Samir B. Pancholy, MD, MSCAI; Hany Ragy, MD, FSCAI; Faisal Latif, MD, FSCAI

Introduction

Transfemoral access is frequently obtained exclusively by palpation¹ using superficial landmarks that have been shown not to correlate with the femoral artery anatomy.²

The common femoral artery has been shown to be the safest puncture site for transfemoral access.³ Puncture sites above the inguinal ligament and below the femoral bifurcation are associated with a significantly higher risk of access site complications with poor outcomes.³ Following best practices for transfemoral access may lower the burden of femoral access site complications.

Transfemoral access in the contemporary era is generally required while using large-bore catheters in patient substrates with high complexity, as well as sometimes in urgent or emergent situations, all at an outcome disadvantage – hence increasing the importance of the practice of safe femoral access.

In this Tip of the Month, we focus on strategies to obtain safe femoral access to lower the risk of access site complications.

Highlights

Ultrasound-Guided Access

Using ultrasound, the operator can ascertain the location of the bifurcation of the common femoral artery into superficial femoral and profunda femoris arteries. The ideal puncture site is in the segment of the common femoral artery immediately above the bifurcation, which can be precisely located by ultrasound. Ultrasound examination also allows for evaluation of the health of the arterial wall at the intended puncture site. Avoiding arterial puncture in calcified segments of the common femoral artery wall aids in obtaining proper hemostasis after catheter removal. This is especially important when using large-bore femoral access.

Limitations of Ultrasound Guidance

The most important limitation of ultrasound guidance is limited spatial resolution, with the inability to confidently define the proximal end of the “target zone,” as the target zone is marked by the inferior horn of the inferior epigastric artery, which can only be clearly visualized using angiography.⁴ Also, it is of practical value to aim for the location of the puncture site on a bony platform such as the femoral head or the pelvic brim, which would then allow for effective compression to obtain hemostasis. These bony landmarks are difficult to visualize by ultrasound. These variables are likely responsible for the higher incidence of “high” puncture in the ultrasound-guided arm of the FAUST trial.⁵

Micropuncture Access

Micropuncture access allows the operator to perform femoral angiography before inserting a larger caliber catheter, confirming the superior aspect of the safe zone of the puncture, which is marked by the inferior horn of the inferior epigastric artery. It also corroborates other anatomic details.⁶ Abandoning puncture sites with micropuncture access allows for much easier hemostasis afterward due to a smaller puncture.

Limitations of Micropuncture Access

Since the micropuncture catheter is of a much smaller caliber and the guidewire has a very flexible tip, the tactile feel associated with guidewire advancement such as the feeling of resistance, etc. is not as robust as it is with the traditional spring-tip guidewires. Also, the smaller caliber guidewires are capable of entering small branches, and this – in combination with a decreased tactile feel – may lead to inadvertent aggressive advancement into a small branch causing perforation, a large hematoma, and other access site complications. This can be mitigated by observing the advancement of the micropuncture guidewire under fluoroscopy to ascertain the placement of the guidewire in the central lumen of the femoral and external iliac arteries and further.

Practical Pointers

A combined strategy of fluoroscopic assessment of bony landmarks and an ultrasound-guided arterial puncture in a segment without significant atherosclerotic burden – and especially calcification with unequivocal ascertainment of femoral bifurcation – will allow the operator to target the ideal common femoral puncture site while using transfemoral access.

As ultrasound imaging has limited spatial resolution, using micropuncture access with subsequent hand injection femoral angiography will allow the operator to confirm the puncture site location in the ideal zone, as well as to get a better spatial orientation of the access site.

Conclusion

A strategy of using a combination of fluoroscopic guidance and ultrasound to precisely locate the common femoral artery and the use of micropuncture access to further confirm the proximal boundary of the “target zone” can allow the operator to perform safe femoral access.

References

1. Damluji AA, Nelson DW, Valgimigli M, et al. Transfemoral Approach for Coronary Angiography and Intervention: A Collaboration of International Cardiovascular Societies. JACC Cardiovasc Interv. 2017 Nov 27;10(22):2269-2279.
2. Grier D, Hartnell G. Percutaneous femoral artery puncture: practice and anatomy. Br J Radiol. 1990 Aug;63(752):602-04.
3. Sherev DA, Shaw RE, Brent BN. Angiographic predictors of femoral access site complications: implication for planned percutaneous coronary intervention. Catheter Cardiovasc Interv. 2005 Jun;65(2):196-202.
4. Holland BH, Applegate RJ. Femoral Vascular Access – Approaches and Available Devices. Interventional Cardiology. 2012 Jan;7(2):108–14.
5. Seto AH, Abu-Fadel MS, Sparling JM, et al. Real-time ultrasound guidance facilitates femoral arterial access and reduces vascular complications: FAUST (Femoral Arterial Access With Ultrasound Trial). JACC Cardiovasc Interv. 2010 Jul;3(7):751-8.
6. Turi, ZG. Optimal Femoral Access Prevents Complications. Cardiac Interv. Today. 2008 Jan/Feb:35-38.