February 19, 2014

DynaMed EBM Journal Volume 9, Issue 8

DynaMed Weekly Updates

Quick Links

Join Mailing List



Physicians: .25 AMA PRA Category ICreditsTM

Family Physicians: .25 Prescribed credits

Nurse Practitioners: .25 Contact hours

Release Date: February 19, 2014

Expiration Date: February 19, 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 at the end of the article.

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 Clinical Professor in Family Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA; Senior 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 EducationCompany 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: Enduring Material activity, DynaMed EBM Focus, has been reviewed and is acceptable for up to 13 Prescribed credits by the American Academy of Family Physicians. AAFP certification begins March 7, 2012. Term of approval is for one year from this date with the option of yearly renewal. Each EBM Focus is worth .25 Prescribed credits. 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 of continuing education by the American Academy of Nurse Practitioners.

Program ID: 1304159P


Last week 668 journal articles were evaluated via DynaMed's Systematic Literature Surveillance and summaries of 259 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.

In Adults With Unruptured Brain Arteriovenous Malformation, Interventional Therapy Appears to Worsen Outcomes Compared to Medical Management
Reference: Lancet 2014 Feb 15;383(9917):614 (level 2 [mid-level] evidence)

With the increased use of noninvasive neuroimaging, there has been an increase in the detection of brain arteriovenous malformations prior to symptomatic bleeding, but there is currently no clear consensus for the management of these lesions. Patients diagnosed with unruptured or asymptomatic arteriovenous malformations may be managed conservatively or, alternatively, they may be offered interventional therapy with the aim of obliterating the origin of the arteriovenous malformation. Several interventional therapies, including neurosurgery, embolization, and stereotactic radiotherapy have been used successfully in these patients, but there is little clinical evidence to guide the choice of interventional therapy, or to demonstrate its superiority over conservative management. A prospective population-based cohort study in Scotland previously showed that patients receiving interventional therapy for arteriovenous malformation had worse outcomes than those who did not (Lancet Neurol 2008 Mar;7(3):223). Now, a randomized trial compares the addition of interventional therapy to medical management vs. medical management alone in adults with unruptured arteriovenous malformation.

A total of 226 adults (mean age 45 years) with unruptured brain arteriovenous malformation were randomized to medical management alone vs. medical management plus interventional therapy. Patients, clinicians, and investigators were aware of treatment assignment. Medical management consisted of pharmacologic therapy for existing medical disorders (such as seizures or headaches) or any coexisting vascular risk factors (such as diabetes or arterial hypertension), as needed. Patients randomized to interventional therapy additionally received neurosurgery, embolization, or stereotactic radiotherapy, either alone or in combination, at the discretion of the local trial investigator. Patients with evidence of recent or prior hemorrhage, or who had received previous interventional therapy for brain arteriovenous malformation, were excluded from the trial. The goal of the interventional therapy was complete eradication of the arteriovenous malformation. The primary outcome was a composite of symptomatic stroke or death.

The trial was stopped early by an independent data and safety monitoring board, due to superiority of medical management alone based on a prespecified stopping value for the primary outcome. The interim analysis included 223 patients (99% of those randomized) with a median follow-up of 33 months. Symptomatic stroke or death occurred in 10% of those receiving medical management alone vs. 31% of those receiving interventional therapy plus medical management (p < 0.05, NNT 5). The incidence of stroke was 11% with medical management alone vs. 39% with interventional therapy plus medical management (p < 0.0001, NNT 4). In addition, neurologic deficits unrelated to stroke occurred in 0.9% of those treated with medical management alone vs. 12% of those treated with interventional therapy plus medical management (p = 0.0008, NNT 9).

The results of this trial extend previous findings from an observational study, and further support the conclusion that current interventional therapies for unruptured arteriovenous malformations do not improve cerebrovascular outcomes. However, arteriovenous malformations are associated with a long natural history, and the median follow-up of 33 months included in this trial limits the ability to make conclusions about long-term effectiveness. In addition, by not including patients who had received previous interventional therapy for brain arteriovenous malformation, patients with a more aggressive disease course may have been excluded, and this may therefore limit the generalizability of the findings.

For more information see the Central nervous system vascular malformations topic in Dynamed.

Earn CME Credit for reading this e-Newsletter.
For more information on this educational activity, see the CME sidebar.

Call for Peer Reviews

We are currently seeking subspecialty reviewers for our Patient Education Resource Center (PERC). PERC provides fact sheets and discharge instructions for patients leaving the hospital or emergency room. These hand-outs fulfill the meaningful use requirements for the Medicare & Medicare Services Incentive Programs.

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

DynaMed Careers

Looking for a change? The DynaMed editorial team is expanding and looking for talented and driven individuals. Visit the links below to learn about these exciting opportunities.

Deputy Editor of Oncology
Associate Managing Editor