Results from the first international multi-center registry of cardiac catheterizations guided with novel three-dimensional image fusion software.

Background
Developments in fusion imaging software have facilitated the use of three-dimensional (3D) roadmaps based on preregistered Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) datasets for guidance of cardiac catheterizations.

Methods
We performed a multi-centre prospective study to evaluate fusion of fluoroscopic two-dimensional (2D) images and the CT or MRI derived 3D roadmaps for guidance of cardiac catheterizations in congenital heart disease. Consecutive patients with pre-existing cross sectional imaging deemed clinically suitable by the operator for VesselNavigator (Philips Healthcare) assisted cardiac catheterization were included in the study. Anonymized data, including pre-catheterization imaging, registration methods, accurateness of overlay, procedural details and overall usefulness of 3D guidance, were collected via a web based application.

Results
From 10/2016 until 12/2018, fusion imaging was applied in 205 patients for guidance (n=182; 88.8%) or planning (n=23; 11.2%) of cardiac catheterization. Previous CT was used in 137 patients (66.8%), an MRI in 68 patients (31.2%). In 176 patients (96.7%) successful 2D–3D registration was performed. In the remaining 6 patients (3.3%) 3D-3D registration was utilized. Accurate initial 3D roadmap alignment was achieved in 142 patients (78%). In 36 patients (19.8%) an unimportant minor mismatch, was observed. Four patients (2.2%) required realignment of the imaging during the procedure. Interventional procedures were performed in 137 patients (75.3%) and 45 patients (24.7%) underwent diagnostic catheterization. In 61 patients (33.5%), catheterization was performed using only 3D guidance; 121 patients (66.5%) required additional angiography. Overall, 3D guidance was deemed useful/very useful in 152 patients (83.5%), essential in 27 patients (14.8%) and not useful/misleading in 3 patients (1.7%).

Conclusions
Direct 2D–3D registration of pre-catheterization imaging is safe and effective method of guidance of cardiac catheterization in congenital heart disease. In selected patients conventional 2D angiography may not be required for procedural guidance.