Treatment of Aortoiliac Occlusive Lesions by Aortic Robotic Surgery: Learning Curve and Midterm Outcome.

BACKGROUD: The learning curve and midterm results of aortoiliac occlusive disease (AIOD) revascularization by robot-assisted laparoscopic (RAL) surgery may be known. METHODS: A prospective single-center study was conducted in the vascular surgery department of Georges Pompidou European Hospital (Paris, France). Patients with AIOD treated by RAL from February 2014 to February 2019 were included. Demographic characteristics, past medical history, Trans-Atlantic Inter-Society Consensus (TASC) lesions classifications, mortality, primary and secondary patency, as well as complication rates were collected. Safety was analyzed by the cumulative sum control chart method with a conversion rate of 10%, operative time by cumulative average-time model, and primary and secondary patency by the Kaplan-Meier method. RESULTS: Seventy patients were included, 18 (25.7%) with TASC C lesions and 52 (74.3%) with TASC D lesions. Before discharge, 14 (24.3%) patients had surgical complications. Among them, 10 (14.3%) required at least one reintervention. One (1.4%) patient died during the hospitalization. The learning curve in terms of safety (conversion rate) was 13 cases with an operating time of 220 minutes after 35 patients. During follow-up (median 37 months [21; 49]), 63 patients (91.3%) improved their symptoms, 53 (76.8%) became asymptomatic, and 3 graft limb occlusions occurred. The primary patency at 12, 24, 36, and 48 months was 94%, 92%, 92%, and 92%, respectively, while the secondary patency for the same intervals was 100%, 98.1%, 98.1%, and 98.1%, respectively. CONCLUSIONS: Robotic surgery in AIOD revascularization seems safe and effective; allowing to treat patients with few comorbidities and severe lesions, in a dedicated center experienced in RAL, with excellent patency. Prospective clinical trials should be performed to confirm safety.

Technical Risk Stratification Nomogram Model for 90-Day Mortality Prediction in Patients With Acute Basilar Artery Occlusion Undergoing Endovascular Thrombectomy: A Multicenter Cohort Study.

BACKGROUND: This study aimed to establish and validate a nomogram model for predicting 90-day mortality in patients with acute basilar artery occlusion receiving endovascular thrombectomy. METHODS AND RESULTS: A total of 242 patients with basilar artery occlusion undergoing endovascular thrombectomy were enrolled in our study, in which 172 patients from 3 stroke centers were assigned to the training cohort, and 70 patients from another center were assigned to the validation cohort. Univariate and multivariate logistic regression analyses were adopted to screen prognostic predictors, and those with significance were subjected to establish a nomogram model in the training cohort. The discriminative accuracy, calibration, and clinical usefulness of the nomogram model was verified in the internal and external cohorts. Six variables, including age, baseline National Institutes of Health Stroke Scale score, Posterior Circulation-Alberta Stroke Program Early CT (Computed Tomography) score, Basilar Artery on Computed Tomography Angiography score, recanalization failure, and symptomatic intracranial hemorrhage, were identified as independent predictors of 90-day mortality of patients with basilar artery occlusion and were subjected to develop a nomogram model. The nomogram model exhibited good discrimination, calibration, and clinical usefulness in both the internal and the external cohorts. Additionally, patients were divided into low-, moderate-, and high-risk groups based on the risk-stratified nomogram model. CONCLUSIONS: Our study proposed a novel nomogram model that could effectively predict 90-day mortality of patients with basilar artery occlusion after endovascular thrombectomy and stratify patients with high, moderate, or low risk, which has a potential to facilitate prognostic judgment and clinical management of stroke.

Endovascular Therapy for Vascular Graft Infection After Multiple Bypass Surgeries for Aorto-Iliac Occlusive Disease.

BACKGROUND: Vascular graft infection is a very complex disease. Although complete excision of the infected grafts with extra-anatomic bypass or in situ reconstruction is a general treatment strategy, some concerns including reinfection in the new graft remain. CASE REPORT: An 88 year-old man presented to the hospital with abdominal swelling and bleeding. The patient had undergone revascularization for aorto-iliac occlusive disease twice in the past. The first procedure had been performed 15 years previously, with right ilio-femoral bypass grafting for right iliac artery occlusion and stent implantation for left iliac artery stenosis. The second procedure had been performed 10 years previously, with aorta-to-left femoral and left-to-right femoro-femoral bypass grafting because the terminal aorta, the first ilio-femoral bypass graft, and the stent of the left iliac artery had been occluded. The patient was diagnosed with vascular graft infection, and endovascular therapy was selected as the revascularization method prior to graft excision. It was successfully performed using various devices and techniques, followed by graft excision without critical limb ischemia. CONCLUSION: This case demonstrates that endovascular therapy prior to graft excision can be an alternative revascularization method for vascular graft infection after bypass surgery for aorto-iliac occlusive disease.

