Transillumination and Tissue-Transparency Photo-Realistic Echocardiography Imaging During Percutaneous Mitral Valve Interventions

Novel 3D versus traditional transesophageal echocardiography techniques: Defining differences in the diagnosis of infective endocarditis

BACKGROUND

Despite the availability of current antibiotic and surgical treatment options, infective endocarditis (IE) remains associated with a high mortality rate. Even though two-dimensional (2D) transesophageal echocardiography (TOE) is a major criteria in the diagnosis of IE, it is constrained by the single-plane orientation. Since three-dimensional (3D) TOE provides a comprehensive understanding of the cardiac architecture by allowing for a realistic visualization of the underlying structures in 3D space, it has attracted considerable interest in recent years.

AIM

The purpose of this narrative review is to discuss the advantages and pitfalls of 3D TOE in patients with IE, as well as to address emerging photo-realistic 3D techniques that have the potential to enhance the visualization of cardiac structures in this setting.

RESULTS

According to recent research, 3D TOE acquisitions outperform 2D acquisitions in terms of vegetation identification accuracy and embolism risk assessment. By reporting a variety of findings that are missed with 2D TOE, but which are validated by surgical examination, 3D TOE further improves the ability to identify endocarditis complications on both native and prosthetic valves. In addition to conventional 3D TOE, future developments in 3D technology led to the development of transillumination and tissue-transparency rendering, which may improve anatomical understanding and depth perception. Due to the use of both conventional and novel 3D techniques, there are more patients who require surgical intervention, indicating that 3D TOE may have a clinical relevance on the surgical management.

CONCLUSION

3D TOE might fill the gaps left by 2D TOE in the diagnosis of IE.

Clinical Utility of Transillumination on Transthoracic Imaging

• TI is a 3D rendering tool that applies a movable virtual light. • TI may improve anatomic definition and diagnostic yield of transthoracic imaging. • TI is particularly useful for optimal valve anatomy visualization. • New 3D techniques may help achieve TTE images with similar diagnostic yield to TEE.

Advances in Procedural Echocardiographic Imaging in Transcatheter Edge-to-Edge Repair for Mitral Regurgitation

Transcatheter edge-to-edge repair (TEER) therapy is recommended by the American College of Cardiology/American Heart Association (ACC/AHA) guidelines for selected patients with symptomatic severe or moderate-severe mitral regurgitation (MR). Echocardiography, in particular transesophageal echocardiography (TEE), plays a critical role in procedural planning and guidance for TEER. Recent innovations and advances in TEE techniques including three-dimensional (3D) imaging, unlimited x-plane imaging, live 3D multiplanar reconstruction, as well as transillumination imaging with color Doppler and transparency rendering have further enhanced procedural imaging for TEER, especially for complex diseases including commissural defects, clefts, and multi-segment pathologies. This review discusses the technology of these advanced procedural imaging techniques and provides a “step-by-step” guide on how to apply them during the TEER procedure with a focus on their added values in treatment of complex valve lesions.

Unearthing the Tunnel

We present a unique case of a paravalvular leak through a periannular channel around a bioprosthetic mitral valve. The role of multimodality imaging, in addition to novel technology, helped uncover the complex course of the jet, including its origin and direction, which translated into excellent procedural success. (Level of Difficulty: Advanced.)

Utility of transillumination and transparency renderings in 3D transthoracic imaging

Transillumination (TI) is a new 3D rendering tool that uses a freely movable virtual light source to enhance depth, contours, and image detail. The TI model was recently modified to allow the operator adjust the degree of transparency of both cardiac and extra-cardiac structures. While the addition of transparency was shown to significantly improve quality in 3D transesophageal imaging, this has not yet been shown for transthoracic (TTE) imaging. We prospectively studied 35 patients who underwent clinically indicated TTE with standard 3D acquisition, as well as TI with and without transparency. Six experienced echocardiographers were shown images of all three display types in random order. Each image was scored independently using a Likert Scale while assessing each of the following aspects: ability to identify anatomy or pathology, depth perception, degree of anatomic detail, and border delineation. All experts perceived an incremental value of the transparency mode, compared to TI without transparency and standard 3D rendering, in terms of ability to identify anatomy or pathology (4.15 ± 0.97 vs. 3.88 ± 0.99 vs. 2.52 ± 1.41, p < 0.01), depth perception (4.33 ± 0.78 vs. 3.88 ± 0.82 vs. 2.29 ± 1.07, p < 0.01), degree of anatomic detail (4.08 ± 1.0 vs. 3.89 ± 0.79 vs. 2.31 ± 1.08, p < 0.01), and border delineation (4.44 ± 0.80 vs. 3.90 ± 0.78 vs. 2.42 ± 1.13, p < 0.01). Compared to standard 3D and TI renderings of TTE images, the addition of transparency significantly improves both image quality and diagnostic confidence.