Distal transradial access in the anatomical snuffbox for diagnostic cerebral angiography

Distal versus proximal transradial access for diagnostic cerebral angiography: A single-center experience

BACKGROUND

To compare the safety and effectiveness of cerebral angiography via distal transradial access puncture (dTRA) versus proximal radial artery puncture (pTRA).

METHODS

A total of 494 patients undergoing cerebral angiography were randomly assigned to either the dTRA or pTRA groups in a 1:1 ratio. The study evaluated puncture success rates, puncture time, procedural fluoroscopy time, operation time, and the incidence of complications between the two groups.

RESULTS

The success rate for dTRA was 92.7 % (229/247), compared to 99.19 % (245/247) for pTRA. In cases where dTRA failed, switching to pTRA achieved a 100 % success rate (18/18). The average puncture time for dTRA was 6.61 ± 4.12 min (p = 0.021), compared to 5.74 ± 4.12 min for pTRA. Fluoroscopy time was 8.03 ± 3.50 min for dTRA and 8.18 ± 3.30 min for pTRA (p = 0.639). The procedural operation time was 17.33 ± 5.38 min for dTRA and 16.84 ± 5.11 min for pTRA (p = 0.32). The incidence of radial artery occlusion, hand edema, and subcutaneous hematoma was significantly lower in the dTRA group compared to the pTRA group.

CONCLUSIONS

Cerebral angiography via the dTRA approach is safe and effective, with a lower incidence of radial artery occlusion. Failure of dTRA does not preclude subsequent successful pTRA, making dTRA a viable option for cerebral angiography.

Decreased Incidence of Radial Artery Vasospasm Using a Distal Transradial Approach in Diagnostic Cerebral Angiography: A Comparison of 200 Consecutive Cases

BACKGROUND AND OBJECTIVES

Radial artery vasospasm is a common complication of radial artery catheterization. During the implementation of distal transradial approach (dTRA), we observed a decreased incidence of radial artery vasospasm on radial artery angiography following access that was not well detailed in the literature. The purpose of this study was to characterize the phenomenon of radial artery vasospasm in the context of different radial artery access points for diagnostic cerebral angiography.

METHODS

We retrospectively reviewed consecutive patients undergoing diagnostic cerebral angiography from September 2023 to March 2024. Hundred conventional transradial approach (cTRA) and 100 dTRA diagnostic cerebral angiograms were performed. Following sheath insertion, all angiographic runs were reviewed, and a classification scheme was used to detail radial artery vasospasm occurrence.

RESULTS

Radial artery vasospasm was lower in the dTRA approach compared with the cTRA approach ( P = .019). A change in radial artery diameter was noted in 47 (47%) patients in the cTRA group vs 28 (28%) patients in the dTRA group. Radial artery diameter distal to the sheath was smaller in the cTRA group (2.30 ± 0.41) compared with the dTRA group (2.42 ± 0.48) ( P = .021). Patients with Grade II/III spasm were younger (58 years vs 62 years; P = .029) and had a higher percentage of females (77.3% vs 62.4%; P = .030). Grade II/III spasm patients had a higher percentage of the cTRA approach compared with the dTRA approach (62.7% vs 42.4%; P = .008). These procedures were significantly longer with Grade II/III procedure time of 18:00 minutes vs 15.59 minutes in the Grade I group. Number of vessels catheterized was not significantly different between groups ( P = .262).

CONCLUSION

dTRA for diagnostic cerebral angiography is associated with a lower incidence of radial artery vasospasm compared with cTRA. Operators seeking to obviate radial artery vasospasm may consider using the dTRA approach for diagnostic cerebral angiography.

Preliminary Experience With Novel Straight 3-Fr Guiding Sheath for Transradial Access in Endovascular Treatment: Feasibility and Safety

BACKGROUND AND OBJECTIVES

Radial artery diameter may limit whether a guiding sheath (GS) can be used via transradial artery access (TRA). A smaller GS may reduce the risk of access site-related complications. This study investigated the feasibility and safety of endovascular treatment (EVT) using a straight-shaped 3-Fr GS (Axcelguide; Medikit).

METHODS

Patients who underwent EVT with a straight-shaped 3-Fr GS at 3 institutions between April 2022 and March 2024 were retrospectively reviewed. Patient background, anatomic and procedural factors, and complications were recorded.

RESULTS

Twenty-six pathologies were treated with EVT using a 3-Fr GS. Median radial artery diameter was 1.9 mm, and distal TRA (73.1%) was selected more often than TRA (26.9%) as the access site. The breakdown of target pathologies and the role of the 3-Fr GS were as follows: 12 unruptured cerebral aneurysms for intra-aneurysmal coiling, with 5 dural arteriovenous fistulas, 5 brain or head and neck tumors, 2 chronic subdural hematoma, 1 arteriovenous malformation, and 1 hereditary hemorrhagic telangiectasia for transarterial embolization. A success rate of 96.2% was achieved, with no access site- or non-access site-related complications observed within 30 days.

CONCLUSION

The straight-shaped 3-Fr GS may be applicable for selected pathologies, allowing access even with RAs <2 mm in diameter and facilitating EVT without complications. Preliminary experience with the 3-Fr GS via TRA demonstrated excellent feasibility and safety.

Distal radial approach for arterial pressure monitoring with a long catheter provides safe and stable monitoring in the intensive care unit: A single-center retrospective study

BACKGROUND

To compare the distal radial artery approach (DRA) with a longer catheter to DRA with a shorter catheter in arterial catheter (AC) placement in the intensive care unit (ICU).

METHODS

This was a single-center retrospective cohort study of DRA with a long catheter (60 mm) for arterial catheterization in the ICU. DRA with a short catheter (25-30 mm) was used in the control group, and the groups were compared using multivariate regression analysis. The primary study endpoint was the incidence of unplanned AC removal. The secondary endpoint was the incidence of other inappropriate events, namely loss of arterial pressure waveforms, bleeding, catheter-related infection, pressure ulcer, and other complications associated with the AC.

RESULTS

In this study, the DRA with a long catheter was used in 50 patients. No unplanned AC removals or other inappropriate events occurred, and there were no complications associated with the DRA. The DRA procedural success rate was 100%. There was no significant difference in hemostasis times between the groups. Loss of arterial waveforms was an early predictor of unplanned AC removal.

CONCLUSIONS

The DRA with a long catheter provided stable monitoring and was associated with a low unplanned removal rate. This method has the advantages of fewer complications and shorter hemostasis time compared with the DRA with a short catheter, and may become a new AC option in the ICU.

Transradial Stent Angioplasty Using Double Guide Wires for Severe Stenosis of Vertebral Artery Ostium at a Lower Location

OBJECTIVE

To investigate the effect and safety of transradial stent angioplasty using double guide wires for severe stenosis of vertebral artery ostium at a lower location.

METHODS

Patients with severe stenosis of the vertebral artery ostium at a lower location treated with transradial stent angioplasty were retrospectively enrolled. All the clinical and endovascular treatment data were analyzed.

RESULTS

Thirty-nine patients were enrolled. A low location of the vertebral artery ostium was present in 33 (84.6%) patients and an ultra-low location in 6 (15.4%). Transradial stent angioplasty was performed in all patients. In one patient who had a tortuous radial artery, the transradial access was failed. In the other 38 (97.4%) patients, transradial stent angioplasty was all successful. The sharp angle formed between the vertebral artery and the subclavian artery was significantly (P < 0.0001) increased from 15° to 65° (36° ± 11°) before to 70-125° (90° ± 17°) after insertion of a support guide wire. No damage was found in all support guide wires. Thirty-nine stents were deployed, and the preoperative stenosis rate of 70%-98% (85% ± 13%) was significantly (P < 0.0001) decreased to 0-25% (16%) immediately after stenting. Six-12 months after surgery, 29 (74.4% or 29/39) patients were followed up with imaging, and 9 (31.0%) patients experienced in-stent restenosis, with endovascular retreatment being performed in 3 (33.3%) patients.

