Predictors of successful radiofrequency catheter ablation of sinoatrial tachycardia.

Predictors of successful elimination of sinoatrial tachycardia (SAT) using radiofrequency current (RFC) were investigated in this report. Within 1991-1996 fourteen patients with SAT were subjected to electrophysiological study and radiofrequency catheter ablation (RFCA). Ten patients had sinoatrial reentrant tachycardia (SART), and four patients had chronic non-paroxysmal sinoatrial tachycardia (CNPSAT). The RFC (15-30 W, duration 10-30 sec) were applied during tachycardia in case of CNPSAT, and during sinus rhythm (SR) in case of SART. In 3 patients with SART RFC were delivered during tachycardia due to failing of RFC application, delivered during SR. During successful RFC attempts were noted: 1). In case of SART-transient development (3-6 sec) of SART (if RFC was delivered during SR), and acceleration of tachycardia rate with following termination of tachycardia (if application of RFC was performed during tachycardia); 2). In case of CNPSAT-transient development (4-7 sec) of low right atrial (3 patients) or junctional (1 patient) rhythm with rapid conversion to SR. All 14 patients have been free of tachycardia and have normal sinus node function during follow-up of 8-60 months. We conclude that predictors of successful elimination of SAT are: 1). In case of SART-acceleration of tachycardia rate before termination during RFC application (delivered during tachycardia), and transient development of SART during RFC application (delivered during SR); 2). In case of CNPSAT-transient development of low right atrial or junction rhythm (during application of RFC) with rapid conversion to SR.