Transradial versus transfemoral approaches for diagnostic cerebral angiography: a prospective, single-center, non-inferiority comparative effectiveness study

Comparative Analysis of Transpedal and Transfemoral Access During Genicular Artery Embolization for Knee Osteoarthritis

PURPOSE

This retrospective study aimed to compare the efficacy and safety of transpedal access (TPA) with transfemoral access (TFA) in Genicular Artery Embolization (GAE).

MATERIALS AND METHODS

60 patients who underwent GAE between January and June 2023, were recruited and outcomes were compared between the TFA (n = 37) and TPA (n = 23) groups. Technical and clinical success rates, complications, and patient-reported outcomes were assessed.

RESULTS

All patients attained a 100% technical success rate, which was defined as the successful selective catheterization and embolization of at least one feeding artery to the knee joint, without encountering any major complications. Minor complications, observed in 12/60 patients (20%), were predominantly manifested as a transient skin discoloration. The TPA group had a comparatively higher (p = 0.008) rate of minor complication than the TFA group. Notably, TPA was associated with a longer duration of the procedure (p = 0.013), duration of fluoroscopy (p = 0.004), increased total air kerma (p = 0.037), dose-area product values (p = 0.021), and a greater incidence of vasospasm (p = 0.018) than TFA. However, TPA patients reported shorter recovery times and less post-procedural discomfort, especially reduced back pain due to postinterventional bedrest (p < 0.001). At the 3-month follow-up, the clinical success rate was similar between the two groups (p = 0.905).

CONCLUSION

TFA is the safer and faster method for GAE, offering fewer complications and reduced radiation exposure. For patients with challenging groin anatomies, however, TPA may provide a valuable alternative.

Applied anatomy of the vertebral arteries for endovascular neurointerventions

The vertebral arteries (VAs) constitute most of the arterial supply to the posterior cerebral vascular circulation. They have anatomical specificities and may have variants that are critical for neurointerventionists to recognize in order to design open or endovascular surgical treatment. This review addresses each segment of the VA including its origin and discusses the branches and relevant anatomical features for neurointerventions.

Radial Versus Femoral Access for Mechanical Thrombectomy in Patients With Stroke: A Noninferiority Randomized Clinical Trial

BACKGROUND

Transfemoral access is predominantly used for mechanical thrombectomy in patients with stroke with a large vessel occlusion. Following the interventional cardiology guidelines, routine transradial access has been proposed as an alternative, although its safety and efficacy remain controversial. We aim to explore the noninferiority of radial access in terms of final recanalization.

METHODS

The study was an investigator-initiated, single-center, evaluator-blinded, noninferiority randomized clinical trial. Patients with stroke undergoing mechanical thrombectomy, with a patent femoral artery and a radial artery diameter ≥2.5 mm, were randomly assigned (1:1) to either transradial (60 patients) or transfemoral access (60 patients). The primary binary outcome was the successful recanalization (expanded Treatment in Cerebral Ischemia score, 2b-3) assigned by blinded evaluators. We established a noninferiority margin of -13.2%, considering an acceptable reduction of 15% in the expected recanalization rates.

RESULTS

From September 2021 to July 2023, 120 patients were randomly assigned and 116 (58 transradial access and 58 transfemoral access) with confirmed intracranial occlusion on the initial angiogram were included in the intention-to-treat analysis. Successful recanalization was achieved in 51 (87.9%) patients assigned to transfemoral access and in 56/58 (96.6%) patients assigned to transradial (adjusted 1 side risk difference [RD], -5.0% [95% CI, -6.61% to +13.1%]) showing noninferiority of transradial access. Median time from angiosuite arrival to first pass (femoral, 30 [interquartile range, 25-37] minutes versus radial: 41 [interquartile range, 33-62] minutes; P<0.001) and from angiosuite arrival to recanalization (femoral: 42 (IQR, 28-74) versus radial: 59.5 (IQR, 44-81) minutes; P<0.050) were longer in the transradial access group. Both groups presented 1 severe access complication and there was no difference in the rate of access conversion: transradial 7 (12.1%) versus transfemoral 5 (8.6%) (P=0.751).

CONCLUSIONS

Among patients who underwent mechanical thrombectomy, transradial access was noninferior to transfemoral access in terms of final recanalization. Procedural delays may favor transfemoral access as the default first-line approach.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT05225636.

Transradial access for the endovascular treatment of intracranial aneurysms using the Woven EndoBridge device: A systematic review and pooled analysis

BACKGROUND

The Woven EndoBridge (WEB) device is a minimally invasive endovascular treatment option for patients with cerebral aneurysms. Transradial access (TRA) is a technique that involves accessing the arterial system through the radial artery in the wrist rather than the femoral artery in the groin. Several studies have investigated the use of TRA for WEB device deployment in treating intracranial aneurysms.

METHODS

A systematic review was conducted to evaluate the TRA for WEB device deployment in treating intracranial aneurysms. The databases PubMed, Cochrane, Embase, Scopus, and Web of Science were searched. To reduce the risk of bias, this systematic review only included studies reporting on using TRA in WEB device deployment for intracranial aneurysm treatment with a minimum of four patients.

RESULTS

In this systematic review, 186 patients were included across five studies, with TRA used in 183 cases analyzed. The study population had a higher proportion of females (n = 118%-69%) than males, with a mean age of 62 years old. Among the aneurysms treated, 46 were ruptured, and 119 were located at bifurcation sites, with a mean maximum diameter/width of 6.6 mm and mean height of 5.9 mm. Adjunctive coiling was used in three cases, and adjunctive stenting was used in nine cases. In two cases, conversion to a femoral artery access was necessary.

CONCLUSION

The available results suggest TRA with the WEB device is a safe and effective alternative. However, using TRA versus TFA should be individualized based on patient factors and operator experience.

Transradial versus transfemoral access for diagnostic cerebral angiography: frequency of acute MRI findings in 500 consecutive patients at a single center

BACKGROUND

The frequency of clinically symptomatic and asymptomatic diffusion-weighted imaging (DWI) hyperintense lesions and their correlation with the transradial artery (TRA) approach is unclear.

OBJECTIVE

To assess the frequency of abnormal diffusion restriction foci on DWI following cerebral angiography (digital subtraction angiography (DSA)) with the TRA or transfemoral artery (TFA) approach and identify predictors of DWI restriction foci.

METHODS

We analysed data from consecutive diagnostic cerebral angiograms obtained between January 2021 and October 2023 at a single tertiary center. MRI DWI was performed 2 hours after DSA. Patients underwent neurological assessment periprocedurally, as well as prior to discharge.

RESULTS

500 patients were analysed; 277 (55%) procedures were performed via TRA and 223 (45%) via TFA. Overall, 74 (14.8%) patients had abnormal findings in the postprocedure MRI DWI. A higher incidence of positive DWI findings was noted in the TRA group, with 46 (16.6%) patients, compared with 28 (12.6%) in the TFA group (P=0.21). Symptomatic events occurred in seven (2.5%) of the TRA group and in two (0.9%) of the TFA cohort (P=0.31). At 60 days, the neurological deficit rate was one (0.4%) for the TRA group and one (0.4%) for the TFA group. Procedure time was the only significant predictor of DWI restriction (OR=1.04 per minute; P=0.0001).

