Abstract
Introduction : Nowadays micro-invasive procedures (off-pump,
beating heart) for mitral valve repair (MVRe) are abruptly expanding
with the potential to be adopted as a valuable alternative to surgery.
In the present manuscript, the Authors review the available technologies
intended to treat mitral regurgitation (MR) through transapical
approach, including annuloplasty and chordal repair options.
Annuloplasty: To date, Valcare Amend is the only transapical
mitral valve (MV) ring to have been implanted in patients. The device
allows for stabilization of the annulus through a complete semirigid
D-shaped ring. The first-in-human successful procedure was performed in
2016 by our Group and subsequent clinical experience included a total of
14 implanted patients. Currently the technology is under clinical trial
evaluation to validate the efficacy and safety profile of the device.
Chordal Repair: Beating heart chordal implantation via
trans-apical approach is a current feasible, safe and reproducible
option. Neochord DS1000 is the most widely used technology in the field,
with a solid procedural experience and good results in well-selected
patients. Its clinical use has been validated in Europe since 2012,
while it is still under clinical investigation in the United States.
Harpoon TDS-5 system is a novel technology, recently CE mark approved
for clinical use.
Conclusions: Transapical micro-invasive technologies are current
viable therapies to treat MR in selected patients. Embracing
transcatheter MVRe therapies should guide the cardiac surgeon through
the new revolution of micro-invasive MV tailored repair.
Introduction
Mitral valve regurgitation (MR) affects more than 4 million people in
the United States (US) and Europe, with an incidence of 1-2% of the
western population. Its prevalence increases with age, affecting up to
10% of the population above 75 years11Nkomo VT, Gardin JM,
Skelton TN, et al. Burden of valvular heart diseases: a
population-based study. Lancet 2006;368:1005-11.
10.1016/S0140-6736(06)69208-8.
According to current American and European guidelines, surgery is the
gold standard therapy to treat MR in symptomatic patients, supporting
surgical repair over replacement
with extracorporeal circulation whenever possible
22Authors/Task Force
Members:, et al. ”2017 ESC/EACTS Guidelines for the management of
valvular heart disease.” European journal of cardio-thoracic
surgery 52.4 (2017): 616-664.. Despite MR represents the most
frequent valvular heart disease requiring surgery in the US and the
second most common in Europe33Enriquez-Sarano, Maurice, Vuyisile
T. Nkomo, and Hector I. Michelena. ”Mitral regurgitation.” Valvular
Heart Disease. Humana Press, 2009. 221-246., up to one third of
patients with severe MR are never referred and nearly half are denied
for surgery because of prohibitive risk due to age and
comorbidities44Vesely MR, Benitez RM, Robinson SW, et al.
Surgical and Transcatheter Mitral Valve Repair for Severe Chronic
Mitral Regurgitation: A Review of Clinical Indications and Patient
Assessment. J Am Heart Assoc 2015;4. doi: .10.1161/JAHA.115.002424.
Moreover, by 2030, the increase of the population age will translate in
an estimated increase of 50% in heart failure prevalence, resulting in
a significantly higher rate of MR, especially due to functional
mechanisms55Udelson JE, Stevenson LW. The future of heart
failure diagnosis, therapy, and management. Circulation. (2016)
133:2671–86. 10.1161/CIRCULATIONAHA.116.023518. Therefore, new
less-invasive therapies are needed to further expand the slice of
population to be treated.
Recently a new concept of micro-invasive cardiac surgery has been
introduced to identify a revolutionary group of techniques requiring
neither cardiopulmonary bypass nor aortic cross-clamping66D’Onofrio
A, Gerosa G. Shifting a paradigm of cardiac surgery: from minimally
invasive to micro-invasive. J Heart Valve Dis. 2015. 24: 528-30..
This evolution in technologies allows for off-pump, beating heart
procedures, with a very small skin incision or even totally
percutaneously performed, often requiring limited anesthesiologic
support, with the contribution of multimodality imaging77D’Onofrio
A, Gerosa G. Technique versus technology and the (r) evolution of
cardiac surgery: a professional journey from classical surgery to
embracing intervention. European Journal of Cardio-Thoracic Surgery.
2017. 52.5: 835-837.. Transcatheter aortic valve replacement
represents the clearest example of such micro-invasive procedures. In
the very near future these emerging therapies will likey have a central
role, especially in the high-risk patient population, in both
degenerative and functional MR treatment, despite only weak
recommendations are given for their use by current guidelines (COR IIb,
LOE C)2.
Nowadays the interest of the cardiac surgeon community towards new
micro-invasive procedures is abruptly expanding with the potential to be
adopted as a valuable alternative to conventional surgery, even if, as
far as MVRe is concerned, there are still limitations that need to be
overcame. Once the MV is reached by the use of transapical or
transfemoral puncturing, these technologies can often perform just a
single repair technique, acting on a specific component of the mitral
apparatus (chordae OR leaflets OR annulus), in contrast to surgical
repair, that allows for combined multi-target procedures (chordae AND
leaflets AND annulus). Nevertheless, simultaneous implantation of
different devices has already been reported in well-selected patients,
even if more data are needed to validate the practice88Colli A,
Raanani E, Cobiella J, Wrobel K, Nombela L, Maroto L, et al.
Transapical and transfemoral combined mitral valve repair with annular
and leaflet therapies. The Annals of Thoracic Surgery. 2020..
In the present manuscript, we aim to review currently available
technologies intended to treat MR through a micro-invasive transapical
approach, including annuloplasty and chordal repair options.