Purpose: Cardiac radio-ablation (CRA) target delineation and planning process evaluation using a novel multimodal 3D cardiac segmentation software.
Methods: In this 3D-EAM-based workflow, the EP delineates the target on the epicardial surface of the left ventricle in the treatment planning interface of the proprietary software MUSIC (Liryc, Bordeaux, Fr). To guide the EP in the delineation process, the electroanatomic mapping (EAM) and cardiac- and fibrosis-segmented contrast-enhanced cardiac CT are in the same frame-of-reference. The resulting target is transmurally expanded and exported as a Dicom RT structure set in registry with the cardiac CT. In the subsequent planning process, the cardiac CT is registered with the planning CT to guide the ITV- and PTV delineation followed by treatment plan optimization. This 3D-EAM-based target delineation workflow replaces the axial-view-based targeting approach for CRA which relies on target delineation on CT scans without EAM data and fibrosis data being in registry. To quantify the time- and cost savings of our 3D-EAM-based workflow, we compared it to a previously performed time-driven activity-based costing (TD-ABC) analysis of the axial-view-based workflow.
Results: The 3D-based targeting approach takes advantage of the EP’s expertise and knowledge of the VT site. It removes the need for (i) the mental abstraction of the target from 3D to 2D, (ii) the use of external software to manually transfer EAM mapping and fibrosis segmentation to the treatment planning system (TPS), (iii) numerous follow-up consultations (further reducing total coordination efforts). Thus, the targeting process is more time-efficient and subject to less variability. TD-ABC demonstrates saving in overall procedural costs of 10.62% ($1234.07), 7.25% ($767.96) and, 8.80% ($909.45) for the so far evaluated cases .
Conclusion: The proposed workflow improves the time-efficiency and reliability of the targeting and planning process, leading to a much more streamlined workflow for CRA.