Does radiofrequency ablation of the low posteroseptal right atrium reduce ventricular rate in a patient with atrial fibrillation and rapid ventricular response?
Selective radiofrequency ablation of the low posteroseptal right atrium successfully controlled rapid ventricular response in a patient with atrial fibrillation, suggesting a potential alternative to complete AV node ablation and pacemaker implantation.
A case is presented of a 58-year-old woman with atrial fibrillation and uncontrolled ventricular responses up to 180 beats/min despite therapy with digoxin. Radiofrequency energy was applied to the low posteroseptal right atrium in an attempt to modify "slow fiber" conduction. This resulted in a decrease in ventricular rate from 125 to 50 beats/min. Follow-up Holter monitor demonstrated an average heart rate of 64 beats/min (range 43-112). On exercise tolerance test, the maximum heart rate was 126. Modification of the low posterosepta right atrium may prove to be an alternative to AV node or His bundle ablation and pacemaker implantation in patients with poorly controlled atrial fibrillation and rapid ventricular response. The mechanism by which this approach was effective may be ablation of slow conducting AV nodal fibers with a short refractory period.
Fleck et al. (Mon,) studied this question.