The ACRA Anatomy Study (Assessment of Disability After Coronary Procedures Using Radial Access): A Comprehensive Anatomic and Functional Assessment of the Vasculature of the Hand and Relation to Outcome After Transradial Catheterization

Open Radial Artery Study

Radial artery occlusion (RAO) has been the most common postprocedural complication of transradial artery access. The optimal method of prevention of RAO is still lacking. In our study, we aimed to evaluate the effect of patent hemostasis on early (24 hours) and late (2 weeks) RAO prevention. The Open Radial Artery Study was a single-arm, prospective, and multicenter study. The primary end points were early and late RAO at the vascular access site after transradial coronary procedures. Secondary end points were access site hematoma, pseudoaneurysm formation, arteriovenous fistula, and nerve injury. A total of 2,181 patients were analyzed (67% male, mean age 68 years). The mean interventional duration and hemostatic times were 75.6 ± 55.6 and 60 ± 5.6 minutes, respectively. Radial artery spasm occurred in 10% of patients (n = 218). Catheter kinking, radial artery rupture, or dissection were not observed during the procedure. RAO, hematoma, pseudoaneurysm, arteriovenous fistula, or nerve damage was not observed in any of the patients in the early or late period. In patients who undergo coronary diagnostic or interventional procedures through transradial artery access, the patent hemostasis method seems a critical step in the prevention of early and late RAO.

Variations in Superficial Palmar Arch: Case Series with Clinico-anatomical Perspective

The superficial palmar arch (SPA) is an important anastomotic network primarily formed by the superficial branch of the ulnar artery with one of the superficial branches of the radial artery. SPA variations were observed in three out of 20 cadaveric hand specimens. Two cases of unilateral incomplete SPA and the third case of a unilateral ulnar-to-median complete SPA were recorded. The incomplete SPA was located superficial to the flexor digitorum tendons and deep to the palmar aponeurosis. SPA in the remaining 17 hands was anatomically normal, with major contributions from the superficial palmar branch of the ulnar artery and minor contributions from the superficial palmar branch of the radial artery. These variations are clinically important, especially during procedures like arterial blood sampling, cardiac catheterization, and hemodialysis. Thus, anatomical variabilities in this region may cause complications with vascular occlusion if not ascertained before the procedure.

Index Digit Necrosis as a Complication of Radial Artery Cannulation

Arterial access is therapeutically and diagnostically useful. Its clinical utility is vast, and associated complications are infrequent. However, some unfortunate patients progress to disastrous outcomes. Luckily, ischemic hand complications are rare. Hand ischemia threatens independence and quality of life, thus warranting vigilance. We present a case of index digit necrosis as a complication of arterial cannulation in a 30-year-old patient with end-stage renal disease admitted to an intensive care unit.

Feasibility and Safety of Flow Diversion in the Treatment of Intracranial Aneurysms via Transradial Approach: A Single-Arm Meta Analysis

Background

While studies have confirmed that flow diversion (FD) can treat intracranial aneurysms via transradial approach (TRA), it remains unclear whether their treatment ultimately impacts safety and feasibility. We aim to conduct a systematic review and meta-analysis assessing the safety and feasibility after FD treatment of intracranial aneurysms via TRA.

Methods

PubMed, EMBASE, and Web of Science were systematically reviewed. The primary outcomes were the success rate and the access-related complications of deploying FD via TRA. Meta-analysis was performed using a random or fixed effect model based on heterogeneity. And the publication bias was evaluated using a funnel plot. This study was registered with PROSPERO, number CRD42021244448.

Results

Data from 8 studies met inclusion criteria (250 non-duplicated patients). The success rate was 93% (95% confidence interval [CI] 0.86–0.98; I² = 61.05%; p = 0.01). The access-related complications rate was 1% (95% CI 0–0.03; I² = 0.00%; p < 0.01). The mainly access-related complications included radial artery spasm (85.7%) and radial artery occlusion (14.3%). The TRA convert to transfemoral approach (TFA) was 7% (95% CI 0.02–0.14; I² = 61.05%; p = 0.01).

Conclusions

Although TFA is still the main access for FD in the treatment of intracranial aneurysms, the TRA also has a higher success rate and lower access-related complications rate. With the improvement of future experience and equipment, the TRA may become the main access for FD which has more advantages. Future studies should design prospective, multicenter randomized controlled studies for long-term follow-up.