CONCLUSION

Although there were more symptomatic or asymptomatic embolic events with TRA than with the TFA approach following elective cerebral angiography, this was not significantly different. We recommend the choice of vascular access based on patient anatomy and characteristics, aimed at improving care through enhanced safety.

Systematic Review and Meta-analysis of Radial or Femoral Access for Carotid Stenting

PURPOSE

There is a growing interest in performing coronary artery and neurovascular interventions via the radial artery; however, few studies have examined the outcomes of transradial carotid stenting. Therefore, our study aimed to compare cerebrovascular outcomes and crossover rates in carotid stenting between transradial and traditional transfemoral approaches.

METHODS

A systematic review was performed by searching three electronic databases from inception to June 2022 in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. In addition, random effect meta-analysis was used to pool the odds ratios (ORs) for stroke, transient ischemic attack, major adverse cardiac events, death, major vascular access site complications, and procedure crossover rates between the transradial and transfemoral approaches.

RESULTS

A total of 6 studies were included involving a total of n = 567 transradial and n = 6176 transfemoral procedures. The ORs for stroke, transient ischemic attack, and major adverse cardiac events were 1.43 (95% confidence interval, CI 0.72-2.86, I2 = 0), 0.51 (95% CI 0.17-1.54, I2 = 0), and 1.08 (95% CI 0.62-1.86, I2 = 0), respectively. Neither the major vascular access site complication rate (OR 1.11, 95% CI 0.32-3.87, I2 = 0) nor crossover rate (OR 3.94, 95% CI 0.62-25.11, I2 = 57%) showed statistically significant differences between the two approaches.

CONCLUSION

The modest quality of the data suggested comparable procedural outcomes between the transradial and transfemoral approaches when performing carotid stenting; however, high level evidence regarding postoperative brain images and risk of stroke in transradial carotid stenting are lacking. Therefore, it is reasonable for interventionists to weigh up the risks of neurological events and potential benefits, including fewer access site complications, before choosing the radial or femoral arteries as access sites. Future large-scale randomized controlled trials are imperative.

Comparison between transradial and transfemoral mechanical thrombectomy for ICA and M1 occlusions: insights from the Stroke Thrombectomy and Aneurysm Registry (STAR)

BACKGROUND

The role for the transradial approach for mechanical thrombectomy is controversial. We sought to compare transradial and transfemoral mechanical thrombectomy in a large multicenter database of acute ischemic stroke.

METHODS

The prospectively maintained Stroke Thrombectomy and Aneurysm Registry (STAR) was reviewed for patients who underwent mechanical thrombectomy for an internal carotid artery (ICA) or middle cerebral artery M1 occlusion. Multivariate regression analyses were performed to assess outcomes including reperfusion time, symptomatic intracerebral hemorrhage (ICH), distal embolization, and functional outcomes.

RESULTS

A total of 2258 cases, 1976 via the transfemoral approach and 282 via the transradial approach, were included. Radial access was associated with shorter reperfusion time (34.1 min vs 43.6 min, P=0.001) with similar rates of Thrombolysis in Cerebral Infarction (TICI) 2B or greater reperfusion (87.9% vs 88.1%, P=0.246). Patients treated via a transradial approach were more likely to achieve at least TICI 2C (59.6% vs 54.7%, P=0.001) and TICI 3 reperfusion (50.0% vs 46.2%, P=0.001), and had shorter lengths of stay (mean 9.2 days vs 10.2, P<0.001). Patients treated transradially had a lower rate of symptomatic ICH (8.0% vs 9.4%, P=0.047) but a higher rate of distal embolization (23.0% vs 7.1%, P<0.001). There were no significant differences in functional outcome at 90 days between the two groups.

CONCLUSIONS

Radial and femoral thrombectomy resulted in similar clinical outcomes. In multivariate analysis, the radial approach had improved revascularization rates, fewer cases of symptomatic ICH, and faster reperfusion times, but higher rates of distal emboli. Further studies on the optimal approach are necessary based on patient and disease characteristics.

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.

Transradial and transfemoral accesses for cerebral angiography: a retrospective comparative study

OBJECTIVE

Many large randomized trials in interventional cardiology have shown a significant advantage of transradial access (TRA) over transfemoral access (TFA). However, TRA has yet been widely used in Neurovascular interventional surgery. The purpose of this retrospective comparative study is to compare the effectiveness and safety of transradial and transfemoral accesses for cerebral angiography.

METHODS

A total of 380 patients underwent cerebral angiography in our center between January 2019 and January 2021. Among them, 192 patients underwent TRA, and 188 patients via TFA. The success rate of cerebral angiography, X-ray time, total absorbed dose, dose-area product (DAP), complications, and other clinical data were extracted.

RESULTS

The operative success (94.27% vs 97.87%; P = 0.071) and the puncture failure (1.56% vs 1.60%) were not significantly different between the TRA and TFA groups. Only arterial spasm, which is more common in the TRA group, was substantially different between the two groups in terms of surgical consequences (P = 0.015). In addition, there were no significant differences between the groups in total absorbed dose (P = 0.604) and DAP(P = 0.097). However, the X-ray time of the TRA group [281.50(216.30,342.00)] was shorter than the TFA group [296.50(230.80,363.50)] (P = 0.019).

CONCLUSIONS

TRA is effective and safe in cerebral angiography, and its use may be expanded.

Radial artery occlusion after aneurysm treatment using the rist guide catheter: Single center cohort study

BACKGROUND AND PURPOSE

Delayed radial artery occlusion (dRAO) is a frequent complication after transradial access (TRA) for neurointervention when using standard large guide catheters. The RIST 079 guide catheter (RIST GC) is the first catheter designed for TRA in neurointervention. We aimed to assess the rate of dRAO after intracranial aneurysm (IA) treatment using the RIST GC.

METHODS

Patients treated for an IA using TRA and the RIST GC between June 2021 and November 2022 were referred to a systematic US-doppler assessment of the radial artery patency at 3-month follow-up. Patients with and without dRAO were compared to identify risk factors.

RESULTS

Twenty-two patients were included in the analysis. At 3-months follow up, 6 patients (27.3 %) presented with dRAO. Four patients were asymptomatic and 2 experienced post-operative radial hematoma and wrist pain. There was a tendency towards younger age, longer procedure duration and higher rate of forearm hematoma in patients with dRAO. Navigation using the RIST GC was successful in 90.9 % of cases. Intracranial access failures and navigation complications were all related to left internal carotid artery navigation.

CONCLUSIONS

At 3-month follow up, 27.3 % of patients treated for IA using TRA with the RIST GC presented dRAO.