Endovascular Treatment as an Alternative to Bypass Surgery for Juxtarenal Aortic Occlusion: Results from the CHAOS (CHronic Abdominal Aortic Occlusion, ASian Multicenter) Registry.

BACKGROUND: Juxtarenal aortic occlusion (JRAO), in which the occlusion of the aorta extends to just below the renal artery, is often treated by bypass surgery because of concerns about the risk of procedural failure and fatal embolization to abdominal organs when treated with endovascular treatment (EVT). This study assessed the outcome of EVT for JRAO compared with aorto-biiliac /aorto-bifemoral (AOB) or axillo-bifemoral (AXB) bypass. METHODS: A retrospective review of an international database created by 30 centers in Asia (CHronic Abdominal Aortic Occlusion, ASian Multicenter registry) was performed for patients who underwent revascularization for chronic total occlusion of the infrarenal aorta from 2007 to 2017. Of the 436 patients, 130 with JRAO (Forty-seven AOBs, 32 AXBs, and 51 EVTs) from 25 institutions were included in this study. RESULTS: Patients were significantly older in the AXB and EVT groups and more malnourished in the EVT group than the AOB group. EVT was attempted but failed in 1 patient. Seven patients (1 [2.1%] in the AOB group, 1 [3.1%] in the AXB group, and 5 [9.8%] in the EVT group) died during hospitalization, but most of the causes in the EVT group were not related to the revascularization procedure. No visceral embolism was observed, which had been concerned, even though protection was performed only in 2 cases of the EVT group. At the latest follow-up (median duration 3.0 years), the ankle-brachial pressure index was significantly higher in the order of AOB, EVT, and AXB. At 4 years, the estimated primary and secondary patency rates of the AOB group (87.5% and 90.3%, respectively) were significantly higher than the AXB group (66.7% and 68.6%, respectively). CONCLUSIONS: AOB remains the gold standard and should be the first choice for acceptable risk patients. For frail patients, EVT is a good option and likely preferable as a first-line treatment compared to AXB.

Trials of endovascular thrombectomy of basilar-artery occlusion compared to real-life data.

BACKGROUND: Two recent clinical trials showed mechanical thrombectomy (MT) of basilar-artery occlusions (BAO) in stroke to be safe and effective: Endovascular Treatment for Acute BAO (ATTENTION) and BAO Chinese Endovascular (BAOCHE). The trials restricted patient inclusion on both age and pre-stroke mRS, and with both trials conducted in China, population differences may affect generalisability of the trial results. METHODS: Consecutive patients with BAO undergoing MT were registered from 2017 to 2021 with retrospective data collection at a single centre with a predominantly Caucasian catchment population of 2.7 million. Age and pre-stroke modified Rankin Scale (mRS) were not absolute contraindications for MT. We present functional outcome as mRS at 90 days, patient characteristics and procedural safety compared to the trial intervention groups. RESULTS: Of the 108 included patients, 50 % achieved mRS 0-3 at 90 days and mortality was 32 %, which was no different from ATTENTION (46 %, p = 0.40, 37 %, p = 0.31, respectively) and BAOCHE (46 %, p = 0.50, 31 %, p = 0.93). Pre-stroke mRS 0 was seen in 62 %, 89 %, and 77 % of the study patients, ATTENTION, and BAOCHE, respectively. Proximal segment BAO was less common (22 % vs. 31 %, p = 0.04, and 65 %, p < 0.01) and intracranial stenting less frequently used (9 % vs. 40 % and 55 %, p < 0.01) in study patients compared to ATTENTION and BAOCHE, respectively. CONCLUSION: Outcome of MT in BAO stroke in a clinical patient cohort was similar to recent trials, despite broader patient inclusion and differences in both occluded BAO segment and use of stenting. Our study suggest that MT is safe and effective in a Caucasian population.

