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Physicians: .25 AMA PRA Category I CreditsTM
Family Physicians: .25 Prescribed credits
Nurse Practitioners: .25 Contact hours

Release Date: November 26, 2014
Expiration Date: November 26, 2015

Estimated Completion Time: 15 minutes

There is no fee for this activity.

To Receive Credit

In order to receive your certificate of participation, you should read the information about this activity, including the disclosure statements, review the entire activity, take the post-test, and complete the evaluation form. You may then follow the directions to print your certificate of participation. To begin, click the CME icon above.

Program Overview

Learning Objectives

Upon successful completion of this educational program, the reader should be able to:

1. Discuss the significance of this article as it relates to your clinical practice.
2. Be able to apply this knowledge to your patient's diagnosis, treatment and management.

Faculty Information

Alan Ehrlich, MD
Assistant Professor in Family Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA; Executive Deputy Editor, DynaMed, Ipswich, Massachusetts, USA

Michael Fleming, MD, FAAFP
Assistant Clinical Professor of Family Medicine and Comprehensive Care, LSU Health Science Center School of Medicine, Shreveport, Louisiana, USA; Assistant Clinical Professor of Family Medicine, Department of Family and Community Medicine, Tulane University Medical School, New Orleans, Louisiana, USA; Chief Medical Officer, Amedisys, Inc. & Antidote Education Company


Dr. Ehrlich, Dr. Fleming, DynaMed Editorial Team members, and the staff of Antidote Education Company have disclosed that they have no relevant financial relationships or conflicts of interest with commercial interests related directly or indirectly to this educational activity.

No commercial support has been received for this activity.

Accreditation Statements

ACCME: This activity has been planned and implemented in accordance with the Essential Areas and policies of the Accreditation Council for Continuing Medical Education through the joint sponsorship of Antidote Education Company and EBSCO Publishing. Antidote is accredited by the ACCME to provide continuing medical education for physicians. Antidote Education Company designates this enduring activity for a maximum of 0.25 AMA PRA Category 1 CreditsTM. Physicians should only claim credit commensurate with the extent of their participation in the activity.

AAFP: This enduring material activity, DynaMed EBM Focus Volume 9, has been reviewed and is acceptable for up to 15.25 Prescribed credits by the American Academy of Family Physicians. AAFP certification begins March 5, 2014. Term of approval is for one year from this date. Each EBM Focus is approved for .25 Prescribed credits. Credit may be claimed for one year from the date of each update. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

AANP: This program is approved for 0.25 contact hour(s) of continuing education by the American Association of Nurse Practitioners. This program was planned in accordance with AANP CE Standards and Policies and AANP Commercial Support Standards.

Program ID: 1405237B2

Last week 553 journal articles were evaluated via DynaMed's Systematic Literature Surveillance and summaries of 197 articles were added to DynaMed content.

Based on criteria for selecting "articles most likely to change clinical practice," one article was selected by the DynaMed Editorial Team.

Percutaneous Closure of Left Atrial Appendage May Decrease the Risk of Death and Hemorrhagic Stroke Compared to Warfarin in Patients with Nonvalvular Atrial Fibrillation
Reference: JAMA 2014 Nov 19;312(19):1988 (level 2 [mid-level] evidence)

Atrial fibrillation affects 1.5-2% of the general population and is associated with a five-fold increased risk of stroke (Eur Heart J 2012 Nov;33(21):2719). Antithrombotic therapy is consistently recommended for most patients with atrial fibrillation and until recently warfarin, a vitamin K antagonist, has been the antithrombotic of choice (J Am Coll Cardiol 2014 Mar 28 early online, Eur Heart J 2010 Oct;31(19):2369, Can J Cardiol 2012 Mar-Apr;28(2):125). Warfarin use requires monthly blood monitoring and is associated with an increased risk of bleeding. The left atrial appendage has been suggested as a major source of thromboembolism in patients with atrial fibrillation and left atrial appendage closure without long-term antithrombotic therapy may prevent stroke (Circulation 2002 Apr 23;105(16):1887). The PROTECT AF trial compared percutaneous device closure of left atrial appendage vs. warfarin in 707 patients with nonvalvular atrial fibrillation plus ≥ 1 risk factor for stroke including age ≥ 75 years, history of previous stroke or transient ischemic attack, hypertension, diabetes, heart failure, or left ventricular systolic dysfunction (Lancet 2009 Aug 15;374(9689):534). A four year follow-up of the PROTECT AF trial was recently published, providing long term efficacy and safety data.

