O ral anticoagulation is the standard of care for stroke prevention in atrial fibrillation but falls short of providing an adequate solution to this common threat when considered from both efficacy and safety perspectives. Anticoagulationassociated treatment deficits include major and minor bleeding, refusal of anticoagulation based on anticoagulation risk, lack of medication adherence, personal and physician preference, and a persistent risk of ischemic stroke and major adverse cardiovascular events despite use. The challenges of contemporary anticoagulation management are highlighted in a recent large national assessment of warfarin therapy use involving 138 319 patients and 2 683 674 international normalized ratio results with reported mean time in therapeutic range of only 53.7%.1 Even in the setting of optimal management without clinically relevant major bleeds, emerging data regarding long-term risk of cerebral microbleeds prompt the need to explore risk and benefits of long-term anticoagulation use in patients with atrial fibrillation.
Response by Ezekowitz and Kent on p 1524Among atrial fibrillation patients who experience a stroke, the large majority are felt to originate from left atrial appendage (LAA) thromboembolism.4,5 Accordingly, despite the lack of randomized data, LAA ligation is a frequent adjunct to cardiac surgery in patients with atrial fibrillation. Minimally invasive transcatheter occlusion systems are now available and minimize the invasive nature of open and thorascopic surgical approaches. The long-term outcomes from multiple trials using the Watchman LAA occlusion system (Boston Scientific, Natick, MA) have demonstrated that endocardial left atrial appendage closure provides similar protection against stroke, systemic embolism, and cardiovascular mortality as warfarin, and by extension provides proof of concept of LAA closure. LAA closure is an upfront treatment without the bleeding risks inherent to lifelong anticoagulation. As such, with long-term efficacy similar to anticoagulation without the need for chronic drug dependence, percutaneous transcatheter LAA closure meets the tremendous unmet needs of patients with reasons to not take oral anticoagulants.
The Persistent Unmet Needs of Traditional and Novel Anticoagulants Risk of Major and Minor BleedingAnticoagulation therapy use is directed by characterizing an individual patient's stroke risk with either the CHADS 2 or CHA 2 DS 2 -Vasc score. Anticoagulation has traditionally been recommended in patients with a CHADS 2 score ≥2 and selected patients with a CHADS 2 score of 1. More recent guidelines have recommended moving from CHADS 2 to the more accurate