Transradial versus transfemoral approach in cerebral angiography: A meta-analysis

BACKGROUND

Cerebral angiography has two common access sites: Transradial approach and transfemoral approach. However, there's no definitive answer to which one is superior.

OBJECTIVE

Compare transradial approach and transfemoral approach for a cerebral angiography procedure.

METHODS

A systematic review of the literature of studies reporting both transradial approach and transfemoral approach results was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. PubMed, Cochrane Library, and Embase were queried.

RESULTS

The meta-analysis examined 18 studies comprising 9388 patients undergoing cerebral angiography. Among the patients, 4598 underwent transradial approach (48.9%) and 4790 underwent transfemoral approach (51.1%). Our results revealed no statistical differences between the approaches regarding procedure success, crossover to transfemoral approach, procedure and fluoroscopy time between both approaches in cerebral angiography. Total, major, and minor complications comparisons were more favorable to transradial approach for this procedure.

CONCLUSION

These findings suggest, despite the ultimate decision regarding the choice of access method might be influenced by the physician's experience and personal preference, the data distinctly lean toward transradial approach as the preferable option for cerebral angiography. The advantages of transradial approach, highlighted by its lower complication rates, especially major complications, suggest that its adoption could contribute to enhanced patient safety and procedural outcomes.

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.

Awake transradial middle meningeal artery embolization and twist drill craniostomy for chronic subdural hematomas in the elderly: case series and technical note

BACKGROUND

Due to prohibitive perioperative risk factors, optimal treatment for chronic subdural hematomas (cSDH) in the elderly remains unclear. Minimally invasive techniques are a viable option and include bedside subdural evacuation port system (SEPS), as well as prevention of recurrence with middle meningeal artery (MMA) embolization. We present a case series of elderly patients undergoing combined transradial MMA embolization and bed-side craniostomy as primary treatment for cSDH.

METHODS

Patients 70 years and older from 2019 to 2020 that underwent single setting, awake transradial MMA embolization with concurrent SEPS placement under local anesthesia were included. Those with prior treatments, interventions performed under general anesthesia, or with less than 60-day follow-up were excluded. Descriptive analyses of baseline characteristics, radiologic parameters, comorbidities, and outcome measures were completed.

RESULTS

Twenty elderly patients (mean age of 81.0 years) with multiple comorbidities underwent 28 MMA embolization+SEPS procedures as primary treatment for cSDH. Mean cSDH thickness was 1.8cm±0.6 cm with 7.3±3.9 mm midline shift. All patients tolerated the procedure well. 1/20 (5.0%) patients died within 30 days of the procedure. A majority of patients were discharged to home (12/20; 60.0%). There was an average of 3.6-month follow-up and one patient (5.0%) developed recurrence in the follow-up period requiring further intervention.

CONCLUSIONS

In select elderly patients with high perioperative risk factors, primary treatment of cSDH using awake transradial MMA embolization+SEPS placement is a minimally invasive, feasible, and safe option. Further comparative studies are warranted to evaluate efficacy of the treatment.

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 for neurointerventional procedures: A practical approach

INTRODUCTION

Transradial approach (TRA) is a new technique proposed for performing cerebral angiography and neuro-interventional procedures. In this article, we sought to provide a step-by-step guide for carrying out a diagnostic cerebral angiography using this approach and summarize our center's experience.

MATERIAL AND METHODS

Records of patients since January 2020 were investigated, and data on demographic indices, reports of the procedures, outcomes, and complications were extracted. Then, these data were used to develop a step-by-step instruction for TRA cerebral angiography.

RESULTS

Two hundred eighty-nine patients matched our eligibility criteria with a mean age of 50 years and a female-to-male ratio of 1.18. Overall, TRA was carried out successfully for 97.2% (281 patients). In case TRA failed, transfemoral approach was considered for the procedure. Three minor complications (two vasospasm and one small hematoma) and two major complications (one pseudoaneurysm of the radial artery and one radial artery avulsion) were observed.

CONCLUSION

This article covers challenges a neurointerventionalist may face during a diagnostic cerebral angiography using TRA. Furthermore, our findings indicated that cerebral angiography with TRA might be performed safely and with a great success rate.

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.

Early exploration of the economic impact of transradial access (TRA) versus transfemoral access (TFA) for neurovascular procedures in Spain

INTRODUCTION

Transfemoral access (TFA) is the primary access approach for neurointerventional procedures. Transradial access (TRA) is established in cardiology due to its lower complications, yet, it is at its early stages in neuroprocedures. This study performs an early exploration of the economic impact associated with the introduction of TRA in diagnostic and therapeutic neuroprocedures from the Spanish NHS perspective.

METHODS

An economic model was developed to estimate the cost and clinical implications of using TRA compared to TFA. Costs considered access-related, complications and recovery time costs obtained from local databases and experts' inputs. Clinical inputs were sourced from the literature. A panel of eight experts from different Spanish hospitals, validated or adjusted the values based on local experience. Hypothetical cohorts of 10,000 and 1000 patients were considered for diagnostic and therapeutic neuroprocedures respectively. Deterministic sensitivity analysis was performed.

RESULTS

TRA in diagnostic procedures was associated with lower costs with savings ranging between €486 and €157 depending on the TFA recovery time considered. TRA is estimated to lead to 158 fewer access-site complications. In therapeutic procedures, TRA resulted in 76.4 fewer complications and was estimated to be cost-neutral with an incremental cost of €21.56 per patient despite recovery times were not included for this group. Variation of the parameters in the sensitivity analysis did not change the direction of the results.

LIMITATIONS

Clinical data was obtained from literature validated by experts therefore results generalizability is limited. In therapeutic neuroprocedures, there is an experience imbalance between approaches and recovery times were not included hence the total impact is not fully captured.

CONCLUSIONS

The early economic model suggests that implementing TRA is associated with reduced costs and complications in diagnostic procedures. In therapeutic procedures, TRA lead to fewer complications and it is estimated to be cost-neutral, however its full potential still needs to be quantified.

Cost Comparison: Evaluating Transfemoral and Transradial Access for Diagnostic Cerebral Angiography

BACKGROUND

Modern medicine necessitates the delivery of increasingly complex health care while minimizing cost. Transradial access (TRA) for neuroendovascular procedures is becoming more common as accumulating data demonstrate fewer complications, improved patient satisfaction, and high rates of treatment success compared with the transfemoral access (TFA) approach; however, disparities in cost between these approaches remain unclear. We compared supply and equipment costs between TRA and TFA for diagnostic cerebral angiography and evaluate the specific items that account for these differences.

METHODS

We reviewed all adult patients who underwent diagnostic cerebral angiography from July 1, 2019 to December 31, 2019. Data related to patient demographics, vascular access site, catheters used, cost of catheters, arterial access sheath use, cost of sheaths, closure devices used, and cost of closure devices were collected.

RESULTS

The transradial approach resulted in higher price of radial access sheath; however, the overall cost of closure devices was much lower in TRA group than in the TFA cohort. There was no significant difference in the cost of catheters. Overall, the total supply costs for TRA cerebral angiography were significantly lower than those of TFA cerebral angiography. The relative materials cost difference of using TRA was 20.9%.