In the PROTECT AF trial, patients randomized to left atrial appendage closure initially continued taking warfarin and aspirin to promote device endothelialization. At 45 days after the procedure, 86.8% of patients receiving device closure were able to discontinue warfarin and 93.2% discontinued warfarin within 1 year. After randomization, 8.2% of patient did not receive the intervention to which they were randomized and 15% of patients withdrew or were lost to follow-up before the 4 year evaluation, but all patients were included in analysis. Comparing device closure vs. warfarin over a mean follow-up duration of 3.8 years (2,621 patient-years), device closure was associated with a decreased risk of hemorrhagic stroke (0.2 per 100 patient-years vs. 1.1 per 100 patient-years, p < 0.05), cardiovascular or unexplained death (1 per 100 patient-years vs. 2.4 per 100 patient-years, p < 0.05), and all cause mortality (3.2 per 100 patient-years vs. 4.4 per 100 patient-years, p = 0.04). No significant differences were observed in rate of any stroke, ischemic stroke, or adverse events.

The results of this trial suggest that left atrial appendage device closure appears as effective as anticoagulation with warfarin for preventing ischemic stroke and may improve both cardiovascular and overall mortality while reducing the risk of hemorrhagic stroke. The initial trial report found that device closure had more adverse events than warfarin, but most adverse events related to device closure occurred in the periprocedural period, while adverse events associated with warfarin occurred throughout the follow-up period. Therefore, over 4 years of follow-up, the rate of adverse events evened out between the two interventions. Device closure may be especially appealing for patients with increased bleeding risk and patients unable or unwilling to follow the monthly monitoring routine required with warfarin use. However, the results of this trial cannot be extended to novel Factor II and Xa inhibitors and further studies are required to determine the efficacy of percutaneous left atrial appendage closure compared to these newer drug therapies.

For more information, see the Atrial fibrillation and Prevention of stroke topics in DynaMed.

DynaMed Careers

The DynaMed editorial team is seeking specialist editors in the following fields: ENT, Gastroenterology, Hematology, Oncology (especially Breast cancer, Head and neck cancer, Pancreatic cancer), Ophthalmology, Orthopedics, Pediatric Endocrinology, Pediatric Neurology, and Vascular.

If interested, please send a recent copy of your CV to Rachel Brady at rbrady@ebsco.com.

PEMSoft Mobile

Free Trial of PEMSoft Mobile Available For iPhone, iPad, and Android Devices

The PEMSoft Mobile app, a pediatric evidence-based point-of-care medical reference tool for hospitals, emergency departments, clinics, pediatric group practices, transport services, and medical schools, is now available from EBSCO Health. Designed by pediatricians, emergency physicians and other medical specialists, the vast content in PEMSoft addresses the entire spectrum of neonatal, infant, child, adolescent and young adult health. PEMSoft authors adhere to a strict evidence-based editorial policy focused on systematic identification, evaluation and consolidation of practice-changing clinical literature.

Content in the PEMSoft Mobile app covers more than 3,000 conditions and includes a similar number of medical illustrations, clinical images and videos. PEMSoft Mobile also includes explicit step-by-step emergency critical care procedures, information about common pediatric signs and symptoms, and topics covering pediatric injuries and management approaches.

Visit the PEMSoft Mobile App Trial page to access a free trial for both Apple and Android devices.

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Click here to speak with us about becoming a peer reviewer.