A Call for Comprehensive Forearm Access?
The radial approach for coronary angiography has several recognized advantages over transfemoral angiography, particularly less bleeding and fewer access-site complications.1,2 In addition, a reduction in mortality with the transradial approach in patients presenting with an acute coronary syndrome has been suggested in multiple clinical trials.3-5 This has led to a significant shift in consensus statements recommending transradial angiography (TRA) for cases of ST-elevation myocardial infarction (ie, those at the highest risk of bleeding), and most recently the European Society of Cardiology guideline statement for managing non-ST elevation acute coronary syndromes gives a class IA recommendation to TRA for centers experienced in radial access. The potential for transradial interventions to reduce all-cause mortality has mechanistically been attributed to a decrease in major bleeding. Therefore, it stands to reason that transulnar angiography (TUA) could have similar advantages, and offer yet another option instead of a transfemoral approach.
In this issue of the Journal of Invasive Cardiology, Gokhroo et al present an interesting single-center study in which six operators with extensive experience in both transradial and transulnar cannulation randomized 2532 patients to either TRA or TUA to determine non-inferiority of the TUA with a margin of error of 4.87%.6 This work was first presented as featured clinical research at the American College of Cardiology 2015 Annual Scientific Sessions. Nearly 50% of patients enrolled in this trial had ST-elevation myocardial infarction and another 30% presented with non-ST elevation myocardial infarction. Angiography was performed with 5 Fr arterial sheaths that were upsized to 6 Fr sheaths for percutaneous coronary intervention, which was performed with heparin and a provisional glycoprotein IIb/IIIa inhibitor at the operator’s discretion. Arterial vasospasm was prophylactically managed with a cocktail of nitroglycerin, diltiazem, and lidocaine and could be administered again during the case at the operator’s discretion. Access-site hemostasis was accomplished with an arterial band at the puncture site for 5 hours. The primary outcome was a composite of death, myocardial infarction, stroke, urgent target-vessel revascularization, access-site crossover, and major vascular events during the hospitalization as determined by the operators. Arterial patency and ulnar nerve injury were identified by detailed examination in follow-up at 1 week.
Similar to earlier clinical trials of TRA, the authors identified a learning curve with TUA.7 If operators were unable to obtain access in the initially allocated artery, they were instructed to crossover to the same artery in the contralateral arm. If access was still unsuccessful, they would attempt the other forearm artery before finally crossing over to the femoral artery. Not unexpectedly, when the operators performed under 50 transulnar cannulations, they encountered high rates of large hematomas, spasm, longer puncture times, and a crossover rate as high as 16%. After performing 100 cannulations, the crossover rate for TUA was only 5%, which is comparable to TRA. The need for high procedural volumes to reduce access-site complications in the forearm is a recurring theme that is particularly relevant for TUA because of the deeper course of the ulnar artery in the forearm compared with the more superficial radial artery. Appropriate patient selection is also an important factor to consider. Patients were excluded from the current study if the patient had coronary artery bypass grafts, or if the operator was unable to palpate either artery or was unable to cannulate the assigned artery within three attempts. With operator experience and thoughtful patient selection, the authors were able to achieve right forearm access in 95% of patients and only 5 total cases crossed over to femoral access. It is also worth noting that the average access time was approximately 6 minutes in both cohorts.
The authors demonstrated the non-inferiority of TUA with a composite primary outcome occurring in 14.6% of patients with TUA and 14.4% of patients with TRA. The individual components of major adverse cardiovascular events, large hematomas, arterial occlusions, and crossover rates did not have any significant between-group differences. The outcomes were limited to the index hospitalization though, and the potential for bias through self-reporting cannot be overlooked. However, it is encouraging to see that there was no difference in access-site bleeding or vessel patency rates in follow-up. There were 12 cases of local parasthesia and 5 cases of local neurological deficit isolated to TUA, but these were reported as transient and self-limited in nature. If the advantages of TRA over transfemoral angiography are driven by a reduction in major bleeding, and if similar bleeding rates can be achieved with TUA without additional adverse events, it is exciting to consider yet another revolution in our approach to coronary angiography.
A few more words of caution are necessary before applying the results of this study to daily practice. If an operator attempts radial access and is unsuccessful, moving to ulnar access on that same side would be very efficient. Before such a strategy is routinely embraced, more data are needed about the safety of potentially compromising both radial and ulnar circulation to the hand, if a complication were to occur. Initial experiences with this approach show that it appears to be safe; however, more data are needed.8 Additionally, the ulnar artery is typically deeper and hemostasis is not quite as easy to achieve as with the radial artery. Therefore, protocols for length and intensity of arterial compression band application are needed to ensure that high rates of ulnar (or radial) compromise are not occurring.
