Twenty years after it was first proposed as an alternative to the transfemoral approach, the transradial approach is now seen as the preferred approach for coronary interventions—indeed, considering the transradial approach is associated with a lower risk of bleeding and mortality, there seems little rationale in using the transfemoral approach whenever the transradial approach is feasible. However, before we abandon “the good old femoral route” completely, the advent of structural heart disease interventions means that we still have a use for the approach. I will explores the use of the transfemoral approach with these interventions.
Vascular access and its management are, respectively, the first and the last steps of any interventional procedure. Structural heart interventions are associated with a real potential for damage to the iliofemoral axe or the aorta itself because of the large dimensions of the current technology used in these interventions. As the approach to the femoral artery in this context differs from the conventional coronary 5Fr to 8Fr approaches in many aspects, the optimal transfemoral approach for structural heart interventions deserves cautious consideration.
Firstly, there is the site and modality of the puncture. This must be confined to a precise segment of the common femoral artery above its bifurcation and below the origin of the inferior epigastric artery. To identify the right spot, a diagnostic angiogram must be performed beforehand—either in a precedent angiographic procedure or during the same procedure but using a radial artery or the contralateral femoral. A computed tomography (CT) scan is also recommended to analyse the anatomy and diameters of the vessels and to detect the degree and distribution of calcium in the arteries.
The puncture should avoid calcified plaques located in the anterior wall of the common femoral artery and enter coaxially the artery with a 50–70 degree angulation from the skin. Externally, the puncture site will appear extremely high (closer to the navel than to the leg!) as compared with the conventional puncture site of a coronary procedure.
Before implanting the large femoral sheath, some important recommendations must be considered. One is the positioning of a “safety wire” along the common femoral artery-superficial femoral artery axe, normally a 0.018 inch supportive wire crossing anterograde from the contralateral femoral artery. An alternative may be a retrograde wire inserted from the homo-lateral superficial femoral artery and left into the thoracic aorta. This wire permits immediate access to the puncture site in case of artery rupture, bleeding or occlusion requiring treatment with balloons or stents.
The second consideration is the correct pre-implantation of a percutaneous closure device. The learning curve of these techniques is not obvious, and should not be added to the learning curve of the structural procedure itself, in particular transcatheter aortic valve implantation (TAVI). Therefore, a surgical femoral approach may be considered until the team is proficient in performing the structural procedure. In this case, the protection wire is not necessary.
Third, there is a trick that is worth sharing. While the new Edwards’ Sapien 3 valves can be implanted through 14Fr to 16Fr e-sheaths, operators still struggle to use an 18F sheath to implant a CoreValve (Medtronic). There is no reason to cause such unnecessary trauma to the artery wall to implant a CoreValve as all of them will easily go through the 14Fr Edwards’ e-sheath. Simply try!
Fourth, you should be familiar with the use of peripheral long sheaths, wires, balloons and stents. These are essential to solve complications (that are frequent in TAVI procedures), and do not even start a percutaneous femoral procedure without all the material on site.
Fifth and finally, avoid total anaesthesia. Patients who are awake can help you to understand immediately if something is going wrong.
In experienced hands, the femoral route is the safest to perform TAVI procedures given its minimal invasiveness compared with other surgical approaches such as transapical or transaortic, and the most difficult transfemoral will is still safer than the easiest surgical approach.
With currently available technology and accurate technique, more than 95% of TAVI can be performed via the femoral artery. Surgical approaches should be limited to impossible femoral cases. Other arterial access (subclavian or carotid) have not found indications in current practice and so far represent local experiences by dedicated teams that may not be replicable.
Flavio Ribichini, director Cardiovascular Interventional Unit, Division of Cardiology, Department of Medicine, University of Verona, Italy