International Hand Function Study Following Distal Radial Access: The RATATOUILLE Study

BACKGROUND

Distal radial access (DRA) has been proposed to improve procedure ergonomics and favor radial artery patency. Although promising data, nothing is known on evolving hand function after DRA.

OBJECTIVES

This study sought to comprehensively evaluate hand function in patients undergoing DRA.

METHODS

Real-world patients undergoing DRA undertook a thorough multimodality assessment of hand function implementing multidomain questionnaires (Disabilities of the Arm, Shoulder and Hand and Levine-Katz), and motor (pinch grip test) and sensory (Semmes-Weinstein monofilaments test) examinations of both hands. All assessments were performed at preprocedural baseline and planned at 1-, 6-, and 12-month follow-up (FU). Adverse clinical and procedural events were documented too.

RESULTS

Data of 313 patients (220 men, age 66 ± 10 years) from 9 international centers were analyzed. The Disabilities of the Arm, Shoulder and Hand and the Levine-Katz scores slightly improved from baseline to FU (P = 0.008 and P = 0.029, respectively). Pinch strength mildly improved from baseline to FU (P < 0.001 for both the left and right hands). Similarly, touch pressure threshold appeared to faintly improve in both the left and right hands (P < 0.012 for all the sites). For both motor and sensory function tests, comparable findings were found for the DRA hand and the contralateral one, with no significant differences between them. Repeated assessment of all tests over all FU time points similarly showed lack of worsening hand function. Access-related adverse events included 19 harmless bleedings and 3 forearm radial artery and 3 distal radial artery occlusions. None affected hand function at FU.

CONCLUSIONS

In a systematic multidimensional assessment, DRA was not associated with hand function impairment. Moreover, DRA emerges as a safe alternative vascular access.

Distal versus conventional radial access for coronary angiography and intervention: Design and rationale of DISCO RADIAL study

BACKGROUND

Transradial access (TRA) has become the default access method for coronary diagnostic and interventional procedures. As compared to transfemoral access, TRA has been shown to be safer, cost-effective and more patient-friendly. Radial artery occlusion (RAO) represents the most frequent complication of TRA, and precludes future coronary procedures through the radial artery, the use of the radial artery as a conduit for coronary artery bypass grafting or as arteriovenous fistula for patients on hemodialysis. Recently, distal radial access (DRA) has emerged as a promising alternative to TRA, yielding potential for minimizing the risk of RAO. However, an international multicenter randomized comparison between DRA, and conventional TRA with respect to the rate of RAO is still lacking.

TRIAL DESIGN

DISCO RADIAL is a prospective, multicenter, open-label, randomized, controlled, superiority trial. A total of 1300 eligible patients will be randomly allocated to undergo coronary angiography and/or percutaneous coronary intervention (PCI) through DRA or TRA using the 6 Fr Glidesheath Slender sheath introducer. Extended experience with both TRA and DRA is required for operators' eligibility and optimal evidence-based best practice to reduce RAO systematically implemented by protocol. The primary endpoint is the incidence of forearm RAO assessed by vascular ultrasound at discharge. Several important secondary endpoints will also be assessed, including access-site cross-over, hemostasis time, and access-site related complications.

SUMMARY

The DISCO RADIAL trial will provide the first large-scale multicenter randomized evidence comparing DRA to TRA in patients scheduled for coronary angiography or PCI with respect to the incidence of RAO at discharge.

Extremity Dysfunction After Large-Bore Radial and Femoral Arterial Access

Background

The use of large‐bore (LB) arterial access and guiding catheters has been advocated for complex percutaneous coronary intervention. However, the impact of LB transradial access (TRA) and transfemoral access (TFA) on extremity dysfunction is currently unknown.

Methods and Results

The predefined substudy of the COLOR (Complex Large‐Bore Radial PCI) trial aimed to assess upper and lower‐extremity dysfunction after LB radial and femoral access. Upper‐extremity function was assessed in LB TRA‐treated patients by the Quick Disabilities of the Arm, Shoulder, and Hand questionnaire and lower‐extremity function in LB TFA‐treated patients by the Lower Extremity Functional Scale questionnaire. Extremity pain and effect of access site complications and risk factors on extremity dysfunction was also analyzed. There were 343 patients who completed analyzable questionnaires. Overall, upper and lower‐extremity function did not decrease over time when LB TRA and TFA were used for complex percutaneous coronary intervention, as represented by the median Quick Disabilities of the Arm, Shoulder, and Hand score (6.8 at baseline and 2.1 at follow‐up, higher is worse) and Lower Extremity Functional Scale score (56 at baseline and 58 at follow‐up, lower is worse). Clinically relevant extremity dysfunction occurred in 6% after TRA and 9% after TFA. A trend for more pronounced upper‐limb dysfunction was present in female patients after LB TRA (P=0.05). Lower‐extremity pain at discharge was significantly higher in patients with femoral access site complications (P=0.02).

