Clinical Editor's Corner: Kern

A Light Bulb Goes On – My First Use of the Distal Radial Artery for the Left Arm Approach

Morton J. Kern, MD

Morton J. Kern, MD

My back ached at the end of the case. Several weeks ago, I performed left radial catheterization and angiography in an elderly man who had coronary artery bypass grafting 8 years earlier. We accessed the left radial in standard fashion, moved the arm to the abdomen with the radial sheath facing upward (an uphill battle in more ways than one), and placed folded towels under the drapes to prop the left elbow up and keep the arm centered. It was a struggle for me to reach over the large abdomen to get to the radial sheath and it was a struggle for our sleepy patient to keep his arm turned upward, and a struggle for everyone to keep the left arm centered even when the patient was cooperative. I was thinking how hard we worked to do left-sided arm procedures.

Last week, after returning from the Scottsdale Interventional Forum and hearing about distal transradial (dTRA) access, particularly for left arm cath, I decided to give it a try. I spoke to several operators with experience, viewed Dr. Ferdinand Kiemeneij’s YouTube video on how to do distal radial artery access, and reviewed his and several other excellent articles published over the last year describing the technical details.1-5 While in no way unique or a first of its kind, this initial experience was instructive to us. I thought it might be worthwhile to others as well. Here’s what we did.

Step by Step for dTRA Access

The left arm was prepped and draped as normal, using the Armen glove method.6 We palpated the artery over the anatomic snuffbox on the back of the hand and marked it, mostly for teaching purposes, but also to help focus our ultrasound imaging on the entrance site. Dr. Kiemeneij noted that we could bring the artery to the surface of the fossa by asking the patient to grasp his thumb under the other four fingers with the hand slightly abducted. All we did was put a towel under the wrist to flex the hand downward. It seemed to work just fine.

As recommended by others, we generously injected lidocaine, giving 10 cc slowly to limit discomfort in case we went too deeply with our needle. We visualized the lidocaine over the artery with ultrasound.  We then visualized the artery again with ultrasound imaging and used our micropuncture kit with a metal needle and an .018-inch wire (Figure 1), watching the needle enter the artery at an angle of 30-45 degrees and from lateral to medial to make only a front wall stick. The wire passed smoothly and following a small skin nick, the 5 French (Fr) sheath insertion went forward without a problem (Figure 2).

We continued the case in a routine fashion with heparin 5000U IV and diluted 250 mcg intraarterial verapamil to limit artery spasm. We secured the sheath with a Tegaderm clear plastic dressing, then moved the arm with the palm of the hand facing downward (in the normal ergometric position) (Figure 3) over the abdomen. Buttressed with several rolled towels, the left arm was relaxed and easily reached from the right side of the table. Angiography proceeded easily using Judkins left (JL) 4, Judkins right (JR) 4, Amplatzer left (AL) 1, left internal mammary artery (LIMA), and a pigtail. Catheter exchanges were easily controlled, holding the sheath during multiple exchanges. We also had good control of the catheters during manipulation to access the coronary ostia.

Hemostasis for dTRA Access

At the end of the procedure, we planned to use a TR Band (Terumo), since it was our only band at the time. After moving the left arm back to the arm board and preparing to apply the band, we realized that the TR Band has a stiff plastic rib that helps maintain pressure over the radial (or ulnar) artery at the level of the wrist, but does not permit the band to conform to the hand at the level of the snuffbox. We removed the plastic rib (Figure 4) from the TR Band, placed the band over a StatSeal patch (Biolife), and inflated the band with 10 cc of air. Hemostasis was achieved with good flow to the hand. The band was removed 1 hour later (we probably could have removed it after 30 minutes, but as this was our first case, we erred on the side of caution). The patient went home 4 hours later with just the StatSeal patch, to be taken off after his next shower (Figure 5).

Common Indications for Left Radial and dTRA Access

The most common reasons to use the left radial artery include need for LIMA angiography, known complex aortic arch anatomy (bovine truncus or arteria lusoria), known problems with the right radial artery (occlusion, small size, radial loop, significant arterial sclerosis or calcifications), presence of an arteriovenous shunt in the right arm, and patient preference. Of somewhat lesser concern, dTRA advocates cite that for the right-handed patient, the left radial access is more convenient because of the free use of the right hand after the procedure. In addition, this technique reduces the chance of radial artery occlusion at the site of the distal forearm. Interestingly, there is less radiation from the left than right arm approach.7

Unusual Use of a Right dTRA – Dr. Arnold Seto’s Case

A most unusual circumstance required a unique solution. We had a patient who absolutely refused to lie on his back because of back pain and anxiety. However, for some reason, he was perfectly willing to lie on his left side. Given this problem and need for coronary angiography, he was positioned on his left side with the right arm up (Figures 6-8). In this case, access to his radial artery posed a significant ergonomic challenge, so distal right radial access was performed as described above without incident. We were able to perform coronary angiography with extreme modified angulations of the C-arm to achieve the normal left and right anterior oblique (LAO and RAO) views as we would if the patient were lying flat. Hemostasis was also well managed as described above, but without the StatSeal. Overall, the right dTRA saved the day for this patient.

