3D echocardiography in mitral valve prolapse

Abstract

Mitral valve prolapse (MVP) is the leading cause of mitral valve surgery. Echocardiography is the principal imaging modality used to diagnose MVP, assess the mitral valve morphology and mitral annulus dynamics, and quantify mitral regurgitation. Three-dimensional (3D) echocardiographic (3DE) imaging represents a consistent innovation in cardiovascular ultrasound in the last decades, and it has been implemented in routine clinical practice for the evaluation of mitral valve diseases. The focus of this review is the role and the advantages of 3DE in the comprehensive evaluation of MVP, intraoperative and intraprocedural monitoring.

Keywords: mitral annulus (MA); mitral regurgitation (MR); mitral valve prolapse (MVP); mitral valve surgery; percutaneous mitral valve repair; three-dimensional echocardiography (3DE).

Figure 1

Examples of technical evolution of 3D echocardiography. In (A) examples are reported of P2 prolapse by RT 3D TTE (top panel); anterior and posterior leaflet prolapse (arrows) by rotational 3D TEE (bottom panel). In (B) examples are reported of P2 flail by RT 3D TTE (top panel), and P1 flail by 3D RT TEE (bottom panel). In (C) an example is reported of TI rendering: P2 prolapse by 3D TTE (top panel) and by 3D TEE (bottom panel). In (D) an example is reported of the “transparency” effect: P2 flail with a detailed visualization of the ruptured chorda by 3D TTE (top panel); mitral regurgitation color Doppler superimposed to the 3D TEE image (bottom panel). 3D, three-dimensional; RT, real-time. TEE, transesophageal echocardiography; TI, transillumination. TTE, transthoracic echocardiography.

Figure 2

Etiologic phenotypes of mitral valve prolapse. Top panels show examples of fibroelastic deficiency: in (A) P2 prolapse by 3D TTE applying the TI effect; in (B) P2 flail with multiple ruptured chordae by 3D TEE; in (C) P2 flail with single chordal rupture by 3D TEE; in (D) P2 flail with multiple chordal ruptures by 3D TEE. Bottom panels show examples of Barlow's disease: in (E) prolapse of P1–P2–P3 (arrows) by 3D TEE applying the TI effect; in (F) bileaflet prolapse (arrows) by 3D TEE. 3D, three-dimensional; TEE, transesophageal echocardiography; TI, transillumination. TTE, transthoracic echocardiography.

Figure 3

The advantage of transillumination rendering in 3DE. Top panels show an example of P2 flail by 2D TTE with evident eversion of the scallop in a 4-chamber view (A) and in a long-axis view (B). Bottom panels show 3D TTE surgical views of the mitral valve by standard 3D reconstruction (C) and by TI rendering (D). Only TI clearly shows the entire P2 scallop prolapsing in the left atrium with multiple chordal ruptures. 3D, three-dimensional; TEE, transesophageal echocardiography; TI, transillumination. TTE, transthoracic echocardiography.

Figure 4

The role of new 3D tools in echocardiography. Shown are three examples of MVP, in which new tools may improve the quality of imaging. Top panels show a P2 prolapse by standard 3D TTE (A) and by TI rendering (B). Mid panels show a complex P2 prolapse by standard 3D TEE (C) and by TI rendering, which clearly shows the fragile texture of the leaflet (D). Bottom panels show a P2 flail by 3D TEE applying the TI tool (E) and the transparency effect (F). 3D, three-dimensional; Ao, aorta; MV, mitral valve; TEE, transesophageal echocardiography; TI, transillumination. TTE, transthoracic echocardiography; TV, tricuspid valve.

Figure 5

Quantitative modeling of the MV leaflets and annulus by 3DE. Shown is an example of 3D MA reconstruction and semi-automatic computation of 3D MA and leaflets measurements in a case of P2 prolapse. 3DE, three-dimensional echocardiography. MA, mitral annulus.

Figure 6

Examples of surgical mitral valve repair. Top panels show an example of A2 flail with single chordal rupture [arrow, (A)] corrected with the Neochord artificial chordae delivery system (B) obtaining the restoration of normal valve anatomy and competence (C). Bottom panels show an example of multi-scallop prolapse involving A2–P2–P3 with a profound cleft between P2 and P3 (D). The surgical repair was performed with a complete ring device, accurately visualized from the classical atrial perspective in systole (E) and diastole (F).

Figure 7

MitraClip procedure monitoring in a patient with MV prolapse. In (A) TI allows a detailed depiction of the trajectory across the interatrial septum into the left atrium. In (B) the “transparency” effect clearly shows the capture of the MV leaflets by the clip. In (C) TI rendering enhances the visualization the clip before deciding for its release. The lower panels show the result of the procedure. 3D MV reconstruction is displayed by TI rendering from the LA perspective (D), and from the LV perspective with the application of the “transparency” effect, clearly showing 2 clips implanted in the correct position (E). In (F) the residual regurgitant jets are displayed in a 3D reconstruction of the MV with the “transparency” effect and superimposed color Doppler. 3D, three-dimensional; AML, anterior mitral leaflet; Ao, aorta; IAS, interatrial septum; LA, left atrium; LV, left ventricle; MV, mitral valve; TEE, transesophageal echocardiography; TI, transillumination. TTE, transthoracic echocardiography.