Aims: Though right atrial appendage tachycardia (RAAT) has been described, no studies to date have focused on its clinical characterization. The aim of the present study was to analyze its clinical, electrocardiographic (ECG), and electrophysiologic (EP) characteristics and the results of radiofrequency ablation (RFA) in RAAT.
Methods and results: Out of 186 consecutive patients undergoing RFA for AT, 15 (8%) had focal RAAT. Mapping was performed using conventional catheters or a 3D electroanatomic mapping system. Patients with RAAT were more likely to be male (66 vs. 38%; P= 0.013) and younger (32 +/- 12.6 vs. 55 +/- 13.2 years; P < 0.001) than patients with AT originating elsewhere. They were also more likely to have dyspnea (27 vs. 7.6%; P = 0.03), incessant tachycardia (53 vs. 16%; P < 0.001), and left ventricular systolic dysfunction (27 vs. 5%; P = 0.018). RFA was effective in all patients (100 vs. 75%; P = 0.022) and no recurrences (0 vs. 8%; P = 0.31) were observed during a mean follow-up of 37 +/- 36 months. A specific ECG pattern was identified, consisting of negative P-waves in leads V1-V2 and a transition to positivity in the rest of the precordial leads. This ECG pattern correctly identified RAAT with a sensitivity of 100%, a specificity of 98%, a positive predictive value of 88%, and a negative predictive value of 100%.
Conclusion: Right atrial appendage tachycardia is more prevalent in young male patients and is commonly associated with tachycardiomyopathy. RFA is effective over long-term follow-up. A characteristic ECG pattern identifies RAAT with a very high sensitivity and specificity.