The Transradial Approach

Does your fellowship training program teach it?

By Jennifer A. Tremmel, MD, MS

For more than 40 years, the femoral approach has been the dominant method of vascular access for diagnostic and interventional procedures in the United States.1 Brachial artery cannulation, the original access point for coronary procedures, was quickly relegated to a backup strategy, and the transradial approach has been slow to catch on, despite being introduced more than 20 years ago.2 However, a change of tide across the United States can be felt as interest in the transradial approach swells. This change is occurring as several factors converge to create a tipping point, including an increased concern regarding vascular access and bleeding complications, a growing interest in improving patient satisfaction, greater governmental and administrative pressures to reduce costs and length of hospital stay, and an improvement in transradial equipment and availability of training.

Despite the recognized benefits of the transradial approach compared with the femoral, or even brachial approach,3-12 there are several reasons for the longevity of femoral access as the default strategy. Femoral access is effective, easy to learn, and relatively safe. It also allows for the use of large-bore catheters, and most sheaths, catheters, and guidewires are designed with the femoral approach in mind. Perhaps even more powerful is tradition. Invasive and interventional cardiology training is an apprenticeship, and most teachers in the United States are femoral operators. Students, in turn, eventually teach what they have learned to someone else, and so the tradition continues.

Training program guidelines in the United States mirror our current system of teaching the femoral approach as the default strategy and make no specific stipulation for transradial training (Table 1). The third edition of Task Force 3 of the American College of Cardiology (ACC) Core Cardiology Training Symposium (COCATS) guidelines state that a level 3 trainee (interventional cardiology fellow) should possess the cognitive knowledge and technical skills outlined in the ACC training statement that was published in 1999.13 This never-updated ACC training statement says, “Trainees should be experienced in the full range of arterial vascular access techniques. These should include both transfemoral approaches and approaches from the arm.”14 Likewise, the current Accreditation Council for Graduate Medical Education (ACGME) Program Requirements for Graduate Medical Education in Interventional Cardiology makes the statement that “fellows must have formal instruction, clinical experience, and must demonstrate competence in the performance of…coronary interventions [via] femoral and brachial/radial cannulation of normal and abnormally located coronary ostia.” Although this document is undergoing modification, with the updated version expected July 1, 2011, there is currently no apparent editing to this particular statement.

To be a level 2 trainee (one who will practice diagnostic but not interventional cardiac catheterization), the COCATS guidelines state that one needs the ability to “perform vascular access from the femoral, radial, or brachial route.” Arguably, being able to perform catheterization from only one of these access points without being able to perform an alternative method, if needed, is not adequate. Ideally, a graduating fellow would be able to perform vascular access from the femoral, radial, and brachial route. Although transfemoral training is necessary, and proficiency in the brachial approach is desirable, neither adequately prepares an operator to perform a transradial procedure. If it did, there wouldn’t be the growing demand for transradial training that we are currently seeing among practicing invasive and interventional cardiologists in the United States. To perform radial procedures, extra training is needed, even if it is a small amount, and there is no better time to do that than during fellowship.

Diagnostic and interventional cardiology training is an influential period when fellows acquire a fundamental framework of cognitive and technical skills. After fellowship, operators may trial and adopt new devices and techniques, but their ease in doing so varies depending on the breadth of the fundamental framework they developed during training. In addition, finding the time and patience to learn new skills and techniques after fellowship is a challenge. Therefore, fellows want to (and should) enter programs in which they can gain the broadest exposure possible to optimize their repertoire of abilities prior to entering practice. As the field continuously evolves, we too must continuously reflect upon how we are doing at preparing the next generation of invasive and interventional cardiologists. If we want our trainees to graduate with a fundamental framework of cognitive and technical skills that allow them to adapt with the times and provide the safest and most comfortable care to patients, we need to consider transradial training to be as important as femoral training. It is time to update the training guidelines to clearly reflect this evolution in our tradition.

