NEW YORK (Reuters Health) – Isolating three or more pulmonary veins in patients with paroxysmal or persistent atrial fibrillation (AF) results in resolution or improvement of AF in the majority of patients, University of Michigan researchers report in a rapid release from the March 5th issue of Circulation: Journal of the American Heart Association.
Dr. Hakan Oral and colleagues from Ann Arbor, describe the outcome of 70 consecutive patients, 58 with paroxysmal AF and 12 with persistent AF, who underwent pulmonary vein isolation with radiotherapy. Treatment targeted the left superior, left inferior, and right superior pulmonary veins in all patients. The right inferior vein was also targeted in 20 patients. Six patients required a second isolation procedure, the researchers note.
At 5-month follow-up, 70% of the patients with paroxysmal AF were free of recurrent AF and 83% either were symptom free or had significant improvement in their condition, Dr. Oral's team found.
"These patients did not need anti-arrhythmia drugs or anticoagulants," Dr. Oral told Reuters Health. An additional 13% had a greater than 90% improvement in their symptoms, without medication or with a medication that had been ineffective before the procedure, he added.
However, at 5 months, only about 22% of patients with persistent AF did not need drug therapy. Twenty-nine percent had a greater than 90% improvement, Dr. Oral said. "When AF becomes persistent, then structural and electrical changes occur in the heart, which makes the ablation procedure less effective. So it may be necessary to intervene before paroxysmal AF becomes persistent AF," Dr. Oral advised.
This procedure can be done in less than 4 hours. For most patients, it requires only 2 hours. The procedure also is very safe, with a low incidence of significant complications (1%), Dr. Oral noted.
"Eventually this treatment will become the standard care for patients with paroxysmal AF," Dr. Oral said. Although the current treatments for persistent AF are not as effective, they will become more effective with new techniques currently being developed, he added.