Conclusions

Following LB TRA and TFA, self‐reported upper and lower‐limb function did not decrease over time in the majority of patients. Clinically relevant limb dysfunction occurs in a small minority of patients regardless of radial or femoral access.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03846752.

Radial artery occlusion after conventional and distal radial access: Impact of preserved flow and time-to-hemostasis in a propensity-score matching analysis of 1163 patients

OBJECTIVES

To compare incidence of forearm radial artery occlusion (RAO) and hemostasis characteristics between distal and conventional transradial approach (DRA and TRA, respectively).

BACKGROUND

DRA has the potential advantage of reducing RAO. DRA effectively reduces time-to-hemostasis, however its role on preserving flow in the radial artery (PF) during hemostasis and consequent impact on RAO remains speculative.

METHODS

Eight hundred thirty-seven patients with TRA were previously enrolled in a prospective registry investigating the relationship of residual anticoagulation and RAO. Three hundred twenty-six additional patients with DRA were added to the cohort and matched to the original cohort by propensity score. The composite end-point of RAO at forearm and distal site of puncture (dRAO) was evaluated as secondary end-point.

RESULTS

RAO occurred in 4.8% (41 of 837) of patients undergoing TRA and in 0% (0 of 326) of those undergoing DRA (p < 0.0001). DRA was associated with higher percentage of PF (97.2% vs. 78.5% in TRA group, p < 0.0001) and reduced time-to-hemostasis (147 ± 99 min vs. 285 ± 138 min, p < 0.0001). After matching, hemostasis characteristics were still significant different (PF 95.7% vs. 90.1%, p = 0.023, and 190 ± 92 vs. 323 ± 162 min, p < 0.0001) with reduction in the incidence of RAO (0 of 213, 0% vs. 7 of 213, 3.3%, p = 0.0015). dRAO occurred in one case (0.3% and 0.5% after matching, p < 0.0001 and p = 0.032 compared to TRA).

CONCLUSIONS

DRA was associated with lower rates of RAO compared to TRA. This effect is potentially explained by reduced time-to-hemostasis and maintained flow at the wrist during hemostasis.

Dual-center study comparing transradial and transfemoral approaches for flow diversion treatment of intracranial aneurysms

BACKGROUND

The transfemoral approach (TFA) has been the traditional approach for neurointerventional cases. While the TFA allows for triaxial support in flow diverting stent cases, it is associated with access site complications. Recently, the transradial approach (TRA) has emerged as a safer alternative to the TFA. To the best of our knowledge, there have only been single-center studies comparing outcomes in flow diverter cases for these approaches. We demonstrate the safety and feasibility of the TRA for placement of flow diverting stents in the treatment of unruptured intracranial aneurysms at two high-volume centers.

MATERIALS AND METHODS

We performed a retrospective review of prospectively collected institutional databases at two high-volume neuroendovascular centers. Cases from 2016 to 2018 of unruptured intracranial aneurysms treated by flow diverting stenting accessed through either the TRA or the TFA were compared. Patient demographics, procedural and radiographic metrics including location and size of the aneurysm, size, and length of the flow diverter implant, and fluoroscopic time were recorded. Puncture site complications and length of hospital stay were also included in the data analysis.

RESULTS

There were three out of 29 TRA cases which were converted to the TFA. None of the TRA patients experienced site complications, whereas three TFA patients experienced site complications. While TRA and TFA patients did not differ significantly in their exposure to radiation, TRA patients experienced shorter hospital stays.

CONCLUSIONS

While long-term studies are still lacking regarding this approach, we demonstrate that the TRA is a safe and feasible approach for flow diverter stent placement.