Training fellows is a challenging but rewarding process. Anyone in academic medicine knows the cycle of watching their fellows turn into independent operators as the academic year rolls on, and then suddenly in July having “production” come to a screeching halt. You stand there for minutes watching a needle go in and out of a groin, mysteriously unable to puncture a large, pulsating femoral artery. Teaching the wrist is similar, although the radial artery is even less forgiving, with spasm sometimes making multiple attempts at cannulation nearly impossible. Because of this, when to train fellows in the transradial technique and which fellows to train remain open questions. Our current practice is to have the first-year general fellows focus on mastering femoral access and its complications. Our interventional fellows get to do all available radial sticks during the first half of the year, and during the second half, senior (second-year) general fellows who are planning on doing an interventional fellowship or going into invasive cardiology can start to learn the technique. While there are no current competency guidelines, it is suggested that a well-trained graduating fellow will have done at least 50 transradial cases.

When last investigated, < 2% of all percutaneous coronary interventions (PCIs) in the United States were performed transradially.9 However, many would argue that this number is quickly on the rise, with a growing number of interventionists obtaining training in transradial procedures. As more attending physicians learn and practice this technique, more interventional fellows are completing their training having truly mastered “the full range of arterial vascular access techniques.”

Although data regarding this new generation of radially trained fellows and recent graduates are lacking, one senses they may soon be changing the landscape of interventional cardiology in the United States. To get an idea of this, I asked several current fellows and recent graduates from across the country to give their perspective on the transradial approach.

While the excitement of learning something novel is apparent in their use of words like “fantastic” and “sweet” to describe transradial intervention (TRI), certain other themes also emerge. Whether or not they know the data, they know firsthand that bleeding and vascular complications are less frequent and that their patients are more comfortable. They also report having a skill that makes them a more attractive candidate when looking for a job. They acknowledge the learning curve, but also know that, as with everything else they have done, they get better with practice. Some fellows who have been equally exposed to the wrist and groin do not seem to distinguish between the two in terms of effectiveness or ease. I suspect that if we all had a similar early exposure to the transradial approach, we would all feel the same way.

Jennifer A. Tremmel, MD, MS, is an interventional cardiologist at Stanford University Medical Center in Stanford, California. She has disclosed that she is a paid consultant to Terumo, Medtronic, and Abbott Vascular. Dr. Tremmel may be reached at


Fellow, Interventional Cardiology
Geisinger Medical Center
Danville, PA

I was exposed to radial access right from my generalcardiology fellowship. It started with one interventionistwho was interested in using it as the preferred accesssite, with others using it in cases in which the femoralapproach was not possible or not appealing. An initialperiod of increase in procedural time and learning curveon behalf of the fellows and catheterization laboratorystaff has given way to a time in which a majority of thecatheterization laboratory attendings now use the radialapproach preferentially, and most senior fellows are justas comfortable with the radial approach as the femoralapproach.

For me, the first challenge was being successful ataccess. It would always surprise me how easy it was forme to get an arterial blood gas via radial access, yet howdifficult it initially was to achieve access for radial arterycatheterization. Some of the learning points for me werecareful planning of access, minimizing lidocaine injection,adequate pain control and sedation, paying closeattention to the course while advancing the initial wire,using respiratory maneuvers to negotiate tortuosity,making very small movements with the catheters, andalso being vigilant of hand perfusion after the procedurevia pulse oximetry. I think it is important to make theradial approach the primary approach for most patientsto acquire some degree of comfort with the procedure.We now even perform complex PCI procedures, includingrotational atherectomy via the radial approach, feelingjust as comfortable with it as the femoral approach.

The advantages to learning the radial approach for ageneral cardiology and interventional cardiology felloware tremendous. My first reason for using the radialapproach preferentially when I go into practice is that itmakes cardiac catheterization a much better experiencefor my patients and eliminates the feared groin complications,particularly severe hemorrhage. It is also preparesme well for the patient in whom a femoralapproach is not possible, especially in the ST-elevationcohort, in which time to revascularization is important.All cardiology practices that I have interacted with havebeen very eager to have a radial interventionist onboard. Also, because radial access has been a fairlyrecent adaptation in the United States, it gives me theopportunity to teach and take leadership in the adaptationof this approach in whichever institution or practiceI join.

