Serpentine vs Traditional Hydrophilic Guidewire Tracking in Complex Radial Anatomy

Official title

Comparison of the "Serpentine" Technique Versus Hydrophilic Guidewire 0,035'' for Navigating Radial and Brachial Artery Loops, Tortuosity and Sharp Angulation During Transradial Access.

Overview

Coronary angiography and angioplasty are commonly performed through the radial artery. In some patients, anatomical variations of the radial and brachial arteries, such as loops, increased tortuosity or sharp angulations may pose challenges to equipment advancement. Both the hydrophilic guidewire 0,035'' approach and the "Serpentine" technique have been described in the literature as techniques for overcoming radial anatomical challenges, with the hydrophilic guidewire approach being the more commonly used method. In practical terms, both techniques involve the use of the same standard materials, with differences relating mainly to operator handling and technical manipulation. This study does not introduce any experimental device, material, or treatment; instead, it aims to compare the established approach using a 0.035'' hydrophilic guidewire with the emerging " Serpentine" technique with respect to effectiveness, procedural time, and safety.

Detailed description

Transradial access (TRA) has become the preferred approach for diagnostic coronary angiography and percutaneous coronary intervention (PCI), compared with transfemoral access (TFA). Contemporary guidelines on revascularization in both chronic and acute coronary syndromes (ACS) recommend TRA as the first-line strategy, primarily due to its reduced risk of complications.

Additional advantages of TRA include improved cost-effectiveness, shorter intensive care unit stay, shorter overall hospitalization, faster patient mobilization, and greater patient comfort. TRA has also been associated with reduced contrast use and a lower risk of contrast-induced acute kidney injury.

Despite its advantages, TRA has limitations. It is associated with a modest increase in radiation exposure. A key drawback is the need for crossover to another access site, which is relatively common; however, this can be mitigated by operator experience and ultrasound guidance.

Anatomical variants are a major cause of procedural failure and crossover, occurring in 9-23% of patients. The most frequent variants include high origin of the radial artery from the brachial artery, arterial loops, and tortuosity of the radial or subclavian artery. Radial artery loops and severe tortuosity, observed in 4.2-13,1% of cases, are strongly associated with procedural failure (3.8-50%) and increased crossover rates. These anatomical challenges prolong procedural time, increase radiation exposure, and raise the risk of vascular complication.

Several techniques have been proposed to overcome these challenges. The most commonly adopted is the use of hydrophilic guidewires. Other techniques include mechanical straightening of tortuous segments from the operator, the use of angioplasty guidewires, microcatheters, balloon-assisted tracking (BAT), pigtail-assisted tracking (PAT), or switching to ulnar, transfemoral, or contralateral radial access.

Preservation of the transradial approach is critical, as it reduces complications, facilitates faster mobilization, and shortens hospital stay. The most common cause of TRA failure is the presence of loops and tortuosity in the radial or brachial artery. To date, no randomized trials have directly compared different strategies for overcoming these challenges. The novel "Serpentine" technique, which will be compared against the widely used "0.035" hydrophilic guidewire, could become an additional tool for interventional cardiologists-providing a reliable method for crossing loops and tortuous segments, with reduced equipment use and comparable outcomes in terms of procedure time, radiation exposure, contrast use, and local complications.

The aim of this study is to compare the efficacy and safety of the novel "Serpentine" technique with that of hydrophilic guidewires in navigating radial and brachial artery loops and tortuosity during coronary angiography and PCI via TRA.

The S-TRACK Trial will be designed as a prospective, randomized, controlled, non-inferiority study. Consecutive eligible patients undergoing coronary angiography via transradial access, and not meeting any exclusion criteria, will be screened for enrollment. After successful radial artery cannulation, patients who demonstrate resistance to guidewire or catheter advancement will undergo radial and/or brachial angiography to identify the underlying anatomical cause. Participants with angiographically confirmed anatomical variants-specifically loops, pronounced tortuosity, or sharp angulations-will be considered eligible. Once the variant is confirmed, and oral consent provided, patients will be randomized in a 1:1 ratio to arterial navigation using either the standard hydrophilic 0.035'' guidewire-first technique or the Serpentine technique. At the end of the procedure informed consent will be signed. The study will involve operators-interventional cardiologists who will have been trained in the technique.

Baseline demographic, clinical, and laboratory parameters will be recorded, including age, sex, medical history, and indications for angiography. Additionally, the anatomical location of the loop or tortuosity will be recorded.

Interventions

• Procedure Serpentine Technique
  Catheter-based navigation technique using controlled rotational catheter manipulation to cross radial or brachial artery loops, tortuosity, or sharp angulation during transradial coronary angiography or PCI.
• Procedure Hydrophilic Technique
  Navigation of radial or brachial artery loops, tortuosity, or sharp angulation using a 0.035-inch hydrophilic guidewire during transradial coronary angiography or PCI.

