Description of the anatomical characteristics of mitral valve apparatus among patients with moderate or severe primary mitral regurgitation using 3D transesophageal echocardiography
Authors: Bitsara M , Zisis M , Patsourakos D , Dimitroglou I , Koukos M , Tsartsalis D , Gialeli F , Kalompatsou A , Papatheodorou E , Tsioufis K , Aggeli C 
Published: January 2025

Abstract

Background/Introduction
There are two types of mitral regurgitation (MR); primary, which is characterized by abnormalities of the mitral valve apparatus and secondary or functional, caused by left atrioventricular remodeling. The implementation of 3D transesophageal echocardiography (3D-TEE) has resulted in the precise depiction of the anatomical characteristics of mitral valve apparatus that prompts appropriate treatment.

Purpose
The aim of this study is to describe the anatomical characteristics of the mitral valve among patients with moderate or severe primary MR by using 3D-TEE.

Methods
From 2017 to 2023, 333 3D-TEE examinations have been performed in our center to evaluate MR cases. Specifically, 181 cases were classified as primary MR (52 moderate and 129 severe), in which visualization of the mitral apparatus had been performed via 3D-TEE. The recorded 3D data were retrospectively analyzed with specialized software and the pathophysiology of MR was described in each case.

Results
The median patient age was 63.9 years (SD±13.5), while 58% of patients were men. The left atrium was moderately or severely enlarged in 79% of the cases and the left ventricular ejection fraction was &gt;60% in 61.5% of the patients. Mitral valve prolapse (MVP) with or without flail was found in 109 (61.9%) patients. Furthermore, it was noticed that MVP had been occurred at the anterior leaflet in 45.5% of the cases, at the posterior leaflet in 25% and at both leaflets in 29.5% of the cases. Moreover, in 65.5% of the cases, one or two mitral valve scallops had been affected. In the MR cases where the predominant pathophysiology was flail valve, the posterior mitral leaflet had been involved in 94.8% of the cases with one or two scallops been affected (83.9%). Among patients with both flail valve and MVP, the former was found at the posterior leaflet, while the latter at the anterior leaflet (in 63.9% of the cases). Mitral valve cleft in the absence of another mitral valve pathology was found in 7 patients (4%), while in 8 patients (4.4%) MVP was present and in 4 cases (2.2%) a combination of MVP and flail was found. The mitral cleft was depicted on P1P2 (38.1%) and P2P3 (23.8%) scallops respectively. Bileaflet cleft was found only in 4.8% of the cases. Moreover, calcified mitral lesions as primary cause of MR were found in 37 patients (21%), while rheumatic mitral valve pathology was found in 13 patients (7.4%). Among the rest causes of MR, infective endocarditis was found in 7 patients (4%) and systolic anterior motion of mitral valve in the context of hypertrophic cardiomyopathy in 3 patients (1.7%).

Conclusions
The description of mitral valve anatomy with the use of 3D-TEE provides useful information regarding morphological features that are used as favorable criteria for mitral valve repair procedures. It is suggested that cardiologists should get familiarized with 3D-TEE aiming at optimal clinical decisions to achieve maximum benefit for the patient.