Abstract
The measurement method for the LA wall thickness (WT) using cardiac computed tomography (CT) is observer dependent and cannot provide a rapid and comprehensive visualisation of the global LA WT. We aim to develop a LA wall-mapping application to display the global LA WT on a coplanar plane. The accuracy, intra-observer, and inter-observer reproducibility of the application were validated using digital/physical phantoms, and CT images of eight patients. This application on CT-based LA WT measures were further validated by testing six pig cardiac specimens. To evaluate its accuracy, the expanded maps of the physical phantom and pig LA were generated from the CT images and compared with the expanded map of the digital phantom and LA wall of pig heart. No significant differences (p > 0.05) were found between physical phantom and digital phantom as well as pig heart specimen and CT images using our application. Moreover, the analysis was based on the LA physical phantom or images of clinical patients; the results consistently demonstrated high intra-observer reproducibility (ICC > 0.9) and inter-observer reproducibility (ICC > 0.8) and showed good correlation between measures of pig heart specimen and CT data (r = 0.96, p < 0.001). The application can process and analyse the LA architecture for further visualisation and quantification.
Highlights
The use of cardiac rhythm control medication with catheter ablation is one of the effective ways to treat AF, especially in the early phase[7,8,9,10]
We designed three LA digital phantoms with different characteristic wall thicknesses: a homogenous wall thickness phantom with a wall thickness of 1.0 mm, another homogenous wall thickness phantom with a wall thickness of 2.0 mm, and an inhomogeneous gradient wall thickness phantom whose thickness was 0.5 mm at the LA roof and gradually increased to 1.6 mm at the base. These three phantoms can be directly expanded through image-space transformation, and the global LA wall thickness data can be displayed on a coplanar plane
Comparing the subtracted map and corresponding profile, the distribution of the wall thickness from the computed tomography (CT) measurement is similar to that of the gold standard, whereas the wall thickness at the roof appears to be overestimated. This overestimated is primarily attributed by the partial volume effect (PVE) in the CT images[29] (Fig. 6)
Summary
The use of cardiac rhythm control medication with catheter ablation is one of the effective ways to treat AF, especially in the early phase[7,8,9,10]. In addition to the experience of the physician, the treatment outcome of AF by catheter ablation is closely correlated with the LA electrical-signal distribution and LA architecture[11,12,13]. Diagnostic tools, including cardiac catheterisation, electrocardiography (ECG), electrophysiological study (EPS), magnetic resonance imaging (MRI) and cardiac computed tomography (CT), are needed during the treatment process. Among these tools, cardiac CT is the most popular application for LA surface rendering to provide coarse correlation and localisation for a three-dimensional (3D) EPS map. Intra-observer, and inter-observer reproducibility on studies of LA phantoms and clinical cardiac CT images
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
