Optimising Cardiovascular Outcomes in Patients with Atrial Fibrillation

Atrial fibrillation (AF) is a complex arrhythmia with multifaceted management. This thesis explores ways to improve cardiovascular outcomes in specific AF populations. For those undergoing percutaneous coronary intervention (PCI), it investigates optimal antithrombotic strategies since current recommendations are inadequate. For those undergoing cardiac surgery, it investigates the safety and efficacy of concomitant surgical ablation (SA), which remains underperformed despite recommendations.

The first study assessed 387 patients with AF receiving triple antithrombotic therapy (TAT) with aspirin, a P2Y12 inhibitor and oral anticoagulation (OAC) for 1 month or ≤1 week post-PCI. At 30 days, TAT for ≤1 week (including those receiving no further aspirin post-PCI) was associated with less bleeding despite greater use of ticagrelor/prasugrel but similar ischaemic events versus 1-month TAT.

The second study recruited 39 patients with AF receiving TAT with ticagrelor/prasugrel, TAT with clopidogrel or dual antithrombotic therapy (DAT) with ticagrelor post-PCI. Bleeding time was shorter among patients receiving DAT compared with TAT with ticagrelor/prasugrel. Cyclo-oxygenase-1-dependent platelet aggregation, assessed by light transmittance aggregometry, was higher with DAT compared with both TAT groups. There were no differences in platelet aggregation with adenosine diphosphate and thrombin-receptor-activating peptide or in fibrin clot properties. DAT consisting of ticagrelor and OAC may provide sufficient antithrombotic effect without excessive anti-haemostatic effect.

The third study compared 652 propensity-matched patients with AF undergoing cardiac surgery with or without concomitant SA. Early post-operative complication rates were similar. Ten-year survival was increased for patients in the SA-group compared with the no-SA group but incidence of ischaemic stroke was similar.

In AF patients undergoing PCI, DAT with ticagrelor/prasugrel and DOAC may be a suitable default regimen with acceptable safety and efficacy which should be studied further. In AF patients undergoing cardiac surgery, concomitant SA potentially improves survival without important safety concerns and wider uptake should be encouraged.