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

The important role of preoperative ultrasound in the efficacy and safety of coronary intervention via distal transradial access

BACKGROUND

The optimal inner diameter for enhancing the success rate of distal radial artery (DRA) puncture has not been documented. The aim of this study was to explore the appropriate inner diameter of DRA to increase the success rate of puncture and reduce vascular complications.

METHODS

This is a retrospective study. A receiver operating characteristic (ROC) curve was plotted to predict the DRA inner diameter for puncture success. The operative efficacy and safety were compared between groups with different DRA inner diameters, grouped according to the cut-off value.

RESULTS

A total of 670 patients were included in the study. The DRA inner diameter had a significant predictive value (AUC = 0.718) for puncture success, with a cut-off value of 1.95 mm. The puncture success rate was significantly lower in the DRA inner diameter < 2.0 mm group than in the DRA inner diameter ≥ 2.0 mm group (93.1% vs. 98.2%, P = 0.001). Twenty-five (3.7%) developed distal radial artery occlusion (dRAO) after the operation, including 15 dRAO without proximal radial artery occlusion (pRAO) and 10 dRAO with pRAO. The incidence of dRAO with pRAO was significantly greater in the DRA inner diameter < 2.0 mm subgroup than in the DRA inner diameter ≥ 2.0 mm subgroup (2.8% vs. 0.5%, P = 0.041).

CONCLUSIONS

The success rate of puncture was lower in patients with DRA inner diameter < 2.0 mm, whereas the incidence of dRAO with pRAO was higher.

CLINICAL TRIAL NUMBER

Not applicable.

Distal radial access to prevent radial artery occlusion for STEMI patients (RAPID III): a randomized controlled trial

BACKGROUND

Compared with conventional transradial access (TRA), distal radial access (DRA) is rarely used for percutaneous coronary intervention (PCI) in patients with ST-elevation myocardial infarction (STEMI) and may be beneficial to prevent radial artery occlusion (RAO). We aimed to evaluate the incidence of RAO between DRA and TRA 24 h after primary PCI in patients with STEMI.

METHODS

This is a single-center, open-label, prospective, randomized controlled trial conducted at Beijing Luhe Hospital, China, between January 2022 and July 2023. Five hundred and twenty patients (mean age: 61.3 ± 13.0 years; 81% male) with STEMI were randomly assigned to the DRA (n = 260) or TRA (n = 260) group. Primary PCI was performed using the radial artery access assigned study group. The primary endpoint was the rate of RAO assessed using Doppler ultrasound 24 h after primary PCI. Secondary outcomes included time taken for sheath insertion, access success rate, hemostasis time, fluoroscopy time, radiation dosage, and access-related complications.

RESULTS

The incidence of RAO was significantly lower in the DRA group than that in the TRA group (1.9% vs. 8.5%, P = 0.001). Access was successful in 94.6% of patients, and the crossover rate was 5.4% in both groups. The median time taken for sheath insertion was significantly longer (133 s vs. 114 s, P = 0.009), whereas the mean hemostasis time was shorter (209 ± 71 min vs. 372 ± 70 min, P < 0.001) in the DRA group. The incidence of modified Early Discharge After Transradial Stenting of Coronary Arteries (mEASY) ≥ II hematoma was lower in the DRA group (0.8% vs. 3.5%, P = 0.033). However, there was no significant difference in fluoroscopy time, radiation dosage, or access-related complications.

CONCLUSIONS

In patients with STEMI undergoing primary PCI, compared with TRA, DRA prevented RAO 24 h postoperatively and was associated with shorter hemostasis time and a lower incidence of mEASY ≥ II hematoma.

TRIAL REGISTRATION

Clinical Trials.gov Identifier: NCT05461781.

[Distal radial access for coronary procedures in an all-comer population: the first 1000 patients in a prospective cohort]

Introduction and objectives

Distal radial access (DRA) for coronary procedures is currently recognized as an alternative to conventional transradial access, with documented advantages primarily related to access-related complications. However, widespread adoption of DRA as the default approach remains limited. Therefore, this prospective cohort study aimed to present our initial experience with DRA for coronary procedures in any clinical settings.

Methods

From August 2020 to November 2023, we included 1000 DRA procedures (943 patients) conducted at a single center. The study enrolled a diverse patient population. We recommended pre- and postprocedural ultrasound evaluations of the radial artery course, with ultrasound-guided DRA puncture. The primary endpoint was DRA success, while secondary endpoints included coronary procedure success, DRA performance metrics, and the incidence of access-related complications.

