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Page 4 of 10 Sticchi et al. Vessel Plus 2018;2:23 I http://dx.doi.org/10.20517/2574-1209.2018.47

TRANSAPICAL ACCESS
The transapical access must be performed under general anaesthesia and preferably in a hybrid operating
room in order to have the surgical and transcatheter equipment ready for use and to the best of the possi-
[21]
bilities . Briefly, a small left anterior mini-thoracotomy is performed in the fifth-sixth intercostal space to
expose the apex of the left ventricle after opening the pericardium. In order to visualize and fix the operating
window, the pericardium is anchored with several points to the skin. Polypropylene sutures forming a purse
concentrically, usually in the number of two, are positioned catching wide portions of cardiac apex tissue.
[22]
So, via the above-mentioned threads, the operator introduces the sheath into the left ventricle . After trans-
catheter placement of the valve, the sheath is retracted and the sutures are tightened during rapid ventricular
pacing to maintain low pressure in the final repair time. Transapical access approach is a “surgical” proce-
dure without impairing of the thoracic cage and has the theoretical advantages of stroke prevention avoid-
ing to cross the aortic arch with the device during the delivery [21,22] . Contrary to the direct aortic approach,
[23]
transapical approach can be used only with the SAPIEN valve that can be assembled backwards . This ac-
cess is advantageous especially in patients in whom the pre-procedure evaluation shows characteristics that
determine a high risk of stroke and embolism as in the case of extensive calcifications, porcelain aorta and
[22]
thrombus finding in the aortic arch .

DIRECT AORTIC ACCESS
Direct transaortic access is one of the possibilities of a transcatheter implantation using a surgical access and
it is either performed by a J-shaped mini-sternotomy or a right thoracotomy. The purpose of the operating
window is to visualize an initial portion of the ascending aorta for the introduction of the valve delivery
device. Depending on the anatomical position of the aorta, one of the two windows is suggested. The right
thoracotomy is recommended in cases where the aorta runs in the right hemithorax and superficially near
the rib cage, while the mini-sternotomy is chosen in those cases in which the vessel is in a central and deep
[24]
position . Once the window is realized, a suture bag is obtained on the designated aorta section for the
final closure and, in the center of the managed area, the access to the vessel is first performed with a needle
puncture and then with the device. The insertion of the device into the aorta must take into account the type
of valve that is implanted, for example for Medtronic CoreValve a distance of at least 6-7 cm from the valve
plane is necessary in order to ensure the complete deployment of the skeleton from the sheath. Using this
wire as a rail, the device slides up to the aortic valve. In this approach, the position of the valve prosthesis is
promoted by the shortness of the path between the access and the valve and by the absence of stress on the
device as it happens in the femoral access for the passage in the aortic arch. Favourably, these conditions al-
low a short learning curve by the operator [25,26] .

After the valve implantation, the device is withdrawn while the previously prepared suture threads are tight-
ened to close the vessel wall, the technique is comparable to decannulation after cardiopulmonary bypass.
Finally, the chest wall is restored as usually occurs in cardio-thoracic surgery. The hemisternotomy allows
to protect the pleura and to visualize and handle a large portion of aorta in which to select the access point.
In case of patients with coronary bypass graft, it is advisable to use the thoracotomy to avoid its course [25,26] .
Finally, the direct aortic approach is suitable if the patient has a horizontal valvular plane or a particularly
straight ascending aorta [25,26] .

TRANSUBCLAVIAN
The approach through the subclavian artery takes advantage of a light sedation and local anaesthetic. In or-
der to adequately display the artery, an incision is made between the deltopectoral groove and the pectoralis
major. This technique is less invasive than a real surgical support and, at the same time, it overcomes a pos-
[27]
sible impairment of the peripheral accesses . The brachial plexus, one of the most important nerve bundles
of our body, is located above the subclavian artery and for this reason it is fundamental to protect it from