Effect of pilsicainide, a pure sodium channel blocker, on spiral waves during atrial fibrillation: theoretical analysis by numerical simulation.
This study investigated the effects of a particular type of sodium channel blocker, pilsicainide, on spiral waves, which are a possible mechanism of atrial fibrillation, by using numerical simulation. A meandering spiral wave was induced on a two-dimensional matrix corresponding to the isolated atrial myocardium. The model attempted to simulate the changes caused by pilsicainide. The conductivity was depressed and the refractory period was prolonged with little change in the action potential duration. The dynamic change in the refractory period depended on the preceding coupling interval. A blockline occurred and changed gradually because of the change in the refractory period. The spiral wave became a stable reentry rotating around the blockline, decreasing the excitation frequency in the matrix before rushing out of the matrix. The electrocardiogram showed a slow coarse wave, as well as a real electrocardiographic change by pilsicainide. This might, in part, explain how pilsicainide acts on atrial fibrillation. Key words: sodium channel blocker, pilsicainide, spiral wave, atrial fibrillation, computer simulation.
Namba
T
T
Department of Cardiovascular Medicine, Okayama University Medical School, Okayama City, Japan.
Ashihara
T
T
Nakazawa
K
K
Ohe
T
T
D000889:Anti-Arrhythmia Agents / Q000494:pharmacology*; D001281:Atrial Fibrillation / Q000503:physiopathology*; D003198:Computer Simulation; D046508:Culture Techniques; D004562:Electrocardiography / Q000187:drug effects*; D006325:Heart Atria / Q000187:drug effects / Q000503:physiopathology; D006801:Humans; D008012:Lidocaine / Q000031:analogs & derivatives* / Q000494:pharmacology; D012815:Signal Processing, Computer-Assisted; D026941:Sodium Channel Blockers; D015222:Sodium Channels / Q000502:physiology
D000889:Anti-Arrhythmia Agents; D026941:Sodium Channel Blockers; D015222:Sodium Channels; D008012:Lidocaine; C042288:pilsicainide