Cautionary Notes

While our first case was a great experience in that the artery puncture was easy and the sheath slid into the artery easily as well, we recognize that there may be difficulties ahead.8-12 We will be cautious about using an artery <2.5 mm in diameter and feeling resistance to wire or sheath movement, as well as catheter-induced spasm. The distal radial artery is smaller, making puncture more challenging. Double wall puncture is discouraged as the periosteum of the bony structures can be very sensitive to needle contact. Care for good hemostasis is always important. A learning curve has to be overcome. In a small series of patients, the distal radial artery was too weak to attempt a puncture at the radial fossa in 23% of cases.1 However, this also reflects caution on the part of the operator when starting a new technique, for which only the most suitable patients are selected. Dr. Avtandil M. Babunashvili, at the Center of Endosurgery in Moscow, Russia, who pioneered distal radial artery access, reminds us that in a substantial number of patients, no clear pulse is palpable in the anatomical snuffbox. The left distal radial approach will not replace standard transradial access as the default strategy, but it can be considered in patients who prefer or require a procedure via the left arm in the presence of a palpable artery in the anatomical snuffbox.

The Bottom Line

A series of excellent reviews of the history, anatomy, and techniques of distal radial artery access (dTRA) can be found in CLD and elsewhere. In our lab, we had a positive experience all around. After the procedure, we reviewed what we did and how to make it part of our routine left arm access (at least for me at this time). The patient was comfortable throughout the procedure and importantly, the operator [M.K.] was also comfortable in accessing and exchanging catheters without back strain. It is likely this technique will be even more appreciated by the vertically challenged operators among us as well, as reaching across the patient can be very difficult. We hope this anecdote on dTRA is another helpful word on improving arm access for our patients needing a left-sided approach. 

  1. Kiemeneij F. Left distal transradial access in the anatomical snuffbox for coronary angiography (ldTRA) and interventions (ldTRI). EuroIntervention. 2017; 13: 851-858.
  2. Kiemeneij F. Video of distal transradial artery access. Oct 4, 2017. Available online at Accessed May 9, 2019.
  3. Flores EA. Making the right move: use of the distal radial artery access in the hand for coronary angiography and percutaneous coronary interventions. Cath Lab Digest. 2018; 26(12). Available online at Accessed May 10, 2019.
  4. Kiemeneij F, Klass D, Nathan S. Keep an open mind about distal radial access. Cath Lab Digest. 2019 Mar; 27(3). Available online at Accessed May 10, 2019.
  5. Lardizabal J, Cohen MG. Right versus left radial artery access. Cardiac Interventions Today. 2012 May/June. Available online at Accessed May 10, 2019.
  6. Kern MJ. The Armen glove for radial access prep – a better way. 2010 May; 18(5). Available online at Accessed May 10, 2019.
  7. Sciahbasi A, Romagnoli E, Burzotta F, et al. Transradial approach (left vs right) and procedural times during percutaneous coronary procedures: TALENT study. Am Heart J. 2011; 161: 172-179.
  8. Fernandez-Portales J, Valdesuso R, Carreras R, et al. [Right versus left radial artery approach for coronary angiography. Differences observed and the learning curve]. Rev Esp Cardiol. 2006; 59(10): 1071-1074.
  9. Guo X, Ding J, Qi Y, et al. Left radial access is preferable to right radial access for the diagnostic or interventional coronary procedures: A meta-analysis involving 22 randomized clinical trials and 10287 patients. PLOS ONE. 2013 Nov; 8(1): 1-9. Available online at Accessed May 10, 2019.
  10. Cerda A, del Sol M. Anatomical snuffbox and its clinical significance: a literature review. Int J Morphol. 2015; 33: 1355-1360. doi: 10.4067/S0717-95022015000400027
  11. Babunashvili A, Dundua D. Recanalization and re-use of early occluded radial artery within 6 days after previous transradial diagnostic procedure. Catheter Cardiovasc Interv. 2011; 77: 530-536.
  12. Koutouzis M, Kontopodis E, Tassopoulos A, et al. Hand hematoma after cardiac catheterization via distal radial artery. J Invasive Cardiol. 2018; 30(11): 428.