CONCLUSION

This study is the first itemized materials cost analysis of TRA versus TFA cerebral angiography. TRA necessitates the use of a more expensive access sheath device; however, this cost is offset by the increased cost of devices used for femoral arteriotomy closure. Overall, the supply and equipment costs were significantly lower for TRA than TFA.

Comparison of transradial and transfemoral access for the Woven EndoBridge embolization of intracranial aneurysms: A single-center experience

BACKGROUND

Transradial access has been adopted more commonly in the neuroendovascular field. However, the experience of using this access for the Woven EndoBridge embolization of intracranial aneurysms is still in the early stage.

OBJECTIVE

This study aimed to compare the outcomes between transradial access and transfemoral access for the Woven EndoBridge embolization of intracranial aneurysms.

METHODS

This is a retrospective analysis of consecutive intracranial aneurysms treated with Woven EndoBridge placement between May 2019 and August 2020 by the senior author at a high-volume center. The aneurysms of all sizes and locations treated with Woven EndoBridge placement with or without adjunctive stent or coiling were included. Patient demographics, aneurysm and treatment characteristics, procedural complications, and angiographic and functional outcomes were compared between two approaches.

RESULTS

This study included a total of 34 patients with intracranial aneurysms (median age 60 years, female-to-male ratio 2:1). Of these, the radial access was utilized in 20 (58.8%) patients, while the femoral access was used in 14 (41.2%) patients. A Woven EndoBridge device was successfully deployed in all cases, and none of the patients required a crossover to another access. There were no significant differences in baseline characteristics, procedure time and fluoroscopy time, outcomes, and complication rates between both groups.

CONCLUSION

Our report suggests the possible feasibility and safety of the transradial access for the Woven EndoBridge embolization of intracranial aneurysms. However, the results of this study are suggestive rather than conclusive, and there is still a need for future large prospective studies.

Transradial versus transfemoral access for embolization of intracranial aneurysms with the Woven EndoBridge device: a propensity score-matched study

OBJECTIVE

Transradial access (TRA) is commonly utilized in neurointerventional procedures. This study compared the technical and clinical outcomes of the use of TRA versus those of transfemoral access (TFA) for intracranial aneurysm embolization with the Woven EndoBridge (WEB) device.

METHODS

This is a secondary analysis of the Worldwide WEB Consortium, which comprises multicenter data related to adult patients with intracranial aneurysms who were managed with the WEB device. These aneurysms were categorized into two groups: those who were treated with TRA or TFA. Patient and aneurysm characteristics and technical and clinical outcomes were compared between groups. Propensity score matching (PSM) was used to match groups according to the following baseline characteristics: age, sex, subarachnoid hemorrhage, aneurysm location, bifurcation aneurysm, aneurysm with incorporated branch, neck width, aspect ratio, dome width, and elapsed time since the last follow-up imaging evaluation.

RESULTS

This study included 682 intracranial aneurysms (median [interquartile range] age 61.3 [53.0-68.0] years), of which 561 were treated with TFA and 121 with TRA. PSM resulted in 65 matched pairs. After PSM, both groups had similar characteristics, angiographic and functional outcomes, and rates of retreatment, thromboembolic and hemorrhagic complications, and death. TFA was associated with longer procedure length (median 96.5 minutes vs 72.0 minutes, p = 0.006) and fluoroscopy time (28.2 minutes vs 24.8 minutes, p = 0.037) as compared with TRA. On the other hand, deployment issues were more common in those treated with TRA, but none resulted in permanent complications.

CONCLUSIONS

TRA has comparable outcomes, with shorter procedure and fluoroscopy time, to TFA for aneurysm embolization with the WEB device.

Safety of Sheathless Transradial Balloon Guide Catheter Placement for Acute Stroke Thrombectomy

BACKGROUND

Transradial access has been described for mechanical thrombectomy in acute stroke, and proximal balloon occlusion has been shown to improve recanalization and outcomes. However, sheathed access requires a larger total catheter diameter at the access site. We aimed to characterize the safety of sheathless transradial balloon guide catheter use in acute stroke intervention.

METHODS

Consecutive patients who underwent sheathless right-sided transradial access for thrombectomy with a balloon guide catheter were identified in a prospectively collected dataset from 2019 to 2021. Demographics, procedure details, and short-term outcomes were collected and reported with descriptive statistics.

RESULTS

A total of 48 patients (20 women) with a mean age of 72.3 years were identified. Of patients, 56.3% had occlusions in the left-sided circulation; 35 (72.9%) had M1 occlusions, 7 (14.6%) had M2 occlusions, and 6 (12.5%) had internal carotid artery occlusions. Tissue plasminogen activator was administered to 16 (33.3%) patients. Five (10.4%) patients underwent intraprocedural carotid stenting. The cohort had successful reperfusion after a median of 1 (interquartile range: 1, 2) pass. Median time from access to recanalization was 31 (interquartile range: 25, 53) minutes. A postprocedural Thrombolysis In Cerebral Infarction score of ≥2b was achieved in 46 (95.8%) patients. Five patients had wrist access site hematomas. All hematomas resolved with warm compresses, and no further intervention was required.

CONCLUSIONS

Sheathless radial access using a balloon guide catheter may be safely performed for acute ischemic stroke with excellent radiographic outcomes. Further investigation is warranted to evaluate the comparative effectiveness of sheathless compared with sheathed transradial balloon guide access.

Transradial access for cerebral angiography and neurointerventional procedures: A meta-analysis and systematic review

PURPOSE

Transradial access (TRA) for diagnostic and interventional neurointerventional procedures has recently gained traction over transfemoral access (TFA) in the neurointerventional community. This meta-analysis aims to assess and summarize the utility of TRA in cerebral angiography and neurointerventional procedures.

METHODS

A systematic literature review was performed utilizing Pubmed, Embase, and Scopus databases. Using PRISMA guidelines, records were extracted with the following search terms: transradial approach, transradial access, radial access, cerebral angiogram, cerebral angiography, neurointervention, and neuroendovascular. The primary outcomes assessed were case success rate, complication rate, and crossover rate from TRA to TFA. Secondary analysis was performed on procedure time, fluoroscopy time, fluoroscopy time per vessel (diagnostic procedures only), contrast dose, radial artery diameter, distal radial artery diameter, and patient preference for TRA over TFA.

RESULTS

Sixty-two full-text articles were analyzed for this meta-analysis, representing 12,927 diagnostic and interventional TRA access patients. Our analysis revealed a combined diagnostic and interventional case success rate of 95.9% and complication rate of 3.5%, with crossover to TFA occurring in 4.9% of cases.

CONCLUSION

This meta-analysis demonstrates that TRA access for diagnostic angiography and neurointerventional procedures is a safe and effective approach, though determining a true complication rate is challenging as the definition of TRA complications has changed in various publications over time.