Results

The DRA success rate was 97.4% (n = 974), with coronary procedure success at 96.9% (n = 969). The median DRA time was 40 [interquartile range, 30-60] seconds. Diagnostic procedures accounted for 64% (n = 644) of cases, while 36% (n = 356) involved percutaneous coronary intervention (PCI), including primary PCI in 13% (n = 128). Pre-procedure ultrasound evaluation and ultrasound-guided DRA were performed in 83% (n = 830) and 85% (n = 848) of cases, respectively. Access-related complications occurred in 2.9% (n = 29).

Conclusions

This study shows the safety and feasibility of DRA for coronary procedures, particularly when performed under ultrasound guidance in a diverse patient population. High rates of successful access and coronary procedure outcomes were observed, together with a low incidence of access-related complications. The study was registered on ClinicalTrials.gov (NTC06165406).

Distal versus proximal radial access in coronary angiography: a meta-analysis

BACKGROUND

Distal radial access (DRA) represents a promising alternative to conventional proximal radial access (PRA) for coronary angiography. Substantial advantages regarding safety and efficacy have been suggested for DRA, but the ideal access route remains controversial.

AIMS

The aim of this study was to compare safety, efficacy and feasibility of DRA to PRA.

METHODS

National Library of Medicine PubMed, Web of Science, clinicaltrials.gov and Cochrane Library were systematically searched for randomized controlled trials and registry studies comparing DRA and PRA that were published between January 1, 2017 and April, 2024. Primary endpoint was the rate of radial artery occlusion (RAO). Secondary endpoints were access failure, access time, procedure time, arterial spasm, hematoma, and hemostasis time. Data extraction was performed by two independent investigators. Relative risks were aggregated using a random effects model. We applied meta-analytic regression to assess study characteristic variables as possible moderators of the study effects.

RESULTS

44 studies with a total of 21,081 patients were included. We found a significantly lower rate of RAO after DRA (DRA 1.28%, PRA 4.76%, p < .001) with a 2.92 times lower risk compared to the proximal approach (Log Risk Ratio = -1.07, p < .001). Conversely, the risk for access failure was 2.42 times higher for DRA compared to PRA (Log Risk Ratio = 0.88, p < .001).

CONCLUSION

In this largest meta-analysis to date, we were able to show that rates of RAO are reduced with DRA compared to conventional PRA. This suggests DRA is a safe alternative to PRA.

The distal radial artery: Versatile vascular access for transcatheter interventions

Conventional transradial access has been established as the gold standard for invasive coronary angiography and percutaneous interventions by the current European and American guidelines. The distal or snuffbox radial artery access represents an alternative transradial access site that allows radial sheath insertion with the patient's hand pronated. Firstly described 40 years ago, it exploded in popularity only recently. Promising additional benefits, the distal radial access is increasingly being adopted in various types of percutaneous interventions, being preferred by many interventional cardiologists and radiologists for its reduced vascular complications and time to hemostasis, and improvement of patient and operator comfort. Other centers consider it a fad, waiting for solid clear evidence and benefits. The evidence is dynamic and discrepant, depending on the center, the operator, and how it was collected (randomized controlled vs observational studies). Another essential aspect raised by "skeptics" was whether distal radial access, by its smaller diameter and more angled course, can support all types of interventions. The aim of this review is to gather all the scenarios where distal radial access has been utilized and to conclude whether this vascular access is feasible across all transcatheter interventions.

Distal Radial Access for Coronary Procedures in a Large Prospective Multicenter Registry: The KODRA Trial

BACKGROUND

Distal radial access (DRA) as an alternative access route lacks evidence, despite its recent reputation.

OBJECTIVES

The aim of this study was to evaluate the safety and feasibility of DRA on the basis of daily practice.

METHODS

The KODRA (Korean Prospective Registry for Evaluating the Safety and Efficacy of Distal Radial Approach) trial was a prospective multicenter registry conducted at 14 hospitals between September 2019 and September 2021. The primary endpoints were the success rates of coronary angiography (CAG) and percutaneous coronary intervention (PCI). The secondary endpoints included successful distal radial artery puncture, access-site crossover, access site-related complications, bleeding events, and predictors of puncture failure.

