Acute Atrial Fibrillation: Embolism Complications Lowered By Avoiding Cardioversion Delay

Dr. Juhani Airaksinen, MD, PhD Heart Center, Turku University Hospital Turku, Interview with:
Dr. Juhani Airaksinen, MD, PhD
Heart Center, Turku University Hospital
Turku, Finland

Medical Research: What are the main findings of the study?

Dr. Airaksinen:  The main result of our study is that the risk of thromboembolic complications in general was low (0.7%). However the risk rose to a 3.7-fold level when the delay to cardioversion exceeded 12 hours. The time-dependent increase in the risk of thromboembolic complications was more pronounced in female patients. In addition, as expected, old age, heart failure and diabetes were the other significant predictors of postcardioversion thromboembolic complications.

Medical Research: Were any of the findings unexpected?

Dr. Airaksinen: The findings in general were not unexpected, since significant activation of platelets and coagulation factors have been observed already after 12 hours of paroxysmal atrial fibrillation and intra-atrial thrombi have been observed in 4% of patients already within the first 48 hours of acute atrial fibrillation.

The steeper time-dependent increase in thromboembolic risk of female patients was unexpected.

Medical Research: What should clinicians and patients take away from your report?

Dr. Airaksinen: Cardioversion of atrial fibrillation carries always a higher thromboembolic risk compared to stable AF, but the risk seems to be minimal if cardioversion is performed within a short (< 12h) duration of arrhythmia.

So, if you decide to proceed to cardioversion of acute atrial fibrillation, you should avoid unnecessary delays to keep the risk of thromboembolism as low as possible. Furthermore, adequate anticoagulation should be provided according to the current guidelines.


Nuotio I, Hartikainen JK, Grönberg T, Biancari F, Airaksinen K. Time to Cardioversion for Acute Atrial Fibrillation and Thromboembolic Complications. JAMA. 2014;312(6):647-649. doi:10.1001/jama.2014.3824.


Last Updated on August 13, 2014 by Marie Benz MD FAAD