CONCLUSIONS

Transradial stent angioplasty using double guide wires is safe and effective for the treatment of severe stenosis of the vertebral artery ostium at a lower location even though more studies are necessary to confirm this.

Comparison of ultrasound features and lesion sites in dysfunctional arteriovenous fistula

This study aimed to investigate ultrasound features of arteriovenous fistula stenosis and their relationship with primary patency after percutaneous transluminal angioplasty (post-intervention primary patency) and compare this classification with that using lesion location. Hemodialysis patients who underwent ultrasound-guided percutaneous transluminal angioplasty for arteriovenous fistula stenosis from July 2020 to December 2021 were retrospectively evaluated. Lesions (excluding inflow arteries) were categorized into five groups based on ultrasound features, and the clinical characteristics and risk factors affecting the post-intervention primary patency of the arteriovenous fistula were analyzed. Among 185 patients, 100 (54.05%), 36 (19.46%), 22 (11.89%), 11 (5.95%), and 16 (8.65%) were classified into the intima-dominant, non-intima-dominant, valve obstruction, vascular calcification, and mixed groups, respectively. The dialysis duration and arteriovenous fistula use time were the highest in the vascular calcification group at 86 (interquartile range: 49-140) and 77 (interquartile range: 49-110) months, respectively. Diabetes mellitus was most common in the intima-dominant group (42.0%). In Kaplan-Meier and univariate Cox analysis, type III lesion location (stenosis in the venous confluence site) was associated with the lower post-intervention primary patency. In the multivariate Cox analysis, percutaneous transluminal angioplasty times (the number of times patients were treated with percutaneous transluminal angioplasty for arteriovenous fistula stenosis dysfunction), vascular calcification, calcification at the lesion site requiring percutaneous transluminal angioplasty, and serum parathyroid hormone levels were independent risk factors for post-intervention primary patency. Ultrasound features showed that calcification of the arteriovenous fistula was detrimental to the post-intervention primary patency of arteriovenous fistula.

Risk factors for puncture-related complications after cerebrovascular angiography and neuroendovascular intervention with distal transradial approach

BACKGROUND AND PURPOSE

To determine the risk factors for puncture-related complications after the distal transradial approach (dTRA) for cerebrovascular angiography and neuroendovascular intervention and to explore the incidence and potential mechanisms of procedural failure and puncture-related complications.

MATERIALS AND METHODS

From February to November 2023, 62 patients underwent dTRA in our department. Demographic, clinical, and procedural data were collected retrospectively. Postoperative puncture-related complications were defined as a syndrome of major hematoma, minor hematoma, arterial spasm/occlusion, arteriovenous fistula, pseudoaneurysm, and neuropathy. Univariate and multivariate logistic regressions were performed to identify significant factors contributing to puncture-related complications.

RESULTS

Forty-five diagnostic cerebral angiograms and 17 neurointerventions were performed or attempted with dTRA in 62 patients. Procedural success was achieved via dTRA in 47 (75.8%) patients, whereas 15 (24.2%) required conversion to other approaches. Reasons for failure included puncture failure (n = 8), inability to cannulate due to arterial spasm (n = 6), and inadequate catheter support of the left vertebral artery (n = 1). 17.0% (8/47) of patients had postoperative puncture-related complications. Minor hematoma occurred in 8.5% (4/47) of patients, arterial spasm/occlusion in 6.3% (3/47), and neuropathy in 2.1% (1/47). No major complications were observed. On stepwise multivariable regression analysis, BMI (OR = 0.70, 95%CI 0.513 to 0.958; p = 0.026) was an independent risk factor for puncture-related complications, with a cut-off of 24.8 kg/m2 (sensitivity 66.7% and specificity 87.5%).

CONCLUSION

Our cohort is the first study of risk factors for puncture-related complications after neurointerventional interventions with dTRA. This study has shown that a low BMI (< 24.8 kg/m2) is independently associated with the development of puncture-related complications.

Pseudoaneurysm Following a Puncture of the Distal Radial Artery: A Case Report

Pseudoaneurysms are not uncommon in the clinic, but they have rarely been reported as a result of distal radial artery puncture. This case report is about an elderly woman who developed a pseudoaneurysm at the distal radial artery puncture site after coronary angiography via the distal radial artery. After timely treatment and long-term follow-up, the patient's hand wound gradually healed.

A Radial Approach Combined With a Contralateral Vertebral Retrograde Approach for Stenting and Coil Embolization of a Large Posterior Inferior Cerebellar Artery Aneurysm

BACKGROUND

Wide-neck aneurysm embolism is a technically demanding procedure. Stent device deployment is challenging intraoperatively, especially in parent arteries with acute angles.

CASE DESCRIPTION

The authors describe the case of a 74-year female with an unruptured right posterior inferior cerebellar artery aneurysm. The acute angle of the arteries proximal to the posterior inferior cerebellar artery complicated the condition, and the distal end of the guidewire failed to enter the posterior inferior cerebellar artery despite several maneuvers. The wide neck of the aneurysm was located in the posterior inferior cerebellar artery, so a stent was needed. The stent was deployed from the left vertebral artery retrograde to the right vertebral artery.

CONCLUSIONS

The authors report the successful application of a rare strategy, the radial approach combined with a contralateral vertebral retrograde approach, for stent deployment.

Vertebral Artery Access Considerations in Coil Embolization of Small Superior Cerebellar Artery Aneurysm

BACKGROUND

Coiling of small superior cerebellar artery aneurysms (sSCAAs) is challenging. We aimed to describe anatomic considerations in the vertebral and basilar artery (VA and BA) morphology for decision making in the coiling of sSCAAs.

METHODS

Eleven patients with sSCAAs (<5 mm) treated at our institution between April 2015 and February 2022 were included to show our concept of deciding access routes in the coiling of sSCAAs. The access route was decided on the basis of VA characteristics, BA curvature, and aneurysm laterality. Adequate aneurysm occlusion on angiography (Raymond-Roy grading scale I and II), good outcome (modified Rankin Score 0-2) at the last follow-up, and adverse outcomes were evaluated.

RESULTS

Simple coiling (n = 2), a balloon-assisted technique (n = 3), and stent-assisted technique (n = 6) were selected. At the last follow-up (median 13.0 months), adequate aneurysm occlusion and good outcome were obtained in all 9 patients (n = 10). Adverse outcomes were not observed. When VA dominance was equal, in the straight BA, the microcatheter insertion into the ipsilateral VA to the aneurysm was favorable to form a "fulcrum" on the contralateral side and obtain microcatheter stability. When an aneurysm was on the concave aspect of the curved BA, microcatheter insertion into the ipsilateral VA was favorable. As for the convex aspect's aneurysm location, the microcatheter insertion into the contralateral VA can be favored. Further, we described the VA origin classification as it relates to ease of access from a transradial approach.

CONCLUSIONS

Vertebrobasilar morphology may be important in deciding access routes in the coiling of sSCAAs.

Trans-Distal Radial Artery Carotid Revascularization with Forearm Flow Reversal: An Alternative Option of CAS in the TCAR Era

BACKGROUND

Transcarotid artery revascularization (TCAR) has emerged as an alternative to carotid artery stenting (CAS). TCAR demonstrated its superiority by avoiding femoral artery puncture and establishing proximal protection without crossing the stenotic lesion. In the TCAR era, we focused on the possibility of a trans-distal radial approach (DRA). A balloon-guide catheter was navigated via DRA to establish proximal protection before lesion crossing. The forearm subcutaneous vein was used as the flow-reversal circuit.

METHODS

Six internal carotid artery stenosis patients underwent CAS using "the forearm flow reversal technique." Every procedure was performed under continuous flow reversal from the common carotid artery to the forearm cephalic vein.

RESULTS

Successful revascularization was achieved without ischemic or access-site complications. The distal radial artery was patent at discharge in all cases.

CONCLUSIONS

Trans-distal radial CAS with forearm flow reversal is a feasible and less invasive technical option.