RESULTS

A total of 4,977 among 5,712 screened patients were recruited after the exclusion of 735 patients. The primary endpoints, the success rates of CAG and PCI via DRA, were 100% and 98.8%, respectively, among successful punctures of the distal radial artery (94.4%). Access-site crossover occurred in 333 patients (6.7%). The rates of distal radial artery occlusion and radial artery occlusion by palpation were 0.8% (36 of 4,340) and 0.8% (33 of 4,340) at 1-month follow-up. DRA-related bleeding events were observed in 3.3% of patients, without serious hematoma. Multilevel logistic regression analysis identified weak pulse (OR: 9.994; 95% CI: 7.252-13.774) and DRA experience <100 cases (OR: 2.187; 95% CI: 1.383-3.456) as predictors of puncture failure.

CONCLUSIONS

In this large-scale prospective multicenter registry, DRA demonstrated high success rates of CAG and PCI, with a high rate of puncture success but low rates of distal radial artery occlusion, radial artery occlusion, bleeding events, and procedure-related complications. Weak pulse and DRA experience <100 cases were predictors of puncture failure. (Korean Prospective Registry for Evaluating the Safety and Efficacy of Distal Radial Approach [KODRA]; NCT04080700).

Distal Versus Proximal Radial Artery Access for Cardiac Catheterization: 30-Day Outcomes of the DIPRA Study

Background Proximal radial artery (pRA) access for cardiac catheterization is safe but can jeopardize subsequent use of the artery because of occlusion. Distal radial artery (dRA) access in the anatomical snuffbox preserves the radial artery, but safety and potential detrimental effects on hand function are unknown. Methods and Results In the DIPRA (Distal Versus Proximal Radial Artery Access for Cardiac Catheterization and Intervention) study, a single-center trial, 300 patients were randomized 1:1 to cardiac catheterization through dRA or pRA. The primary end point of change in hand function from baseline to 30 days was a composite of the QuickDASH (Quick Disabilities of the Arm, Shoulder and Hand) questionnaire, hand-grip test, and thumb forefinger pinch test. Secondary end points included access feasibility and complications; 254 of 300 patients completed follow-up at 30 days; of these, 128 were randomized to dRA and 126 to pRA with balanced demographic and procedural characteristics. Both groups had similar rates of access site bleeding (dRA 0% versus pRA 1.4%; P=0.25). Six patients with dRA failed access compared with 2 patients with pRA. Radial artery occlusion occurred in 2 pRA versus none in dRA. There were no significant differences in change in hand function, median hand-grip (dRA 0 [-3.2, 3.3] versus pRA 0.7 [-2.3, 3.3] kg; P=0.21), pinch-grip (dRA -0.3 [-1.2, 0.5] versus pRA 0 [-0.9, 0.9] kg; P=0.09), and QuickDASH (dRA 0 [-4.6, 2.3] versus pRA 0 [-4.6, 2.3] points, P=0.96). There was no significant difference in the composite of hand function between pRA and dRA. Conclusions dRA is a safe strategy for cardiac catheterization with a low complication rate. Compared with pRA, there is no increased risk of hand dysfunction at 30 days. Registration URL: https://www.ClinicalTrials.gov. Unique identifier: NCT04318990.

Distal Radial Approach in Coronary Angiography Using a Transdermal Nitroglycerin Patch: Double-Blinded Randomized Trial

Nitroglycerin dilates the radial artery and prevents spasm, which increases the success rate of sheath cannulation through the conventional transradial approach. However, the effects of nitroglycerin on distal radial approach (DRA) procedures are not known. The aim of this study is to elucidate whether a transdermal nitroglycerin patch improves the rate of successful DRA cannulation. A total of 92 patients scheduled for coronary angiography by means of DRA randomly received (1:1) a transdermal nitroglycerin patch preintegrated with the covering material or only the covering material on their upper arm on the side of the puncture. The diameter of the distal radial artery was evaluated with ultrasound at baseline and after application. DRA procedures were performed in a double-blind fashion. The primary outcome was the rate of successful palpation-guided distal radial artery cannulation with the first puncture. The nitroglycerin group had larger distal radial artery diameter after patch application than that of the no-treatment group (mean, 3.21 mm vs 2.71 mm, p <0.001), but not at baseline (mean, 2.64 mm vs 2.64 mm, p = 0.965).The nitroglycerin group had a significantly higher success rate of DRA cannulation with the first puncture than that of the no-treatment group (59% vs 24%, p = 0.001; odds ratio 4.5, 95% confidence interval 1.9 to 11.0). The nitroglycerin group required fewer punctures than did the no-treatment group (median, 1 vs 3, p = 0.019). There were no significant differences in the occurrence of hypotension between the 2 groups. No patients experienced radial artery occlusion. In conclusion, transdermal nitroglycerin patch application safely facilitates DRA cannulation. Trial Registration: Japan Registry of Clinical Trials, https://jrct.niph.go.jp/ (identifier: jRCTs051210128).

