Background: Afib recurrence after single pulmonary vein isolation (PVI) procedure on paroxysmal AF ranges from 38% to 78%. In persistent AF PVI patients, success rate of the initial procedure does not reach 50%. Predictors of response are heavily studied, but currently are incomplete.

Hypothesis: Pulmonary vein area at the ostium are characteristic of a resonance phenomena which relates to success or failure of the PVI procedure.

Methods: Patients (100) with AF who underwent PVI, who had CMR before and 6±2 months after the procedure were retrospectively analyzed. The cross sectional area (CSA) of each pulmonary vein was measured from the 3D MRA of the left atrium and pulmonary veins. Patient response was evaluated using Holter monitoring for 2x15 days post PVI, and characterized as responders (R) if no or less than one minute of AF was experienced or non responders (NR) otherwise. Statistical analysis: Topological cluster analysis was used to order PVI patients: patients were ordered on an organizing variable (average pre PVI PV area) and the average failure rate was calculated. Clusters of size 12 pts were used with an overlap between clusters. Based on the organizing variable, the failure rate for each cluster was plotted, Fig 1. Similar analysis was conducted for data organized on average post PVI PV area.

Results: The topological analysis for the average pre PVI PV area indicated that patients with average PV areas centered around 227 mm2 and 270 mm2 had a worse prognosis, Fig 1A. The topological analysis of the post PV area showed three sharp response regions for PVI failure at 155mm2, 195mm2 and 240mm2, Fig 1B.

Conclusion: Topological analysis reveals sharp resonance conditions that correspond to success or failure of PVI. These resonance states are assessed via average PV area, both pre and post PVI. Further work is needed to explore this phenomenon but topology analysis herein characterizes a heretofore unexpected periodicity in Afib pts uniquely related to PVI success or failure.