Comprehensive surgical approach to treat atrial fibrillation in patients with variant pulmonary venous anatomy.

Objectives: Catheter radiofrequency ablation procedures yield fairly successful results for the treatment of atrial fibrillation; however, patients with anatomic variant pulmonary veins (PV) are generally thought not to benefit from catheter ablation technique, with recurrence rates observed as high as 78%. We report a comprehensive surgical approach to treat this subset of patients with a modified full maze procedure.

Methods: From January 2002 to December 2009, 72 patients undergoing cardiac surgery who had drug-refractory and/or recurrent AF after catheter ablation were identified.

The role of approximate entropy in predicting ventricular defibrillation threshold.

Background: The role of myocardial tissue mass on ventricular defibrillation threshold (DFT) is unclear. We hypothesized that changes in tissue mass modulate DFT by changing ventricular fibrillation (VF) wavefront regularity (entropy).

Methods And Results: The right ventricles (RV) of seven farm pigs were isolated, superfused and perfused through the right coronary artery with oxygenated Tyrode's solution at 37 degrees C.