Combined Transradial and Upper Extremity Transvenous Accesses in the Treatment of Carotid-Cavernous Fistulae: Two Case Reports and a Literature Review

The expansion of indications for neurointerventional procedures, combined with the need to treat a diverse patient population, has driven a need for broader access options. Concurrent arterial and venous access is often necessary for the diagnosis and treatment of various neurovascular diseases. Although complication rates are low, life-threatening severe complications have been reported with these access methods. Moreover, venous access through traditional routes can be challenging in patients with large body habitus. There is a growing trend of utilizing radial artery access for neuroendovascular procedures due to the increased ease of access and similar efficacy. Nevertheless, the use of upper limb veins in neurointerventional procedures is still rare. Upper extremity transvenous access (UETV) has recently emerged as an alternative strategy for neurointerventionalists, but data are limited. This study reports two cases of successful combined upper extremity transvenous access (TVA) and transradial access (TRA) in the treatment of carotid artery-cavernous fistulae. Combined TRA and UETV is a feasible, promising access strategy for patients and may also confer the same safety and patient satisfaction outcomes that have been seen with TRA. Further studies are needed to elucidate the exact impact this strategy has on patient outcomes and satisfaction.

Subclavian artery stenting via bilateral radial artery access: Four case reports

BACKGROUND

Subclavian artery stenosis refers to the stenosis in the lumen caused by the presence of plaque or thrombus in the subclavian artery. It is a common problem in endovascular interventions. In fact, conventional subclavian artery stenting via the femoral artery approach is effective and safe. Nevertheless, because femoral artery puncture is not easy to stop bleeding, it requires longer femoral artery compression or more expensive hemostatic materials, such as staplers. Patients need to be catheterized and bedridden for a longer time, which may lead to many complications, such as pseudoaneurysm.

CASE SUMMARY

Herein, we reported a new interventional therapy of subclavian artery. From March 1, 2020 to August 31, 2021, we operated on four patients with subclavian artery stenting via bilateral radial artery access.

CONCLUSION

After reviewing four cases of successful placement of clavicular artery stents via bilateral radial arteries, we concluded that bilateral radial artery approach is feasible. Clavicular artery stenting is safe, effective, and timesaving. It is an excellent alternative to the traditional femoral artery procedure, with few complications and high comfort degree.

Transradial Cerebral Angiography: Is it Feasible and Safe for Children?

PURPOSE

To investigate the feasibility and safety of transradial cerebral angiography (TRCA) in comparison to transfemoral cerebral angiography (TFCA) in the pediatric population.

MATERIALS AND METHODS

We retrospectively reviewed pediatric patients who underwent TRCA between January 2019 and July 2020. Patients with TFCA experience were examined. Pre- and post-procedural Doppler ultrasonography was performed to evaluate TRCA complications. To evaluate differences in radiation exposure between TRCA and TFCA, we investigated the radiation dose, dose area product (DAP), fluoroscopy time, and examination time.

RESULTS

Thirty-five patients (mean age, 13.8 years; 22 male) underwent TRCA, with 18 (mean age, 13.0 years; 10 male) experiencing TFCA. TRCA was successful in all cases without technical failure. Radiation exposure including radiation dose and DAP were significantly higher in the TRCA group (474.1 mGy and 8299.6 μGy m²) compared with the TFCA group (347.8 mGy and 6342.0 μGy m²). Fluoroscopy time and total examination time were significantly longer (145.1% and 32.6%) in TRCA (15.2 and 38.6 min) group compared with the TFCA group (6.2 and 29.1 min). Among the 26 patients who underwent post-procedural Doppler ultrasonography, five (19.2%) had complications after TRCA. Two (7.7%) patients showed radial artery stenosis, two (7.7%) had hematoma at the puncture site, and one (3.8%) showed thrombotic occlusion.

CONCLUSION

Although TRCA is a technically feasible and safe method in pediatric patients, high radiation exposure to TFCA must be considered. Therefore, it should be considered as an alternative method in those with unfavorable clinical situations for performing TFCA.

LEVEL OF EVIDENCE

Level 4, Case Series.

Roadmap Guided Direct Percutaneous Vertebral Artery Puncture for Mechanical Thrombectomy of Acute Basilar Artery Occlusion: A Technical Case Report and Review of the Literature

Access techniques for mechanical thrombectomy normally include percutaneous puncture of the common femoral or, more recently, the radial artery. Although target vessel catheterization may frequently not be devoid of difficulties via both routes, the vast majority of mechanical thrombectomy (MT) cases can be successfully managed. However, in a significant minority of cases, a stable target vessel access cannot be reached resulting in futile recanalization procedures and detrimental outcomes for the patients. As such, in analogy to direct carotid puncture for anterior circulation MT, direct vertebral artery (VA) puncture (DVP) is a direct cervical approach, which can constitute the only feasible access to the posterior circulation in highly selected cases. So far, due to the rarity of DVP, only anecdotal evidence from isolated case reports is available and this approach raises concerns with regard to safety issues, feasibility, and technical realization. We present a case in which bail-out access to the posterior circulation was successfully obtained through a roadmap-guided lateral direct puncture of the V2 segment of the cervical VA and give an overview of technical nuances of published DVP approaches for posterior circulation MT.

Comparison of radiation exposure and clinical outcomes between transradial and transfemoral diagnostic cerebral approaches: a retrospective study

OBJECTIVE

To identify and compare patient and procedural variables that are associated with a high radiation dose exposure and worse clinical outcomes between transradial arterial (TRA) and transfemoral arterial (TFA) approaches.

DESIGN

This was a retrospective analysis.

SETTING

A community hospital during the initial phase of adopting a TRA-first approach.

PARTICIPANTS

A resultant 215 subjects who only underwent diagnostic cerebral angiograms (DCA) after excluding all therapeutic procedures and patients under 18 years.

INTERVENTIONS

Only DCA from 1 May 2018 to 31 January 2021.

MAIN OUTCOME MEASURES

We compared radiation exposure parameters (total fluoroscopy time (FT), total radiation dose (TD) and dose area product (DAP), number of vessels injected and Patient-Reported Global Health Physical and Mental Outcome Scores (PROGHS) at 30 days postprocedure between groups.

RESULTS

FT was significantly greater in TRA compared with TFA (p<0.001). In addition, TRA had a significantly higher TD (p=0.002) and DAP (p=0.005) when compared with TFA. Analysis of only 6-vessel DCAs also showed that TRA had a significantly higher FT, DAP and TD in comparison to TFA. Despite observing a longer FT in TRA, results showed fewer vessels injected and a notably lower success rate in acquiring a 6-vessel DCA using the TRA. Further analysis of the effect of vessel number on FT using general linear models showed that with every increase of one vessel, the FT increases by 2.2 min for TRA (p<0.001; 95% CI 1.03 to 3.36) and by 1.3 min for TFA (p<0.001; 95% CI 0.72 to 1.83). There was no significant difference between groups in PROGHS mental and physical t-scores at 30 days postprocedure, even though our cohort showed a significantly greater percentage of TRA procedures done in the outpatient setting.

