Fluoroscopic Overlay of Landmarks from Pre-procedural CT Images after 2D3D Image Fusion to Optimize Trans-septal Access During Percutaneous Mitral Interventions

ABSTRACT

Background: Recent evolution of transcatheter mitral devices and interventions has mandated the need for further optimizing trans-septal access technique with respect to its precise location and distance from the mitral valve annulus.

Methods: Based on the individual procedural context, “ideal” trans-septal access site was planned in multi-slice CT images. In addition, relevant landmarks such as mitral annulus, para-valvular leak site, left atrial appendage (LAA) ostium were electronically marked. CT-fluoroscopy image fusion was performed using a commercially available software after acquiring two fluoroscopic images at-least 30° apart. Manual refinement of image fusion was performed by aligning structures such as a prosthetic valve or mitral annular calcification, when necessary.

Results: Between June and October 2016, a total of five procedures (n = 3 Mitral paravalvular leak, n = 2 Mitraclip®) were performed in four patients using trans-esophageal echocardiography (TEE) and CT image fusion guidance. Fluoroscopic overlay of landmarks including the optimal trans-septal puncture site from pre-procedural CT images was feasible in all five procedures. Median time for CT-fluoroscopy image fusion was 4:08 minutes. Median time for left atrial access was 7:00 minutes. Median (range) fluoroscopy time and total procedural dose-area-product were 29.9 minutes (15.1–77.5) and 16,638 microGy-m² (9464–18,990) respectively.

Conclusion: In addition to real-time TEE imaging, pre-procedural CT planning, image fusion and overlay of relevant landmarks enhances 2D fluoroscopy and provided additional 3D image guidance. Seamless integration of such multi-modality image information can help further optimize steps such as trans-septal access for complex mitral interventions.

KEYWORDS:

• CT fluoroscopy overlay
• image fusion
• mitral valve
• paravalvular leak
• percutaneous mitral valve repair
• trans-septal access

Disclosure statement

JMN and CMB have no relevant disclosures. PC receives support in the form of salary from Siemens Medical Solutions USA Inc.