Fellow, Interventional Cardiology
Penn State M.S. Hershey Medical Center
Hershey, PA

As a cardiology fellow, and now as an interventional fellow,I have had the opportunity to participate in hundredsof cardiac catheterization procedures, with approximatelyhalf being done via the femoral approach and half by theradial approach. Radial artery access is infrequently used inthe United States, which has been attributed to a steeplearning curve for performing cardiac catheterizationthrough the wrist. However, because my training hasincluded both radial and femoral access, I have not foundone method to be easier or more difficult than the other.Certainly, there are patients for whom catheterizationusing the radial artery for access is significantly easier thanthe femoral artery and vice versa. However, for mostpatients, either radial or femoral artery access could beused with equal effectiveness and ease. I have observedthat patients who have had both forms of access preferradial access, and many patients have requested to havetheir procedure performed through the wrist. I have alsoobserved that the nursing staff in our institution prefertaking care of patients who have had the radial artery usedbecause access site and patient care is simpler. Radialartery access complications are rare and typically notsevere, whereas I have seen a few patients with severefemoral artery access complications. Arterial access hasbeen of particular importance in many acute cases in criticallyill patients, and the ability to quickly and safely useeither the femoral or radial artery for access has been avaluable skill. Many fellows in the United States receive littleor no exposure to radial artery access, and this may bea disservice to them and their patients. As a fellow, I haveappreciated the training I have received because I feel itallows me to be more flexible with the method of arterialaccess used and thus provide patients with the safest andmost appropriate access. Because radial artery access issafer and preferred by patients and is as easily utilized as femoral access, I certainly intend to use radial artery accessin most of my patients in my future practice.

First year in practice, Interventional Cardiology
Sir Charles Gairdner Hospital
Perth, Western Australia

One of the most rewarding parts of Australian cardiologytraining is the encouragement we get to train overseas.It offers an often once-in-a-lifetime opportunity to pick upa new set of procedural skills. TRI has been one of themost useful skills I obtained in fellowship. Australia has traditionallynot had a strong TRI focus, and I had little exposureto it prior to my American training. My initial reactionwas quite negative. TRI requires a different skill set thantransfemoral, and I was frustrated by the difficulties I hadinitially with access, spasm, and engagement of the coronaryostia—I felt like a first-year fellow again! The learningcurve was quite steep, but there was a noticeable improvementafter about 25 cases, with my success rates increasingfrom around 60% to 90%. I quickly realized that guide supportwas often superior from a transradial approach comparedwith transfemoral, and I enjoyed the assurance that Iwas unlikely to be called back for access-site bleeding afterleaving for the day. I also learned that almost all cases canbe performed transradially, including grafts, infarct PCI,rotational atherectomy, and chronic occlusions.

I have since returned to Australia. My current practiceis to perform approximately 75% of cases by a transradialapproach. I now train my own fellows in TRI, and as muchas possible, I allow them to struggle through the initiallearning curve and am proud when they become confidentand “converted” to TRI as I have been.

Fellow, Cardiovascular Disease
University of California, Irvine Medical Center
Orange, CA

I have always felt that the number of procedures andthe speed with which they are performed are importantbut only secondary to the quality of care provided tothe patient. At UCI Medical Center, I have been lucky tohave great mentors who continue to emphasize thisideal. In this regard, we started training using a transradialapproach to perform cardiac catheterization.Although the transradial approach has been technicallychallenging, access and overall procedure time hasdecreased with continued practice. Having experiencewith both the femoral and transradial approach isinvaluable. I believe that being able to provide patientswith an option that is associated with a marked reductionin the risk of both minor and life-threatening vascularsite complications will only help me provide thebest care possible in my future practice. Removing outcomesfrom the equation, I cannot emphasize moreclearly how much our patients have appreciated thetransradial approach in terms of sheer comfort andconvenience. As cardiac catheterization techniques andintravascular stent technology advance, we are providedwith tools that facilitate better outcomes for ourpatients. For example, when confronted with borderlinecoronary artery stenosis or indeterminate stent apposition,the use of fractional flow reserve or intravascularultrasound helps us do the right thing. In an analogousfashion, knowing how to use and convert to a transradialapproach in a patient with difficult femoral accesswill ultimately improve the care we provide. And that iswhat it’s all about: doing the right thing for ourpatients. I have to admit that the transradial approachdoes take time to learn, and this is mainly due to learningwhich catheters to use and how to manipulate thembecause initial radial access is relatively easy; however,the end result is worth the steep learning curve.