Improving duplex ultrasound methods for diagnosing functional popliteal artery entrapment syndrome.

OBJECTIVES: Popliteal artery entrapment syndrome (PAES) is a rare condition where musculoskeletal structures compress the popliteal artery (POPA) leading to vascular compromise. This study investigates the effect of dynamic plantar- and dorsi-flexion loading on POPA hemodynamic parameters to develop a robust diagnostic ultrasound-based protocol for diagnosing functional PAES. METHODS: Healthy individuals (n = 20), recreational athletes (n = 20), and symptomatic (n = 20) PAES patients were consented. Triplex ultrasound imaging of lower limb arteries was performed (n = 120 limbs). Proximal and distal POPA's in dorsi-/plantar-flexion, in prone and erect positions, were imaged at rest and flexion. Peak systolic velocities (cm/s) and vessel diameter (antero-posterior, cm) was measured. RESULTS: Distal vessel occlusion was noted across all three groups whilst prone during plantar-flexion (62.7%). POPA occlusion was only noted in the proximal vessel within the patient group (15.8%). When prone, 50% of control (n = 40 limbs), 70% of athletes (n = 40 limbs), and 65% of patients (n = 40 limbs) had distal POPA occlusion in plantar-flexion. When prone, recreational athletes (5%), and patients (12.5%) had distal POPA compression under dorsi-flexion. POPA occlusions with the patient in erect position were only noted in the symptomatic patient group under both dorsi-flexion (15.8%) and plantar-flexion (23.7%). CONCLUSION: Compression of the POPA on ultrasound should not be the sole diagnostic criteria for PAES. POPA compression exists in asymptomatic individuals, primarily under prone plantar-flexion. To reduce false positives, ultrasound-based protocols should focus on scanning patients in the erect position only to diagnose PAES, rather than asymptomatic POPA compression. A distinction should be made between the two.

Adjunct Intraarterial or Intravenous Tirofiban Versus No Tirofiban After Successful Recanalization of Basilar Artery Occlusion Stroke: The BASILAR Registry.

BACKGROUND: Approximately half of patients who achieve successful reperfusion do not achieve functional independence. The present study sought to investigate the clinical outcomes and safety of intraarterial or intravenous tirofiban as adjunct therapy in patients with acute basilar artery occlusion who had achieved successful recanalization with endovascular treatment. METHODS AND RESULTS: In the national, prospective BASILAR (Endovascular Treatment for Acute Basilar Artery Occlusion Study) registry, 458 patients who met inclusion criteria were divided into 3 groups based on tirofiban administration (no tirofiban, n=262; intravenous tirofiban, n=101; intraarterial+intravenous tirofiban, n=95). Their clinical outcomes were compared with 90-day modified Rankin Scale scores. Adjusted odds ratios (aORs) and 95% CIs were obtained by logistic regression models and propensity score matching. Safety outcomes included any intracranial hemorrhage (ICH), symptomatic ICH, and mortality. Among 458 included patients, 184 (40.2%) achieved a favorable outcome (modified Rankin Scale score 0-3). There were no differences between the intravenous tirofiban group and the no tirofiban group in terms of safety and clinical outcomes (all P>0.05). Compared with the no tirofiban group, the intraarterial+intravenous tirofiban group had higher odds of 90-day modified Rankin Scale score 0 to 3 (aOR, 2.44 [95% CI, 1.30-4.64], P=0.006) and lower 3-month mortality (aOR, 0.38 [95% CI, 0.19-0.71], P=0.002) without an increase in any ICH (aOR, 0.34 [95% CI, 0.09-1.01], P=0.07) or symptomatic ICH (aOR, 0.23 [95% CI, 0.03-0.90], P=0.05). Similar results of intraarterial+intravenous tirofiban on improving clinical outcomes were detected in novel cohorts constructed by propensity score matching. CONCLUSIONS: Intraarterial+intravenous rather than intravenous tirofiban improved clinical outcomes without increasing the frequency of symptomatic ICH among patients with basilar artery occlusion after successful endovascular treatment. Further studies are needed to delineate the roles of intraarterial+intravenous tirofiban in patients with basilar artery occlusion receiving endovascular treatment.

Safety and Efficacy of Stent-Graft in the Treatment of Aortoiliac Artery Occlusive Disease: A Multicenter Study of Short-Term and Medium-Term Outcomes.