CONCLUSIONS

Adopting a TRA first approach for DCAs may be initially associated with a higher radiation dose for the patient. Better strategies and devices are needed to mitigate this effect.

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.

Radial artery access for neuroendovascular procedures: safety review and complications

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 reviewed anatomical considerations for safe and easy neuroendovascular procedures from a transradial approach. In this second part of the review series, we aim to (1) summarize evidence for safety of the transradial approach, and (2) explain complications and their management.

Complications of transradial versus transfemoral access for neuroendovascular procedures: a meta-analysis

BACKGROUND

Transradial access (TRA) has gained increased usage among neurointerventionalists. However, the overall safety profile of access site complications (ASCs) and non-access site complications (NASCs) of TRA versus transfemoral access (TFA) for neuroendovascular procedures remains unclear.

METHODS

A systematic literature review and meta-analysis using a random effects model was conducted to investigate the pooled odds ratios (OR) of ASCs and NASCs. Randomized, case-control, and cohort studies comparing access-related complications were analyzed. An assessment of study heterogeneity and publication bias was also completed.

RESULTS

Seventeen comparative studies met the inclusion criteria for final analysis. Overall, there was a composite ASC rate of 1.8% (49/2767) versus 3.2% (168/5222) for TRA and TFA, respectively (P<0.001). TRA was associated with a lower odds of ASC compared with TFA (OR 0.42; 95% CI 0.25 to 0.68, P<0.001, I²=31%). There was significantly lower odds of complications within the intervention and diagnostic subgroups. For NASC, TRA had a lower composite incidence of complications than TFA at 1.2% (31/2586) versus 4.2% (207/4909), P<0.001). However, on meta-analysis, we found no significant difference overall between TRA and TFA for NASCs (OR 0.79; 95% CI 0.51 to 1.22, P=0.28, I²=0%), which was also the case on subgroup analysis.

CONCLUSION

On meta-analysis, the current literature indicates that TRA is associated with a lower incidence of ASCs compared with TFA, but is not associated with a lower rate of NASCs.

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.

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.

Transradial cerebral angiography becomes more efficient than transfemoral angiography: lessons from 500 consecutive angiograms

BACKGROUND

Transradial arterial access (TRA) for cerebral diagnostic angiography is associated with fewer access site complications than transfemoral access (TFA). However, concerns about increased procedure time and radiation exposure with TRA may slow its adoption. Our objective was to measure TRA rates of success and fluoroscopy time per vessel after 'radial-first' adoption and to compare these rates to those obtained with TFA.

METHODS

We examined 500 consecutive cerebral angiograms on an intent-to-treat basis during the first full year of radial-first adoption, recording patient and procedural characteristics and outcomes.

RESULTS

Over a 9-month period at a single center, 457 of 500 angiograms (91.4%) were performed with intent-to-treat via TRA, and 431 cases (86.2%) were ultimately performed via TRA. One patient (0.2%) experienced a temporary neurologic deficit in the TRA group, and none (0%) did in the TFA group (p=0.80). The mean±SD fluoroscopy time per vessel decreased significantly from the first half of the study to the second half for TRA (5.0±3.8 vs 3.4±3.5 min/vessel; p<0.001), while TFA time remained unchanged (3.7±1.8 vs 3.5±1.4 min/vessel; p=0.69). The median fluoroscopy time per vessel for TRA became faster than that for TFA after 150 angiograms.

CONCLUSION

Of 500 consecutive angiograms performed during the first full year of radial-first implementation, 86.2% were performed successfully using TRA. TRA efficiency exceeded that of TFA after 150 angiograms. Concerns about the length of procedure or radiation exposure should not be barriers to TRA adoption.

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.

#RadialFirst and #RadialForNeuro: A descriptive analysis of Twitter conversations regarding transradial access

BACKGROUND

Transradial access for neurointerventional procedures was adopted and modified from cardiovascular intervention and is increasingly established as a safe and effective alternative to transfemoral catheterization. As social media influences public opinion on medical treatment, this study analyzes Twitter conversations to elucidate social media's depiction of transradial access as a neurointerventional tool.

MATERIALS AND METHODS

Twitter hashtags #RadialFirst and #RadialForNeuro were evaluated using a mixed-method analysis of quantitative social media metrics and qualitative thematic analysis.

RESULTS

Between January 2015 and April 2020, 104,146 tweets from 141 countries employed the hashtag #RadialFirst (2015 (1); 2016 (0); 2017 (22,804); 2018 (33,074); 2019 (38,352); 2020 (9,915 January-April)). These generated 226,909,374 impressions and were retweeted 80,120 times by 13,707 users. Media was present in 62.5% of tweets (e.g. wrist image, angiographic runs) but only 14.5% had a reference article. Physicians authored 70.8% of tweets; interventional cardiologists accounted for 83% of top 100 influencers. #RadialForNeuro is more nascent (6 posts in 2019; 323 posts January-April 2020), with 392,662 impressions, and 254 retweets by 177 users; physicians authored 35.6%. Compared to #RadialFirst, #RadialforNeuro tweets were more likely to include media (76%), less likely to include citations (9.7%), and more likely to discuss complications and troubleshooting techniques.

CONCLUSION

Twitter activity regarding transradial access permits information dissemination and discussion on approach benefits and challenges. However, many posts arise from non-physician sources and lack links to peer-reviewed publication. The public should be mindful that tweets may reflect opinions, rather than experience or scientific evidence.

Upper extremity transvenous access for neuroendovascular procedures: an international multicenter case series

BACKGROUND

Radial artery access for transarterial procedures has gained recent traction in neurointerventional due to decreased patient morbidity, technical feasibility, and improved patient satisfaction. Upper extremity transvenous access (UETV) has recently emerged as an alternative strategy for the neurointerventionalist, but data are limited. Our objective was to quantify the use of UETV access in neurointerventions and to measure failure and complication rates.

METHODS

An international multicenter retrospective review of medical records for patients undergoing UETV neurointerventions or diagnostic procedures was performed. We also present our institutional protocol for obtaining UETV and review the existing literature.

RESULTS

One hundred and thirteen patients underwent a total of 147 attempted UETV procedures at 13 centers. The most common site of entry was the right basilic vein. There were 21 repeat puncture events into the same vein following the primary diagnostic procedure for secondary interventional procedures without difficulty. There were two minor complications (1.4%) and five failures (ie, conversion to femoral vein access) (3.4%).

CONCLUSIONS

UETV is safe and technically feasible for diagnostic and neurointerventional procedures. Further studies are needed to determine the benefit over alternative venous access sites and the effect on patient satisfaction.

CTA-Based Patient-Tailored Femoral or Radial Frontline Access Reduces the Rate of Catheterization Failure in Chronic Subdural Hematoma Embolization

BACKGROUND AND PURPOSE

Chronic subdural hematoma embolization, an apparently simple procedure, can prove to be challenging because of the advanced age of the target population. The aim of this study was to compare 2 arterial-access strategies, femoral versus patient-tailored CTA-based frontline access selection, in chronic subdural hematoma embolization procedures.

