How much does the presentation pattern of atrial fibrillation affect thrombo-embolic risk and mortality?

Atrial fibrillation (AF) is associated with a substantial increase in mortality and morbidity. Systemic thrombo-embolism is the most serious complication associated with this arrhythmia. The use of anticoagulant drugs is the cornerstone of therapy for the prophylaxis of stroke and peripheral ischaemia in these patients. The current guidelines recommend the use of anticoagulant drugs based on the thrombo-embolic risk profile of each individual patient calculated by SCORE based on the presence or absence of clinical risk factors and regardless of the presentation pattern of AF. A review of literature data investigating the effect of AF presentation pattern on thrombo-embolic risk and mortality showed an increased risk of both thrombo-embolic events and death in patients with non-paroxysmal AF compared to patients with paroxysmal AF. Most of these studies, however, consist of post-hoc analyses of large trials or observational studies and meta-analyses derived from these, resulting in an important limitation in the interpretation of data derived from such studies. At the same time, these data suggest the need for both new therapies to prevent AF progression and for further studies to explore the integration of AF presentation pattern into models of thrombo-embolic risk.