BACKGROUND: To evaluate the short-term and mid-term safety and efficacy of stent-graft compared with bare stents for treatment of aortoiliac occlusive disease (AIOD). METHODS: One hundred eighty three patients diagnosed with AIOD who received stent implantation at 3 vascular centers in north China between January 2019 and December 2021 were enrolled. Patients were divided into those undergoing stent-graft (Group A; n = 67) or bare stent (Group B; n = 116) implantation for retrospective cohort analysis. Efficacy was assessed as surgical success rate and rate of freedom from clinically driven target lesion reintervention at each follow-up time point. Safety was assessed by the rate of perioperative complication, major limb amputation, and aortoiliac artery-related mortality. RESULTS: There were no preoperative baseline differences between the 2 groups (P > 0.05). The surgical success was 91.04% for Group A, significantly higher than that for Group B (79.31%; P < 0.05). Incidence of perioperative complications was 2.98% for Group A, significantly lower than that for Group B (9.48%, P < 0.05), as was the rate of major limb amputation (A: 1.49% vs. B: 5.17%) and aortoiliac artery-related mortality (A: 1.49% vs. B: 4.31%), although these 2 indicators were not significantly different (P > 0.05). Follow-up rates were 91.8% for the total follow-up time of 3 years. Kaplan-Meier survival curve analysis gave significantly higher 1-year and 2-year freedom from clinically driven target lesion reintervention for Group A (98.51% and 95.52%) than for Group B (95.69% and 89.66%, P < 0.05). CONCLUSIONS: Stent-graft is more effective and safer than bare stent in the treatment of AIOD.

Contemporary outcomes of surgical decompression for functional popliteal entrapment syndrome.

BACKGROUND: Functional popliteal entrapment syndrome (FPES) is an under-recognized source of leg pain caused by dynamic compression of the popliteal vessels by surrounding musculature in the absence of anatomic abnormality. Late recognition and difficulty capturing this entity across imaging modalities can lead to significant morbidity in an often young and active patient population. Surgical outcomes and optimal diagnostic strategies remain uncertain. METHODS: We performed a retrospective cohort study of all patients undergoing surgical decompression for FPES at an academic medical center between 2018 and 2022. Preoperative symptoms, patient characteristics, imaging, operative details, and follow-up were captured. The primary outcome was symptomatic improvement at last clinic visit. Secondary outcomes included symptomatic improvement at 6 months and postoperative complications. RESULTS: A total of 24 extremities (16 patients) were included. The mean ± standard deviation age was 23.3 ± 6.4 years and 75.0% of patients were female. The median symptom duration before decompression was 27 months (interquartile range, 10.7-74.6 months). Preoperative symptom severity in the affected extremity was as follows: 33.3% limited from peak exercise, 25% unable to exercise, and 41.7% with debilitating symptoms that affected activities of daily living. Preoperative imaging with provocative maneuvers included duplex ultrasound (87.5%), magnetic resonance angiography (100%), and digital subtraction angiography (100%). Using digital subtraction angiography as the gold standard, the sensitivity for detection of FPES was 85.7% for duplex examination and 58.3% for magnetic resonance angiography. The median follow-up was 451 days (interquartile range, 281-635 days). Most patients demonstrated durable improvement in the affected extremity, with 29.2% realizing complete resolution of symptoms and 37.5% reporting symptomatic improvement at last clinic visit for a total of 66.7%; 20.8% had initial improvement, but developed recurrent symptoms and were found to have elevated compartment pressures consistent with chronic exertional compartment syndrome and were treated with formal fasciotomy. Repeat decompression was required in one extremity (4.2%) owing to recurrent symptoms. Two patients (8.3%) had minimal or no improvement in their affected extremity and workup for the cause of continued discomfort was ongoing. CONCLUSIONS: Delays in diagnosis of FPES are common. Provocative maneuvers until replication of symptoms across multiple imaging modalities may be necessary to reliably identify the disease process. Surgical decompression improved or completely resolved symptoms in two-thirds of extremities. Treating physicians should maintain suspicion for comorbid chronic exertional compartment syndrome, especially if symptoms recur or persist after decompression.

Comparison of long-term radial artery occlusion via distal vs. conventional transradial access (CONDITION): a randomized controlled trial.

