Downloaded from http://heart.bmj.com/ on May 15, 2015 - Published by group.bmj.com
Editorial
Not all thromboembolism comes from the left atrial appendage in atrial fibrillation Keitaro Senoo,1 Gregory Y H Lip1,2 Atrial fibrillation (AF) confers a substantial risk of stroke and thromboembolism, which is effectively reduced by oral anticoagulation (OAC), whether as a vitamin K antagonist (VKA, eg, warfarin) or one of non-VKA oral anticoagulants (NOACs). With the use of OACs, the risk of bleeding remains a problem associated with these agents. Thus, a clinical dilemma remains in the optimal management of patients with AF who are at high risk of stroke but have a history of bleeding. Among patients with non-valvular AF, over 90% of the thrombus is formed in the left atrial appendage (LAA).1 Thus, the exclusion of LAA could greatly decrease the risk of stroke in patients with AF, given that blood stasis in a fibrillating LAA is likely to lead to thrombus formation. Interventional devices to occlude the LAA are not ‘new’ and various LAA closure devices have been available for years. More recently, the Watchman (Atritech) and Amplatzer Cardiac Plug (ACP) device (St Jude Medical) are the more widely used ones in clinical practice. The PROTECT AF (Watchman Left Atrial Appendage System for Embolic Protection in Patients with AF) trial was the first prospective randomised controlled trial (RCT) on LAA closure with 707 patients with non-valvular atrial fibrillation.2 This showed that the Watchman device was non-inferior to warfarin in patients with a high risk of thromboembolism for the primary end point, which was a composite of stroke, systemic embolism (SE) and cardiovascular (CV) death with a risk ratio of 0.62 (95% CI 0.35 to 1.25). However, the rate of intraoperative complications (composite of major bleeding, pericardial effusion, procedure related stroke and device embolisation) was relatively high at 8.7%. Also, the mean CHADS2
1
University of Birmingham, Centre for Cardiovascular Sciences, City Hospital, Birmingham, UK; 2Aalborg Thrombosis Research Unit, Department of Clinical Medicine, Aalborg University, Aalborg, Denmark Correspondence to Professor Gregory Y H Lip, University of Birmingham, Centre for Cardiovascular Sciences, City Hospital, Birmingham B18 7QH, UK; [email protected]
830
score (congestive heart failure, hypertension, age, diabetes, history of stroke) was 2.2 in the Watchman device group and only
Editorial
Not all thromboembolism comes from the left atrial appendage in atrial fibrillation Keitaro Senoo,1 Gregory Y H Lip1,2 Atrial fibrillation (AF) confers a substantial risk of stroke and thromboembolism, which is effectively reduced by oral anticoagulation (OAC), whether as a vitamin K antagonist (VKA, eg, warfarin) or one of non-VKA oral anticoagulants (NOACs). With the use of OACs, the risk of bleeding remains a problem associated with these agents. Thus, a clinical dilemma remains in the optimal management of patients with AF who are at high risk of stroke but have a history of bleeding. Among patients with non-valvular AF, over 90% of the thrombus is formed in the left atrial appendage (LAA).1 Thus, the exclusion of LAA could greatly decrease the risk of stroke in patients with AF, given that blood stasis in a fibrillating LAA is likely to lead to thrombus formation. Interventional devices to occlude the LAA are not ‘new’ and various LAA closure devices have been available for years. More recently, the Watchman (Atritech) and Amplatzer Cardiac Plug (ACP) device (St Jude Medical) are the more widely used ones in clinical practice. The PROTECT AF (Watchman Left Atrial Appendage System for Embolic Protection in Patients with AF) trial was the first prospective randomised controlled trial (RCT) on LAA closure with 707 patients with non-valvular atrial fibrillation.2 This showed that the Watchman device was non-inferior to warfarin in patients with a high risk of thromboembolism for the primary end point, which was a composite of stroke, systemic embolism (SE) and cardiovascular (CV) death with a risk ratio of 0.62 (95% CI 0.35 to 1.25). However, the rate of intraoperative complications (composite of major bleeding, pericardial effusion, procedure related stroke and device embolisation) was relatively high at 8.7%. Also, the mean CHADS2
1
University of Birmingham, Centre for Cardiovascular Sciences, City Hospital, Birmingham, UK; 2Aalborg Thrombosis Research Unit, Department of Clinical Medicine, Aalborg University, Aalborg, Denmark Correspondence to Professor Gregory Y H Lip, University of Birmingham, Centre for Cardiovascular Sciences, City Hospital, Birmingham B18 7QH, UK; [email protected]
830
score (congestive heart failure, hypertension, age, diabetes, history of stroke) was 2.2 in the Watchman device group and only
