Despite a growing evidence that the radial approach – as compared with the trans-femoral approach – is associated with reduced bleeding and mortality in patients undergoing coronary diagnostic and interventional procedures , the worldwide adoption of such technique has been heterogeneous, as reflected by the discrepant recommendations available in major current guidelines. Indeed, the ESC guidelines strongly recommend the radial approach as the preferred vascular access, with a class of recommendation I and level of evidence A, whereas the AHA/ACC guidelines do not provide any specific recommendations on the vascular approach .

A default radial access is routinely feasible after appropriate training, better results being expected with increasing procedural volume of operators. Radial artery occlusion is the major complication, variously reported with a wide range of variability (1–33%) and frequently underestimated because asymptomatic; non-occlusive radial compression, adequate heparinization and careful nurse monitoring are major determinants of radial patency . Apart from patients with the Raynaud’s phenomenon and lymphedema – usual contraindications to radial access – all subjects with palpable radial arteries are suitable for trans-radial approach and the routine assessment of the dual palmar arch circulation – although still recommended – has been almost abandoned in routine clinical practice.

The indications for trans-radial access are expanding due to miniaturization of the devices used, improvements in techniques and increasing experience. There are several reports highlighting the feasibility of radial approach in challenging procedures, but the largest survival benefit over femoral access seems evident among subjects with higher bleeding risk, namely elderly and STEMI patients.

Randomized controlled trials have until now mostly been designed on the comparison between radial and femoral access, leaving several issues not yet specifically addressed in the optimal management of patients undergoing coronary procedures with radial approach.

The Italian Society Interventional Cardiology (SICI-GISE) therefore endorsed a survey, querying the practice patterns of interventional cardiologists on the radial approach. In the current issue of the Cardiovascular Revascularization Medicine journal, Rigattieri et al. provide an intriguing snapshot of the implementation of radial approach in Italian practice. In Italy, the use of radial access has steadily increased, almost doubling in the last 5 years. Noteworthy the methodology of survey, other than providing an interesting mean of information acquisition, raises some potential concerns as the system lends itself to potential gaming of polls. Obviously, one of the challenges of an internet survey is how representative and valid are the responses. “Radialists” were probably more encouraged in participating than “traditional” femoral operators did, and this would be difficult to control or adjust for.

The most relevant finding of the present survey resides in the absolute confidence that the majority of responders have in the radial access. Such confidence becomes rather dogmatic in some clinical settings. Only a minority of physicians (20.6%) consider end-stage renal disease or hemodialysis as a limitation to the utilization of the radial approach. We share the same concern of the authors on this issue and warn interventional cardiologists to refrain from the use the trans-radial access in hemodialysis patients, whose outcome is strictly dependent on the patency of the arteriovenous fistula, as also reported in the consensus document on the radial approach .

Similarly, we believe that the femoral approach should be preferred in patients with previous surgical revascularization, when a double in-situ mammary artery conduit has to be cannulated; although the majority of responders agree with the use of a femoral approach, there is still a relevant amount (24%) of interventional cardiologists who would perform the double mammary artery cannulation starting from the radial approach, and this implies either a tortuous navigation through two subclavian systems or a bilateral radial access. However, we must acknowledge that in some cases proximal subclavian kinking prevents proper manipulation of the catheter from the aortic arch and trans-radial access is mandatory to obtain a selective cannulation of the mammary artery ostium.

As for side preference, most operators (88.6%) use right access for comfort reasons, although left radial access ensures easier catheter maneuvers, more similar to the femoral approach. This survey clearly documents a low level of awareness among responders in terms of radiation exposure. Operators’ perception is absolutely wrong, as left radial is considered by far the worst approach in terms of operator’s radiation exposure among left, right radial and trans-femoral approaches. A robust meta-analysis documented that trans-radial access is associated with a small but significant increase in radiation exposure in both diagnostic and interventional procedures compared with trans-femoral access . As for radial site preference, a more recent meta-analysis documented a small but statistically lower contrast use and fluoroscopy time in favor of coronary procedures performed via left radial as compared with right radial approach, without any significant difference in access site or other procedural complications . As for operator radiation exposure, Sciahbasi et al. confirmed in a phantom study that the use of left as compared with right radial access was associated with a significant lower radiation dose at wrist and thorax but with an increased dose at hip level. Worryingly, Rigattieri’s survey responders overlook pelvic lead shield, never used by 66% of physicians, in spite of a documented reduction of the radiation dose of the operator at several sites (under lead apron, on thyroid collar and left side of head) .

Heparinization is of paramount importance to prevent radial artery thrombosis, and the consensus document suggests 50 IU/kg or 5000 IU bolus of unfractioned heparin, although available data on the issue of optimal dosing are sparse. Righteously, most of the responders administer periprocedural heparin, although large incertitude between 2500 and 5000 UI doses persists.

Although it is not yet time for femoral access to pass into history for good, trans-radial should be the preferred approach for coronary diagnostic and interventional procedures, and – due to the overwhelming scientific evidence – current guidelines should uniform their recommendations. After the conclusive findings of the Minimizing Adverse Haemorrhagic Events by Trans-radial Access Site and Systemic Implementation of Angiox (MATRIX) study , future trials should step further and explore beyond the crude comparison with femoral approach, aiming to identify the “optimal” management of patients with radial approach. On their side, interventional cardiologists should increase their awareness on patient’s and operator’s safety, and restrain from being “blind supporters” of a strategy over the other. A selective approach, according to patients’ clinical presentation, comorbidities and anatomical complexity should always be advocated.