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Objectives: This study aimed to assess the hypothesis that mitral annular disjunction (MAD) is associated with abnormal annular dynamics due to decoupling of annular-ventricular function., Background: MAD, defined as a separation between the atrial wall-mitral valve (MV) junction and left ventricular (LV) attachment, is a structural abnormality occurring in MV prolapse (MVP). Few data exist on the 3-dimensional (3D) geometry of MAD and its functional implication., Methods: A total of 156 subjects including 101 MVP patients (58 ± 11 years), 30 subjects with normal MV (57 ± 15 years), and 25 heart failure patients with functional mitral regurgitation (66 ± 10 years) were studied using real-time 3D transesophageal echocardiography. The spatial relation between atrial wall, MV, and LV attachment was examined for MAD. The 3D extent of MAD and annular dynamics were quantitatively assessed. The LV global longitudinal strain and basal circumferential strains were measured by speckle tracking echocardiography., Results: MAD was evident in 42 MVP patients (42%), measuring 8.9 mm (6.3 to 10.7 mm), circumferentially spanning 87 ± 41°. Dynamically, normal and nondisjunctive annulus contracted and increased in a saddle shape during systole. In heart failure patients with functional mitral regurgitation, mitral annulus was dilated and relatively adynamic, probably related to poor LV function. In contrast, disjunctive annulus displayed paradoxical systolic expansion and flattening (p < 0.0001), despite preserved and comparable LV strains with normal patients. The 3D extent of MAD correlated significantly with abnormal annular dynamics and larger regurgitant orifice (p < 0.0001). In MVP patients without MAD, the LV global longitudinal strain correlated inversely with change in height (r = -0.61; p < 0.0001), whereas LV basal circumferential strain correlated with change in area (r = 0.61; p < 0.0001), but not in patients with MAD (p > 0.05)., Conclusions: MAD is a common anatomic abnormality in MVP. The disjunctive annulus is decoupled functionally from the ventricle, leading to paradoxical annular dynamics with systolic expansion and flattening, and may thus require specific intervention., (Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: Quantitative analysis of mitral valve morphology with three-dimensional (3D) transesophageal echocardiography (TEE) provides anatomic information that can assist clinical decision-making. However, routine use of mitral valve quantification has been hindered by tedious workflow and high operator-dependence. The purpose of this paper was to evaluate the feasibility, accuracy and efficiency of a novel computer-learning algorithm using anatomical intelligence in ultrasound (AIUS) to automatically detect and quantitatively assess the mitral valve anatomy., Methods: A novice operator used AIUS to quantitatively assess mitral valve anatomy on the 3D TEE images of 55 patients (33 with mitral valve prolapse, 11 with functional mitral regurgitation, and 11 normal valves). The results were compared to that of manual mitral valve quantification by an experienced 3D echocardiographer and, in the 24 patients who underwent mitral valve repair, the surgical findings. Time consumption and reproducibility of AIUS were compared to the manual method., Results: AIUS mitral valve quantification was feasible in 52 patients (95%). There were excellent agreements between AIUS and expert manual quantification for all mitral valve anatomic parameters (r=0.85-0.99, p<0.05). AIUS accurately classified surgically defined location of prolapse in 139 of 144 segments analyzed (97%). AIUS improved the intra- [intraclass-correlation coefficient (ICC)=0.91-0.99] and inter-observer (ICC=0.86-0.98) variability of novice users, surpassing the manual approach (intra-observer ICC=0.32-0.95; inter-observer ICC=0.45-0.93), yet requiring significantly less time (144±24s vs. 770±89s, p<0.0001)., Conclusion: Anatomic intelligence in 3D TEE image can provide accurate, reproducible, and rapid quantification of the mitral valve anatomy., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Background: Mitral and aortic valves are coupled via fibrous tissue. This coupling is considered to be important for cardiac function before and after mitral valve surgery. The relationship between mitral-aortic coupling and different types of mitral regurgitation (MR) is not completely understood., Methods and Results: Real-time three-dimensional transesophageal echocardiography (RT3D-TEE) was