Atrial fibrillation (AF) continues to be the most frequently occurring arrhythmia in clinical practice. Its presence increases the risk of stroke, heart failure and all-cause mortality. In 2006, ACC/AHA/ESC practice guidelines were published for the management of AF.¹ This was the first step of a multifaceted plan for improving the quality of care delivered to this high-risk group. The second step is the development of performance measures. A review of the recently published performance measures document follows.

       The ‘ACC/AHA/Physician Consortium 2008 Clinical Performance Measures for Adults with Nonvalvular Atrial Fibrillation or Atrial Flutter: A Report of the American College of Cardiology and the Physician Consortium for Performance Improvement (Writing Committee to Develop Clinical Performance Measures for Atrial Fibrillation) Developed in Collaboration with the Heart Rhythm Society’ document was published in the Journal of the American College of Cardiology in February.² The writing committee included senior clinicians, specialists in cardiac electrophysiology, and representatives from the American College of Cardiology, the American Heart Association, the European Society of Cardiology, the American Medical Association, the American College of Physicians, and the Heart Rhythm Society. The clinical population for whom the performance measures were written includes those 18 years or older with nonvalvular AF seen in outpatient settings. The measures are not meant for those with acute, reversible causes of AF or flutter, those with mitral stenosis or prosthetic heart valves, or those who are pregnant.

The Process
       The process used by the group for developing performance measures involved multiple stages. First AF and atrial flutter were defined for the purposes of this measure. Then there was a determination of dimensions of care to be evaluated, categorization of performance measures within the relevant dimensions of care, and identification of areas where evidence was lacking. Extensive literature review was utilized throughout the process. Prevention of thromboembolism was selected as the focus for this set of performance measures.
       The population chosen for this performance measure was patients aged 18 or older with nonvalvular AF or atrial flutter. The performance measurement set for this group includes: assessment of thromboembolic risk factors, chronic anticoagulation therapy, and monthly INR measurement. A sample data collection instrument is available with this document, and the entire document may be downloaded from the American College of Cardiology website at www.acc.org.

Assessment of Thromboembolic Risk Factors
       The assessment of thromboembolic risk is guided by use of the CHADS2 index. This index utilizes a point system to derive a designated risk level for thromboembolism for a given patient. Factors incorporated into this scoring are previous stroke or TIA (a high risk factor), history of hypertension, heart failure or impaired left ventricular systolic function, age of > 75, and diabetes mellitus. Factors other than stroke/TIA were considered moderate risk factors.

Chronic Anticoagulation Therapy
       Determination of appropriate anticoagulation therapy is based on each individual’s assigned risk score. The 2006 guidelines broke this into three levels: low, intermediate, and high risk. Those with low risk had no identified risk factors from the CHADS2 assessment, and the recommendation was that these patients should receive 81–325 mg of aspirin daily. The intermediate risk patient had one moderate risk factor, and was to be placed on aspirin (81 to 325 mg daily) or warfarin (INR 2.0 to 3.0, target 2.5). High-risk patients were those with any high-risk factor or more than one moderate risk factor. Recommended therapy for this group is warfarin (INR 2.0 to 3.0, target 2.5).

Monthly INR Measurement
       The measurement of INR on a monthly basis for those on warfarin is included in the 2006 guidelines. The performance measure data collection tool includes columns for monthly recording of the date of INR, INR value, current warfarin dose, and review of concurrent medications.
       The performance measures for AF and atrial flutter and the tool provided for measurement of these elements within the clinical practice setting represent an effort to continually improve the care we deliver to this population. The committee recognized within their document that 100% compliance can probably never be achieved; however, they have provided an instrument that will help the clinician assess where their practice is and attain a method for evaluating improvement.

For more information about these guidelines, please see: http://content.onlinejacc.org/cgi/content/full/51/8/865