How to Omit the Potential Pitfalls in Distal Radial Access: Lessons From Cadaveric and CTA Analysis

OBJECTIVES

To verify the anatomical basis, ideal puncture sites, and potential pitfalls of the distal radial artery (dRA) in the anatomical snuffbox region for distal radial access (dTRA).

MATERIALS AND METHODS

Overall, 26 formalin-fixed upper limbs and computed tomography angiography (CTA) of the upper limbs of 168 consecutive patients were studied. Cadaveric dissection and dRA 3D reconstruction were used to evaluate the dRA route for dTRA. The puncture sites, dRA diameter, and angle of the dRA and tendons of the extensor pollicis brevis were also measured in the patients and cadavers.

RESULTS

The cadaver dissection provided more insights than did the dRA 3D reconstruction. However, preoperative evaluation had better diagnostic accuracy (p=0.024). Puncture sites 1 and 3 had a high success rate (63.2% possible success rate, 191/302). The DISFAVOR theory was put forward, in which 8 types of potential pitfalls that may interrupt puncture procedure or lead to a surgical failure were observed, including occlusion, stenosis, tortuosity, arteriovenous fistula, angioma, different radial artery (RA) ramifications, radial veins, and cephalic veins. The mean diameter of dRA based on cadaver dissection and CTA was 2.53 (SD=0.73) and 2.63 (SD=0.69) mm, respectively. Furthermore, the minimum distance from the outer layer of dRA to the skin was 5.71 (SD=2.0) mm based on CTA. The angle between the dRA and tendons of extensor pollicis brevis (TEPB) based on cadaver dissection and CTA was 58.0° (SD=21.5°) and 51.8° (SD=16.6°), respectively.

CONCLUSIONS

Puncture sites 1 and 3 were more suitable for the dTRA, and we put forward the DISFAVOR theory to summarize the 8 types of potential pitfalls during the use of dTRA.

Transradial or Transulnar Long Sheath Access to the Brachial Artery Allows for Neuroendovascular Procedures in Patients with Radial or Ulnar Artery Occlusion

BACKGROUND

Transradial access is an important tool for many neuroendovascular procedures. Occlusion of the radial or ulnar artery is not uncommon after transradial or transulnar access and can present a challenge for patients requiring repeat angiography.

METHODS

Between March 2022 and June 2023, patients undergoing transradial or transulnar angiography who were found to have a radial artery occlusion or ulnar artery occlusion were identified. Repeat catheterization of the occluded artery was attempted using a 21-gauge single wall puncture needle and a 0.021-inch wire to traverse the occlusion and insert a 23-cm sheath into the brachial artery.

RESULTS

A total of 25 patients undergoing 26 angiograms during the study period were found to have a radial artery occlusion or ulnar artery occlusion. Successful repeat catheterization of the occluded artery was achieved in 21 of 26 cases (80.7%). Outer diameter sheath size ranged from 5 Fr (0.0655 inch) to 8 Fr (0.1048 inch). No access complications were encountered. Number of prior angiograms, time since prior angiogram, and prior angiogram procedure time were associated with lower likelihood of successful access.

CONCLUSIONS

Transradial or transulnar neuroangiography through an occluded radial or ulnar artery is safe and feasible by traversing the occlusion into the brachial artery with a 23-cm sheath. Repeat catheterization is most successful in patients with an arterial occlusion <6 months old. This technique is important in patients who have limited options for arterial access, avoiding access site complications inherent in transfemoral access, and in patients who specifically require radial or ulnar artery access.

Distal radial access for neuroangiography and neurointerventions: systematic review and meta-analysis

BACKGROUND

Many studies have shown that coronary angiography (CAG) and percutaneous coronary intervention (PCI) via distal radial access (DRA) are safe and effective. Safety and efficacy of neuroangiography and neurointerventions via DRA are unknown.

PURPOSE

Search the literatures on neuroangiography and neurointerventions via DRA and conduct a systematic review and meta-analysis.

METHODS

PubMed, Embase and Cochrane were searched from inception to November 10, 2022. After literature screening, data extraction and assessment of literature quality, random effects model was used for meta-analysis.

RESULTS

A total of 236 literatures were retrieved, and 17 literatures including 1163 patients were finally included for meta-analysis.The pooled access success rate was 0.96 (95% confidence interval, 0.94-0.98), and the heterogeneity was obvious (I2 = 55.5%). The pooled access-related complications incidence rate was 0.03 (95% confidence interval, 0.02-0.05), and the heterogeneity was not obvious (I2 = 15.8%).

CONCLUSION

Neuroangiography and neurointerventions via DRA may be safe and effective. DRA is an alternative access for neuroangiography and neurointerventions.

Distal versus conventional transradial access for diagnostic cerebral angiography and neurointerventional procedures: A systematic review and meta-analysis

BACKGROUND

Distal transradial artery access (dTRA) has received increasing consideration for performing diagnostic cerebral angiography and neurointerventional procedures. In this meta-analysis, we aim to evaluate the safety and efficacy of dTRA compared to conventional transradial access (cTRA) for cerebral angiography and neurointerventions.

METHOD

A systematic review and meta-analysis were conducted on studies investigating outcomes of dTRA and cTRA in neurointerventions. The primary outcome was technical success rates. Secondary outcomes included access site complication rates, crossover rates to alternative vessels, fluoroscopy time, and contrast volume. The random effects model was used to calculate the mean difference (MD) and odds ratios (OR) with 95% confidence intervals (Cl).

RESULTS

Eight retrospective observational studies with a total of 1477 patients who underwent 1175 diagnostic cerebral angiography and 516 neurointerventional procedures using 546 dTRA and 1164 cTRA approaches were included in our meta-analysis. The technical success rate was similar between dTRA and cTRA groups (95.8% vs 91.4%; OR:1.65; 95% Cl: 0.52 to 5.22; P = 0.40). Similarly, no difference was seen in dTRA and cTRA regarding access site complications (2% vs 1.4%; OR: 1.31; 95% CI: 0.47 to 3.61; P = 0.61) and access site crossover (2.1% vs 5.3%; OR: 0.55; 95% Cl: 0.28 to 1.05; P = 0.07). After resolving heterogeneity among included studies, dTRA was associated with a shorter fluoroscopy time (MD: -0.91 min; 95% CI: -1.74 to -0.09; P = 0.03) and lower contrast volume (MD: -8.32 mL; 95% CI = -14.7 to -1.94; P = 0.011).

CONCLUSION

Our findings suggest that the dTRA approach is a safe and effective alternative to the cTRA approach in patients undergoing cerebral angiography and neurointerventions.

Transradial versus transfemoral access for posterior circulation endovascular intervention: A systematic review and meta-analysis

OBJECTIVE

Transradial access (TRA) provides a more direct entry to posterior circulation system for endovascular therapy compared to transfemoral access (TFA). This meta-analysis aims to evaluate the safety and feasibility of TRA in neurointervention of posterior circulation.

MATERIALS AND METHODS

A systematic search was conducted in the Wanfang Data, CBM, PubMed, Embase, Cochrane Library, Web of Science databases. The primary outcomes included total complications and access site complications. Secondary outcomes were single puncture success, procedural success, access cross-over, catheter retention time and fluoroscopy time.

RESULTS

Six studies encompassing 297 patients were included in the meta-analysis. Compared to the TFA group, the TRA group showed significantly decreased total complications (odds ratio [OR] = 0.29, 95% confidence interval [CI] [0.12, 0.73], p < 0.01) and access site complications (OR = 0.19, 95%CI [0.06, 0.62], p < 0.01), yet it had a longer catheter retention time (mean difference [MD] = 0.80, 95%CI [0.60, 1.00], p < 0.01). There were no significant differences in single puncture success (OR = 3.68, 95%CI[0.38, 35.86], p = 0.26), procedural success (OR = 0.30，95%CI [0.05, 1.73], p = 0.18), access cross-over (OR = 2.29, 95%CI [0.19, 28.26], p = 0.52), fluoroscopy time (MD = 0.97, 95%CI [- 0.91, 2.84], p = 0.31) between the TRA and TFA groups.

