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Background: Rotors are the source of atrial fibrillation (AF). However, the ablation of rotors for persistent AF is challenging. The purpose of this study was to identify the dominant rotor by accelerating the organization of AF using a sodium channel blocker and detecting the rotor's preferential area that governs AF. Methods: Overall, 30 consecutive patients with persistent AF who underwent pulmonary vein isolation and still sustained AF were enrolled. Pilsicainide 50 mg was administered. An online real‐time phase mapping system (ExTRa Mapping™) was used to identify the meandering rotors and multiple wavelets in 11 left atrial segments. The time ratio of non‐passive activation (%NP) was evaluated as the frequency of rotor activity in each segment. Results: Conduction velocity became slower—from 0.46 ± 0.14 to 0.35 ± 0.14 mm/ms (p =.004)—and the rotational period of the rotor was significantly prolonged—156 ± 21 to 193 ± 28 ms/cycle (p <.001). AF cycle length was prolonged from 169 ± 19 to 223 ± 29 ms (p <.001). A decrease in %NP was observed in seven segments. Additionally, 14 patients had at least one complete passive activation area. Of them, the use of high %NP area ablation resulted in atrial tachycardia and sinus rhythm in two patients each. Conclusions: A sodium channel blocker organized persistent AF. In selective patients with a wide organized area, high %NP area ablation could convert AF into atrial tachycardia or terminate AF. [ABSTRACT FROM AUTHOR]

Catalytic activity of a 1 wt% Au/TiO2 catalyst is markedly improved by loading a large amount of FeO x , on which the oxidation of CO in excess H2 is selectively promoted at temperature lower than 60 °C. Oxidation of CO with O2 on the FeO x /Au/TiO2 catalyst is markedly enhanced by H2, and H2O moisture also enhances the oxidation of CO but its effect is not so large as the promotion by H2. We deduced that activation of Au/TiO2 catalyst by loading FeO x is not caused by the size effect of Au particles but a new reaction path via hydroxyl carbonyl intermediate is responsible for the superior activity of the FeO x /Au/TiO2 catalyst. [ABSTRACT FROM AUTHOR]