycerin. Revascularization was performed in 38 of 41 procedures. Definitive diagnosis of CMI was defined as patient-reported symptom relief or improvement after successful revascularization.ResultsPressure gradients obtained after vasodilator administration were significantly higher in CAs and SMAs with ≥50% stenosis. Pressure ratios (pressure distal [Pd]/pressure aorta [Pa]) obtained after vasodilator administration were significantly higher in CAs with ≥50% stenosis. Subgroup analysis of 22 patients with a ≥50% stenosis of either CA or SMA showed significantly higher pressure gradients and Pd/Pa ratios after vasodilator administration in CMI patients (median pressure gradient: CMI [interquartile ratio] 36 [21-40] mm Hg versus no-CMI 20 [9-21] mm Hg, P = 0.041; Pd/Pa: CMI 0.703 [0.598-0.769] versus no-CMI 0.827 [0.818-0.906], P = .009). A ≤0.8 Pd/Pa cutoff value after administration of a vasodilator best identified a clinically relevant stenosis, with 86% sensitivity and 83% specificity. Complications related to the pressure measurements were not observed.ConclusionsIntra-arterial pressure measurements are feasible and safe. Low Pd/Pa ratios were associated with clinically relevant CA or SMA stenosis.     

A Rat Model of Frozen Shoulder Demonstrating the Effect of Transcatheter Arterial Embolization on Angiography,Histopathology, and Physical Activity

PurposeTo assess the angiographic findings and the effects of transcatheter arterial embolization on physical activity and histopathology using a frozen shoulder rat model.Materials and MethodsFirst, the angiographic and histopathologic findings of rats in which the shoulder was immobilized with molding plaster for 6 weeks (n = 4) were compared to control rats with normal non-immobilized shoulders (n = 4). Next, a total of 16 frozen shoulder rats were divided into 2 groups. In the transcatheter arterial embolization group (n = 8), imipenem/cilastatin was injected into the left thoracoacromial artery. The changes of physical activity before and after procedures were evaluated and compared with a saline-injected control group (n = 8). Histopathologic findings were also compared between the 2 groups.ResultsAngiography revealed abnormal shoulder staining in all of the rats with a frozen shoulder. On histopathology, the numbers of microvessels and mononuclear inflammatory cells in the synovial membrane of the joint capsule were significantly higher compared with the control rats (both P = .03). In the transcatheter arterial embolization group, the running distance and speed were improved (P = .03 and P = .01, respectively), whereas there were no significant differences in the control group. The number of microvessels and mononuclear inflammatory cells in the transcatheter arterial embolization group were significantly lower than the control group (P = .002 and P = .001, respectively).ConclusionsThe rat frozen shoulder model revealed the development of neovascularization. Transcatheter arterial embolization decreased the number of blood vessels and inflammatory changes in the frozen shoulder and increased the moving distance and speed of the rats.