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Page 2 of 9 Candela et al. Vessel Plus 2018;2:28 I http://dx.doi.org/10.20517/2574-1209.2018.31

INTRODUCTION
Aortic stenosis is the most common and dangerous cardiac valvular disease, which a reported incidence of
[1,2]
2%-4% of patients over 65 years . Aortic valve replacement (AVR) is the current standard treatment for
[3]
severe aortic stenosis , nonetheless, many patients are not suitable to AVR because of high risk related to
advanced age, impaired cardiac function, relevant comorbidities such as chronic kidney disease or chronic
obstructive pulmonary disease. In addition, heavily calcified aortas, previous mediastinal radiation, and
redo valvular surgery expose patients to a prohibitive risk for standard AVR. Given these considerations,
transcatheter aortic valve replacement or implantation (TAVR or TAVI) has emerged in the last decade
as an alternative to surgery and has become the treatment of choice for severe aortic stenosis in patients
[4-6]
with prohibitive surgical risk . The goal of this procedure is minimizing surgical trauma by avoiding
sternotomy, aortotomy, cardiopulmonary bypass (CPB) and by implanting the prosthetic valve on beating
heart, thereby avoiding cardiac arrest, in order to decrease perioperative risks and improve patient
[7]
outcomes . Depending on patient characteristics, TAVR can be performed using different access sites
including transfemoral (TF), trans-subclavian/trans-axillary, transaortic, or transapical approaches [8-10] .
The most commonly used approach to performing TAVR is the TF approach by retrograde deployment
of the valve passing through the ascending aorta. Most of the centers prefer TF approach because it is less
invasive and is associated to a reduced percentage of cardiac related complications, therefore it continues to
[11]
be the main approach used on patients without severe vascular disease . Alternative access sites are used
on patients with severe peripheral vascular disease and short vessel segments with iliac-femoral arteries
diameters < 7 mm [12,13] .

In the context of this kind of hybrid procedure, the anesthesiologist plays a central role because the choice
of anesthetic technique is strongly related to clinical features of the patients and technical considerations,
which must be discussed collegially with the operators. The most important consideration for the
anesthesiologist member of the care team is the type of anesthesia most suited for the patient. The choice
of anesthesiologic management is different among hospitals, but it is generally based on preoperative
comorbidities, procedural approach used for TAVR and even hospital logistics [14-18] . Some centers used
to perform TAVR under general anesthesia (GA), some else under local anesthesia with a mild sedation
(LAS), some of them start their TAVR program under GA, but convert in LAS when the team get enough
experience. The aim of the anesthesiologist should be to provide less-invasive anesthesia/analgesia without
compromising the safety or comfort of the patient. The aim of this article is to provide a general overview
about anesthetic techniques in TAVR and to evaluate pathways for future researches.

FROM AVR TO TAVR… AND FROM GA TO LAS
Although GA is considered mandatory in case of transapical or transaortic approach, there has recently
been a significant increase in literature showing the safety and efficacy of local anesthesia with LAS com-
pared with GA when TF approach is performed [19,20] . At the beginning of a TAVR program, most centers
initially chose to provide GA for this procedure, but as the team developed with enough experience and
confidence with the procedure, many hospitals started to convert GA in LAS. Actually, the preferred anes-
[21]
thetic management is equally split among centers providing GA vs. sedation for TAVR .

The induction of GA can be performed with a variety of agents, often with a reduced dosage and a very
slow administration because of advanced age and decreased cardiac function. Surgical stimulation is
not much painful, so the procedure does not need elevated dosage of opioids. Inhalational agents may
have some advantages on myocardial protection [22-26] thanks to a pharmacological preconditioning and
postconditioning action. Studies performed on patients undergoing coronary artery bypass graft (CABG)
surgery, showed lower postoperative values of cardiac troponin because of the cardioprotective effect of
inhalational agents. Short-acting drugs, such as Remifentanil, that are rapidly cleared are preferred to