Ultrasound-guided access to the distal radial artery at the anatomical snuffbox for catheter-based vascular interventions: a technical guide

Conventional radial access has been shown to have many advantages over the transfemoral approach. The risk of potential radial artery occlusion and subsequent hand ischaemia can be reduced further by accessing the vessel distally at the anatomical snuffbox, allowing maintenance of antegrade flow to the hand by the superficial palmar arch branch. Additional potential advantages of distal radial access in comparison to the conventional radial approach at the wrist include fewer puncture-site complications and faster post-procedural haemostasis as the vessel is very superficial. Furthermore, it provides another safe, non-femoral option for vascular access. The use of ultrasound guidance enables the operator to identify important anatomical landmarks and avoid injuring adjacent structures. We provide a detailed step-by-step guide for performing distal radial access using sonographic and anatomical correlation, thereby facilitating safe access and optimising technical success.

Double-blind, single-center, randomized study evaluating the effectiveness of Isosorbide Mononitrate in preventing radial artery occlusion compared to placebo in patients undergoing elective percutaneous coronary procedure: study protocol

Objectives: The primary objective of this study will be to evaluate the efficacy of subcutaneous and peri-arterial isosorbide mononitrate in preventing occlusion of the radial artery (ORA) after percutaneous coronary procedures (PCP) performed by the transradial approach (TRA). As secondary objectives, define the incidence of ORA in the institution and assess variables related to the risk of occlusion. Methods: Single-center, double-blind, randomized study, including in- and outpatients from a high complexity hospital, admitted to performing PCP, diagnostic or therapeutic, by TRA, in stable coronary conditions (elective) or acute coronary syndrome. The sample will be randomly divided into a group that will receive the medication and a control group. All participants will be submitted to palpatory assessment of radial artery patency and the Barbeau inverse test within 24 h and seven days after the procedure. This will be the first study to evaluate isosorbide mononitrate as an accessible and inexpensive pharmacological method for preventing OAR after PCP by VTR.

Total Radial Artery Occlusion Following Transradial Access: Complete Recanalization via the Anatomical Snuffbox

Radial artery occlusion (RAO) is a common complication of procedures requiring transradial access. While radial artery occlusion is most often asymptomatic, there is an elevated prevalence of ischemia in patients with inadequate palmar arch blood supply. Furthermore, treatment options for RAO remain severely limited. We describe a novel technique using distal transradial access in the anatomic snuffbox to recanalize a totally occluded thrombosed radial artery.

Intraoperative Invasive Blood Pressure Monitoring in Flap-Based Breast Reconstruction: Does It Change Outcomes?

Despite the lack of guidelines regarding the use of intra-arterial lines in postmastectomy breast reconstruction (PMBR), they continue to be used in this setting. In this study of patients undergoing PMBR, we aimed to (1) identify factors associated with intra-arterial line placement, (2) analyze the correlation between intra-arterial monitoring and noninvasive blood pressure (NIBP) monitoring, and (3) investigate whether hemodynamic management differs significantly between patients undergoing intra-arterial blood pressure monitoring versus NIBP.

Distal radial access for cerebral aneurysm embolization

OBJECTIVES

To demonstrate the feasibility and safety of distal radial access for embolization of ruptured and unruptured cerebral aneurysms.

METHODS

This study is a retrospective review of our prospective cerebral aneurysm embolization database. Between January and September 2019, distal radial access was considered for consecutive subjects addressed for cerebral aneurysm embolization at our institution. All procedures were performed by the same experienced operator. Technical success was defined as distal radial access with insertion of the sheath and completion of the intervention without change of access site to conventional femoral access. Primary safety endpoint was the in hospital + 30 days incidence of radial artery occlusion. Secondary endpoints included intra-procedural complications and neurologic complications at discharge and at 30 days.

RESULTS

Fifty-seven patients with cerebral aneurysms underwent 61 embolization procedures. Twenty eight embolizations were performed using coils, 8 used a stent-assisted coil technique, 22 used a balloon-assisted coil technique, and 3 used a flow diverter. One patient (1.6%) required crossover to femoral access. Three patients developed coil-induced thrombus that required intra-arterial Tirofiban injections. Two patients were asymptomatic and one patient presented confusion due to right frontal ischemia. One periprocedural aneurysm rupture occurred without clinical impact. Radial artery occlusion and hand ischemia were not observed.

CONCLUSION

Findings of the present study showed the feasibility of distal transradial access for cerebral aneurysm embolization without increasing the risk of the procedure.

