Three-dimensional echocardiography using a muliplane transesophageal probe: the clinical applications

Four-dimensional modelling of the mitral valve by real-time 3D transoesophageal echocardiography: proof of concept

OBJECTIVES

The complexity of the mitral valve (MV) anatomy and function is not yet fully understood. Assessing the dynamic movement and interaction of MV components to define MV physiology during the complete cardiac cycle remains a challenge. We herein describe a novel semi-automated 4D MV model.

METHODS

The model applies quantitative analysis of the MV over a complete cardiac cycle based on real-time 3D transoesophageal echocardiography (RT3DE) data. RT3DE data of MVs were acquired for 18 patients. The MV annulus and leaflets were semi-automatically reconstructed. Dimensions of the mitral annulus (anteroposterior and anterolateral-posteromedial diameter, annular circumference, annular area) and leaflets (MV orifice area, intercommissural distance) were acquired. Variability and reproducibility (intraclass correlation coefficient, ICC) for interobserver and intraobserver comparison were quantified at 4 time points during the cardiac cycle (mid-systole, end-systole, mid-diastole and end-diastole).

RESULTS

Mitral annular dimensions provided highly reliable and reproducible measurements throughout the cardiac cycle for interobserver (variability range, 0.5-1.5%; ICC range, 0.895-0.987) and intraobserver (variability range, 0.5-1.6%; ICC range, 0.827-0.980) comparison, respectively. MV leaflet parameters showed a high reliability in the diastolic phase (variability range, 0.6-9.1%; ICC range, 0.750-0.986), whereas MV leaflet dimensions showed a high variability and lower correlation in the systolic phase (variability range, 0.6-22.4%; ICC range, 0.446-0.915) compared with the diastolic phase.

CONCLUSIONS

This 4D model provides detailed morphological reconstruction as well as sophisticated quantification of the complex MV structure and dynamics throughout the cardiac cycle with a precision not yet described.

Intraoperative application of geometric three-dimensional mitral valve assessment package: a feasibility study

OBJECTIVE

To study the feasibility of using 3-dimensional (3D) echocardiography in the operating room for mitral valve repair or replacement surgery. To perform geometric analysis of the mitral valve before and after repair.

DESIGN

Prospective observational study.

SETTING

Academic, tertiary care hospital.

PARTICIPANTS

Consecutive patients scheduled for mitral valve surgery.

INTERVENTIONS

Intraoperative reconstruction of 3D images of the mitral valve.

RESULTS

One hundred and two patients had 3D analysis of their mitral valve. Successful image reconstruction was performed in 93 patients-8 patients had arrhythmias or a dilated mitral valve annulus resulting in significant artifacts. Time from acquisition to reconstruction and analysis was less than 5 minutes. Surgeon identification of mitral valve anatomy was 100% accurate.

CONCLUSIONS

The study confirms the feasibility of performing intraoperative 3D reconstruction of the mitral valve. This data can be used for confirmation and communication of 2-dimensional data to the surgeons by obtaining a surgical view of the mitral valve. The incorporation of color-flow Doppler into these 3D images helps in identification of the commissural or perivalvular location of regurgitant orifice. With improvements in the processing power of the current generation of echocardiography equipment, it is possible to quickly acquire, reconstruct, and manipulate images to help with timely diagnosis and surgical planning.

The Use of Three-Dimensional Echocardiography for the Evaluation of and Treatment of Mitral Stenosis

To date, mitral stenosis has been evaluated by both hemodynamic data derived from catheterization as well as 2D and Doppler echocardiography. However, the advent of real-time 3D echocardiography has allowed more precise measurement of the mitral valve orifice by planimetry. In addition, evaluation of the mitral commissures prior to and after percutaneous mitral valvuloplasty is greatly aided by 3D echocardiography. Here we discuss these subjects as well as provide specific clinical trials that support the use of real-time 3D echocardiography for the evaluation and treatment of mitral stenosis.

Live three-dimensional paediatric intraoperative epicardial echocardiography as a guide to surgical repair of atrioventricular valves

Real-time three dimensional echocardiography is increasingly used for imaging patients with congenital cardiac malformations. One of the limitations of a transthoracic approach is that intervening structures can impact on the quality of the images obtained. We hypothesised that, during surgery, epicardial three-dimensional echocardiography would provide images of high quality. We report our findings in eight children or young adults, with weights ranging from 2.8 to 70 kilograms, in whom we used this approach. In all cases, we obtained images of good quality, which could be analysed rapidly in the operating room. Of the eight cases, seven had echocardiographic findings which matched exactly the surgical findings. The remaining child had been diagnosed echocardiographically with a cleft in the aortic leaflet of the mitral valve, but was found at surgery to have a double orifice in the valve.

Evaluación de la severidad y decisiones quirúrgicas en las valvulopatías

A better knowledge of the natural history of valvular disease and the advances in surgical techniques are allowing to improve the prognosis of patients with valvular heart disease. At present, imaging techniques, particularly Doppler-echocardiography, is the main tool to determine the diagnosis and prognosis of patients with valvular heart disease. Consequently, decision making in valvular heart disease is now days based on a combination of symptomatic status and echocardiographic findings. The main applications of Doppler-echocardiography with this purpose are summarized in this article. Therapeutic algorithms for patients with valvular heart disease are proposed, as well as the potential application of new imaging modalities appeared in the last years. The state of the art of clinical practice guidelines are also reviewed.