Long-term Evolution of Patients with Lone Atrial Fibrillation: Is it a Benign Entity?

América Pérez, MD, Miguel Parra-Pavich, MD, Fernando A. Scazzuso, MD, and Jorge González-Zuelgaray, MD.

Argerich Hospital.
Buenos Aires, Argentina.

Abstract
Idiopathic atrial fibrillation (AF) has been associated with a good prognosis. This survey was carried out in order to evaluate the long-term evolution of this entity in patients (pts) from a single institution.
Fifty-four consecutive pts with lone AF, 32 men and 22 women, aged between 15 and 71 years (mean 44.7 ± 15.4) were included. The history of the arrhythmia ranged between 2 and 27 years (mean 9.5 years).
Twenty-two pts (43%) were adequately controlled with anti-arrhythmic agents. Amiodarone was administered to 38 pts; it was effective to prevent the episodes or to reduce their recurrence rate in 5 pts (13%), while it had to be discontinued due to side effects in 16 pts (42%).
In 16 out of the 54 pts (29%) AF became chronic after a mean of 6.6 years. Left atrial enlargement and worsening in left ventricular function were seen in all pts with chronic AF at a mean of 6.4 years after the initiation of symptoms.
Pts with evolution to chronic AF were older at the beginning (mean 54 years; range 33-70) than those who persisted in sinus rhythm (mean 42.8, range 15-71) (p<0.02).
In conclusion, the long-term prognosis of lone AF is not benign, the arrhythmia is difficult to control with antiarrhythmic agents and it frequently evolves to chronic AF.

These Companies contributed to the Congress