Bailout no more: Transradial PCI goes mainstream, but the US lags behind

August 20, 2009

Toronto , ON - Transradial PCI makes for sensational television and newspaper stories: "Treating heart disease through the wrist!" But despite recent data showing significantly fewer bleeding complications and equivalent procedural success, plus a growing number of proponents championing the approach, the radial technique is often as foreign to doctors as it is to patients, at least in the US.

 
The fact is we're taught what our institutions are doing, and we might not be exposed to certain things because our teachers don't do them.
 

As a young cardiologist who completed her fellowship in interventional cardiology in 2005, Dr Jennifer Tremmel (Stanford University, CA) says she went through her fellowship training "without hearing about radials at all." Tremmel told heart wire : "I remember somebody once giving me an article about it, and that was the extent of it. I had no exposure to radial interventions. The fact is we're taught what our institutions are doing, and we might not be exposed to certain things because our teachers don't do them."

Dr Jennifer Tremmel

And it's true, not a lot of US interventional cardiologists are using the wrist to access the heart, instead opting for the traditional femoral route, an approach they were trained in and continue to practice. Recent estimates, according to a study that looked at trends in the prevalence of radial-access PCI using data from the National Cardiovascular Data Registry (NCDR), show the approach to be extremely rare in contemporary practice[1]. Of nearly 600 000 first PCI procedures performed from 2004 to 2007, just 1.32% were done through the radial artery.

This low rate of adoption is primarily limited to the US, however, with other countries, including Canada, more likely to employ radial-artery catheterization. Dr Olivier Bertrand (Laval University, Quebec, QC) told heart wire that his institution began its radial program in 1994 and since then has treated more than 70 000 patients by radial access, making it one of the most experienced, high-volume centers using the radial approach.

Dr Olivier Bertrand

"I am strongly convinced that radial access should be the default technique, the preferred technique, for all patients," said Bertrand. "If you take the perspective of the patient, there is basically no reason to continue to do femoral-access PCI. What I usually say is that if I had to take a blood sample and I gave my patients the choice between using a jugular vein in the neck or a small vein in the arm, nobody would choose the great vein in the neck. This is what physicians don't always understand, and mostly because of habit and by previous training, they continue to use the femoral artery for PCI."

Bertrand said that in many European countries, including France, Italy, and Spain, the radial route plays a more dominant role, while nearly 50% of cases are done radially in Canada. In Norway, almost 90% of cases are transradial interventions, while in China roughly 80% of interventional procedures are done through the wrist.

"The only people still reluctant to change are the US guys," he said. "I can tell you that there is momentum for change, and the timing is right."

Tide turning in US, but rates still low

New data in the past decade continue to show that the transradial technique is associated with a significantly lower rate of complications, particularly access-site bleeding, than femoral PCI. A large meta-analysis by Dr Sanjit Jolly (McMaster University, Hamilton, ON) and colleagues, first presented at the Canadian Cardiovascular Congress and reported by heartwire at that time, as well as published in the American Heart Journal, showed that radial-access PCI reduced the risk of major bleeding 73% compared with the femoral approach[2].

Similar analyses in different patient populations are also showing positive results. A study presented last January at the International Symposium of Endovascular Therapy showed that the technique can be done successfully in complex PCI cases, including patients with acute MI, chronic total occlusions, and bifurcated lesions. The investigators noted that procedural success rates were as high as 98.5% in patients with complex lesions and nearly 80% in patients with chronic total occlusions. Bleeding rates also remained low.

"I actually feel a sense of guilt when I go through the femoral artery," said Tremmel. "It's hard for me to do a femoral procedure because I know I'm putting that person at a higher risk of a bleeding complication when I don't need to. It's a very surprising feeling, going to groin and feeling bad about this."

Moreover, bleeding is not simply an innocuous complication. Studies suggest, including a trend in the meta-analysis by Jolly and colleagues, that bleeding is associated with worse clinical outcomes. Speaking with heart wire , Tremmel, who also serves as the clinical director of women's health at Stanford University, said that women are at a two- to three-times higher risk of bleeding than men, including a higher risk of retroperitoneal hematomas, and that she had previously looked for ways to improve outcomes of women so that they matched those of men.

 
I actually feel a sense of guilt when I go through the femoral artery.
 

