Gentleman, Rebel and Believer: the Radial Way
Vincent Dangoisse,
Département cardiovasculaireCliniques Universitaires U.C.L. de Mont-Godinne Yvoir, BELGIUM

The first time I had the chance to meet Dr Lucien Campeau (picture 1), a long time ago, longer than I care to remember, I was a fellow of the Montreal Heart Institute, Canada. Dr Campeau, former head of medicine, was known to be a “solo” clinical researcher and at this time he was completing his long-term study addressing the late patency of the saphenous vein and mammary artery grafts: he is credited by his US colleagues as the scientist who proposed the mammary artery as the graft of choice for coronary artery bypass graft surgery (CABG) surgery. This contribution is already considerable. But Dr Campeau has to be credited with a second and equally tremendous contribution: a few years after the graft story, he was the first to study scientifically the vascular access for coronary catheterization. In 1989, he published his landmark study of the first 100 consecutive coronary angiograms through a radial artery canulation performed by himself, of course and, like the brilliant clinical researcher he is, he immediately understood the major benefit of the Trans-radial Approach (TRA): an access to the arterial bed worry-free of vascular and bleeding problems1. His report draws the starting line for the Transradial Approach. From my first meeting to the last time I saw him in summer 2008, at the annual Montreal Interventional Cardiology Symposium, he has represented for me the perfect illustration of a true “gentleman” evolving in the medical field.

although this was in reference to the computer he used for his presentation (his computer was not running the dominating operating system), I recognize the same attitude in his way of pushing the TRA. He is to be lauded for turning a complete catheterization laboratory staff into a full and almost exclusive TRA for coronary angiogram and angioplasty laboratory. He is to be credited also with the “modified Allen test” using the plethysmo/saturometer to assess more objectively the patency of the ulnar and of the radial arteries 2, with definition of four different types of response during compression of the radial artery. Indeed, he was a “rebel” in the face of the long list of doubts still prevalent and he worked hard to prove the feasibility of PCI through the TRA. The TRA’s story is fortunately strewn with other “believers”, such as Dr Kiemeney, who initiated percutaneous coronary intervention (PCI) through the TRA 3 and who organized in his country a lot of conferences on the subject of TRA (I participated in one of the last Amsterdam meetings).
I also had the opportunity to meet Dr Martial Hamon, now at the University Hospital of Caen, France, when he was a fellow in my first teaching hospital (the CHUS, Sherbrooke, Canada) at a time when I practiced through the trans-femoral approach (TFA): I never imagined that a few years later, he would be one of the well-known defenders of the TRA in his country. He has to be credited with an excellent textbook 4, (I offer his book and the marvelous Patel’s Atlas of Transradial Intervention 5 to every participant in my TRA seminars). He has done a good job, since the rate of TRA use is said to be around 50% in France.

Correspondence:Dr, VINCENT DANGOISSE,Professor, Chef deCardiovascularise Cliniques Universitaires U C L de Mont-Godinne Av Thérasse, 1, B-5530 YVOIR,BELGIUM

E-mail: vincent.dangoisse@uclouvain.bevdangoisse@mac.com

occlusion”, “TRA requires a higher volume of contrast and results in a higher X-ray exposure”, “TRA is associated with a long learning curve”...
Indeed, application of TRA is the preserve of the “rebel” and “devotee” if such a list of assertions is true!
Becoming a believer effectively requires a “conversion” and a conversion usually requires good motivation. My own motivation to switch from TFA to TRA was strong, although not the best one: it was based on economic grounds. If I wanted to continue to do angioplasty, I had to find a way to reduce the hospitalized time after catheterization because the university hospital where I was working in Montreal was cutting the number of beds as a cost reduction exercise. The TRA was my response and it worked so well that I became ... a believer.
Nevertheless, the only reason for adopting TRA must be the safety feature associated with it, and this is best illustrated by picture 2: this photo shows the skin at the wrist level the day after a TRA catheterization and illustrates the discovery of Lucien Campeau: an access to the arterial bed worry-free of bleeding and of vascular problems. I usually regard this a-traumatic entry site as the only trace left by our “minimally invasive cardiology”.
Very soon after my personal switch, I began to look at my own practice and I was more and more convinced of the untruths surrounding the TRA. Figures 1 provide the mean X-ray time and the mean volume of iodine contrast I used during my transition period (from January 2000 to June 2002): after a steep learning curve, I finally worked more efficiently when using the TRA. I did the same observation for the time the patient had to stay in the catheterization room (ten minutes fewer) and it was particularly true for some kinds of populations (namely senior and elderly women).
Thereafter, in 2004, I had the opportunity to spread the “TRA Word” in my homeland, starting a nationwide TRA teaching program, and I credit myself with the complete conversion of at least two catheterization laboratories, not counting the other new believers disseminated in other hospitals across my country. Figure 2 depicts how quickly the switch occurred for the laboratory in which I still work.Having the chance to start a TRA program in a “TRA naïve” hospital, I set up with my colleague and friend Antoine Guédès, a dedicated database tracking the problems related to the different steps linked with successful catheterization when TRA is offered for every left heart catheterization. By protocol, TRA

Figure 1Personal learning curve illustrated by the evolution of mean iodine contrast volume (ml) and mean fluoroscopy time (minute) for both diagnostic and interventional procedures during years 2000 to 2002.

