Evaluation of the Accuracy and Intraprocedural Use of a Holographic Display for 3-Dimensional Transesophageal Echocardiography

Background: Real-time 3-dimensional transesophageal echocardiography (3DTEE) data acquired during interventional procedures are displayed on 2-dimensional screens, limiting intuitive depth perception and spatial comprehension. The study objectives were to evaluate the feasibility of intraprocedural use of a holography display during structural cardiology procedures employing 3DTEE, and to assess the accuracy of offline linear measurements in 3DTEE datasets. Methods: A prospective single-center study was conducted using the HOLOSCOPE-i to guide catheter-based procedures using intraprocedural 3DTEE. Qualitative measures of recognition of anatomic structures, 3D spatial comprehension, and interaction with intracardiac anatomic structures and catheter position were evaluated using a Likert scale. Additionally, a retrospective analysis of offline 3DTEE datasets of mitral valve measurements were performed using the HOLOSCOPE-i vs QLAB. Intra- and interobserver variability was assessed, assuming an intraclass correlation coefficient > 0.75 indicates adequate reliability. Results: A total of 13 patients were enrolled. In all cases, anatomic structures were identified in real time, and spatial comprehension was enhanced (Likert scale). No nausea or headache was reported by the operators. Retrospective analysis of 41 mitral valve 3DTEE datasets was performed. Annular diameter measurements (anteroposterior [AP] and anterolateral-posteromedial [AL-PM]) demonstrated a Pearson correlation of 0.89 (HOLOSCOPE-i) and 0.91 (QLAB). Intraobserver ICC for AP, AL-PM was 0.97, 0.94 (HOLOSCOPE-i) and 0.95, 0.97 (QLAB); interobserver ICC for AP and AL-PM was 0.77 and 0.88 (HOLOSCOPE-i) and 0.96 and 0.98 (QLAB). Conclusions: Holographic display of intraprocedural real-time 3DTEE data is feasible and augments the experience of the operator. Linear measurements in the 3D holographic display are accurate, with good correlation to those using 2-dimensional multiplanar reconstruction 3DTEE software. Clinical Trial Registration: MOH_2021-09-13_010255.