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Page 2 of 7 D’Abramo et al. Vessel Plus 2019;3:4 I http://dx.doi.org/10.20517/2574-1209.2018.41

the main features of these different options and explore what kind of open questions these newer-generation prosthetic
valves and delivery devices carry.

Keywords: Aortic valve surgery, aortic valve stenosis, cardiac surgery, sutureless, transcatheter aortic valve implantation, new-
generation devices, minimally invasive technologies

INTRODUCTION
Aortic valve stenosis is the most clinically relevant valvular heart disease in the elderly people with a
prevalence of 21%-26% in the elderly above 65 years of age and it increases with age, determining prognosis
[1]
worsening after symptoms occurrence . Surgical aortic valve replacement (SAVR) has represented, for
decades, the standard treatment for patients with symptomatic and severe aortic stenosis, resulting in relief
of symptoms, in a significant improvement of clinical outcome and in an improved survival. Although SAVR
still represents a valid option in the setting of aortic valve stenosis, transcatheter aortic valve implantation
(TAVI) proved to be superior to medical therapy and comparable-non inferior to SAVR in several
[2-4]
randomized trials as well as in registries . Following its introduction in 2002, with the first case performed
[2]
in Rouen by Cribier et al. , TAVI has become an established treatment for patients with severe symptomatic
aortic stenosis deemed inoperable or at high risk for conventional surgery. About 300,000 procedures have
been performed worldwide with the first and second-generation CE-marked devices: Medtronic CoreValve®
TM
TM
(Medtronic, Minneapolis, MN, USA) and Edwards SAPIEN /SAPIEN XT (Edwards Lifesciences, Irvine,
[5]
CA, USA) with an annual compound growth rate of 40% . Due to an overall increased experience and
[6]
the progressing technology in transcatheter valve systems , TAVI has been proposed and used in patients
who are at intermediate and even low risk. The analysis of the Cohort A of the randomized trial PARTNER
2 showed that TAVR was non-inferior to surgical aortic-valve replacement in terms of primary end-point
[8]
[7]
of death or disabling stroke . Therefore, recently published European guidelines has reinforced TAVI
recommendation in intermediate risk patients (class Ib, level of evidence B). Moreover the growing aging
population, characterized by greater co-morbidities and risk profiles has led to the development of minimally
[9]
invasive technologies to reduce surgical impact on patients. An increasing number of surgeons are now
endorsing minimally invasive aortic valve replacement through the sutureless valve technology (or rapid
deployment valve). With this new emerging technology, TAVI, reasonable issues arise in comparison with
surgical techniques and need to be answered: (1) which has the longest durability; (2) which encompasses the
lower complication rate; and (3) the lower overall mortality.

SURGICAL AND INTERVENTIONAL APPROACHES
Patients usually can be scheduled to undergo a SAVR through conventional full midline sternotomy or mini-
access according to the surgeon’s discretion and/or patients characteristics. In these two settings, patients
can receive either a conventional stented or sutureless prosthesis. Compared with conventional surgery,
minimally invasive access can provide shorter hospital stay, improve postoperative respiratory function and
reduces postoperative pain, blood loss and blood transfusions thanks to the lower invasiveness. Commons
minimally invasive approaches are: the partial upper ministernotomy, the right anterior minithoracotomy,
the right parasternal approach from the second to the fourth costal space and the transverse sternotomy.
Surgical approach, minimally invasive or not, still represents the standard of care for several reasons: it
has the longest follow up, it can be performed in younger patients, in patients with intermediate-low risk
profile, in patients requiring combined cardiac procedures or a redo operation. Open-heart surgery allows
controlled and accurate decalcification of aortic annulus and consequently a safe valve positioning under a
direct visualization and with a major leaks control. In specific condition, also an aortic root enlargement can
be performed with this approach. On the other hand, standard surgical intervention is a time-consuming
procedure in term of cardio-pulmonary bypass (CPB), cross-clamp and myocardial ischemia times. Patients