Q&A: Clinically defining atrial fibrillation

Q: Our facility is developing clinical definitions regarding types of atrial fibrillation (afib) given the specificity changes in ICD-10. Could you provide suggestions for these definitions? Do you think is it appropriate to query for persistent atrial fibrillation for the period of more than seven days and chronic afib sustained more than 12 months’ duration? Are you aware of any strategies other institutions are using when querying regarding atrial fibrillation?

A: The most recent clinical definitions of afib are:

• Persistent afib is rate and rhythm control focus with afib sustained more than seven days
• Permanent and chronic as defined.

It can be difficult to know when the physician focused treatment on rate control only from a rate and rhythm approach. Not all afib sustained more than seven days is persistent, as it may be permanent. So, to answer your question, using the timeframes of seven days to more than 12 months should not be the only criteria for a diagnosis of persistent afib, because permanent may also fall in that timeframe, too. Certainly, you could ask each clinician to clarify, but such queries may have limited efficacy.

The best approach is to involve your physician advisor or cardiologist to help the CDI team understand the local medications or typical practice patterns they use to address afib and incorporate it into the query process. Unless your inpatient medical record is shared with the ambulatory one, it is hard to get a feel for how the decision may be made.

One key is the use of anti-arrythmic medications, such as flecanide, amiodarone, ibutilide, and digoxin. These give you a hint that the physician is dealing with persistent afib, as there is an interest in rhythm and rate control. However, due to intolerance, medications like diltiazem, metoprolol, digoxin (which is also an anti-arrhythmic) can be used for rhythm control, too, but mostly these are for rate control only.

Not to make it more complex, but recent literature, in some instances, does not support rhythm control and only supports rate control for no change in outcomes.

As a hospitalist in clinical practice, I find this difficult to really standardize with general recommendations as it is a clinical decision of the cardiologist. If they are not documenting the detail, you may not know.

The only other comment I have is regarding postoperative afib. I would not strictly employ an absolute timeframe as the only criteria for post-op afib. I would make sure it meets the definition as a complication of care and not an expected occurrence. For example, 85-90% of all coronary artery bypass grafting and open value procedures have afib. It is not a complication, but expected due to the incision of the epicardium and myocardium and disruption of conduction system.

Remember, all things post-op are not complications of care, and physicians use the term “postoperative” as a temporal description only. The index assumes “postoperative” is a complication of care. I encourage physicians to avoid the word “postoperative” unless they mean a cause-and-effect relationship of the condition being described as a complication.

I hope this provided some insight, but I encourage you to now go to your own cardiologists and ask them to explain the importance and understand practice patterns in your institution.

Editor’s Note: ACDIS Advisory Board Member, James P. Fee, MD, CCS, CCDS, Vice President at Enjoin, answered this question. Contact him at james.fee@enjoincdi.com.