MATERIALS AND METHODS

This was a monocentric retrospective study. From the March 15, 2018, to the February 14, 2019 (period 1), frontline femoral access was used. Between February 15, 2019, and March 30, 2020 (period 2), the choice of the frontline access, femoral or radial, was based on the CTA recommended as part of the preoperative work-up during both above-mentioned periods. The primary end point was the rate of catheterization failure. The secondary end points were the rate of access site conversion and fluoroscopy duration.

RESULTS

During the study period, 124 patients (with 143 chronic subdural hematomas) underwent an embolization procedure (mean age, 74 [SD, 13] years). Forty-eight chronic subdural hematomas (43 patients) were included during period 1 and were compared with 95 chronic subdural hematomas (81 patients) during period 2. During the first period, 5/48 (10%) chronic subdural hematoma embolizations were aborted due to failed catheterization, significantly more than during period 2 (1/95, 1%; P = .009). The rates of femoral-to-radial (P = .55) and total conversion (P = .86) did not differ between the 2 periods. No significant difference was found regarding the duration of fluoroscopy (P = .62).

CONCLUSIONS

A CTA-based patient-tailored choice of frontline arterial access reduces the rate of catheterization failure in chronic subdural hematoma embolization procedures.

Adoption of the Transradial Approach for Neurointerventions: A National Survey of Current Practitioners

OBJECTIVES

The transradial approach (TRA) is technically feasible for both diagnostic and therapeutic neurointerventions. It improves patient comfort and is not associated with increased procedural complications when compared to the transfemoral approach (TFA). To date, no studies have looked at barriers to adoption of TRA in the neurointerventionalist community. This study aims to obtain neurointerventionalist perspectives on their adoption of TRA.

MATERIALS AND METHODS

Online survey distributed to neurointerventionalists.

RESULTS

A total of 55 neurointerventionalists, 52 of whom utilized TRA, responded to our survey. Overall, participants were not concerned about TRA's technical feasibility for diagnostic or therapeutic neurointerventions or about procedural complications. Most of our cohort adopted TRA due to its increased patient comfort and to reduce access site complications. In-institution interventionalists were strongly perceived to be the most effective method of teaching TRA when compared to other methods. Catheters and equipment issues were reported by about 30% of our cohort as a barrier to TRA adoption.

CONCLUSIONS

The neurointerventionalist community largely perceives TRA to be technically feasible and was not concerned about its procedural complications. In-person institutionalists are strongly perceived to be the most effective method of teaching the approach. A significant barrier to adoption seems to be related to catheters and equipment issues.

Transradial Approach for Neuroendovascular Procedures: A Single-Center Review of Safety and Feasibility

BACKGROUND AND PURPOSE

In recent years, the transradial approach has become more widely adopted for neuroendovascular procedures. The purpose of this study was to evaluate the safety and feasibility of a transradial approach and distal transradial access for neuroendovascular procedures in a single center.

MATERIALS AND METHODS

Retrospective analysis was performed for all patients who underwent transradial approach or distal transradial access neuroendovascular procedures from January 2016 to August 2019 at a single center. Exclusion criteria included a Barbeau D waveform, a radial artery of <2 mm on sonographic evaluation, and known radial artery occlusion. Procedures were evaluated for technical success (defined as successful radial artery access and completion of the intended procedure without crossover to an auxiliary access site), complications, and adverse events during follow-up at 30 days.

RESULTS

The transradial approach or distal transradial access was attempted in 279 consecutive patients (58.1% women; median age, 57.7 years) who underwent 328 standard or distal transradial approach procedures. Two-hundred seventy-nine transradial approach and 49 distal transradial approach procedures were performed (cerebral angiography [n = 213], intracranial intervention [n = 64], head and neck intervention [n = 30], and stroke intervention [n = 21]). Technical success was 92.1%. Immediate adverse events (2.1%) included radial access site hematoma (n = 5), radial artery occlusion (n = 1), and acute severe radial artery spasm (n = 1). Thirty-day adverse events (0.3%) included a radial artery pseudoaneurysm (n = 1). Twenty-six cases (7.9%) required crossover to transfemoral access.

CONCLUSIONS

The transradial approach for neuroendovascular procedures is safe and feasible across a wide range of neuroendovascular interventions.

Radial vs. Femoral Artery Access for Procedural Success in Diagnostic Cerebral Angiography : A Randomized Clinical Trial

BACKGROUND AND PURPOSE

Radial artery access has become the standard of care in percutaneous coronary procedures due to demonstrated patient safety and comfort benefits; however, uptake of radial access for diagnostic cerebral angiography has been limited by practitioner concerns over the ability to achieve procedural success. We aimed to provide randomized clinical trial evidence for the non-inferiority of radial access to achieve procedural success.

MATERIAL AND METHODS

Monocentric open label randomized controlled trial with a non-inferiority design and blinded primary outcome assessment. Adult patients referred in-hours for diagnostic cerebral angiography were eligible. Participants underwent permuted block randomization to radial or femoral artery access with an intention-to-treat analysis. The primary outcome was procedural success, defined as selective cannulation and/or diagnostic angiography of predetermined supra-aortic vessels of interest. The non-inferiority limit was 10.0%. Secondary outcomes included postprocedural complications, fluoroscopy and procedural times, radiation dose, contrast volume and rates of vertebral artery cannulation.

RESULTS

A total of 80 participants were enrolled (female 42, male 38, mean age 47.0 years, radial access group n = 43, femoral n = 37). One patient in the radial group was excluded after enrollment due to insufficient sonographic radial artery internal diameter. Procedural success was achieved in 41 of 42 participants in the radial group (97.6%) and 36 of 37 in the femoral group (97.3%). The difference between groups was -0.3% (one-sided 95% confidence interval, CI 6.7%) and the null hypothesis was rejected.

CONCLUSION

Radial artery access is non-inferior to femoral artery access for procedural success in cerebral angiography. A large multicenter trial is recommended as the next step.

Forming the Simmons Catheter for Cerebral Angiography and Neurointerventions via the Transradial Approach-Techniques and Operative Videos

OBJECTIVE

Transradial access has been used increasingly for diagnostic cerebral angiography and neurointerventions. This requires development of a new skillset. Forming the Simmons catheter to catheterize the cerebral vessels is the most fundamental. Patient anatomy can complicate the formation of the Simmons catheter and the success of the procedure. The aim of this paper is to identify and describe the techniques that can be used transradially to facilitate the formation of the Simmons catheter for catheterization of the cerebral vessels.

METHODS

We reviewed our series of 85 cerebral angiograms performed via a transradial approach at our institution between 2018 and 2019. We identified the techniques employed to form the Simmons catheter and compiled operative videos demonstrating each technique and its nuances.