Fellow, Interventional Cardiology
Stanford University Medical Center
Stanford, CA

I am a big fan of the transradial approach. Virtually allof my patients who have had femoral and radial proceduresprefer the latter. From my standpoint, with the radialapproach, I sleep better at night—I don’t worry about alate night phone call regarding bleeding, and I don’t worryabout the patient sitting up or lifting their leg. From thepatient’s standpoint, they love the fact that they can situp right away, and that they are not immobilized forhours. I find the radial approach particularly favorable inthe overweight patient—I find the wrist more accessiblethan the groin, and any bleeding is more readily apparentwith the transradial approach. I find the radial approachfavorable in patients with back pain who have difficultylaying flat for several hours. Achieving hemostasis is easierusing TRI, and any rare rebleeding from the access site iseasily managed. We’ve done ST-elevation myocardialinfarctions (STEMIs) with excellent door-to-balloon times,left main stenting, graft cases, bifurcation lesions, andchronic total occlusions. In the overwhelming majority ofcases, I have not felt at all limited by the radial approach.The access in the majority of cases has been very straightforward,with only a handful of cases having challengingtortuosity. There are a small proportion of patients whoneed to be converted to a femoral approach. By the sametoken, there are patients with poor femoral access whobenefit from conversion to a radial approach. Transradial training going forward will be an increasingly importantpart of an interventionist’s toolset. I believe that it isimportant to learn both radial and femoral approaches.When you really look at what is best for the patient, Ithink transradial cases provide a higher level of patientsafety without compromising interventional options.There is a learning curve—acquisition of a new skillrequires practice. Having said that, within 3 months ofearnest radial training, I am as fast or faster with angiographyfrom the radial approach versus the femoralapproach. When coupled with right heart catheterizationfrom the antecubital veins, there is no question that thisis a more efficient procedure, with decreased risk to thepatient and shorter recovery times. When given thechoice, most patients choose a transradial approach. Thedemand exists, and I think training in the transradialapproach will help fulfill that demand.

Chief Fellow, Interventional Cardiovascular Medicine
Lahey Clinic Medical Center
Burlington, MA

am very grateful for having the opportunity to betrained in transradial PCI. We are the only catheterizationlaboratory in the greater Boston area doing a significantnumber (> 50%) of our cases via the radial approach.Having the opportunity to have appropriate, high-volumetraining in transradial PCI is fantastic. It has allowed me toconsolidate a skill that is immensely useful and has directbenefits to all subsets of patients undergoing PCI.

The transradial program at Lahey Clinic has severalstrengths. It is led by a knowledgeable and skilled practitionerin transradial PCI, Dr. Chris Pyne, and we perform alarge number of cases annually. This is important becausethere is a steep learning curve, and persistence and encouragementare needed to become comfortable and proficientwith this skill. Completing a fellowship that offers suchgreat training in transradial PCI means that I will be confidentto offer and use the transradial approach in patientsneeding diagnostic angiography or PCI. Increasingly, there isstrong demand for radial interventionists. Having this skillwill provide more opportunities for employment, particularlyin the United States where training in and the uptakeof this approach, has been slower than in other parts of theworld.

First year in practice, Interventional Cardiology
Orange County, CA

As a fellow, learning the transradial technique is bothfrustrating and rewarding. After refining my skills performingcardiac catheterization primarily from the femoral approach, I was initially skeptical of the practical utility ofthe transradial approach. Most interventional fellows aremore excited about guidewires, angioplasty, and stentsthan performing basic diagnostic studies. The learningcurve is steep because you must retrain your hands to dothings differently during the entire case, from obtainingvascular access to catheter manipulations. With patience,persistence, and confidence, eventually enthusiasm for thetechnique makes you wish all cases were performed radially.