"I just happened to see an article on the risk of bleeding with the femoral and radial approaches, and there was a significant reduction in bleeding with the radial approach in both sexes, but it was even more significant for women because they had a higher baseline risk," she said. "I had one of those 'Aha!' moments where I thought, I have to learn how to do this."

The interventional community has become complacent about bleeding, she added, with most accepting that PCI carries a risk and, because bleeding rates aren't "super high," are not moved to do something about it. Since learning the technique over one-and-a-half days at an industry-funded course in New York City, she has steadily increased the percentage of cases where she attempts the radial approach first. Now doing almost 100% of her cases via the radial artery, and with a procedural success rate close to 100%, Tremmel said that other clinicians in her lab have watched her work and now do some cases with radial-arterial access. She added that she takes on all-comers, including vein-graft and STEMI/NSTEMI patients and very small individuals.

"I think there might be some operators who are selective in who they will do, but when you're selective you're probably choosing the wrong patients, such as those who aren't going to benefit the most from the procedure," she said. "Also, you're never going to know how good you can get. I've just been surprised. I can do anybody."

Not just a bailout technique

Speaking with heart wire , Dr Sunil Rao (Duke University Medical Center, Durham, NC), who led the study examining the prevalence of trends and outcomes in radial-access PCI, said that US thinking must first change, particularly thoughts on using the approach only when the femoral route fails.

Dr Sunil Rao

"I think what we need to do is get away from the attitude that I grew up with, which is that you need to do the radial approach as a bailout technique," said Rao. "If you approach it from that angle, you're never going to get good at it. I think the data are very compelling, and there are multiple randomized trials, meta-analyses, and observational studies showing that there really is no downside. My take on it is that the radial approach should be the first approach, the default, and then femoral should be used as a bailout."

 
The radial approach should be the first approach, the default, and then femoral should be used as a bailout.
 

Like Tremmel, Rao said he did not learn the radial approach as part of his formal training. During his rotation, he performed just three radial diagnostic catheterizations, primarily because there weren't many being performed at Duke University when he underwent his training. However, he was forced to learn quickly in his first night as an attending physician when he was unable to gain access via the femoral artery because of an occluded aorta in an acute-MI case. At that moment, Rao decided to learn the technique because he didn't want to be placed in a nerve-wracking position again.

"I just had this sinking feeling because you suddenly realize you have to do something you're not very good at," he told heart wire .

Dr Mauricio Cohen

Another physician who performs transradial PCI is Dr Mauricio Cohen (University of Miami Miller School of Medicine, FL), a foreign medical graduate who trained in Argentina. While at the Hospital Italiano Buenos Aires, the leadership of the cath lab began looking at the benefits of transradial PCI, having already performed brachial-access PCI in certain patients to improve ambulation postprocedure and to quicken hospital discharge.

"I was exposed to radial, but I did not embrace it because the equipment was not entirely optimal," Cohen told heart wire . "There was spasm. There was radial-artery occlusion. There was an increased need to convert cases to femoral-artery access. Basically, I was suffering some of the inertia that a lot of physicians have about learning new techniques and new tricks, but it was not the ideal setting. I knew it was there, I knew it was doable, but it was still [not perfect]."

In 2003, after coming to the US and while working in a mobile catheterization lab outside Chapel Hill, NC, where they used femoral-closure devices in approximately 90% of patients, Cohen said one patient developed an infected aneurysm, and that procedure "left such a sour taste" in his mouth that he attended a course taught by expert Dr Tift Mann (Wake Heart and Vascular Associates, Raleigh, NC) in order to get up to speed on the radial approach.

In addition, Cohen was an investigator in a study examining the pharmacokinetics of eptifibatide in obese patients. Because these patients were very big, this required numerous maneuvers to find the groin, and because they were young with large radial arteries and unlikely to have severe vessel tortuosity, Cohen figured this was as good a place as any to start his career as a radial-PCI interventionalist. In 2008, his last year at the University of North Carolina before leaving for Miami, Cohen performed approximately 60% of his cases via the radial artery, and the entire group performed roughly 20% of cases radially, both well above national averages.