Primary outcome measures

• Successful crossing of anatomical obstacles and procedure completion [Time frame: During coronary angiography/PCI procedure, assessed up to 3 hours]

Secondary outcome measures (10)

• Total procedure time [Time frame: During index procedure, assessed up to 3 hours.]
• Fluoroscopy time [Time frame: During index procedure, assessed up to 3 hours.]
• Radiation exposure [Time frame: During index procedure, assessed up to 3 hours.]
• Contrast volume used [Time frame: During index procedure, assessed up to 3 hours.]
• Success rate of loop access per technique [Time frame: During index procedure, assessed up to 3 hours.]
• Number of guidewires used [Time frame: During index procedure, assessed up to 3 hours.]
• Number of catheters used [Time frame: During index procedure, assessed up to 3 hours.]
• Radial artery spasm [Time frame: During index procedure, assessed up to 3 hours.]
• Procedure-related symptoms [Time frame: During index procedure, assessed up to 3 hours.]
• Access-site vascular complications [Time frame: From procedure completion until discharge, assessed up to 7 days]

Eligibility criteria

Inclusion criteria

• Age ≥18 years
• Feasibility of TRA
• Indication for coronary angiography
• Angiographic documentation of radial or brachial artery loop/tortuosity
• Written informed consent

Exclusion criteria

• STEMI - high risk NSTEMI presentation
• Hemodynamic instability
• Anatomical contraindications (e.g., arteriovenous fistula)
• Significant calcification of the radial or brachial artery on angiographic evaluation.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Treatment

Study locations

Greece · 1 center

• University Hospital of Patras — Pátrai

Publications

• Vrints C, Andreotti F, Koskinas KC, Rossello X, Adamo M, Ainslie J, Banning AP, Budaj A, Buechel RR, Chiariello GA, Chieffo A, Christodorescu RM, Deaton C, Doenst T, Jones HW, Kunadian V, Mehilli J, Milojevic M, Piek JJ, Pugliese F, Rubboli A, Semb AG, Senior R, Ten Berg JM, Van Belle E, Van Craenenbroeck EM, Vidal-Perez R, Winther S; ESC Scientific Document Group. 2024 ESC Guidelines for the mana PMID 39210710
• Byrne RA, Rossello X, Coughlan JJ, Barbato E, Berry C, Chieffo A, Claeys MJ, Dan GA, Dweck MR, Galbraith M, Gilard M, Hinterbuchner L, Jankowska EA, Juni P, Kimura T, Kunadian V, Leosdottir M, Lorusso R, Pedretti RFE, Rigopoulos AG, Rubini Gimenez M, Thiele H, Vranckx P, Wassmann S, Wenger NK, Ibanez B; ESC Scientific Document Group. 2023 ESC Guidelines for the management of acute coronary syndrom PMID 37622654
• Ferrante G, Rao SV, Juni P, Da Costa BR, Reimers B, Condorelli G, Anzuini A, Jolly SS, Bertrand OF, Krucoff MW, Windecker S, Valgimigli M. Radial Versus Femoral Access for Coronary Interventions Across the Entire Spectrum of Patients With Coronary Artery Disease: A Meta-Analysis of Randomized Trials. JACC Cardiovasc Interv. 2016 Jul 25;9(14):1419-34. doi: 10.1016/j.jcin.2016.04.014. Epub 2016 Jun PMID 27372195
• Meijers TA, Aminian A, van Wely M, Teeuwen K, Schmitz T, Dirksen MT, Rathore S, van der Schaaf RJ, Knaapen P, Dens J, Iglesias JF, Agostoni P, Roolvink V, Hermanides RS, van Royen N, van Leeuwen MAH. Randomized Comparison Between Radial and Femoral Large-Bore Access for Complex Percutaneous Coronary Intervention. JACC Cardiovasc Interv. 2021 Jun 28;14(12):1293-1303. doi: 10.1016/j.jcin.2021.03.041 PMID 34020929
• Jolly SS, Yusuf S, Cairns J, Niemela K, Xavier D, Widimsky P, Budaj A, Niemela M, Valentin V, Lewis BS, Avezum A, Steg PG, Rao SV, Gao P, Afzal R, Joyner CD, Chrolavicius S, Mehta SR; RIVAL trial group. Radial versus femoral access for coronary angiography and intervention in patients with acute coronary syndromes (RIVAL): a randomised, parallel group, multicentre trial. Lancet. 2011 Apr 23;377(97 PMID 21470671
• Valgimigli M, Gagnor A, Calabro P, Frigoli E, Leonardi S, Zaro T, Rubartelli P, Briguori C, Ando G, Repetto A, Limbruno U, Cortese B, Sganzerla P, Lupi A, Galli M, Colangelo S, Ierna S, Ausiello A, Presbitero P, Sardella G, Varbella F, Esposito G, Santarelli A, Tresoldi S, Nazzaro M, Zingarelli A, de Cesare N, Rigattieri S, Tosi P, Palmieri C, Brugaletta S, Rao SV, Heg D, Rothenbuhler M, Vranckx P PMID 25791214
• Amoroso G, Kiemeneij F. Transradial access for primary percutaneous coronary intervention: the next standard of care? Heart. 2010 Sep;96(17):1341-4. doi: 10.1136/hrt.2010.196824. PMID 20801852
• Mason PJ, Shah B, Tamis-Holland JE, Bittl JA, Cohen MG, Safirstein J, Drachman DE, Valle JA, Rhodes D, Gilchrist IC; American Heart Association Interventional Cardiovascular Care Committee of the Council on Clinical Cardiology; Council on Cardiovascular and Stroke Nursing; Council on Peripheral Vascular Disease; and Council on Genomic and Precision Medicine. An Update on Radial Artery Access and B PMID 30354598

Identifiers

NCT: NCT07707427 · 397/7-10-2025

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