PO-02-099 RADIOFREQUENCY CATHETER ABLATION OF ATRIAL TACHYCARDIA AND ATRIAL FIBRILLATION IN PATIENTS WITH PULMONARY HYPERTENSION. A SUBANALYSIS OF A PROSPECTIVE RANDOMIZED TRIAL

Abstract

Atrial fibrillation (AF) and related atrial tachycardias (AT), including typical atrial flutter (AFL), are common arrhythmias in patients with pulmonary hypertension (PH). We have shown, in the multicenter randomized trial, that extensive radiofrequency catheter ablation of the arrhythmogenic substrate on top of selective ablation of clinical arrhythmia alone was not beneficial in terms of arrhythmia recurrence in patients with AF / AT and PH. Irrespective of the randomization scheme, we compared clinical outcomes in patients with AF versus those with organized ATs. Out of 74 patients (42 males; the median age of 70 [IQR 61; 75] years) with combined post- and pre-capillary or isolated pre-capillary PH enrolled at 3 national sites, two study subgroups were composed: the AF group and the AT group (including AFL). The primary endpoint was arrhythmia recurrence >30 s without antiarrhythmic drugs after the 3-month blanking period. Idiopathic pulmonary arterial hypertension was found in 41 (55%) patients, chronic thromboembolic PH in 22 (30%), and PH associated with lung disease or hypoxia in 11 (15%). The AF group included 38 patients, and AT group included 36 patients (23 with AFL). The median duration of the follow-up period was 13 (IQR: 12; 21) months. The primary endpoint occurred in 23 patients (61 %) with AF vs. 9 patients (25 %) with AT (hazard ratio: 0.3, 95% confidence interval: 0.14-0.66; p = 0.003), Figure. In contrast to AF and other organized ATs, typical AFL did not reoccur during the follow-up. Out of 4 patients with documented arrhythmia after cavotricuspid isthmus ablation, 2 had AF and 2 patients manifested atypical AFL. More details are in the Table. Patients with PH and organized ATs manifested less frequent reoccurrence of arrhythmia after catheter ablation than patients with AF. Despite new arrhythmia could manifest, catheter ablation seems to be the most effective in PH patients with typical AFL. ClinicalTrials.gov Identifier: NCT04053361. Funding: The study was supported by the Ministry of Health of the Czech Republic, Grant Nr. NV18-02-00027.