Furthermore, as the authors recognize, this is a single-center study conducted by six high-volume operators and all outcomes were self-reported. Episodes of arterial occlusion and nerve injury were determined on examination without objective testing. There is likely a steep learning curve for transulnar access, even for experienced radial operators, and certainly for femoral operators adopting a forearm-first approach. Yet by performing TUA with a high degree of success and demonstrating non-inferiority to TRA, this study should certainly prompt larger multicenter clinical trials in TUA. Transfemoral angiography is no longer the predominant technique in a growing number of centers around the world. TUA holds the promise of an additional non-femoral vascular access route, keeping in mind that operator experience and patient selection are key elements to adopting a comprehensive forearm approach.
References
1. Feldman DN, Swaminathan RV, Kaltenbach LA, et al. Adoption of radial access and comparison of outcomes to femoral access in percutaneous coronary intervention: an updated report from the National Cardiovascular Data Registry (2007-2012). Circulation. 2013;127:2295-2306.
2. Gutierrez JA, Harrington RA, Blankenship JC, et al. The effect of cangrelor and access site on ischaemic and bleeding events: insights from CHAMPION PHOENIX. Eur Heart J. 2015 Sep 23 (Epub ahead of print).
3. Valgimigli M, Gagnor A, Calabró P, et al. Radial versus femoral access in patients with acute coronary syndromes undergoing invasive management: a randomised multicentre trial. Lancet. 2015;385:2465-2476.
4. Jolly SS, Yusuf S, Caims J, et al. Radial versus femoral access for coronary angiography and intervention in patients with acute coronary syndromes (RIVAL): a randomised, parallel group, multicentre trial. Lancet. 2011;377:1409-1420.
5. Romagnoli E, Biondi-Zoccai G, Sciahbasi A, et al. Radial versus femoral randomized investigation in ST-segment elevation acute coronary syndrome: the RIFLE-STEACS (Radial Versus Femoral Randomized Investigation in ST-Elevation Acute Coronary Syndrome) study. J Am Coll Cardiol. 2012;60:2481-2489.
6. Gokhroo R, Kishor K, Bhanwar R, Bisht D, Gupta S, Avinash A. Ulnar artery interventions non inferior to radial approach: Ajmer Ulnar Artery (AJULAR) intervention working group study results. J Invasive Cardiol. 2016;28:1-8.
7. Gutierrez A, Tsai TT, Stanislawski MA, et al. Adoption of transradial percutaneous coronary intervention and outcomes according to center radial volume in the Veterans Affairs Healthcare System: insights from the Veterans Affairs Clinical Assessment, Reporting, and Tracking (CART) Program. Circ Cardiovasc Interv. 2013;6:336-346.
8. Kedev S, Zafirovska B, Dharma S, Petkoska D. Safety and feasibility of transulnar catheterization when ipsilateral radial access is not available. Catheter Cardiovasc Interv. 2014;83:E51-E60.
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From 1Brigham and Women’s Hospital Heart & Vascular Center and Harvard Medical School, Boston, Massachusetts; and 2Duke Clinical Research Institute, Durham, North Carolina.
Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Sawlani reports no relevant disclosures. Dr Rao reports consultant fees from Medtronic and Terumo Interventional Systems, Inc. Dr Bhatt is the Editor-in-Chief of the Journal of Invasive Cardiology and reports the following disclosures: Advisory board: Cardax, Elsevier Practice Update Cardiology, Medscape Cardiology, Regado Biosciences; Board of Directors: Boston VA Research Institute, Society of Cardiovascular Patient Care; Chair: American Heart Association Quality Oversight Committee; Data monitoring committees: Duke Clinical Research Institute, Harvard Clinical Research Institute, Mayo Clinic, Population Health Research Institute; Honoraria: American College of Cardiology (Senior Associate Editor, Clinical Trials and News, ACC.org), Belvoir Publications (Editor-in-Chief, Harvard Heart Letter), Duke Clinical Research Institute (clinical trial steering committees), Harvard Clinical Research Institute (clinical trial steering committee), Journal of the American College of Cardiology (Guest Editor; Associate Editor), Population Health Research Institute (clinical trial steering committee), Slack Publications (Chief Medical Editor, Cardiology Today’s Intervention), Society of Cardiovascular Patient Care (Secretary/Treasurer), WebMD (CME steering committees); Other: Clinical Cardiology (Deputy Editor); Research funding: Amarin, AstraZeneca, Bristol-Myers Squibb, Eisai, Ethicon, Forest Laboratories, Ischemix, Medtronic, Pfizer, Roche, Sanofi Aventis, The Medicines Company; Royalties: Elsevier (Editor, Cardiovascular Intervention: A Companion to Braunwald’s Heart Disease); Site co-investigator: Biotronik, St. Jude Medical; Trustee: American College of Cardiology; Unfunded research: FlowCo, PLx Pharma, Takeda.
Address for correspondence: Deepak L. Bhatt, MD, MPH, Brigham and Women’s Hospital Heart & Vascular Center and Harvard Medical School, 75 Francis Street, Boston, MA 02115. Email: dlbhattmd@post.harvard.edu