CONCLUSION

This meta-analysis demonstrated that TRA is a safe and feasible alternative to TFA for neurointervention in the posterior circulation. TRA showed significantly decreased total complications and access site complications, yet it had a longer catheter retention time than TFA.

Analysis of treatment cost differences in patients undergoing femoral versus radial access in outpatient diagnostic cerebral arteriograms

BACKGROUND

Outpatient diagnostic cerebral arteriograms are the most common procedure in neuroendovascular surgery, and the use of transradial access for these studies is growing. Although transradial access has been associated with lower hospital costs for elective diagnostic and interventional neuroendovascular procedures, no study has compared transfemoral access and transradial access costs for a homogenous population of patients undergoing outpatient diagnostic cerebral arteriogram.

METHODS

In this single-center retrospective study, the Value Driven Outcomes database was used to evaluate treatment costs for patients who underwent outpatient diagnostic cerebral arteriogram from January 2019 to December 2022. Propensity-score matching was performed to reduce confounders. Costs from each encounter were subcategorized into imaging, supplies, pharmacy, procedures, labs, and facility costs.

RESULTS

After matching, 337 patients each for transradial access and transfemoral access were available for analysis. A total of 118,992 cost data points were associated with all encounters. Overall, per-visit costs were 15.2% cheaper for patients who underwent transradial access versus transfemoral access (p < 0.001). Most of the cost difference was due to supplies (35.2% cost difference, p < 0.001) and procedure costs (9.3% cost difference, p < 0.001). No statistical differences were observed between the two approaches in imaging, pharmacy, labs, and facility costs (all p > 0.05).

CONCLUSIONS

Costs for outpatient diagnostic cerebral arteriogram were lower in patients who underwent transradial access versus transfemoral access because of supply and procedure costs. Understanding reasons for cost differences in common procedures is important for creating strategies to reduce overall healthcare costs. Additionally, addressing the cost differences of newer techniques may increase the likelihood that they are more readily implemented by hospitals and providers.

Therapeutic efficacy and complications of radial versus femoral access in endovascular treatment of unruptured intracranial aneurysms

PURPOSE

The transradial approach (TRA) in neuroendovascular treatment is known to have a lower risk of complications than the transfemoral approach (TFA). However, little research has focused on assessments of efficacy and risk of complications in the treatment of intracranial aneurysms. This study aimed to compare the efficacy and complications of TRA and TFA in coil embolization of unruptured intracranial aneurysms (UIAs) at our institution.

METHODS

Consecutive patients who underwent endovascular surgery via TRA or TFA at a single institution from 1 April 2019, to 28 February 2022, were retrospectively analyzed. Patients were classified into TRA and TFA groups and assessed using propensity-adjusted analysis for outcomes including fluoroscopy time, volume embolization ratio (VER), and complications.

RESULTS

A total of 163 consecutive UIAs were treated with coil embolization during the 35-months study period. The incidence of minor access site complications (ASCs) was significantly higher with TFA (20%, 25/126) than with TRA (2.7%, 1/37; p = 0.01). Propensity-adjusted analysis (matched for age, sex, aneurysm volume, embolization technique, and sheath size) revealed that TRA was associated with a lower risk of minor ASCs (odds ratio, 0.085; 95% confidence interval 0.0094-0.78; p = 0.029). However, TRA did not differ significantly from TFA with respect to fluoroscopy time, VER, major ASCs, and non-ASCs.

CONCLUSIONS

Coil embolization for UIAs via TRA can reduce risk of minor ASCs without increasing the risk of non-ASCs compared with conventional TFA, and can achieve comparable results in term of efficacy and fluoroscopy time.

Transradial Access Failures During Neuroangiography for Patients With Moyamoya

BACKGROUND

Despite studies continuing to demonstrate the utility of transradial access (TRA) in neuroangiography, minimal data exist regarding predictors of TRA failure. Furthermore, although many patients with moyamoya disease/syndrome will require life-long angiographic evaluation, even less has been reported on the usage of TRA in this population.

OBJECTIVE

To perform a matched analysis at our high-volume moyamoya center to determine predictors of TRA failure in these patients.

METHODS

A total of 636 patients undergoing TRA for neuroangiography were identified from 2018 to 2020. Demographic and angiographic characteristics including radial artery spasm (RAS), radial anomalies, and access site conversion were compared between patients with moyamoya and the rest of the cohort. A 4:1 matched analysis, based on age and sex, was also performed to eliminate confounding variables.

RESULTS

Patients with moyamoya were younger (40 vs 57 years, P < .0001), had smaller radial diameters (1.9 vs 2.6 mm, P < .0001), more commonly had a high brachial bifurcation (25.9% vs 8.5%, P = .008), more frequently experienced clinically significant RAS (40% vs 8.4%, P < .0001), and more often required access site conversion (26.7% vs 7.8%, P = .002). Increasing age was associated with less TRA failures in patients with moyamoya (odds ratio = 0.918) but more failures in the rest of the cohort (odds ratio = 1.034). In the matched analysis, patients with moyamoya continued to experience more radial anomalies, RAS, and access site conversions.

CONCLUSION

Patients with moyamoya, when controlling for age and sex, have higher rates of TRA failure during neuroangiography. Increasing age in Moyamoya is inversely correlated with TRA failures suggesting that younger patients with moyamoya are at higher risk of extracranial arteriopathy.

Risk factors for radial artery occlusion after neurointervention for unruptured intracranial aneurysm via transradial access

PURPOSE

Neurointervention via transradial access (TRA) is less invasive than via transfemoral access. However, radial artery occlusion (RAO) may occur with TRA. The purpose of this study was to explore risk factors for RAO after coil embolization of unruptured intracranial aneurysms (UIAs) via TRA.

METHODS

Forty-two consecutive patients who underwent coil embolization for UIAs via TRA between March 2021 and March 2022 and were available for angiographic evaluation 1 year after treatment were retrospectively reviewed. Multivariate logistic regression analysis was conducted to identify potential risk factors for RAO.

RESULTS

Seventeen (40%) of the 42 patients showed RAO. Compared with the non-RAO group, radial artery size was significantly smaller (2.2 mm [interquartile range (IQR): 2.1, 2.4 mm] vs 2.6 mm [IQR: 2.5, 2.7 mm]; p = 0.001) and the incidence of radial artery spasm (RAS) was significantly higher in the RAO group. Multivariate analysis identified radial artery size (odds ratio [OR] 4.9 × 10^-3, 95% confidence interval [CI] 6.4 × 10^-5-0.38) and incidence of RAS (OR 14.8, 95%CI 2.1-105) as significant independent predictors of subsequent RAO. Based on receiver operating characteristic (ROC) curve analysis, the optimal cutoff for radial artery size was 2.5 mm (sensitivity, 82.4%; specificity, 76.0%; area under the ROC curve, 0.80 [95%CI 0.66-0.95]).

CONCLUSION

Radial artery size and RAS represent reliable parameters for predicting RAO 1 year after coil embolization for UIA via TRA. Prophylaxis against RAS and limiting neurointervention via TRA to patients with radial artery larger than 2.5 mm in diameter may reduce the risk of postoperative RAO.

A novel technique to perform cerebral angiography via the left radial approach: An 80 patients series

PURPOSE

To demonstrate that left radial access for diagnostic cerebral angiography with Extra backup and 4F vertebral catheters is feasible and safe.

MATERIALS AND METHODS

This study is a retrospective review of our prospective database on left radial access for cerebral angiography procedures, using an extra backup catheter associated with a 4Fr vertebral catheter, performed between March and September 2019. Patient demographics, procedural and radiographic metrics as well as clinical data were recorded.

