Atrial Fibrillation Procedure Within Two Years Reduces Risk of Afib Recurrence
October 29, 2009 5:21 AM CT
By Peggy Noonan
Research shows that the sooner atrial fibrillation surgery is done, the less likely AF is to recur.
A study in the European Journal of Cardio-thoracic Surgery reports that those in permanent atrial fibrillation who underwent left atrial ablation surgery in conjunction with surgery for other heart diseases were more likely to be afib-free if they had been in atrial fibrillation less than two years and their left atrium was of normal size.
All study participants had left atrial ablation procedures concomitant (at the same time) with open-heart mitral valve, aortic valve, or coronary artery bypass surgery. The procedures were done using either microwave (Flex 4W, Guidant) or radiofrequency (CardioblateW, Medtronic) energy. Participants were assessed after surgery at 3, 6, and 12 months, and yearly thereafter.
While the rate of conversion to sinus rhythm (SR) was 75% when atrial fibrillation had lasted for less than 2 years, it was only 42% when afib had lasted for longer and the left atrium was also enlarged (>50 mm).
“Out of a huge variety of potential factors examined, only preoperative AF duration and left atrial size were significant determinants for rhythm outcome,” the authors concluded. “Every 1-month increase in AF duration corresponded to an increase in the risk for recurrent AF after surgery of 0.5% and every 1 mm (millimeter) increase in left atrial diameter to a 5.6% increase in the risk.”
The study concluded that concomitant treatment of permanent AF by left atrial ablation should be undertaken early, preferably before it exceeds two years, and if the left atrium is enlarged to more than 50 mm in diameter, a reduction should be considered.
None of the following were found to predict AF recurrence: age, gender, primary heart disease, history of thromboembolism (a clot that blocks a blood vessel) or cardioversion (medication or electric shock to restore normal heart rhythm), type of primary heart surgery performed, ablation technology, or use of antiarrhythmic drugs.
It should be noted that the mean age in this study was almost 70 years, and in the future, cardiac patients will be increasing in age. The authors concluded that “focusing concomitant AF treatment on the left atrium, where the majority of AF is anchored, could be a reasonable way of reducing operative risk, which is higher in old age.”
To read more about the study, see:
- Factors predicting the time until atrial fibrillation recurrence after concomitant left atrial ablation
Peggy Noonan specializes in writing about health for consumers and medical professionals. She writes for leading national magazines and consumer publications as well as StopAfib.org.