Tools for AF ablation form a very important part of the procedure and have improved success rates and safety. Intracardiac ultrasound such as the AcuNav™ catheter can be used for placement of transeptal catheters and to monitor the formation of intracardiac clot. Specialised catheters for circumferential mapping of the PVs help delineate the PV ostium and ensure electrical isolation. For patients with self-terminating (paroxysmal) AF, success rates of 80–90% have been established in several large series. For those with permanent AF, the more extensive ablation needed is associated with cure rates of 60–80%.¹² Importantly, those with heart failure – a group with high mortality rates – have been demonstrated to benefit from a reduced mortality rate when undergoing catheter ablation compared with standard medical management.¹³ What limits AF ablation at the present time is the lack of hard end-points for this procedure, as well as incomplete lines of ablation, which may worsen the condition they are trying to treat. Success rates for atrial flutter ablation rose by 60–90% with the realisation of reproducible electrophysiological end-points. The expectation must be that similar improvements will occur in AF ablation.

However, some risks remain with AF ablation, such as the 1% incidence of stroke and cardiac perforation, which restricts its use as a first-line procedure.12 Many patients undergoing cardiac surgery for coronary artery and valvular heart disease have concomitant AF. When the chest is open, surgical ablation of AF adds little mortality or morbidity to the procedure. The sheer number of patients affected by AF and the expensive and time-consuming nature of ablation for AF will restrict its use to those with symptomatic AF who have failed or decline initial medical management.

AF is associated with a doubling of the risk of stroke compared with age- and disease-matched controls.1 Effective treatment in the form of aspirin or anticoagulants is available, but the benefits in terms of stroke prevention need to be balanced against the increased risk of bleeding associated with their use. The increased thromboembolic risk associated with AF arises as a result of stasis of blood in the left atrium, and the left atrial appendage (LAA) in particular.14 Surgeons have routinely removed this area at the time of mitral valve replacement to avoid subsequent thromboembolism. A novel approach is to occlude the LAA percutaneously with a prosthetic device made of nitanol mesh. To date, two small trials – Watchman LAA occluder and percutaneous LAA transcatheter occlusion (PLAATO) device15,16 – have reported showing an absence of stroke in the treated groups and successful occlusion of the LAA at follow-up. This may, in the future, reduce the need for warfarinisation with its attendant risks in a large number of patients.

AF is associated with a doubling of the risk of stroke compared with age- and disease-matched controls.1 Effective treatment in the form of aspirin or anticoagulants is available, but the benefits in terms of stroke prevention need to be balanced against the increased risk of bleeding associated with their use. The increased thromboembolic risk associated with AF arises as a result of stasis of blood in the left atrium, and the left atrial appendage (LAA) in particular.¹⁴ Surgeons have routinely removed this area at the time of mitral valve replacement to avoid subsequent thromboembolism. A novel approach is to occlude the LAA percutaneously with a prosthetic device made of nitanol mesh. To date, two small trials – Watchman LAA occluder and percutaneous LAA transcatheter occlusion (PLAATO) device ^15,16 – have reported showing an absence of stroke in the treated groups and successful occlusion of the LAA at follow-up. This may, in the future, reduce the need for warfarinisation with its attendant risks in a large number of patients.

Summary

AF is a complex and common arrhythmia manifesting in a wide range of cardiac and non-cardiac conditions. Patients experience symptoms of shortness of breath and palpitations, which have a significant impact on quality of life. More concerning is the increased risk of stroke. Attempts to restore sinus rhythm are becoming increasingly successful as a result of refined algorithms for the use of existing drug treatment and the emergence of more atrial-specific agents, which modify substrate and exert specific atrial antiarrhythmic effects free of ventricular pro-arrhythmia. Ablation, using either a surgical or percutanous approach, has a very high success rate for those with paroxysmal AF, although its use as a first-line therapy is limited by the risk of stroke and thoracotomy. Refinements to ablation techniques for permanent AF – such as the use of advanced mapping – are producing encouraging results in terms of restoration of normal rhythm and also in the reduction in the complications associated with AF such as heart failure deaths.