The ability to perform transradial procedures is aninvaluable asset when interviewing for positions. Practicegroups are excited about adding associates who can offerpatients alternative procedures that improve patient satisfactionand reduce complications, especially in the subsetof patients that are at high risk for bleeding. There may bepotential barriers in starting radial procedures. I cannotoveremphasize the importance of support from the hospitaladministrators and the catheterization laboratory staffin order to become a successful radialist. Most communityhospitals do not have the specialized equipment, or thecurrent equipment in supply is outdated. Unfortunately,transradial cardiac catheterization has been stigmatizedfrom earlier experiences that it is too time consuming ordifficult. It can be a challenge to convince catheterizationlaboratories to invest money and time to support thismodality. In addition, patient education needs to bestressed. Some patients in nonteaching hospitals may behesitant to consent to procedures that are outside of whatmost cardiologists in the community are performing. In theend, if the procedure has a proven benefit to the patientand has demonstrated cost-effectiveness, the hospital willsupport the physician’s needs.

Fellow, General Cardiology
University of California, Irvine Medical Center
Orange, CA

Our program began the transition to a transradial lab atthe start of my catheterization laboratory rotation as a firstyearcardiology fellow. This proved to be especially challengingbecause I was still in the process of learning thestandard femoral approach. However, I initially noticed thatthere was less pressure involved with the transradialapproach because you could worry less about high or lowsticks, a major concern among first-year fellows. The learningcurve was in fact steep, and we tested numerous newtransradial catheters and hemostasis devices. Once we set aprotocol in place and had a dozen or so cases under ourbelts, the procedure became more efficient. In fact, we nowuse the transradial approach for select STEMI patients.

As a fellow interested in interventional cardiology, having this technique as part of your skill set is invaluable. It is anapproach seeing significant growth currently, and exposureto it early in training is important. Prior to our transition, wewould only attempt a transradial approach in a patient withsignificant peripheral vascular disease in whom femoralaccess may be limited. These are often not the ideal patientson which to learn. Now our approach of choice is radial, andwe only switch to femoral if unsuccessful, or with renalpatients. Patients are often surprised that we have the technologyto offer them this approach. After the case, I havenoticed that they are unanimously in favor of it, especiallythose that have had a transfemoral catheterization in thepast. And from the fellow perspective, managing the wrist ismuch easier and preferable to managing the groin.

First year in practice, Interventional Cardiology
Overton Brooks VA Medical Center
Louisiana State University Health Sciences Center
New Orleans, LA

I was first exposed to the transradial approach as anInterventional Cardiology Fellow at Geisinger while workingwith Dr. Kimberly Skelding. I felt lucky because most peoplewould have to travel elsewhere and pay fees to be trainedon transradials. It was sweet doing radial PCIs because Iknew I would not have to deal with groin complicationsand an unhappy patient later on. The learning curve isthere, but the compensation is well worth it.

Receiving transradial training as a fellow changes yourview of the interventional landscape forever. Understandingthat there is little you cannot accomplish via the wrist issomewhat radical. But the young mind of a fellow candigest this fact easier than someone already out in practice.It took me a while to digest it—until I saw Dr. JamesBlankenship do a rotational atherectomy case via the wristand a STEMI via the left wrist. That erased any doubts I hadthus far.

Receiving training on transradial has set me apart already.I have started a transradial program at my new job. Wehave been able to provide service (diagnostic and evencomplex interventional procedures) to morbidly obesepatients, patients with severe peripheral vascular disease ofthe lower extremities, and fully anticoagulated patients successfullyand without complications. We are using the transradialapproach routinely in many of our outpatients.Being able to do this makes me feel accomplished and tobe recognized this early in my career as the “transradial person”is fantastic.

It is time for general cardiology and interventional fellowsto have mandatory training in transradial access. Only thenwill there be a significant increase in the utilization of thetechnique and a substantial reduction in the incidence ofbleeding complications. Only then will routine outpatientradial PCIs be a reality.


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About Cardiac Interventions Today

Cardiac Interventions Today (ISSN 2572-5955 print and ISSN 2572-5963 online) is a publication dedicated to providing comprehensive coverage of the latest developments in technology, techniques, clinical studies, and regulatory and reimbursement issues in the field of coronary and cardiac interventions. Cardiac Interventions Today premiered in March 2007 and each edition contains a variety of topics in a flexible format, including articles covering various perspectives on current clinical topics, in-depth interviews with expert physicians, overviews of available technologies, industry news, and insights into the issues affecting today's interventional cardiology practices.