Reaccessing an occluded radial artery for neuroendovascular procedures: techniques and complication avoidance

BACKGROUND

Radial artery occlusion (RAO) occurs in 1% to 10% of cases following transradial arterial access (TRA) for neuroendovascular procedures. When repeat access is required in patients discovered to have RAO, a transfemoral approach is often used. This study reports experience with repeat TRA procedures at a single center and techniques for reaccessing an occluded radial artery in select patients.

METHODS

The electronic records of all patients who underwent multiple neuroendovascular procedures with an attempted TRA as the index procedure at a single center from July 2019 through February 2020 were reviewed.

RESULTS

There were 656 TRA attempts for diagnostic angiography or intervention from July 2019 through February 2020. A total of 106 patients underwent a repeated attempt at TRA. Techniques for reaccessing an occluded radial artery were implemented halfway through the study period. One hundred patients (94.3%) had a successful second radial catheterization. Six patients required conversion to a transfemoral approach: five for RAO and one for radial branch perforation during the index procedure. After we implemented our techniques for reaccess, four additional patients with RAO successfully underwent TRA. There were no short-term complications, including pain, vessel perforation, forearm hematoma, or hand ischemia, following successful repeat catheterization of a previously occluded radial artery.

CONCLUSION

RAO is not an absolute limitation for attempting TRA in patients undergoing repeat catheterization. Reaccessing the radial artery after occlusion is feasible for repeat neuroendovascular procedures.

Complex Large-Bore Radial percutaneous coronary intervention: rationale of the COLOR trial study protocol

INTRODUCTION

The radial artery has become the standard access site for percutaneous coronary intervention (PCI) in stable coronary artery disease and acute coronary syndrome, because of less access site related bleeding complications. Patients with complex coronary lesions are under-represented in randomised trials comparing radial with femoral access with regard to safety and efficacy. The femoral artery is currently the most applied access site in patients with complex coronary lesions, especially when large bore guiding catheters are required. With slender technology, transradial PCI may be increasingly applied in patients with complex coronary lesions when large bore guiding catheters are mandatory and might be a safer alternative as compared with the transfemoral approach.

METHODS AND ANALYSIS

A total of 388 patients undergoing complex PCI will be randomised to radial 7 French access with Terumo Glidesheath Slender (Terumo, Japan) or femoral 7 French access as comparator. The primary outcome is the incidence of the composite end point of clinically relevant access site related bleeding and/or vascular complications requiring intervention. Procedural success and major adverse cardiovascular events up to 1 month will also be compared between both groups.

ETHICS AND DISSEMINATION

Ethical approval for the study was granted by the local Ethics Committee at each recruiting center ('Medisch Ethische Toetsing Commissie Isala Zwolle', 'Commissie voor medische ethiek ZNA', 'Comité Medische Ethiek Ziekenhuis Oost-Limburg', 'Comité d'éthique CHU-Charleroi-ISPPC', 'Commission cantonale d'éthique de la recherche CCER-Republique et Canton de Geneve', 'Ethik Kommission de Ärztekammer Nordrhein' and 'Riverside Research Ethics Committee'). The trial outcomes will be published in peer-reviewed journals of the concerned literature.

TRIAL REGISTRATION NUMBER

NCT03846752.

The Neuro Radialist

Trans-radial approach (TRA) has been used in cardiac and peripheral interventional radiology practices for decades, because of safety and patient comfort. There is interest in TRA in the cerebrovascular field, with potential to replicate benefits over trans-femoral approach. TRA is technically more challenging and has a learning curve, which hinders its use as the first-line approach; however, as more neuro-interventionalists embrace TRA, techniques are being optimized simultaneously for supra-aortic vessel catheterization. This article describes advantages, patient selection, conventional and distal radial access, and detailed techniques of trans-radial catheterization for diagnostic angiography, as well as cerebrovascular interventions and its current limitations.

ACRA Perfusion Study

BACKGROUND

Transradial intervention (TRI) may impair digital perfusion with hand dysfunction as a result. However, the effect of TRI on digital perfusion has never been investigated, including the influence of variations of the collateral arterial network and the effect on hand dysfunction.

