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Page 2 of 17 Melillo et al. Mini-invasive Surg 2020;4:81 I http://dx.doi.org/10.20517/2574-1225.2020.83

INTRODUCTION
The burden of clinically significant mitral valve disease is noteworthy in the elderly population and
therapeutic options were constrained due to patients’ high operative risk so far. Thanks to new transcatheter
mitral valve (MV) therapies, alternatives to surgical and medical treatments are now available. Accurate
patient selection is crucial for procedural success and is based on careful preprocedural multimodality
imaging evaluation. Echocardiography, cardiac magnetic resonance (CMR), and cardiac computed
tomography (CT) may provide complementary information to guide patient and device selection.
Evaluation of mitral valve anatomy, identification of MV lesion, and quantification of defect severity should
be integrated by comprehensive preprocedural assessment of chamber size, biventricular systolic and
diastolic function, hemodynamic impact, and aortic or peripheral vascular disease. The aim of this review
is to provide an overview on the role of multimodality imaging in the patient selection and preprocedural
planning of percutaneous mitral valve repair.

ECHOCARDIOGRAPHY
Echocardiography is pivotal for diagnosis, anatomical and functional characterization, and quantification
of mitral regurgitation (MR) severity. Transthoracic echocardiography (TTE) is the first level imaging
modality and allows a comprehensive evaluation of valve disease, chamber size, and function. Evaluation
of mitral and pulmonary flow pattern as well as pulmonary artery pressure and chamber dimensions are
precious indexes of hemodynamic load secondary to the valvopathy. Transesophageal echocardiography
(TEE) is a second level imaging modality, and it is usually indicated for a deep evaluation of valve anatomy
and MR grading. 2D echo allows both morphological and functional evaluation of the MV: the former
is based on detection of leaflet abnormalities such as thickness, redundancy, and calcification, as well
as identification of annular calcification, and the latter is based on evaluation of systo-diastolic leaflet
motion according to Carpentier classification and is fundamental to understand the disease etiology and
to guide the therapeutic strategy. 3D echocardiography (3DE) provides an added value in detailing MV
morphology and precise localization of pathology through 3D rendering, multiplanar reconstruction
(MPR), and 3D color-Doppler. 3D rendering is pivotal for morphological assessment as it provides a more
[1]
realistic representation of the MV, which can be visualized through several perspectives . Moreover, 3DE
[2]
is superior to 2D echo in detailing the lesions in terms of scallop disease and commissural involvement
and localizing the calcifications and additional findings such as clefts or tissue deficiency. The MPR
[3]
mode allows the assessment of annular dimensions and its dynamics during the cardiac cycle , mitral
valve area (MVA), and characterization of the disease (flail/prolapse detection, localization, and analysis)
[Figure 1]. Furthermore, it allows studying specific sites of interest such as the potential grasping zone
for transcatheter repair with leaflet approach in terms of measurement of posterior leaflet length, leaflet
motion, and calcification/thickness [Figure 2].

The site of origin of the regurgitant jet may be identified by 3D color-Doppler, especially from the left
ventricular perspective that directly shows the flow convergence area. Moreover, measurement of 3D vena
contracta area is a new method for MR quantification showing higher accuracy compared to 2D color-
[4]
Doppler, particularly in the presence of multiple or eccentric MR jets . Color-coded 3D parametric maps
may be created by either automatic or semiautomatic software, provide indices of MV remodeling, and may
[5]
localize MV pathology .
Finally, 3D transthoracic echo provides reproducible measurement of LV volumes and function with
[6]
similar accuracy compared to CMR .
Speckle tracking imaging represents a more sensitive tool to assess LV dysfunction than ejection fraction
and may improve the selection of candidates for the procedure. Recently, baseline GLS value <-9% has been