He said that most physicians can initially use standard diagnostic and interventional guide catheters, typically because these are the ones they know how to manipulate. After they become more familiar with the technique, they can transfer over to dedicated shapes of catheters that allow for cannulation of the left and right coronary artery, which eliminates the need for catheter exchanges, he said. Others noted that these dedicated radial catheters aren't 100% necessary and that all procedures can be performed with the same equipment used for the femoral approach.

In terms of setup, Rao told heart wire that he has patients place their arms at their sides, which is at the same level as the groin. The groin is prepped to avoid delays in case there is a need to switch to femoral access, which can occur in about 2% of cases, he said.

Technicians and nurses also need training in radial access, particularly since they look at the lab differently from physicians. However, as Cohen noted, once they see the advantages of transradial PCI, they often jump on board.

"The staff realized quickly that they didn't have to hold the groin of these large patients, and so they started to understand the benefits," he said. "They don't need urinals or bedpans because the patient can get up and go to the bathroom right away."

Getting started

To start a transradial program, there is very little that is needed, according to Cohen. Physicians can use a standard transradial kit, which includes a dedicated radial sheath, catheter, and puncture needle, and these are typically no more expensive than a transfemoral kit.

Dr Cohen performing a radial-access intervention

Patient on angiographic table with arm arranged on sideboards

Taking on nearly everybody

Most clinicians who perform radial PCI say the approach is one that is easily picked up by well-seasoned interventional cardiologists and usually requires just a few cases to become proficient and approximately 50 to 100 cases to introduce them to most variations in anatomy. Moreover, the technology has improved in the past few years, particularly with the development of hydrophilic sheaths and catheters that allow for smoother delivery through the radial artery.

Dr Mehrdad Saririan

"Honestly, it's not that different from a brachial approach," Dr Mehrdad Saririan (Maricopa Medical Center, Phoenix, AZ) told heart wire . "Most physicians know how to do the brachial approach, and this is really just an extension of that. People make it seem incredibly difficult to do, but it's not. So, I don't support the notion that you need 35 or 50 proctored cases to learn this. I think you can pick this up after one or two cases just by reading or observing someone else doing it."

Saririan, an interventional cardiologist, was trained in radial-access PCI at McGill University, where he did his cardiology fellowship. From there, he moved onto the Montreal Heart Institute, where transradial procedures were pioneered under D r Lucien Campeau, a physician who first used the right radial artery as an entry point for diagnostic catheterizations.

In addition to the advantages of reduced bleeding, increased ambulation, and reduced hospital length of stay, among others, Saririan said there is some measure of gratification knowing how to do the procedure as easily as the transfemoral approach and that he looks for reasons not to go the radial route. Some contraindications include an abnormal, or negative, Allen test, which suggests that dual blood supply to the hand is lacking. Some patients with renal insufficiencies might require later dialysis, so he uses the femoral route so as to not traumatize the radial artery. Also, he tends to exclude smaller patients, particularly women.

Radial artery punctured at the site of maximal impulse and at least 1 cm above the styloid process

 

 

Speaking with heart wire , Bertrand, who travels to give talks about the advantages of transradial PCI, said there are a number of myths surrounding the procedure, including misconceptions that the puncture of the radial artery is more difficult than a transfemoral puncture, or that the procedure is difficult to master. In addition, some still believe that radial PCI is only for selected patients or selected procedures, when in fact nearly all technologies can be employed with the radial approach. He added, however, that the miniaturization of existing technologies is a constant challenge.

"There are a few tricks to learn, but it doesn't take ages, and you don't need to be a rocket scientist," said Bertrand. "You can use exactly the same catheter, exactly the same technique. You can use exactly the same routine you have been using with the femoral approach. That's the message we're trying to get out."

Cohen said he thinks approximately 95% to 97% of patients are eligible for PCI via the radial artery. Very large catheters can't be inserted into the radial artery, nor can intra-aortic balloon pumps, he noted. Similarly, complex interventions requiring multiple catheters might be best left for femoral-access PCI.

He added that there is a learning curve and that clinicians should become proficient in simpler interventions before embarking on patients undergoing complex procedures or unstable patients. However, he now considers all acute patients from the emergency department for transradial PCI. "It doesn't take longer to get access, although it might take a bit of manipulation to go up though the brachial artery into the axillary artery and then into the ascending aorta, but that doesn't pose a problem in the majority of cases," he told heart wire .