RESULTS

Seventy five patients with mean age of 51...years (range 21...73) underwent 80 cerebral angiographies. An average of four vessels were catheterized and mean fluoroscopy times per subject and vessel were was of 13.9 and 3.3...min, respectively. One patient required crossover to transfemoral access because of radial artery spasm. There were one asymptomatic distal radial artery occlusion and one patient presenting with asymptomatic skin blanching area on the forearm, just proximal to the tip of the sheath, that spontaneously resolved within an hour.

CONCLUSION

Diagnostic cerebral angiography via left radial access is feasible and safe and allows to preserve the right radial access for future neurointerventions while providing more comfort to the right handed patient.

The anatomical snuffbox for transradial access in arteriovenous fistula intervention: Case report and brief review of the literature

Left distal transradial artery (dTRA) access in the anatomical snuffbox is a relatively novel technique and is considered beneficial when left TRA access is required. This technique offers essential advantages, including improved patient comfort and lower vascular complications. dTRA may provide an entry site for retrograde recanalization of the radial artery. We presented a case of a 65-year-old man with 5-stage chronic kidney disease (CKD) and had left a radio-cephalic arteriovenous fistula (AVF) for routine hemodialysis. There was obstruction of AVF a month after creation. The vascular intervention has been performed using left dTRA access for retrograde recanalization. Angiogram showed cephalic vein obstruction and non-significant stenosis of the proximal radial artery. Percutaneous transluminal angioplasty was successful in improving cephalic vein flow. Hemostatic performed without a hemostatic device. This case report highlights the dTRA access approach in the anatomical snuffbox to recanalize AVF occlusion in the wrist in a patient with CKD.

Transradial access with intra-aortic catheter looping for the treatment of intracranial aneurysms

Purpose

The study aimed to investigate the feasibility and effect of transradial access with intra-aortic catheter looping for the treatment of intracranial aneurysms.

Materials and methods

This retrospective one-center study was performed on patients with intracranial aneurysms which were embolized through transradial access with intra-aortic catheter looping because of the difficulty of transfemoral access or transradial access without intra-aortic catheter looping. The imaging and clinical data were analyzed.

Results

A total of 11 patients were enrolled, including seven (63.6%) male patients. Most patients were associated with one or two risk factors of atherosclerosis. There were nine aneurysms in the left internal carotid artery system and two aneurysms in the right internal carotid artery system. All 11 patients had complications with different anatomic variations or vascular diseases, which made endovascular operation via the transfemoral artery difficult or a failure. The right transradial artery approach was adopted in all patients, and the success rate of intra-aortic catheter looping was 100%. Embolization of intracranial aneurysms was successfully completed in all patients. No instability of the guide catheter was encountered. No puncture site complications or surgical-related neurological complications occurred.

Conclusion

Transradial access with intra-aortic catheter looping for embolization of intracranial aneurysms is technically feasible, safe, and efficient as an important supplementary approach to the routine transfemoral access or transradial access without intra-aortic catheter looping.

Transradial approach in neurointervention: Part-I: Patient selection, preparation, and access site considerations

Transradial access (TRA) is gradually getting attention in neurointervention radiology. Neurointerventionists now understand its advantages such as lesser complications, short hospital stay, and better patient satisfaction than transfemoral access. This review aims to provide a comprehensive approach for the interventionist to get familiar with the TRA. In this first part of the review, we will focus on patient selection, preparation, and access-related issues of a standard TRA.

Use of reverse angle guide catheter with trans-radial approach in patients undergoing middle meningeal artery embolization

Background

Trans-radial access (TRA) for MMA embolization has grown due to lower access site complications and greater patient satisfaction. Here, we describe the feasibility of utilizing a 6F Envoy Simmons 2 (6F-SIM2) as a guide catheter with TRA and compare outcomes with trans-femoral approach (TFA) in a single center case series.

Methods

We performed a retrospective review of patients who underwent MMA embolization for management of chronic subdural hematoma (cSDH). TRA was performed by utilizing a combination of 6F 90cm Envoy (Codman &amp; Shurtleff, Inc., Rayham, MA) Simmons 2 guide catheter and 5F 125cm Sofia (Microvention, Aliso Viejo, CA) intermediate catheter. Outcomes measured are Modified Rankin Score (mRS) at 90 days, inpatient mortality, post-embolization recurrence, fluoroscopy time and radiation exposure.

Results

A total of 71 patients underwent 97 MMA embolization overall with 65 (67%) in trans-femoral access group, 11 (11.3%) in trans-radial access without use of Simmons 2 Guide catheter group and 21 (21.6%) in trans-radial access with use of Simmons 2 Guide catheter group. There were no direct access-related complications in either group. One patient had thromboembolic stroke in trans-femoral group. There was no difference in average procedure-related total fluro time or radiation dose among all three groups.

Conclusion

Trans-radial approach using 6F-SIM2 guide catheter coupled with 5F Sofia intermediate catheter is safe and effective. It provides an alternative approach to access distal branches of bilateral anterior circulation in elderly patients with difficult anatomy undergoing MMA embolization.

Bilateral Distal Transradial Approach for Coiling of Basilar Artery Aneurysm: A Technical Note

Distal transradial approach (dTRA) for neuroendovascular procedures has received much attention in recent years as a newer and less invasive alternative to the conventional transfemoral or transradial approaches. We present the case of an 89-year-old woman with a basilar artery aneurysm requiring simultaneous catheterization of the bilateral vertebral arteries who was successfully embolized using bilateral dTRA. The aneurysm was accessed from the right vertebral artery using the right dTRA. Control angiograms during the procedure were performed from the left vertebral artery via the left dTRA. The operator's posture was ergonomically comfortable, and the catheters were easy to handle during the procedure. To the best of our knowledge, this is the first case of a bilateral dTRA used for neuroendovascular procedures. Bilateral dTRA is a safe and minimally invasive method for patients and ergonomically comfortable for operators.

Transradial versus Transfemoral Approaches in Diagnostic and Therapeutic Neuroendovascular Interventions: A Meta-Analysis of Current Literature

BACKGROUND

The adoption of the transradial approach (TRA) has been increasing in popularity as a primary method to conduct both diagnostic and therapeutic interventions. As this technique gains broader acceptance and use within the neuroendovascular community, comparing its complication profile with a better-established alternative technique, the transfemoral approach (TFA), becomes more important. This study aimed to evaluate the safety of TRA compared with TFA in patients undergoing diagnostic, therapeutic, and combined neuroendovascular procedures.

METHODS

A systematic review and meta-analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A literature search of PubMed and other databases was conducted for studies from all available dates. To compare TRA and TFA, we performed an indirect meta-analysis between studies that mentioned the complications of the procedures.

RESULTS

Our search yielded 532 studies, of which 108 met full inclusion criteria. A total of 54,083 patients (9137 undergoing TRA and 44,946 undergoing TFA) were included. Access site complication rate was lower in TRA (1.62%) compared with TFA (3.31%) (P < 0.01). Neurological complication rate was lower in TRA (1.64%) compared with TFA (3.82%) (P = 0.02 and P < 0.01, respectively). Vascular spasm rate was higher in TRA (3.65%) compared with TFA (0.88%) (P < 0.01). Wound infection complication rate was higher in TRA (0.32%) compared with TFA (0.2%) (P < 0.01).

CONCLUSIONS

Patients undergoing TFA are significantly more likely to experience access site complications and neurological complications compared with patients undergoing TRA. Patients undergoing TRA are more likely to experience complications such as wound infections and vascular spasm.

Distal radial artery access in noncoronary procedures

Since the beginning of interventional cardiology and for decades, the femoral artery has been the access of choice for both diagnostic and interventional endovascular procedures. Due to an extensive evidence base accumulated over the last 20 years, the majority of interventional cardiologists around the world prefer classical radial artery access for both elective and emergency procedures. A similar trend has been observed for distal radial artery access over the last five years. Noncoronary endovascular surgery undergoes the same stages of improvement and optimization of access, but in a more accelerated way. The goal of this review is to analyze the literature on distal radial artery access in noncoronary procedures.

