December 15, 2016 – Researchers call for more studies addressing the clinical management of atrial fibrillation while examining the quality of evidence underlying the AHA/ACC/HRS clinical practice guidelines on atrial fibrillation, and how they have changed over time.
A recent study by DCRI researchers and colleagues published online December 14 in JAMA Cardiology describes the changes over time in the joint American College of Cardiology (ACC), American Heart Association (AHA) and Heart Rhythm Society (HRS) guidelines on the management of atrial fibrillation and the distribution of recommendations across classes and levels of evidence.
Both the ACC and the AHA have published clinical practice guidelines on atrial fibrillation, which are used widely to guide patient care in the United States, since 2001. In 2011, the Heart Rhythm Society came on board as a primary author and stakeholder. This study was intended to determine whether there have been meaningful changes in the strength of recommendations and quality of evidence used in the guidelines since 2001.
Classes of recommendations and levels of evidence are organized in a ranking system used in evidence-based practices in medicine to define and denote the strength of the results measured in a clinical trial or research study. Level A recommendations represent the highest quality evidence backed by multiple randomized controlled trials or meta-analyses. This is followed by level B, which represents findings from a moderate-quality trial or analysis, and level C, which is derived from non-randomized, less robust studies.
This study examined recommendations from the AHA/ACC/HRS clinical practice guidelines on atrial fibrillation from 2001, 2006, 2011 and 2014. For each recommendation, the researchers documented class of recommendation, level of evidence, and atrial fibrillation category. Even with a noteworthy increase ( more than 200 percent) in the number of published randomized trials focused on atrial fibrillation between 2001 and 2014, there was no notable change in the use of level A evidence.
“The ACC/AHA/HRS AF Guidelines play a critical role in providing recommendations for the treatment of atrial fibrillation,” said the DCRI’s Jonathan Piccini, MD, MHS, the study’s senior author. “Health systems, practices, and providers use them not only to guide clinical care, but also to help assess quality of care. However, guidelines are only as good as the evidence underlying them. Despite great advances in the treatment of atrial fibrillation, a lot of important clinical questions remained unanswered. For example, rate control – a key component of AF care – does not have any treatment recommendations supported by the highest level of evidence. Thus, as we design new trials in the future, we need to make sure they address practical treatment decisions in a pragmatic way that helps practicing clinicians.”
The researchers also pointed out that the atrial fibrillation guidelines lag when compared to those of other common diseases, such as unstable angina and heart failure, due to the unique challenges posed by the study and treatment of atrial fibrillation. The study did not consider any revisions to the aims and methodology used by ACC/AHA/HRS over the study period and did not use clinical practice guidelines from other organizations, such as the European Society of Cardiology or the American College of Chest Physicians.
These findings, the researchers concluded, do not diminish the value of the AHA/ACC/HRS guidelines but instead highlight the need for additional high-quality studies targeted to specific and pragmatic clinical questions in atrial fibrillation.
In addition to Piccini, other contributing authors included Adam S. Barnett, William R. Lewis, Michael E. Field, Gregg C. Fonarow, Bernard J. Gersh, Richard L. Page, Hugh Calkins, Benjamin A. Steinberg, and Eric D. Peterson.