As More Peripheral Interventions Go Radial, the AHA Offers Some Insights

New advances are propelling a movement toward transradial access in the peripheral vascular intervention (PVI) space, but amid the optimism and potential benefits for patients there remain a number of hurdles before it becomes a preferred access route, according to a scientific statement from the American Heart Association.

The statement’s authors say they aimed to include information that is relevant for all members of vascular care teams, particularly in light of the increased interest in radial access for PVIs that is being driven by expansion of device options in the endovascular treatment of PAD, stroke, and elective embolization procedures.

Writing chair Jason C. Kovacic, MBBS, PhD (Icahn School of Medicine at Mount Sinai, New York, NY, and Victor Chang Cardiac Research Institute, Sydney, Australia), said with so much data for radial use in the coronary field, it’s no surprise that interventionalists are increasingly interested in applying the knowledge they’ve gained to their PVI procedures.

“What we know from the coronary field is radial access is patient preferred, it reduces bleeding complications, it’s safer, and in some contexts it can actually improve mortality and significant outcomes,” Kovacic said.

He and his coauthors say the paper comes at a time when radial considerations for PVI are at a stage of evolution comparable to where they were for coronary interventions between roughly 2005 and 2010.

Technology and Technique

Published online December 4, 2024, ahead of print in Circulation: Cardiovascular Interventions, the AHA document outlines a number of technical considerations when choosing radial access and anticipated benefits that would improve upon existing procedures and patient care.

Delving into the available literature, Kovacic and colleagues review anatomic location of the target lesion and lesion characteristics that are favorable to opting for a transradial approach as well as considerations for using a left or right access route.

Another important consideration when applying radial access in PVI is sheath sizes, which are often larger than what would be used in coronary procedures and can pose the potential for complications ranging from minor hematoma and radial artery spasm to artery perforation, hand ischemia, and compartment syndrome. The paper reviews known predictors of the more common complications as well as technical needs and preparation tips.

In neurovascular interventions, the writing group says the literature is evolving rapidly, particularly on the availability of smaller devices, including a sheathless balloon guide catheter for radial access in stroke thrombectomy cases.

Treatment of iatrogenic embolism is an area where the committee says research is needed to understand the optimal access site for minimizing covert brain infarcts on magnetic resonance diffusion-weighted imaging (DWI). Once considered insignificant, they are increasingly being recognized as contributors to adverse long-term outcomes. Whether radial access can reduce the risk of those compared with femoral access is an important consideration, according to Kovacic and colleagues.

Beyond the Peripheral

Additional endovascular procedures that are covered in the AHA paper include renal, mesenteric, uterine, and other arterial interventions in the abdomen or pelvis, with a discussion of advantages and disadvantages of femoral and radial access for each.

A section of the statement on lower limb interventions reviews what is known about radial versus femoral and pedal access in terms of technical success, complications, and radiation use. The authors note that in the TRIACCESS study, radial and pedal access were associated with fewer access-site complications than femoral access, while pedal access was associated with a reduction in radiation exposure.

Radiation is discussed several times in the document and is a significant consideration in peripheral procedures because compared with those done in the coronary, they can lend themselves to more radiation and longer exposure times due to the often complex nature of lesions in PAD and chronic limb-threatening ischemia.

But to TCTMD, Kovacic said radial access isn’t automatically associated with more radiation for operators.

“We mention in two places the option of feetfirst position for the patient (with radial access then potentially done via L arm in an abducted position)—this can reduce radiation exposure compared to a headfirst patient position,” he said in an email.

He also pointed to a caution from the AHA writing committee that additional clinical studies and randomized trials are needed to investigate the “various steps and indications of new techniques in transradial arterial access for PVI. The primary goal is to affirm the reduction of access site complications and shortened ambulation times compared with transfemoral arterial access. Enhanced radiation safety might be another aim.”

For care teams who don’t see a lot of radial access procedures for PVI, the paper suggests “brief refresher type cross-training on transradial arterial access and closure with the interventional cardiology team,” including physicians, nurses, technicians.

Finally, the committee concludes that it will be necessary to address practical challenges designing future studies that incorporate radial access in PVI.

“These include choosing the best outcome measure (eg, access-site complications, brain hits on DWI). Furthermore, study enrollment may become difficult, as the growing number of proceduralists who perform high volumes of transradial-arterial-access PVIs may be reluctant to randomize patients to [a transfemoral approach],” they write.