Initial Experience Using the Transradial Approach for Endovascular Treatment of Vascular Pathologies: Safety and Feasibility

Background  Endovascular treatment of vascular pathologies through the transradial approach has been increasingly used and has demonstrated a low rate of complications.

Objective  To report our initial experience in the endovascular treatment of cerebrovascular diseases with the transradial approach and to determine its safety and feasibility.

Methods  Consecutive patients who underwent the transradial approach for endovascular treatment of aneurysms and vascular malformations were reviewed at a single institution. Technical success, fluoroscopy time, and access-related complications were analyzed.

Results  Eight patients underwent endovascular treatment with the transradial approach. One arteriovenous fistula, one superficial temporal artery aneurysm, three arteriovenous malformations, and four aneurysms were treated successfully. The radial artery was successfully approached and a 6-F sheath was used in all the cases. Navigation of guiding catheters (5 and 6 F) was done without complications. The most commonly approached artery was the right internal carotid artery, followed by the right vertebral artery. Postoperative vasospasm was identified in three patients. Mean fluoroscopy time was 34.7 minutes. Conversion to transfemoral approach was not required. No postoperative complications were reported.

Conclusions  In our initial experience, the transradial approach is a safe and feasible alternative for the endovascular treatment of cerebrovascular pathologies.

Safety and Effectiveness of Coronary Angiography or Intervention through the Distal Radial Access: A Meta-Analysis

Objectives

Searching the literature for coronary angiography (CAG) or intervention through distal radial access (DRA) and performing a meta-analysis.

Background

Coronary angiography (CAG) or intervention through distal radial access (DRA) may have a similar success rate, low radial artery occlusion rate, low radial artery spasm rate, and low rate of puncture site hematoma for patients with coronary heart disease. Therefore, the randomized controlled trials (RCTs) were searched, and the data were pooled for meta-analysis to evaluate the effectiveness and safety of DRA.

Methods

RCTs comparing the CAG or intervention through DRA vs. transradial access (TRA) published between January 1, 2017, and May 4, 2021, were searched in the PubMed, Embase, and Cochrane databases. The endpoints included the rate of access success and the number of radial artery occlusions, radial artery spasms, and puncture site hematomas. The data were extracted, and a random-effects model was used for analysis.

Results

Among 204 studies, 6 RCTs (with 2825 participants) met the inclusion criteria. Compared to TRA, the access success rate in DRA (p=0.1) and the lower rate of puncture site hematoma were not significantly different (p=0.646), while the radial artery occlusion rate (p < 0.001) and radial artery spasm rate (p=0.029) were significantly lower.

Conclusion

In summary, DRA has a similar access success rate and incidence of hematoma at the puncture site, but a lower incidence of RAO and spasm compared to TRA. These findings demonstrated that DRA is a safe and effective access for CAG or intervention.

Transradial versus transfemoral access for acute stroke endovascular thrombectomy: a 4-year experience in a high-volume center

PURPOSE

To compare clinical outcomes and safety of transradial (TRA) versus transfemoral access (TFA) for endovascular mechanical thrombectomy in acute stroke patients.

METHODS

Retrospective analysis of 832 consecutive patients with acute stroke undergoing interventional thrombectomy using TRA (n = 64) or TFA (n = 768).

RESULTS

Direct TFA failures occurred in 36 patients, 18 of which underwent crossover TFA to TRA, while direct TRA failures occurred in 2 patients having both crossovers to TFA. Successful catheterization was achieved in 96.8% (62/64) and 95.3% (732/768) of patients undergoing direct TRA and direct TFA, respectively, without significant differences. The median (IQR) catheterization time was 10 (8-16) min in the direct TRA group and 15 (10-20) in the direct TFA group (P < 0.001). This difference was also significant in the subgroup of anterior circulation strokes and in patients younger and older than 80 years of age. The majority of procedures yielded thrombolysis in cerebral infarction grade 2b/2c/3 revascularization in patients undergoing direct TRA (88.5%) and direct TFA (90.8%), without statistically significant differences. The median (IQR) puncture to recanalization time was 37 (24-58) min for the direct TRA group and 42 (28-70) min for the direct TFA group. Significant differences in access site complications, symptomatic ICH, and mRS score 0-2 at 90 days between both TRA and TFA accesses were not found.

CONCLUSIONS

TRA is not inferior to TFA in the probability of catheterization, times of catheterization and revascularization, and other clinical outcomes for mechanical thrombectomy in acute stroke.

Comparison of the Safety, Efficacy, and Procedural Characteristics Associated with Proximal and Distal Radial Access for Diagnostic Cerebral Angiography

OBJECTIVES

Radial access is an increasingly popular approach for performing cerebral angiography. There are two sites for radial artery puncture: proximal transradial access (pTRA) in the wrist and distal transradial access (dTRA) in the snuffbox. These approaches have not been directly compared.

MATERIALS AND METHODS

Consecutive diagnostic cerebral angiograms performed at a single institution were retrospectively reviewed. Outcomes included fluoroscopy time, radiation dose, contrast volume, time to obtain access, procedure duration, and time to discharge home. Success rates as well as minor and major complication rates associated with each approach were also compared. Multivariate linear regression models were used to determine the relationship between access site and outcomes while adjusting for covariates.

RESULTS

A total of 287 angiograms on 244 patients met the inclusion criteria. pTRA was associated with shorter fluoroscopy time (ß -2.54, 95% CI -4.18 - -0.9, p = 0.003) and lower radiation dose (ß -242.89, 95% CI -351.55 - -134.24, p < 0.001), but not contrast volume. Time to obtain access, procedure duration, and time to discharge home were similar between approaches. A total of 10 minor complications occurred with similar rates for each approach (8 for dTRA, 2 for pTRA, p = 0.168) and there were no major complications. The conversion rate to femoral access was low (1.05% overall) and did not differ with approach.

CONCLUSION

dTRA and pTRA are associated with similarly high rates of safety and efficacy. Procedure duration, time to obtain access, and time to discharge did not differ between approaches.

Distal transradial artery access for coronary angiography in a patient having rheumatoid arthritis-related severe arthropathies

Conventional radial access has become the default access for coronary angiography. Sometime, it is difficult to take a conventional radial access, especially in patients having severe arthropathies leading to limited wrist joint mobility. In such scenarios, distal transradial access (dTRA) can be adopted. We describe a case of an elderly male patient having rheumatoid arthritis with arthropathies. He presented to us with unstable angina; coronary angiogram was advised for ischaemia assessment. Right dTRA was adopted due to severe joint deformity at wrist joint, limiting joint extension. A successful coronary angiogram was performed via the right dTRA without major discomfort and complications. Haemostasis was secured with TR band radial artery compression device. In this case report, we have evaluated the importance of practising dTRA in a patient with severe arthropathies.

Initial experience of subcutaneous nitroglycerin for distal transradial access in neurointerventions

BACKGROUND

Transradial access (TRA) for diagnostic and interventional neuroendovascular procedures has gained significant popularity in recent years due to its improved safety profile and appeal to patients compared with transfemoral access. However, risks of TRA include hand ischemia in cases of poor ulnar collateral circulation and inability to cannulate the radial artery due to its relatively small diameter. By accessing the radial artery distal to the superficial palmar arch where ulnar collateral blood flow arises, in the anatomic snuffbox, the risk of hand ischemia is theoretically eliminated. The use of subcutaneous nitroglycerin and lidocaine to improve rates of success in radial artery access has been reported in the cardiac literature, however, has yet to be described for neurointerventional procedures. We discuss our technique and report our initial experience using subcutaneous nitroglycerin and lidocaine cocktail for access to the distal transradial artery in a variety of neuroendovascular procedures.

METHODS

A retrospective review of our institution's database of neurointerventional and diagnostic procedures performed using dTRA was conducted, and 64 patients were identified between February and December 2020. Patient demographics, clinical data, procedural details, and radiographic information were collected and analyzed.