METHODS AND RESULTS

We investigated the effect of TRI on digital perfusion by laser Doppler perfusion imaging. Laser Doppler perfusion imaging was performed at baseline, during radial access, TR band application, and at discharge. We compared tissue perfusion of the homolateral thumb (access site) with the contralateral thumb (comparator) during radial access as primary outcome. The hand circulation was assessed with angiography. Upper extremity function was evaluated with the validated QuickDASH questionnaire at baseline and follow-up. A significant reduction of tissue perfusion was observed during radial access and TR band application in the homolateral thumb (-32%, -32%, respectively) and contralateral thumb (-34%, -21%, respectively). We detected no perfusion difference between the homolateral and contralateral thumb during radial access (217; interquartile range, 112-364 versus 209; interquartile range, 99-369 arbitrary flux units; P=0.59). Reduced perfusion of the thumb during radial access was not associated with incompleteness of the superficial palmar arch ( P=0.13). Digital perfusion improved at discharge, though it remained below baseline levels (homolateral -11% and contralateral -14%). Hand dysfunction at 18 months was not associated with TRI-induced perfusion reduction ( P=0.54).

CONCLUSIONS

TRI is safe. Digital perfusion is reduced in both hands during radial access and TR band application but is not associated with future loss of hand function and variations of the arterial hand supply.

Transradial Artery Access Complications

Transradial access (TRA) is favored over transfemoral access for performing coronary angiography and percutaneous coronary intervention due to the reduced risk for vascular and bleeding complications and the documented survival benefit in ST-segment–elevation myocardial infarction patients who undergo primary percutaneous coronary intervention. TRA complications can be categorized as intra- or postprocedural and further categorized as related to bleeding or nonbleeding issues. Major intra- and postprocedural complications such as radial artery perforation and compartment syndrome are rare following TRA. Their occurrence, however, can be associated with morbid consequences, including requirement for surgical intervention if not identified and treated promptly. Nonbleeding complications such as radial artery spasm and radial artery occlusion are typically less morbid but occur much more frequently. Strategies to prevent TRA complications are essential and include the use of contemporary access techniques that limit arterial injury. This document summarizes contemporary techniques to prevent, identify, and manage TRA complications.

Radial Artery Access for Percutaneous Cardiovascular Interventions: Contemporary Insights and Novel Approaches

Since its introduction, the transradial access for percutaneous cardiovascular procedures has been associated with several advantages as compared to transfemoral approach, and has become the default for coronary angiography and intervention. In the last 30 years, a robust amount of evidence on the transradial approach has been mounted, promoting its diffusion worldwide. This article provides a comprehensive review of radial artery access for percutaneous cardiovascular interventions, including the evidence from clinical trials of transradial vs. transfemoral approach, technical considerations, access-site complications and limitations, alternative forearm accesses (e.g., ulnar and distal radial artery), and ultimately the use of the radial approach for structural interventions.

Invasive Assessment of the Human Arterial Palmar Arch and Forearm Collateral Function During Transradial Access

Background:

The present study aimed to quantitatively measure the pressure-derived function of the palmar arch and forearm arterial collateral circulation during transradial access.

Methods and Results:

Palmar arch and forearm collateral function was determined using radial artery pressure signals in the nonobstructed vessel and during brief manual occlusions of the more proximal radial artery and of the radial plus ulnar arteries. Collateral flow index (CFI), the ratio of mean occlusive divided by mean nonocclusive arterial blood pressure, both subtracted by central venous pressure, was determined for CFI during radial artery occlusion (CFI rad ) and CFI during radial plus ulnar artery occlusion. Before invasive CFI measurements, arterial palmar arch and forearm function was tested noninvasively by the modified Allen test (MAT). Two hundred fifty patients undergoing transradial access coronary angiography were included in the study. CFI rad was equal to 0.802±0.150 (95% CI, 0.783–0.820). CFI during radial plus ulnar artery occlusion was equal to 0.424±0.188 (95% CI, 0.400–0.447). There was an inverse linear relation between CFI rad and MAT in seconds (s): MAT=64−63×CFI rad ( r 2 =0.229; P <0.0001). Two hundred eleven patients had a normal and 39 patients an abnormal (>15 seconds) MAT. The group with normal MAT had a CFI rad of 0.830±0.111, and patients with abnormal MAT had a CFI rad of 0.648±0.224 ( P <0.0001).

Conclusions:

Direct invasive hemodynamic assessment of the palmar arch and forearm arterial function reveals collateral supply to the briefly occluded in comparison to the patent radial artery of 0.802. During external occlusion of both radial and ulnar artery, CFI amounts to an unexpectedly high value of 0.424.