Comparison of spasmolytic regimen for prevention of radial artery spasm during the distal radial approach: A single-center, randomized study

Background

The distal radial approach (DRA) for coronary catheterization is increasingly being used worldwide yet the optimal medication regimen to prevent radial artery spasm (RAS), an important factor for the success of the procedure, remains unclear. The aim of this study is to examine the effectiveness of medication for preventing RAS via the DRA.

Methods

This was a prospective, comparative randomized study including 400 patients who underwent coronary catheterization via DRA in single center by three experienced DRA operators. Patients were randomized to either nitroglycerin (NTG) injection (N = 200) or NTG plus verapamil (N = 200) to compare the effectiveness and safety of these regimens.

Results

There were no differences between the groups in the changes in radial artery diameter at most spastic area (0.34 ± 0.20 in the NTG group, 0.35 ± 0.20 in the NTG plus verapamil group; P = 0.73). There was no difference between the groups in the ratio of patients without arm pain during the procedure (95.0% in the NTG group, 93.5% in the NTG plus verapamil group; P = 0.67). However, there was a greater reduction in diastolic blood pressure in the NTG plus verapamil group (-8.3 ± 7.9 mmHg) than in the NTG group (-6.6 ± 7.6 mmHg) (P = 0.03).

Conclusion

Intra-arterial injection of NTG as a single agent is effective and safe in the prevention of RAS during coronary catheterization via the DRA compared with a cocktail regimen of NTG plus verapamil.

Clinical trial registration

https://cris.nih.go.kr, identifier KCT0005177.

The Role of Ultrasound in Accessing the Distal Radial Artery at the Anatomical Snuffbox for Cardiovascular Interventions

In an effort to refine transcatheter vascular interventions, radial artery access has moved more distally at the anatomical snuffbox. Here, more challenges appear as the artery is smaller, more angulated, and more difficult to palpate. Including ultrasound guidance as a mandatory step during puncture may encourage more operators to switch to this approach. In the femoral approach, ultrasound guidance is strongly recommended because of bleeding complications, whereas in the proximal (conventional) radial approach, the role of ultrasound remains optional, and in current practice, almost all cases are performed by palpation of the pulse only. However, in distal radial access, the situation is different because the artery differs in caliber and position, and imaging can help the operator for a clean puncture, especially since repeated punctures are not only painful but also any hematoma formation leads to the complete compression of the artery and failure of access. The aim of this review is to investigate the rationale of vascular ultrasound during distal radial access and to establish some techniques and anatomical landmarks for the ultrasonographic exploration of the dorsal area of the hand.

Distal Radial Artery Access for Recanalization of Radial Artery Occlusion and Repeat Intervention: A Single Center Experience

Background: Once occluded, the radial artery becomes unsuitable for repeat interventions and obligates the need for alternative vascular access, such as the femoral approach, which is not encouraged by current guidelines. With the dissemination of distal radial access (DRA), which allows the cannulation of the artery in its distal segment and which remains patent even in the case of radial artery occlusion (RAO), the option to perform angioplasty at this level becomes feasible. Methods: Thirty patients with RAO were enrolled in this pilot study. Recanalization was performed through DRA using hydrophilic guidewires. The feasibility endpoint was procedural success, namely the successful RAO recanalization, the efficacy endpoint was patency of the artery at 30 days, and the safety endpoint was the absence of periprocedural vascular major complications or major adverse cardiac and cerebrovascular events. Results: The mean age of the patients was 63 ± 11 years, and 15 patients (50%) were men. Most patients had asymptomatic RAO (n = 28, 93.3%), and only two (6.6%) reported numbness in their hands. The most common indication for the procedure was PCI (19, 63.2%). Total procedural time was 41 ± 22 min, while the amount of contrast used was 140 ± 28 mL. Procedural success was 100% (n = 30). Moreover, there were no major vascular complications (0%); only two small hematomas were described (10%) and one had an angiographically visible perforation (3%). One case of periprocedural stroke was reported (3%), with onset immediately after the procedure and recovering 24 h later. Twenty-seven radial arteries (90%) remained patent at the one-month follow-up. Conclusions: RAO recanalization is feasible and safe, and by using dedicated hydrophilic guidewires, the success rate is high without significantly increasing procedural time or the amount of used contrast.