BACKGROUND: The distal transradial access (dTRA) has become an attractive and alternative access to the conventional transradial access (TRA) for cardiovascular interventional diagnosis and/or treatment. There was a lack of randomized clinical trials to evaluate the effect of the dTRA on the long-term radial artery occlusion (RAO). METHODS: This was a prospective, randomized controlled study. The primary endpoint was the incidence of long-term RAO at 3 months after discharge. The secondary endpoints included the successful puncture rate, puncture time, and other access-related complications. RESULTS: The incidence of long-term RAO was 0.8% (3/361) for dTRA and 3.3% (12/365) for TRA (risk ratio = 0.25, 95% confidence interval = 0.07-0.88, P = 0.02). The incidence of RAO at 24 h was significantly lower in the dTRA group than in the TRA group (2.5% vs. 6.7%, P < 0.01). The puncture success rate (96.0% vs. 98.5%, P = 0.03) and single puncture attempt (70.9% vs. 83.9%, P < 0.01) were significantly lower in the dTRA group than in the TRA group. However, the number of puncture attempts and puncture time were higher in the dTRA group. The dTRA group had a lower incidence of bleeding than the TRA group (1.5% vs. 6.0%, P < 0.01). There was no difference in the success rate of the procedure, total fluoroscopy time, or incidence of other access-related complications between the two groups. In the per-protocol analysis, the incidence of mEASY type ≥ II haematoma was significantly lower in the dTRA group, which was consistent with that in the as-treated analysis. CONCLUSIONS: The dTRA significantly reduced the incidence of long-term RAO, bleeding or haematoma. TRIAL REGISTRATION: ClinicalTrials.gov identifer: NCT05253820.

Feasibility of early radial artery occlusion recanalization and reuse through transradial access for neuroendovascular procedures.

BACKGROUND: Radial artery occlusion (RAO) remains a significant limitation of neuroendovascular procedures peformed through transradial access (TRA) when radial artery needs to be reused. Instances of early RAO recanalization to successfully complete neuroendovascular procedures have been rarely documented. MATERIALS AND METHODS: Documents and imaging data were extracted retrospectively for all patients who underwent TRA diagnostic angiography and neuroendovascular procedures in our center from June 2022 to February 2023. The patients with early RAO who required repeat TRA were included. RESULTS: A total of 46 patients underwent repeat TRA, and 13 consecutive patients who experienced early RAO after angiography as confirmed by ultrasonography were enrolled in this study. The occluded radial arteries were successfully recanalized, and subsequent neuroendovascular procedures were carried out successful. During an average follow-up time of 7.1 months, no patients exhibited symptomatic RAO, dissection, hematoma or pseudoaneurysm. CONCLUSIONS: Early RAO recanalization and reused for neuroendovascular procedures through TRA is feasible. A visually guided and stable puncture process plays a crucial role in successfully recanalizing early RAO.

The morphology of occlusion stump for endovascular recanalization in non-acute vertebral ostial occlusion.

PURPOSE: Non-acute vertebral ostial occlusion (VOO) is a debilitating condition with significant mortality and morbidity rates. However, currently, there is no consensus on the optimal treatment strategy for VOO. This study aims to examine the feasibility, effectiveness, and safety of endovascular recanalization in patients with VOO. METHODS: We conducted a retrospective review of data from 21 consecutive patients with VOO who underwent endovascular recanalization between May 2018 and August 2023. The patients were divided into two groups based on a new angiographic classification proposed by Gao et al. Type I (tapered stump group) included patients with non-acute extracranial vertebral artery ostial occlusion presenting a tapered occlusion stump. Type II (nontapered stump group) consisted of patients with a nontapered occlusion stump. We collected data on recanalization rates, perioperative complications, and follow-up outcomes. RESULTS: Our analysis included data from a total of 21 patients (22 lesions) with a mean age of 64.6 ± 10.6 years. The technical success rate was 66.7 % (14/21), and the rate of periprocedural complications was 14.3 % (3/21). The success rate of transitioning from the tapered stump group to the nontapered stump group was 90.9 % (10/11) and 40 % (4/10), respectively (P = 0.024). The perioperative complication rate for type I and type II patients was 18.2 % (2/11) and 10 % (1/10), respectively. Among these patients, 18 cases underwent endovascular recanalization using transfemoral access, while 3 patients underwent transradial access after failed transfemoral access, with successful outcomes for two patients. CONCLUSIONS: This study suggests that endovascular recanalization may offer a safe, effective, and feasible treatment option for VOO patients. Additionally, the proposed angiographic classification may serve as a useful guide in selecting suitable candidates for surgery.

