Atrial fibrillation (AF) is a cardiac disorder. It is the most common type of arrhythmia causing an irregular heat beat, weakness, fatigue and dizziness. AF is associated with increased risk of mortality, stroke and heart failure. AF and heart failure may share common triggers and treatment strategies. We have identified activation of PI3K as a novel strategy for the treatment of heart failure. This project will explore whether increasing PI3K or novel targets of PI3K in the heart of mouse models with AF (using adeno-associated viral vectors or novel compounds) will protect the heart against AF.