performed in 133 subjects: 30 normal subjects, 15 patients with Carpentier type I MR (annular dilatation and congenital cleft), 40 type II (mitral valve prolapse), 20 type IIIa (rheumatic) and 28 type IIIb (ischemic mitral regurgitation). Custom software was used to track mitral (MA) and aortic annuli (AoA) in 3D space throughout cardiac cycle, allowing measurement of changes in mitral and aortic valve morphology. Normal mitral-aortic coupling is characterized by reciprocal changes in the annular areas throughout cardiac cycle, with systolic reduction of the angle between the two annular planes. In Carpentier type II patients, not only MA but also AoA areas were increased (P < 0.05 vs normal), but the reciprocal pattern of mitral-aortic coupling was preserved. In both type I IMR and IIIb patients, MA and AoA areas were both increased (P < 0.05 vs normal) and the reciprocal behavior of mitral-aortic coupling was lost. Only MA area was increased in type IIIa patients. The extent of mitral-aortic angle reduction during systole was diminished in all 4 Carpentier groups (P < 0.05 vs normal)., Conclusions: Mitral valve diseases may affect normal mitral-aortic coupling and aortic valve function. Different patterns of abnormal mitral-aortic coupling are associated with different Carpentier types of MR.

Introduction: In functional mitral regurgitation (FMR), effective regurgitant orifice area (EROA) displays a dynamic pattern. The impact of dynamic changes of annulus dysfunction and leaflets tenting on phasic EROA was explored with real-time three-dimensional transesophageal echocardiography (RT3D-TEE)., Methods: RT3D-TEE was performed in 52 FMR patients and 30 controls. Mitral annulus dimensions and leaflets tenting were measured throughout systole (TomTec, Germany). Phasic EROA was measured by proximal isovelocity surface area (PISA) method., Results: Mitral annulus had the minimal area and an oval shape with saddle configuration during early systole in controls, which enlarged and became round and flattened towards mid and late systole (P<0.05). In contrast, annulus in FMR was significantly larger, rounder and flatter (P<0.001), which further dilated and became more flattened at late systole (P<0.05 vs control). Leaflet tenting height in FMR decreased in mid systole and remains unchanged towards late systole. The leaflet tenting volume peaked at early and late systole with a mid-systolic trough in both FMR and controls. But tenting volume of patients with FMR was significantly larger than that of controls (all P<0.001 vs control in whole systole). Further analysis demonstrated that early tenting volume (β value=0.053, P<0.05) was a predictor of early EROA, whereas late tenting volume (β value=0.031, P<0.05) and late annular displacement velocity were predictors of late EROA., Conclusions: The early and late peak EROAs of FMR was primarily contributed by tenting volume at early systole and late systole respectively. These findings would be of value to consider in interventions aimed at reducing the severity of FMR., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

The mitral valve (MV) has complex 3-dimensional (3D) morphology and motion. Advance in real-time 3D echocardiography (RT3DE) has revolutionized clinical imaging of the MV by providing clinicians with realistic visualization of the valve. Thus far, RT3DE of the MV structure and dynamics has adopted an approach that depends largely on subjective and qualitative interpretation of the 3D images of the valve, rather than objective and reproducible measurement. RT3DE combined with image-processing computer techniques provides precise segmentation and reliable quantification of the complex 3D morphology and rapid motion of the MV. This new approach to imaging may provide additional quantitative descriptions that are useful in diagnostic and therapeutic decision-making. Quantitative analysis of the MV using RT3DE has increased our understanding of the pathologic mechanism of degenerative, ischemic, functional, and rheumatic MV disease. Most recently, 3D morphologic quantification has entered into clinical use to provide more accurate diagnosis of MV disease and for planning surgery and transcatheter interventions. Current limitations of this quantitative approach to MV imaging include labor-intensiveness during image segmentation and lack of a clear definition of the clinical significance of many of the morphologic parameters. This review summarizes the current development and applications of quantitative analysis of the MV morphology using RT3DE.