White matter hyperintensity burden and collateral circulation in acute ischemic stroke with large artery occlusion.

OBJECTIVE: This study aimed to investigate the association between white matter hyperintensity (WMH) burden and pial collaterals in acute strokes caused by intracranial large artery occlusion treated with mechanical thrombectomy in the anterior circulation, focusing on stroke subtypes. METHODS: Consecutive patients undergoing mechanical thrombectomy between December 2019 and June 2022 were retrospectively screened. The Fazekas scale assessed WMH burden. Pial collaterals were categorized as either poor (0-2) or good (3-4) based on the Higashida score. A multivariable analysis was used to determine the relationship between WMH burden and pial collaterals. Subgroup analyses delved into associations stratified by stroke subtypes, namely cardioembolism (CE), tandem lesions (TLs), and intracranial atherosclerosis (ICAS). RESULTS: Of the 573 patients included, 274 (47.8%) demonstrated poor pial collaterals. Multivariable regression indicated a strong association between extensive WMH burden (Fazekas score of 3-6) and poor collaterals [adjusted OR 3.04, 95% CI 1.70-5.46, P < 0.001]. Additional independent predictors of poor collaterals encompassed ICAS-related occlusion (aOR 0.26, 95% CI 0.09-0.76, P = 0.014), female sex (aOR 0.63, 95% CI 0.41-0.96, P = 0.031), and baseline Alberta Stroke Program Early Computed Tomography scores (aOR 0.80, 95% CI 0.74-0.88, P < 0.001). Notably, an interaction between extensive WMH burden and stroke subtypes was observed in predicting poor collaterals (P = 0.001), being pronounced for CE (adjusted OR 2.30, 95% CI 1.21-4.37) and TLs (adjusted OR 5.09, 95% CI 2.32-11.16), but was absent in ICAS (adjusted OR 1.24, 95% CI 0.65-2.36). CONCLUSIONS: Among patients treated with mechanical thrombectomy for anterior circulation large artery occlusion, extensive WMH burden correlates with poor pial collaterals in embolic occlusion cases (CE and TLs), but not in ICAS-related occlusion.

Transient Hemichorea-hemiballism Induced by a Combination of Postprandial Hypotension and Severe Stenosis of the Innominate Artery Concomitant with Left Carotid Occlusion.

Hemichorea-hemiballism (HCHB) due to transient ischemic attacks (TIAs) is rare. An 83-year-old woman had repeated episodes of right-sided HCHB for 3 months. Magnetic resonance (MR) angiography demonstrated occlusion of the left carotid and middle cerebral arteries and severe stenosis of the innominate artery, and 24-hour ambulatory blood pressure monitoring showed a blood pressure decrease of >20 mmHg after each meal. We speculated that HCHB developed as TIAs due to hemodynamic failure in the left cerebral hemisphere, caused by a combination of severe stenosis of the innominate artery concomitant with occlusion of the left carotid and middle cerebral arteries as well as postprandial hypotension.

Evaluation of the Relationship Between Radial Artery Intima Media Thickness and Complications at the Intervention Site After Radial Angiography.

The present study investigated the relationship between pre-procedural radial intima-media thickness (rIMT) and radial artery thrombosis (RAO) in patients undergoing angiography using a transradial approach (TRA). Patients (n = 90) who underwent cerebral or peripheral arterial angiography using TRA were included in the study. Ultrasonographic evaluation was performed before and 12 h after the procedure. Preoperative rIMT measurement was performed at the distal radial artery. Presence of radial artery occlusion was evaluated by ultrasonography after radial catheterization and revealed occlusive thrombus in the radial artery in 13 patients. rIMT was found to be statistically significantly higher in patients with thrombus (P < .05). When it was evaluated whether there was a correlation between age and rIMT, a positive significant correlation was found (P < .01). Our study suggests that increase of rIMT may be a risk factor for RAO in the intervention area. Before the procedure, ultrasound (US) assessment of the radial artery may be useful in determining the risk of occlusion. Thus, RAO-related technical risk factors (procedure time, number of punctures, sheath thickness, etc.) can be managed more carefully in patients having radial angiography.