RESULTS

A total of 64 patients underwent neurointerventional procedures using the subcutaneous injection for dTRA access. The procedures performed included diagnostic cerebral angiograms (n = 47), stent and balloon assisted aneurysm coiling (n = 5), flow diversion (n = 2), intra-saccular device placement (n = 1), mechanical thrombectomy (n = 1), tumor embolization (n = 1), middle meningeal artery embolization (n = 2), extracranial carotid stent placement (n = 2), and arteriovenous malformation embolization (n = 3). While no complications of hand ischemia were appreciated, the access site conversion rate was 3.1%; 2 cases required a switch to femoral artery access due to proximal vessel tortuosity and aortic anatomical variations, and not due to access site complication. Furthermore, on repeat angiograms by the same proceduralist, distal TRA (dTRA) was successful in 100% of the cases.

CONCLUSION

dTRA using subcutaneous nitroglycerin and lidocaine is a safe and effective method for neurointerventional and diagnostic procedures.

Radial artery access anatomy: considerations for neuroendovascular procedures

Although enthusiasm for transradial access for neurointerventional procedures has grown, a unique set of considerations bear emphasis to preserve safety and minimize complications. In the first part of this review series, we will review important anatomical considerations for safe and easy neuroendovascular procedures from a transradial approach. These include normal and variant radial artery anatomy, the anatomic snuffbox, as well as axillary, brachial, and great vessel arterial anatomy that is imperative for the neuroendovascular surgeon to be intimately familiar prior to pursuing transradial access procedures. In the next part of the review series, we will focus on safety and complications specific to a transradial approach.

Safety of ultrasound-guided distal radial artery access for abdominopelvic transarterial interventions: a prospective study

PURPOSE

We aimed to evaluate ultrasound-guided distal radial artery (DRA) access to perform abdominopelvic endovascular procedures.

METHODS

A prospective, observational study was carried out in a single center between December 2017 and February 2019. Forty-two abdominopelvic endovascular procedures were performed by the same operator in 37 patients with DRA access using a 5 F sheath. Most patients were male (67.6%) with a mean age of 62.0±11.4 years (age range, 27.6-82.8 years). Patient characteristics, including Barbeau's test classification, radial and ulnar sizes and technical success, were evaluated. Patients with a DRA smaller than 1.7 mm could not be safely punctured and were not included.

RESULTS

Procedures included chemoembolization of hepatocellular carcinoma in 35 cases (83.3%), embolization of hepatic metastasis in neuroendocrine tumors in 4 cases (9.5%) and other embolization procedures in 3 cases (7.1%). The mean diameters of the DRA, proximal radial artery and proximal ulnar artery were 2.31, 2.63, and 2.09 mm, respectively. Out of 42 DRA puncture attempts, 97.6% (41/42) were successfully performed. There were no postoperative complications related to the access site, such as pain, palsy, paresthesia, occlusion, finger ischemia, bleeding, hematoma, and pseudoaneurysm. Transient forearm discomfort was reported in 7.1% of patients (3/42); one occurrence was associated with kinking rectification, and two occurrences were attributed to small arteries and/or vasospasm.

CONCLUSION

Ultrasound-guided DRA access seems to be feasible and safe to perform in abdominopelvic endovascular procedures in patients with a DRA considered amenable to be safely punctured, with high technical success rates.

Distal radial artery approach for endovascular therapy

It has been reported that the distal transradial approach (dTRA) is safe and useful for percutaneous coronary intervention (PCI). In this study we evaluated the safety and efficacy of the dTRA for endovascular therapy (EVT). The dTRA for EVT was performed in 43 lesions from 35 patients. Approach site was determined at the discretion of the operator. Clinical data were analyzed retrospectively. Average patient age was 74.0 ± 6.5 years; 30 (86%) were male; average height was 161.1 ± 8.4 cm. Diabetes mellitus, hypertension, dyslipidemia, and smoking habit were present in 19 (54.3%), 31 (88.6%), 29 (82.9%), and 29 (82.9%) patients, respectively. Target lesions were iliac artery in 38 (88.4%) patients, superficial femoral artery in 4 (9.3%) and renal artery in the remaining patient (2.3%). Eight lesions (18.6%) were chronic total occlusions. Thirteen (30.2%), 2 (4.7%), and 28 (65.1%) lesions were treated using 4.5, 6, and 7 French long guiding systems, respectively. All lesions were successfully treated without any procedural or access site-related complications. No additional puncture sites were required. Ankle brachial index significantly improved from 0.62 ± 0.20 to 0.92 ± 0.17 (p < 0.0001) post-treatment for the lower limbs. There were no radial artery occlusions, target lesion revascularization, or complications 1 month later. Similar to PCI, the dTRA for EVT is safe and feasible without any specific complications in carefully selected patients.

The Rist radial access system: a multicenter study of 152 patients

BACKGROUND

Transradial access (TRA) for neurointervention is becoming increasingly popular as experience with the technique grows. Despite reasonable efficacy using femoral catheters off-label, conversion to femoral access occurs in approximately 8.6-10.3% of TRA cases, due to an inability of the catheter to track into the vessel of interest, lack of support, or radial artery spasm.

METHODS

This is a multicenter, retrospective case series of patients undergoing neurointerventions using the Rist Radial Access System. We also present our institutional protocol for using the system.

RESULTS

152 patients were included in the cohort. The most common procedure was flow diversion (28.3%). The smallest radial diameter utilized was 1.9 mm, and 44.1% were performed without an intermediate catheter. A majority of cases (96.1%) were completed successfully; 3 (1.9%) required conversion to a different radial catheter, 2 (1.3%) required conversion to femoral access, and 1 (0.7%) was aborted. There was 1 (0.7%) minor access site complication and 4 (2.6%) neurological complications.

CONCLUSIONS

The Rist catheter is a safe and effective tool for a wide range of complex neurointerventions, with lower conversion rates than classically reported.

Lessons Learned After 760 Neurointerventions via the Upper Extremity Vasculature: Pearls and Pitfalls

BACKGROUND

The radial approach has been gaining more widespread use by neurointerventionalists fueled by data from the cardiology literature showing better safety and overall reduced morbidity.

OBJECTIVE

To present our institution's experience with the radial approach for neuroendovascular interventions in 614 consecutive patients who underwent a cumulative of 760 procedures.

METHODS

A retrospective analysis was performed and identified neuroendovascular procedures performed via the upper extremity vasculature access site.

RESULTS

Amongst 760 procedures, 34.2% (260) were therapeutic, and 65.7% (500) were nontherapeutic angiograms. Access sites were 71.5% (544) via a conventional radial artery, 27.8% (211) via a distal radial artery, 0.5% (4) via an ulnar artery, and 0.1% (1) via the brachial artery. Most of the procedures (96.9%) were performed via the right-sided (737), 2.9% (22) via the left-sided, and 0.1% (1) via a bilateral approach. Major access site complications occurred at a rate of 0.9% (7). The rate of transfemoral conversion was 4.7% (36). There was a statistically higher incidence of transfemoral conversion when repeat procedures were performed using the same access site. Also, there was no significant difference between nontherapeutic procedures performed using the right and left radial access, and conventional versus distal radial access. Procedural metrics improved after completion of 14 procedures, indicating a learning curve that should be surpassed by operators to reach optimal outcomes.

CONCLUSION

Radial artery catheterization is a safe and effective means of carrying out a wide range of neuroendovascular procedures associated with excellent clinical outcomes and an overall low rate of periprocedural complications.

Distal Transradial Artery Access for Neuroangiography and Neurointerventions : Pitfalls and Exploring the Boundaries

Introduction

The distal transradial approach (dTRA) is progressively gaining more clinical use in the fields of cardiology and other vascular interventions, as it offers a number of advantages compared to conventional radial approach (TRA). These include lower rates of vascular occlusion which permits preservation of the proximal radial artery for future procedures in the event of a distal occlusion.

