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Sticchi et al. Vessel Plus 2018;2:23 I http://dx.doi.org/10.20517/2574-1209.2018.47 Page 5 of 10
[28]
complications such as artery dissection or pseudoaneurysm . The artery can be highlighted by a band if it
is accomplished through a surgical isolation and, as seen in other accesses, a suture purse is created with a
5-0 polypropylene thread on the front side of the vessel, both for safety and for the final closure. Consider-
ing a vessel without calcific disease, a minimum of 6 mm is required for the introduction of a 18Fr sheath
while in the case of the presence of a patent’s left internal mammary artery graft, the diameter must be at
least 7.5 mm to maintain a sustainable downstream flow [27,28] . The artery is pierced with a standard needle
which is inserted in the center of the prepared sutured area, on that insertion point a soft 0.035 wire with a
J-tip is introduced and a 6 Fr sheath is inserted on it. A catheter slides over the wire in the ascending aorta,
then the soft wire is replaced with a super-stiff Amplatz wire. So, in order to get the 18 Fr sheath through the
subclavian artery in the proximal ascending aorta, a series of increasing size of dilators, from 10 Fr, 12 Fr,
14 Fr up to 18 Fr, follow each other at the insertion point [27,28] . The succeeding steps for the valve deployment
adhere to the standard protocol of the procedure. After the sheath is removed, the purse-string suture is tied
under direct visualization that would determine if additional sutures are needed. Continuous advances of
this technique have recently leaded to publications of fully percutaneous procedures without surgical cut-
down [27,28] . However, these improvements are not yet able to displace surgical exposure as the routine prac-
[29]
tice . Performing a transubclavian approach may be particularly challenging if the aortic plane forms an
angle greater than 30 degrees with the horizontal plane. This complexity derives from the curving that the
device must perform and from the consequent tension on it, increasing the difficulty in the proper deploy-
ment of the prosthesis [28,29] .

Furthermore, the occlusion of the vessel by the sheath or any damage to neighbouring vascular structures
may result in dangerous ischemia, especially when it involves the flow of an internal mammary artery graft
with possible myocardial infarction in the most severe conditions [28,29] .

TRANSCAROTID
Among the possible strategies, an approach with a direct and short road to reach the planned position at the
aortic valve plane is always recommended. This can also be achieved with the carotid access as well as with
[30]
the transaortic and transapical approach . A short path also allows a better support and greater precision in
[30]
valve distribution than the femoral approach . The patient is evaluated preliminarily to define the possibil-
ity of performing the procedure with the necessary occlusion of one carotid and therefore the maintenance
[31]
of an adequate cerebral flow through the Willis circle from the contralateral carotid . This is assessed by
placing a shunt in the vessel to measure passive anterograde pressure in the common carotid artery, then
[31]
the procedure is performed using a small cut as access under local anaesthesia . The first series with this
[32]
approach, through the proximal left common carotid artery, is reported by Modine et al. and it counts 12
consecutive cases performed under general anaesthesia. The study does not report peri-procedural events,
vascular complications or bleedings, the only adverse event recorded is an embolic transient ischemic attack
[32]
starting from the contralateral carotid access . Later, a study publishes a series of cases under local anaes-
thesia using both balloon expandable and self-expandable valve. Even if the study does not report access site
complications, major adverse cardiac event or stroke, two patients died, one during valvuloplasty and one for
multiple organ failure. Finally, three patients developed a third-degree atrioventricular block resulting in a
[30]
definitive pacemaker implantation . Therefore, we can conclude that this type of approach requires further
studies and technical evolutions in order to be able to enter currently as an access option, considering also
the possible aesthetic issue that could derive from it.

TRANSCAVAL
Another recently developed approach is the transcaval-aortic access which can be a useful alternative in
cases of severe peripheral artery disease. The access puncture is performed at the femoral vein site, reaching
the abdominal aorta and creating an artificial cava-aorta fistula. The characteristics of the venous wall allow