Changing hearts, changing minds, and changing practice

While the technology is improving and the data are starting to accumulate, many proponents of the transradial approach say that changing the mind-set of practicing physicians, where "things are a done a certain way," remains a challenge. Bertrand told heart wire that part of the problem in the US is ingrained within the system and includes the greater use of closure devices, which add a cost to the procedure, and the use of physician assistants who compress the access site and manage the patient in case a hematoma develops.

"There hasn't been too much concern in the US about ambulation because the patient is going to stay in the hospital at least overnight," said Bertrand. "The reason the radial approach has started so fast in Canada, Europe, and Asia is because we don't have physician assistants. The doctor in charge of the patient is the same guy who has to push on the artery for half an hour at the end of the procedure. When you're treating six to eight patients and have to push on the artery for half an hour, it's a significant amount of time."

Rao pointed out, however, that there are also a number of low-volume operators in the US, those doing 30 to 50 cases per year, and these are likely highly selected cases that won't compel a clinician to do things differently. Older interventional cardiologists, said Saririan, those who developed the field, might not want to start learning new techniques at the end of their career.

Still, even for those that want to learn, it is not easy to find courses, say experts. Most physicians learning the radial approach do so through industry-funded courses.

"My first expectation is that people think of radial evangelists as a little bit kooky or a little strange, but what I've discovered is that people are extremely receptive to learning about it," said Rao. "They just don't know where to go or how they need to learn it. There is some frustration on the part of practicing interventional cardiologists that there isn't a professional society pushing the radial approach."

President of the Society of Cardiovascular Angiography and Interventions (SCAI), Dr Steven Bailey (University of Texas Health Sciences Center, San Antonio), said there has been a steady increase in the level of interest in transradial PCI in the past four or five years and in the number of cases being done.

"In terms of the society and members of the society, we certainly agree that radial access has many advantages over routine femoral access, and it is likely being underutilized," Bailey told heart wire . "One reason is that it is relatively new, so a lot of individuals have not been trained in it. Second is equipment. Radial access has its own unique set of challenges, so the equipment that a lot of folks train with, the femoral-access equipment, doesn't work nearly as well from a radial-access site. You can make it work, but you have to know what you're doing, and you have to know how to change your approach."

Dr Paul Teirstein (Scripps Clinic, La Jolla, CA), a high-volume interventionalist, said he performs just 5% of his cases radially, primarily because he believes the available tools are not yet good enough to handle some of the more complex cases, including bifurcation lesions, atheroectomy procedures, or highly tortuous vessels. For those procedures, which can require large or multiple catheters, the best approach remains the femoral artery, he said. However, Teirstein said he is gaining experience with the approach and imagines himself doing more cases in the future, if the technology improves.

Teirstein also mentioned that patients obviously prefer the radial approach, but some have complained of arm pain. In addition, he finds that radial procedures just take longer, although this is possibly because he is not as experienced with the radial approach as he is with femoral access.

Bailey said that SCAI plans to develop a training pathway for individuals who don't currently use radial access and create a set of guidelines for what the training courses should look like and what the process would be, to allow individuals to have more access to radial PCI. At the moment, there is no outline for what those courses will look like or what processes will be put in place.

"It will depend on when you were trained and how you were trained and what you're lab is like," said Bailey. "Not every lab is configured readily. It's more than just the physician-training issue, but how you facilitate this in a cath-lab environment. Although we have some ideas, it would be premature to say what it would look like."

Saririan said he thinks transradial PCI should be included in the guidelines as a class I recommendation and urged the professional societies to champion it as the preferred access route over the femoral approach. Another alternative would be for the radial approach, or at least an attempt at going the radial route, to be reimbursed at a higher rate than the femoral approach. "Either go to the guidelines or hit the pocketbook, and physicians will respond pretty quickly," said Saririan.

Cohen reports being on the speaker's bureau for Terumo Medical Corp, a manufacturer of equipment used for transradial interventions, and Tremmel also reports consulting for Terumo. Bertrand holds the EASY research and education fund in transradial PCI, supported by Cordis, Bristol-Myers Squib - Sanofi-Aventis, GE Healthcare, and the Corporation de l' institut de Cardiologie de Qu é bec. Saririan, Rao, Bailey, and Teirstein report no conflicts of interest related to transradial PCI.

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