Comparing efficacy and safety in catheter ablation strategies for atrial fibrillation: protocol of a network meta-analysis of randomised controlled trials oleh Anna Chaimani, Elena Dragioti, Emmanouil Charitakis, Lars O Karlsson, Kostantinos Rizas, Henrik Almroth, Anders Hassel Jönsson, Jonas Schweiler, Skevos Sideris, Dimitrios Tsartsalis