This model validates components of the MSKCC model with the addition of platelet and neutrophil counts and can be incorporated into patient care and into clinical trials that use VEGF-targeted agents.

Background-High-frequency fractionated electrograms recorded during atrial fibrillation (AF) in the posterior left atrium (PLA) and elsewhere are being used as target sites for catheter ablation. We tested the hypothesis that highly periodic electric waves emerging from AF sources at or near the PLA give rise to the most fractionated activity in adjacent locations. Methods and Results-Sustained AF was induced in 8 isolated sheep hearts (0.5 mol/L acetylcholine). Endocardial videoimaging (DI-4-ANEPPS) and electric mapping of the PLA enabled spatial characterization of dominant frequencies (DFs) and a regularity index (ratio of DF to total power). Regularity index showed that fractionation was lowest within the area with the maximal DF (DFmax domain; 0.