Figure 2

Illustration of the conversion from TFA to TRA for our catheterization laboratory:  number of PCI through TFA versus TRA during the period of transition (2004-2005).

was offered to everybody, as soon as at least one radial artery was palpable and the protocol mandated that both radial arteries be attempted first before converting to a TFA. After nearly two thousand consecutive procedures (under review manuscript), we concluded that
1/ TRA succeeds in about 98-99% of all cases no matter the type of procedure (diagnostic or interventional) and no matter of the type of patient (female or male, old or young, post CABG surgery or not, etc.). In other words, we need a femoral artery canulation for only 1-2% of our cases.
2/ When we fail to canulate one radial artery, we have at least an 80% chance to proceed successfully through the contra-lateral radial artery (a good motivation for considering the second radial artery).
3/ More than 50% of problems or failures arise at the puncture or sheath insertion steps, where the clinical consequences are indeed very limited.

Vincent Dangoisse,

4/ Best predictors of failed radial canulation are available at the bedside: these factors are the operator experience, the presence of a history of peripheral artery disease, a weak pulse or a small artery as assessed by the physical examination: thus, there is no need for sophisticated devices.
5/ Radial arteries of seniors and women are easier to damage locally (be more gentle...man).
The conversion of our catheterization laboratory to a complete TRA laboratory allows us to perform another analysis, breaking down another misconception: the success rate of angioplasty 6.
Excluding the one-day PCI patients (patients going back to their referring hospital), we performed 554 PCI in 2003, 544 through trans-femoral access (TFA) and ten through TRA, and in 2007, numbers were going in the opposite direction: 560 PCI, nine through TFA and 551 through TRA. Figure 3 depicts the PCI success rate during 2004 and 2005, when most of the shift occurred in our laboratory: even during this transition period, success rates stayed much the same. Furthermore, when we analyzed 3600 PCI patients from 2002 to 2007, the 1672 TRA-PCI success rate was 96.1% versus 95.3% for the 1928 TFA-PCI (of course, p=ns).
More importantly, as soon as TRA was introduced, transfusion of blood products declined with the need for vascular surgery. Adding such unhappy events to the well-known major events (death, M.I., stroke and urgent CABG surgery), we noted significant reduction in an in-hospital “global index”: 51 (7.5%) of such events occurred in the TFA group during 2004 and 2005 versus 23 (3.9%) for the TRA group (p= 0.006, Figure 4).
Figure 5 depicts the evolution of this global index for all the PCI population until 2006, the reduction being statistically significant (p= 0.048). Interestingly, we also observed a reduction in the rate of NSTEMI but because of the non-randomized nature of our analysis, we can only speculate about the probable role of the TRA: its use allowed us to prescribe three times as many upstream GP IIb/IIIa inhibitors ( 23.7% use for TRA PCI versus 7.4% for TFA PCI). Our observation is in accordance with recently published reports showing the global clinical benefit of TRA 7, 8.
This observation could be the starting-point for future research on TRA: we have to construct projects showing the global superiority of TRA in terms of both vascular events and of ischemic protection which may safely be optimized with TRA.
The reported occlusion rate of radial artery post-catheterization is one of the problems a “club of believers” should address collectively: what is the true incidence at one and 30 days post-catheterization, what are the most important predictive factors and, more importantly, what could be done to reduce this occlusion rate to the minimum? Can we think about re-canalizing the artery? Chances are that occlusion happens when the local trauma is too intense: bad ratio catheter size/ artery diameter, over-thrombotic material, over-forceful manipulation, too intense and/or too prolonged compression, etc. A few months ago we started a prospective study to confirm the PROPHET study 9, looking if reducing compression intensity as far as possible can be translated into more frequent patent radial artery, and we invite believers to join our “CRASOC” (Compression of the Radial artery Sans [without] OCclusion”) protocol. 
In the list of “untruths”, the only one with which I agree somewhat is the assertion regarding the existence of a learning curve. After our analysis of 2000 TRA, we know that the problem arises predominantly at the level of puncturing/wiring the artery itself, the other problems being quite easily recognized, and working solutions for such problems are easy to teach. Beginners have to invest in their skill of puncturing and wiring the artery: this fact has to be addressed by future research looking at better material and our teaching has to focus on it. Speaking about the learning curve, we can reassure future believers: even for beginners, TRA succeeds for at least 90% of the time: look at the performance of the first “radialist”, Dr Campeau himself.

Figure 3PCI Success Rate (%), TFA versus TRA, during the period of transition (2004-2005). “Partial success” refers to failure for at least one of the attempted lesions.



Figure 4 PCI during 2004 + 2005, TRA versus TFA, and the Global Index (%), a composite index of adverse in-hospital events post angioplasty (death, MI, urgent CABG surgery, stroke, blood transfusion or vascular surgery)



Figure 5 Global index: yearly evolution from 2003 (98% TFA) to 2006 (92% TRA) of the composite index of adverse in-hospital events post PCI, regrouping death, MI, urgent CABG surgery, stroke, blood transfusion or vascular surgery. The decline of this global index coincides with the 2004-2005 period of transition and is statistically significant (p= 0.048).