Mind the gap: Quantification of incomplete ablation patterns after pulmonary vein isolation using minimum path...

Area of Science:

• Cardiology
• Medical Imaging
• Computational Biology

Background:

• Pulmonary vein isolation (PVI) is a key treatment for atrial fibrillation (AF), aiming to create continuous scar tissue around pulmonary veins.
• Incomplete PVI lesions with gaps are a major cause of AF recurrence, necessitating repeat procedures.
• Current methods like LGE-CMR for gap detection are time-consuming and have high inter-observer variability.

Purpose of the Study:

• To develop and validate a semi-automatic method for identifying and quantifying ablation gaps after PVI.
• To introduce the Relative Gap Measure (RGM) for objective assessment of PVI lesion completeness.
• To analyze population-based gap distribution in the left atrium for improved PVI strategy.

Main Methods:

• A novel semi-automatic approach using graph-based minimum path search to quantify gaps based on scar patch distances.
• Development of the Relative Gap Measure (RGM) to estimate the percentage of gap around each pulmonary vein.
• Evaluation on synthetic data and clinical data from 50 AF patients undergoing radiofrequency PVI.

Main Results:

• The proposed method successfully quantifies ablation gaps, providing an objective measure of PVI lesion completeness.
• Population-based analysis revealed the left superior pulmonary vein is more prone to gaps than the left inferior pulmonary vein (p < .05).
• An advanced RGM integrates data from multiple segmentation techniques for a comprehensive figure-of-merit.

Conclusions:

• The semi-automatic gap quantification method and RGM offer a significant improvement over existing techniques for assessing PVI.
• Findings on regional gap prevalence can guide procedural optimization and improve patient outcomes.
• This approach facilitates objective assessment and potential refinement of PVI interventions.