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A good understanding of some key features of the local anatomy is essential for both optimal access and ideal management of the puncture site. Careful attention to access and careful evaluation of the access site are fundamental to reduce sheath insertion trauma and lead to uncomplicated sheath removal and the safe use of vascular closure devices.

It is important to puncture at the level of the common femoral artery. This allows compression of the vessel against the femoral head at the time of sheath removal. Punctures below the common femoral arterial bifurcation (hence in the profunda femoris or the superficial femoral artery) are over soft tissue and are difficult to compress (Figures 2.1 and 2.2). Such punctures have been shown to be associated with increased risk of pseudoaneurysms and arteriovenous fistula formation [5,6]. Punctures above the inguinal ligament (hence in the external iliac artery) are in the retroperitoneal space which also represents an incompressible space. Such high punctures are associated with increased risk of retroperitoneal bleeding [6–8].

Figure 2.1 Femoral artery angiogram taken after sheath insertion. The sheath has been inserted into the superficial femoral artery (SFA). The profunda femoris or deep femoral artery is labeled PF. The sheath terminates in the common femoral artery (CFA). The arrow denotes the lower margin of the curve of the deep circumflex iliac artery. This lower border of the curve courses along the inguinal ligament. Punctures above this landmark are usually adjacent to the retroperitoneal space and poses a high risk for bleeding complications.

Figure 2.2 Bilateral femoral artery angiograms. On the left panel, a line is drawn through the level of the mid femoral head. This is normally an ideal location for puncture. In this case, however, the femoral artery bifurcation is above the mid femoral head and the sheath can be seen entering the deep femoral artery. The right panel shows the left femoral angiogram. A line is drawn at the level of the top of the femoral head, showing a remarkably high bifurcation in this patient. Even though the sheath insertion on this side is just below the top of the femoral head, it is also in the deep femoral artery. Although this puncture is compressible over the femoral head, the branch is relatively smaller than the common femoral artery and less well suited for use of closure devices.

Landmarks on fluoroscopy are useful for identifying the position of the common femoral artery. About 75–80% of the common femoral bifurcation is at or below the inferior border of the femoral head and 95% is at or below the mid femoral head [5,9]. While the inguinal ligament is not visualized under fluoroscopy, the deep circumflex iliac artery is commonly used as a surrogate marker of the upper border of the common femoral artery because it is the last arterial branch of the external iliac artery before the external iliac courses under the inguinal ligament and becomes the common femoral artery (Figure 2.1). The deep circumflex iliac artery arises from the lateral aspect of the external iliac artery nearly opposite the origin of the inferior epigastric artery. It ascends obliquely laterally behind the inguinal ligament, contained in a fibrous sheath formed by the junction of the transversalis fascia and iliac fascia, to the anterior superior iliac spine. Puncture above the most inferior border of the course of the deep circumflex iliac artery has been associated with increased risk of retroperitoneal hemorrhage. This landmark is above the most superior border of the acetabulum in most patients [6].