Aim

To share the experience in the use of dTRA for neurointerventions, showing its advantages, pitfalls as well as sharing our optimized puncture and hemostatic ultrarapid compression protocols to improve the use of this vascular access.

Methods

A retrospective analysis of our experience of diagnostic and interventional procedures performed via dTRA using an optimized protocol for puncture and postpuncture compression of the dTRA was performed.

The rate of complications (hematoma and arterial dissection at puncture site) femoral crossover, and assessment of postprocedural stenosis/occlusion with the ultrarapid compression protocol were also assessed.

Results

From March 2019 to July 2020 a total of 100 distal radial procedures were carried out and 53 diagnostic angiograms (53%) and 47 interventional procedures (47%) were included in the analysis. We achieved a 96% technical success, with a femoral crossover requirement in 3 cases (3%), and one conventional TRA crossover due to puncture failure.

Of the patients 3 presented puncture site hematomas (3%) with no intervention required, 61 patients (61%) underwent the ultrarapid hemostasis protocol in association with a hemostatic pad. Ultrasound follow-up was performed in 20 patients (20%) at 1–2 months with 1 case of occlusion (5%) and 2 of radial stenosis (10%). In all 3 cases proximal radial artery remained patent.

Conclusion

The dTRA is a safe and feasible access route for angiography and neurointerventions. Using vasodilators prepuncture, we attained a variable increase in the vascular diameter facilitating puncture and reducing the risk of occlusion and vascular spasm.

A rapid deflation protocol for postpuncture hemostasis does not significantly increase the hematoma rate.

Comparison of Transradial vs Transfemoral Access in Neurovascular Fellowship Training: Overcoming the Learning Curve

BACKGROUND

The transradial access (TRA) is rapidly gaining popularity for neuroendovascular procedures as there is strong evidence for its benefits compared to the traditional transfemoral access (TFA). However, the transition to TRA bears some challenges including optimization of the interventional suite set-up and workflow as well as its impact on fellowship training.

OBJECTIVE

To compare the learning curves of TFA and TRA for diagnostic cerebral angiograms in neuroendovascular fellowship training.

METHODS

We prospectively collected diagnostic angiogram procedural data on the performance of 2 neuroendovascular fellows with no prior endovascular experience who trained at our institution from July 2018 until June 2019. Metrics for operator proficiency were minutes of fluoroscopy time, procedure time, and volume of contrast used.

RESULTS

A total of 293 diagnostic angiograms were included in the analysis. Of those, 57.7% were TRA and 42.3% were TFA. The median contrast dose was 60 cc, and the median radiation dose was 14 000 μGy. The overall complication rate was 1.4% consisting of 2 groin hematomas, 1 wrist hematoma, and 1 access-site infection using TFA. The crossover rate to TFA was 2.1%. Proficiency was achieved after 60 femoral and 95 radial cases based on fluoroscopy time, 52 femoral and 77 radial cases based on procedure time, and 53 femoral and 64 radial cases based on contrast volume.

CONCLUSION

Our study demonstrates that the use of TRA can be safely incorporated into neuroendovascular training without causing an increase in complications or significantly prolonging procedure time or contrast use.

Radial Artery Access for Cerebral Angiography: 2-Dimensional Operative Video

A number of studies have demonstrated that the radial artery is a safer access site than the femoral artery for endovascular procedures.1-4 In the prospective randomized studies comparing transradial and transfemoral approaches for cardiac procedures, there was a 60% reduction in access site complications as well as significant decreases in all-cause mortality with the transradial approach as compared to transfemoral, which has led to the adoption of a radial first strategy.5-7 Neurointerventional studies have demonstrated similar safety benefits as well as improved patient preference.8-14 In this video, a patient presented with an unruptured anterior communicating artery aneurysm and consented to a transradial artery diagnostic cerebral angiogram. This technical video demonstrates the key preprocedural preparation, room setup, patient positioning, steps for radial artery, and distal radial artery puncture and sheath placement. Distal transradial artery access is our preferred approach for diagnostic cerebral angiography because of an improved safety profile and procedural ergonomics. In cases in which a larger radial artery is advantageous such as for neurointerventions requiring larger systems, a standard transradial approach may be performed.9 In this video, a full 6-vessel cerebral angiogram is performed, followed by our arteriotomy closure technique using our standard equipment including a 10-cm 5 French Glidesheath Slender (Terumo, Japan), 100-cm hydrophilic coated 5 French Simmons 1 catheter (Merit OEM), 0.035 hydrophilic coated guidewire, and SafeGuard closure device (Merit, Salt Lake City, Utah).

Transition from Proximal to Distal Radial Access for Diagnostic Cerebral Angiography: Learning Curve Analysis

BACKGROUND

Distal transradial access (dTRA) has several advantages compared with proximal transradial access (pTRA) for cerebral angiography. The learning curve for transitioning from pTRA to dTRA has not been described.

METHODS

Retrospective analysis of the first 75 diagnostic cerebral angiograms performed with dTRA by a single operator was performed. Outcomes included time for sheath insertion, sheath to first vessel time, procedure duration, fluoroscopy time, radiation dose, and contrast volume. Their associations with procedure number were evaluated with multivariate linear regressions, segmented linear regression, and locally weighted regression (LOESS).

RESULTS

The mean age of patients was 56.1 years and 61.3% were female. Seventy-four of 75 angiograms were successfully completed with dTRA. There were 3 minor and no major complications. After adjusting for covariates, sheath to first vessel time (β = -0.50, P < 0.001) and procedure duration (β = -0.26, P = 0.002) were associated with procedure number. Time for sheath insertion, fluoroscopy time, radiation dose, and contrast volume were not associated with procedure number. Segmented linear regression identified break-points of 33 for sheath to first vessel time and 11 for procedure duration, which corresponded to the procedure number after which these outcomes trended down. LOESS models for time to sheath placement, procedure duration, fluoroscopy time, and radiation dose predicted minimum values between procedures 40-50.

CONCLUSIONS

Transitioning from pTRA to dTRA for diagnostic cerebral angiography is feasible and safe. The learning curve is overcome between procedures 11 and 33, and further refinement in performance occurs through procedures 40-50.

Learning curves for transradial access versus transfemoral access in diagnostic cerebral angiography: a case series

BACKGROUND

The perception of a steep learning curve associated with transradial access has resulted in its limited adoption in neurointervention despite the demonstrated benefits, including decreased access-site complications.

OBJECTIVE

To compare learning curves of transradial versus transfemoral diagnostic cerebral angiograms obtained by five neurovascular fellows as primary operator.

METHODS

The first 100-150 consecutive transradial and transfemoral angiographic scans performed by each fellow between July 2017 and March 2020 were identified. Mean fluoroscopy time per artery injected (angiographic efficiency) was calculated as a marker of technical proficiency and compared for every 25 consecutive procedures performed (eg, 1-25, 26-50, 51-75).

RESULTS

We identified 1242 diagnostic angiograms, 607 transradial and 635 transfemoral. The radial cohort was older (64.3 years vs 62.3 years, p=0.01) and demonstrated better angiographic efficiency (3.4 min/vessel vs 3.7 min/vessel, p=0.03). For three fellows without previous endovascular experience, proficiency was obtained between 25 and 50 transfemoral angiograms. One fellow achieved proficiency after performing 25-50 transradial angiograms; and the two other fellows, in <25 transradial angiograms. The two fellows with previous experience had flattened learning curves for both access types. Two patients experienced transient neurologic symptoms postprocedure. Transradial angiograms were associated with significantly fewer access-site complications (3/607, 0.5% vs 22/635, 3.5%, p<0.01). Radial-to-femoral conversion occurred in 1.2% (7/607); femoral-to-radial conversion occurred in 0.3% (2/635). Over time, the proportion of transradial angiographic procedures increased.

CONCLUSION

Technical proficiency improved significantly over time for both access types, typically requiring between 25 and 50 diagnostic angiograms to achieve asymptomatic improvement in efficiency. Reduced access-site complications and decreased fluoroscopy time were benefits associated with transradial angiography.