RESULTS

We have identified 7 techniques used to form the Simmons catheter from a right radial approach: in the ascending aorta, in the descending aorta, in the aortic arch, by deflecting the catheter off of the aortic valve with the glidewire in the common carotid artery, by deflecting the catheter off of the aortic valve with the glidewire in the descending aorta, and directly in the right or left common carotid arteries. We have identified that formation of the Simmons catheter from a left radial approach is most easily done in the descending aorta.

CONCLUSIONS

Transradial artery access has become increasingly common in cerebral angiography and neurointerventions. We describe techniques used for the formation of the Simmons catheter, a fundamental skill necessary for transradial cerebral angiogram or neurointervention.

Rescue carotid puncture for ischemic stroke treated by endovascular therapy: a multicentric analysis and systematic review

BACKGROUND

Endovascular therapy (EVT) for acute ischemic stroke (AIS) can be challenging in older patients with supra-aortic tortuosity. Rescue carotid puncture (RCP) can be an alternative in case of supra-aortic catheterization failure by femoral access, but data regarding RCP are scarce. We sought to investigate the feasibility, effectiveness and safety of RCP for AIS treated by EVT.

METHODS

Patients treated by EVT with RCP were included from January 2012 to December 2019 in the Endovascular Treatment in Ischemic Stroke (ETIS) multicentric registry. Main outcomes included reperfusion rates ( ≥ TICI2B), 3 month functional outcome (modified Rankin Scale) and 3 month mortality. We also performed an additional systematic review of the literature according to the PRISMA checklist to summarize previous studies on RCP.

RESULTS

25 patients treated by EVT with RCP were included from the ETIS registry. RCP mainly concerned elderly patients (median age 85 years, range 73-92) with supra-aortic tortuosity (n=16 (64%)). Intravenous thrombolysis (IVT) was used for nine patients (36%). Successful reperfusion was achieved in 64%, 87.5% of patients were dependent at 3 months, and 3 month mortality was 45.8%. The systematic review yielded comparable results. In pooled individual data, there was a shift toward better functional outcome in patients with successful reperfusion (median (IQR) 4 (2-6) vs 6 (4-6), p=0.011).

CONCLUSION

RCP mainly concerned elderly patients admitted for AIS with anterior LVO with supra-aortic tortuosity. The procedure seemed feasible, notably for patients treated with IVT, and led to significant reperfusion rates at the end of procedure, but with pronounced unfavorable outcomes at 3 months. RCP should be performed under general anesthesia to avoid life-threatening complications and ensure airways safety. Finally, RCP led to low rates of closure complications, emphasizing that this concern should not withhold RCP, if indicated.

Distal radial artery (snuffbox) access for carotid artery stenting - Technical pearls and procedural set-up

PURPOSE

To report use of distal radial artery (dRA) access for carotid artery stenting (CAS) and to discuss procedural setup and technical considerations for a successful intervention.

METHODS

A retrospective review of our prospective neurointerventional database of CAS was conducted between May 2019 and March 2020. All CAS cases via dRA in the anatomical snuffbox were identified. Patient demographics, clinical information, procedural and radiographic data was collected.

RESULTS

22 CAS procedures in 20 patients via dRA were identified. Patients' mean age was 69.4 years (range 53-87 years). 3 patients were female. Mean radial artery diameter was 2.1 mm (range 1.6-2.8 mm). dRA access was achieved in all cases. Conversion to femoral access was required in 2 cases (9.1%) due to persistent radial artery vasospasm resulting in patient discomfort despite multiple additional doses of intraarterial vasodilators and added intravenous sedation as well as tortuous vessel anatomy and limited support of the catheters in a type 3 aortic arch for left CAS.

CONCLUSION

Our preliminary experience with dRA access for CAS suggests this approach to be feasible and safe for patients. Technical considerations are important and preprocedural planning is necessary for a successful intervention. Catheter systems and devices specifically designed for radial access are needed to enable more interventionalists to safely perform neurointerventional procedures via wrist access.

Distal radial artery (snuffbox) access for carotid artery stenting - Technical pearls and procedural set-up

PURPOSE

To report use of distal radial artery (dRA) access for carotid artery stenting (CAS) and to discuss procedural setup and technical considerations for a successful intervention.

METHODS

A retrospective review of our prospective neurointerventional database of CAS was conducted between May 2019 and March 2020. All CAS cases via dRA in the anatomical snuffbox were identified. Patient demographics, clinical information, procedural and radiographic data was collected.

RESULTS

22 CAS procedures in 20 patients via dRA were identified. Patients' mean age was 69.4 years (range 53-87 years). 3 patients were female. Mean radial artery diameter was 2.1 mm (range 1.6-2.8 mm). dRA access was achieved in all cases. Conversion to femoral access was required in 2 cases (9.1%) due to persistent radial artery vasospasm resulting in patient discomfort despite multiple additional doses of intraarterial vasodilators and added intravenous sedation as well as tortuous vessel anatomy and limited support of the catheters in a type 3 aortic arch for left CAS.

CONCLUSION

Our preliminary experience with dRA access for CAS suggests this approach to be feasible and safe for patients. Technical considerations are important and preprocedural planning is necessary for a successful intervention. Catheter systems and devices specifically designed for radial access are needed to enable more interventionalists to safely perform neurointerventional procedures via wrist access.

Transradial approach for diagnostic cerebral angiograms in the elderly: a comparative observational study

Background

The transradial approach (TRA) reduces mortality, morbidity, access site complications, hospital cost, and length of stay while maximizing patient satisfaction. We aimed to assess the technical success and safety of TRA for elderly patients (aged ≥75 years).

Methods

A retrospective chart review and comparative analysis was performed for elderly patients undergoing a diagnostic cerebral angiogram performed via TRA versus transfemoral approach (TFA). Also, a second comparative analysis was performed among the TRA cohort between elderly patients and their younger counterparts.

Results

Comparative analysis in the elderly (TRA vs TFA) showed no significant differences for contrast dose per vessel (43.7 vs 34.6 mL, P=0.106), fluoroscopy time per vessel (5.7 vs 5.2 min, P=0.849), procedure duration (59.8 vs 65.2 min, P=0.057), conversion rate (5.8% vs 2.9%, P=0.650), and access site complications (2.3% vs 2.9%, P=1.00). Radiation exposure per vessel (18.9 vs 51.9 Gy cm2, P=0.001) was significantly lower in the elderly TRA group.

The second comparison (TRA in elderly vs TRA in the young) showed no significant differences for contrast dose per vessel (43.7 vs 37.8 mL, P=0.185), radiation exposure per vessel (18.9 vs 16.5 Gy cm2, P=0.507), procedure duration (59.8 vs 58.3 min, P=0.788), access site complication (2.3% vs 1.7%, P=0.55), and conversation rate (5.8% vs 1.8%, P=0.092). A trend for prolonged fluoroscopy time per vessel (5.7 vs 4.7 min, P=0.050) was observed in the elderly TRA group.

Conclusions

TRA is a technically feasible and safe option for diagnostic neurointerventional procedures in the elderly. Our small elderly cohort was not powered enough to show a significant difference in terms of access site complications between TRA and TFA.