A Single-Center, Randomized, Controlled Comparison of the Transradial vs Transfemoral Approach for Cerebral Angiography: A Learning Curve Analysis

Purpose: To compare the characteristics and learning curve of the transfemoral approach (TFA) vs the transradial approach (TRA) for cerebral angiography. Materials and Methods: Between February 2016 and April 2017, 101 patients undergoing cerebral angiography were enrolled. Fifty-one patients (mean age 67 years; 40 men) were randomized to TFA and 50 (mean age 68 years; 41 men) to TRA using a computer-generated random table. The patients’ demographic and angiographic data were recorded and analyzed. The learning curve of a novice interventionist was analyzed for procedure time, puncture time, fluoroscopy time, and contrast volume as markers of technical proficiency with TFA compared with TRA. Median values are given with the interquartile range (IQR). Results: Procedure time [35 (IQR 30, 47.5) vs 31.0 (IQR 25.0, 48.9) minutes, p=0.16), fluoroscopy time [10.3 (IQR 7.6, 13.9) vs 9.4 (IQR 6.1, 17.6) minutes, p=0.70], contrast volume [105 (IQR 92, 120) vs 95.5 (IQR 90, 111.3) mL, p=0.13), radiation exposure [390.2 (IQR 268.2, 617.9) vs 455.8 (IQR 286.8, 602.3) mGy, p=0.74], and the number of catheter exchanges [1 (IQR 1, 3) vs 1 (IQR 1, 1), p=0.06] were not significantly different between the TFA and TRA groups, respectively, but puncture time was shorter with TFA than with TRA [0.6 (IQR 0.5, 1.1) vs 1 (IQR 0.6, 1.9) minutes, p=0.01]. The learning curve was steeper with TRA than with TFA in the beginning stages of training, but with increasing experience, the procedure and fluoroscopy times were better for TRA than for TFA. Training progress was made earlier in TRA. Conclusion: TRA is a reasonable alternative to TFA for cerebral angiography. TRA has a shorter learning curve for novice interventionists.

Technical Aspects of the Use of the Radial Artery in Coronary Artery Bypass Surgery

BACKGROUND

The radial artery has been used for coronary artery bypass surgery for more than 25 years. The recent confirmation of the clinical benefits associated with the use of the artery is likely to drive a new interest toward this conduit in the next few years.

METHODS

A group of surgeons with extensive experience in the systematic use of the radial artery summarize here the key technical aspects of the use of the conduit for coronary bypass operations.

RESULTS

Preoperative evaluation of the ulnar collateral circulation and attention to the characteristics of the target vessel are keys for the successful use of the radial artery. Open or endoscopic harvesting can be used, preferentially with the aid of the harmonic scalpel. The use of vasodilatory and antispastic protocols is probably important but poorly supported by the current evidence. The radial artery can be used for multiple grafting strategies with a variable degree of technical complexity.

CONCLUSIONS

With attention to few technical key points, the radial artery is a versatile conduit that can be easily introduced in the everyday practice of coronary artery bypass surgery.

Transradial Approach for Complex Anterior and Posterior Circulation Interventions: Technical Nuances and Feasibility of Using Current Devices

BACKGROUND

Despite several studies analyzing the safety of transradial access (TRA) for neurointervention compared to transfemoral approach (TFA), neurointerventionalists are apprehensive about implementing TRA. From our positive institutional experience, we now utilize TRA first line for a majority of our cases. Here, we present our single-institution experience.

OBJECTIVE

To determine safety and feasibility of TRA for neurointervention.

METHODS

Through retrospective review of patients receiving TRA for anterior and posterior circulation cerebrovascular interventions at our institution between December 2015 and January 2018, we present our experience regarding this transition, while focusing on technique, complications, feasibility, indications, and limitations.

RESULTS

One hundred five procedures were performed on 92 patients (anterior circulation: 77%; posterior circulation: 23%). Radial artery access was achieved in all patients. Twenty-nine cases constituted mechanical thrombectomy, 33 cases represented intracranial aneurysms treatments, and 33 cases included interventions like angioplasty, balloon test occlusion, chemotherapy delivery, and thrombolysis. TRA was used as second-line access to TFA in 5 instances due to aortic arch anomalies and atherosclerotic disease. Minor access-site complications were seen in 2.85% of patients. Ten procedures (9.0%) could not be completed with TRA, with crossover to TFA occurring in 7 cases.

