Top 10 Tricks for Transradial Procedures
As transradial access becomes more accepted by interventional proceduralists, one expert gives his tips as to how fellows can best learn this technique.
Robert W. Yeh, MD, MBA, director of the Smith Center for Outcomes Research at Beth Israel Deaconess Medical Center (Boston, MA), is an interventional cardiologist who specializes in clinical research and complex coronary interventions. He sat down with TCTMD’s Fellows Forum to discuss his Top 10 Tricks for fellows interested in performing procedures via radial access.
1. Learn the facts
Many trials have indicated that transradial catheterization is strongly preferred by patients over femoral access, because it is more comfortable and it lets them ambulate more quickly. But most importantly, it reduces bleeding and vascular access complications. For certain populations, like STEMI patients, research has also shown increased survival rates with radial use. (Yeh recommends reviewing the results of RIVAL, RIFLE-STEACS, and MATRIX). Radial access is also more cost-effective, because patients have shorter lengths of stay and it can help to support same-day discharge programs.
2. Identify the right patients
When first learning how to perform radial procedures, inexperienced operators may want to steer clear of patients with complex PCI, CABG patients, the elderly, and shorter women—as gaining access and engaging the coronaries can be difficult in these groups, Yeh says. Instead, consider starting with lower-complexity diagnostic cases. As you get more comfortable and successful with radial, “the most important thing is to pick the patients who will benefit the most.” That means progressively increasing the complexity of the patients who you take on radially and being comfortable with STEMI patients in particular. While definitive evidence shows that mortality and hard endpoints are improved with radial in this population, physicians are also the most reluctant to take these time-dependent cases on due to the higher stress of needing to be fast. But that is exactly the opposite of what we should be doing, Yeh advises. “Interventionalists should be gradually evolving to the point where they feel comfortable with performing radial procedures on STEMI patients or other complicated patients at high risk for bleeding complications.”
3. Have a consistent set-up
As with most things in medicine, you should create consistency in the way your team performs radial procedures. There needs to be protocol for techs and nurses, and everyone must understand the right set-up, Yeh says. Many labs transitioning from femoral to radial access keep everything the same apart from prepping the patients’ wrists. But there are actually some specific things that can improve ergonomics and make things easier for the operator. Yeh suggests setting up a platform next to the patient’s right leg as an extension of the patient’s wrist to avoid doing things “in the air.” That way, you have a tabletop surface to work on. Also, when using a left radial, you may wish to use finger traps to pull the left hand over to stabilize it securely. But whatever set-up you decide upon, stick with it each time and make sure your team knows what it is.
4. Choose an access method
There are 2 methods for gaining access to the radial artery—front wall stick with a micropuncture needle or using an angiocath with a through-and-through technique followed by a pullback. Yeh strongly prefers the latter as he believes it is more forgiving, while the former requires more precise maneuvering. The through-and-through technique also allows for time to reset before pulling the catheter back until seeing blood flow, he adds. Also, “when you are pulling back and you see flow, generally the lumen of the angiocath flows better than the micropuncture needle, and so I feel more confident of a good midluminal stick.” Again, whichever you find is more comfortable for you, be consistent with every procedure.
5. Wait for pulsatile flow
Never wire a vessel that you are not sure has very good flow, Yeh says. Particularly with the through-and-through using an angiocath technique, you may be tempted to wire the vessel at the first sign of flow, but “that’s almost never the right time,” he explains. Yeh often sees fellows try to do this and then end up jamming in the wire, but this can lead to dissection of the artery. Instead, he recommends waiting until the lumen is big enough to show pulsatile flow. “I’m perfectly happy to pull it all the way out of the vessel and have to redo it again, rather than have a wire get into a false lumen and lead to radial spasm,” Yeh comments.
6. Choose a Supportive Guide Catheter
Another temptation with transradial procedures, especially from the right side, he says, is to use shorter guides like the XB3, CLS3, or 3-series of guides, just because they are easier to initially engage the left coronary with. “You will often end up regretting that you chose it later in the case because they provide much less support,” Yeh explains, adding that he always tells fellows to start with a regular length guide—usually an EBU3.5 or an XB3.5.
7. Use the patient’s breathing to your advantage
Before the guide is engaged, Yeh recommends using the fact that the patient is awake to your benefit. Specifically, it can be hard to navigate around a tortuous subclavian and gain access into the ascending aorta. To enable your catheters to rotate, have the patient take a deep breath. That should straighten out the tortuosity of the vessel. Do not be afraid to ask patients to do this frequently, as it will only help you as you try to navigate to get into the coronaries, he says.
8. Master complex PCI scenarios with the same guide size
“It turns out that you can do almost anything through [a] 6-Fr [catheter],” Yeh observes. This includes left main bifurcation stenting, rotational atherectomy, laser atherectomy, and some CTO interventions. While this is commonly known, “sometimes people forget,” he notes. On the occasion you do in fact need to choose a bigger guide catheter, remember that options exist for allowing larger equipment, like sheathless large-caliber guide catheters that can accommodate up to 7.5- or 8-Fr. The use of guide-extension catheters also helps to overcome some of the limitations of guide support that may frequently be encountered in radial procedures.
9. Achieve hemostasis with patency
Remembering this key step—achieving hemostasis with patency—will help improve long-term outcomes. However, “if you’re too tight with your hemostasis device [or] you put it on too long, you could end up having radial artery occlusion,” Yeh warns. “There’s good evidence that we can reduce that risk of radial artery occlusion by making sure we have patent hemostasis, [that is] we still have pulsatile flow through the radial artery as assessed by plethysmography despite application of a hemostatic device.” Another way to ensure adequate patency is always anticoagulating every case, even diagnostic ones, he adds. Dr. Yeh recommends reading a set of guidelines set forth by the Society for Cardiovascular Angiography and Interventions for radial catheterization best practices.
10. Be enthusiastic, especially when starting a program
Going back to tip number 1—the first thing you need to do when starting a radial program at an institution is to have the group review the literature supporting the need for transradial access. “Everybody needs to understand why radial is important before you can get a team to start changing the way they do things,” Yeh says. Then it is all about your enthusiasm and willingness to support the transition. “Almost all changes to clinical practice in hospitals, are going to live or die by the physician champion and how well they are able to engage the staff to make sure everyone views this as a team goal,” he comments, adding that the best way to do this is to solicit feedback, learn from the people who have come before you, and be both passionate and respectful.
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