Three-Dimensional Field Optimization Method: Gold-Standard Validation of a Novel Color Doppler Method for Quantifying Mitral Regurgitation.

Background: Accurate diagnosis of mitral regurgitation (MR) severity is central to proper treatment. Although numerous approaches exist, an accurate, gold-standard clinical technique remains elusive. The authors previously reported on the initial development and demonstration of the automated three-dimensional (3D) field optimization method (FOM) algorithm, which exploits 3D color Doppler ultrasound imaging and builds on existing MR quantification techniques.

Mitral valve annuloplasty and anterior leaflet augmentation for functional ischemic mitral regurgitation: quantitative comparison of coaptation and subvalvular tethering.

Objective: Although restrictive mitral annuloplasty (RMA) has been the preferred surgical treatment of functional ischemic mitral regurgitation (FIMR), some patients with severely dilated left ventricles will experience recurrent mitral regurgitation (MR). Consequently, new surgical strategies have been entertained to compensate for severely dilated ventricles by maximizing coaptation and reducing subvalvular tethering. Anterior leaflet augmentation (ALA) with mitral annuloplasty has been theorized to meet these goals.

Quantitative Evaluation of Annuloplasty on Mitral Valve Chordae Tendineae Forces to Supplement Surgical Planning Model Development.

Purpose: Computational models of the heart's mitral valve (MV) exhibit potential for preoperative surgical planning in ischemic mitral regurgitation (IMR). However challenges exist in defining boundary conditions to accurately model the function and response of the chordae tendineae to both IMR and surgical annuloplasty repair. Towards this goal, a ground-truth data set was generated by quantifying the isolated effects of IMR and mitral annuloplasty on leaflet coaptation, regurgitation, and tethering forces of the anterior strut and posterior intermediary chordae tendineae.

In-vivo mitral annuloplasty ring transducer: implications for implantation and annular downsizing.

Mitral annuloplasty has been a keystone to the success of mitral valve repair in functional mitral regurgitation. Understanding the complex interplay between annular-ring stresses and left ventricular function has significant implications for patient-ring selection, repair failure, and patient safety. A step towards assessing these challenges is developing a transducer that can be implanted in the exact method as commercially available rings and can quantify multidirectional ring loading.

Accuracy of a mitral valve segmentation method using J-splines for real-time 3D echocardiography data.

Patient-specific models of the heart's mitral valve (MV) exhibit potential for surgical planning. While advances in 3D echocardiography (3DE) have provided adequate resolution to extract MV leaflet geometry, no study has quantitatively assessed the accuracy of their modeled leaflets vs. a ground-truth standard for temporal frames beyond systolic closure or for differing valvular dysfunctions.

Mechanics of healthy and functionally diseased mitral valves: a critical review.

The mitral valve is a complex apparatus with multiple constituents that work cohesively to ensure unidirectional flow between the left atrium and ventricle. Disruption to any or all of the components-the annulus, leaflets, chordae, and papillary muscles-can lead to backflow of blood, or regurgitation, into the left atrium, which deleteriously effects patient health. Through the years, a myriad of surgical repairs have been proposed; however, a careful appreciation for the underlying structural mechanics can help optimize long-term repair durability and inform medical device design.

In vitro mitral valve simulator mimics systolic valvular function of chronic ischemic mitral regurgitation ovine model.

Background: This study was undertaken to evaluate an in vitro mitral valve (MV) simulator's ability to mimic the systolic leaflet coaptation, regurgitation, and leaflet mechanics of a healthy ovine model and an ovine model with chronic ischemic mitral regurgitation (IMR).

Methods: Mitral valve size and geometry of both healthy ovine animals and those with chronic IMR were used to recreate systolic MV function in vitro. A2-P2 coaptation length, coaptation depth, tenting area, anterior leaflet strain, and MR were compared between the animal groups and valves simulated in the bench-top model.

Peak mechanical loads induced in the in vitro edge-to-edge repair of posterior leaflet flail.

Background: Percutaneous edge-to-edge mitral valve (MV) repair is a potential therapeutic option for patients presenting with mitral regurgitation, who may not be suitable for surgery. We characterized the edge-to-edge repair forces in a posterior leaflet flail MV model to identify potential modes of mechanical failure.

Methods: Porcine MVs were evaluated in two different sizes (Physio II 32 and 40) in a left-side heart simulator under physiologic hemodynamic conditions.