CONCLUSION

TRA is safe and feasible for the majority of neurointerventional procedures and provides decreased risk of major access-site complications compared to TFA. Perceived limitations of TRA can likely be eliminated via operator experience and engineering ingenuity; thus, there is a role for TRA for neurointervention, especially in patients with increased risk of access-site complications from TFA.

Incidence and Clinical Course of Limb Dysfunction Post Cardiac Catheterization - A Systematic Review

BACKGROUND

We systematically reviewed the available literature on limb dysfunction after transradial access (TRA) or transfemoral access (TFA) cardiac catheterization. Methods and Results: MEDLINE and EMBASE were searched for studies evaluating any transradial or transfemoral procedures and limb function outcomes. Data were extracted and results were narratively synthesized with similar treatment arms. The TRA group included 15 studies with 3,616 participants and of these 3 reported nerve damage with a combined incidence of 0.16% and 4 reported sensory loss, tingling and numbness with a pooled incidence of 1.61%. Pain after TRA was the most common form of limb dysfunction (7.77%) reported in 3 studies. The incidence of hand dysfunction defined as disability, grip strength change, power loss or neuropathy was low at 0.49%. Although radial artery occlusion (RAO) was not a primary endpoint for this review, it was observed in 3.57% of the participants in a total of 8 studies included. The TFA group included 4 studies with 15,903,894 participants; the rates of peripheral neuropathy were 0.004%, sensory neuropathy caused by local groin injury and retroperitoneal hematomas were 0.04% and 0.17%, respectively, and motor deficit caused by femoral and obturator nerve damage was 0.13%.

CONCLUSIONS

Limb dysfunction post cardiac catheterization is rare, but patients may have nonspecific sensory and motor complaints that resolve over a period of time.

Altered Hand Temperatures Following Transradial Cardiac Catheterization: A Thermography Study

BACKGROUND

There is concern about potential detrimental effects of transradial access (TRA) on radial artery structure, endothelial and hand function. This thermography study evaluated TRA impact on hand microvascular perfusion.

METHODS AND RESULTS

We prospectively measured hand thermography, radial and ulnar artery size and blood flow velocities in both catheterization and non-catheterization hands at baseline and 30-days after TRA in 158 patients. There were no differences in radial or ulnar arterial diameters or velocities pre- and post-TRA in catheterization and non-catheterization hands (p = NS). The absolute total hand thermography values post-TRA were increased in both catheterization and non-catheterization hand (pre-TRA 30.4 ± 2.9 vs. post-TRA 31.6 ± 2.6 p < 0.01; pre-TRA 30.2 ± 2.9, post-TRA 31.6 ± 2.6 p < 0.01, respectively). After ulnar artery occlusion, hand temperatures decreased in both catheterization and non-catheterization hands, both pre- and post-TRA and were similar in the catheterization and non-catheterization hands (p = NS). Total hand temperature decreased with ulnar artery occlusion and was significantly attenuated post-TRA (p < 0.001 both catheterization and non-catheterization hands).

CONCLUSIONS

TRA is associated with temperature changes in both catheterization and non-catheterization hands at one month after the index procedure. These changes likely represent a systemic response to local TRA stimulus.

Transradial cerebral angiography: techniques and outcomes

Background

Despite several retrospective studies analyzing the safety and efficacy of transradial access (TRA) versus transfemoral access (TFA) for cerebral angiography, this transition for neurointerventional procedures has been gradual. Nonetheless, based on our positive initial institutional experience with TRA for mechanical thrombectomy in acute ischemic stroke patients, we have started transitioning more of our cerebral angiography cases to TRA. Here we present our single institution experience.

Methods

We performed a retrospective review of patients receiving TRA cerebral angiography at our institution between January 2016 and February 2017. We present our experience transitioning from TFA to TRA, including our criteria for patient selection, technical nuances, patient experience, complications, and operator learning curve.

Results

We included 148 angiograms performed in 141 people by one of four operators. No major complications were observed, and the technical success of the procedures was consistent with those of TFA. Marked improvement in operator efficiency was achieved in a short number of cases during this transition when looking at operator proficiency as a function of angiograms performed and days of exposure to TRA (4.3 vs 3.6 min/vessel, P<0.05).

Conclusions

Safety and efficiency can be preserved while transitioning to TRA. While further investigation is necessary to support transition to TRA, these findings should call for a re-evaluation of the role of TRA in catheter cerebral angiography.