シベンゾリンの電気生理学的検討—特に心房細動閾値について

Electroohvsiologic Study of Cibenzoline in Patients with Paroxysmal Atrial Fibrillation with Special Reference to Atrial Fibrillation Threshold

　発作性心房細動を有する7例において，右心耳に留置したJ型電極カテーテルを用いて電気生理学的検討を行った．シベンゾリン（200mg）経口投与によりP波幅，QRS波幅，PR間隔は有意に延長した．このP波幅の延長は刺激頻度が増すにつれて増大した．洞周期，洞自動能回復時間，ウェンケバッハ周期，右心耳有効不応期，QT時間は不変であった．ただしSSSを合併する1例で洞結節機能回復時間の延長をみた．高頻度持続心房刺激（50Hz,1秒間）を行い心房細動を誘発させる電流量を細動閾値とした．心房細動は1〜7mA（平均4.0±2.2mA）にて誘発可能であった．シベンゾリン投与後は7例中5例で上昇し，1例で不変，1例で悪化したが，心房細動閾値は7.3±3.4mAへと増加し統計学的に有意であった．シベンゾリンの心房細動予防効果が示唆された．

Electrophysiologic effects of cibenzoline were studied in 7 patients (6 males and one female) aged from 40 to 69 years (mean±SD; 52±10) with paroxysmal atrial fibrillation which was documented by 12 leads ECG or by 24 hours Holter monitoring. No organic heart diseases were found except in one patient with dilated cardiomyopathy and sick sinus syndrome (SSS). Ciben-zoline (200mg) given orally increased P wave duration, PR interval and QRS duration significantly. The dura-tion of P wave was gradually increased as the pacing frequency was increased.