Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_3609_Библиотеки_им_академика_М_И_Перельмана

This is a description of how the standard technique of trans­femoral CAS with lter-type distal embolic protection is

performed at the authors’ institution. Undoubtedly, there will be many other ways of executing the procedure, but this reects only the authors’ personal preference and experi­ence. Patients are started on dual antiplatelet therapy that includes aspirin 100mg once a day and clopidogrel 75mg once a day, preferably for a minimum of 1week prior to the procedure. The intervention is performed while the patient is awake without sedation. Consequently, the patient’s neu­rologic status can be monitored during each step of the pro­cedure. Under local anesthetic inltration with xylocaine 2%, a common femoral artery (CFA) puncture is performed. If a diagnostic carotid digital subtraction angiogram (DSA) is needed prior to the CAS procedure, a 5F-11 cm groin sheath is introduced. Otherwise, if both the aortic arch and the carotid anatomy have been adequately documented at previous imaging (CTA, MRA, DSA) and the intention is to proceed directly to transfemoral CAS, a 7F-11 cm groin sheath is introduced. Once femoral access is secured, the patient is anticoagulated with intravenous heparin, usually 5000units or a dose needed to achieve an activated clotting time of >250s. A 5F diagnostic catheter (often a Headhunter or Simmons 2) is advanced into the aortic arch with the aid of a 260cm-long, J-shaped, 0.035-inch hydrophilic coated guidewire (Terumo Glidewire, Terumo Europe NV). If an aortic arch DSA is needed, for instance, when severe ostial stenosis of an arch vessel is suspected or when difculty accessing the carotid arteries is encountered, this is usually performed in the left anterior oblique (LAO) projection (30– 50°). Roadmapping can be useful in guiding the cannula­tion. Depending on the target carotid side, the catheter is then advanced either through the innominate or through the left common carotid artery (CCA) into the mid-CCA, and a diagnostic selective carotid angiogram, including baseline intracranial runs, is obtained. Normally, we advance a stiff guidewire into the distal external carotid artery (ECA) and exchange the diagnostic catheter (and the 5F groin sheath) for a 7F-11 cm sheath and a 7F, 100-cm long, JR4-type guiding catheter. Our preferred guiding catheters are the Launcher (Medtronic) and the MACH1 (Boston Scientic). In cases of tortuous anatomy, when extra support is needed for exchanging the diagnostic catheter with the guiding catheter, a stiffer guidewire may be necessary, such as the 260cm-long, J-tip, Amplatz Superstiff Guidewire (Boston Scientic). From this point on, all subsequent procedural steps are executed through this guiding catheter, a technical approach known as the direct approach to CAS. Other endo- vascular specialists prefer the telescopic approach, i.e., exchanging the diagnostic catheter and groin sheath for a long introducer sheath (often a 6F, 90-cm-long Super Arrow-Flex® Sheath, Teleex, Teleex Medical Europe Ltd.; or 6F, 90-cm-long Destination Guiding sheath, Terumo Interventional Systems, Terumo Europe NV), which serves as the working channel.