神経調節性失神に対するメトプロロールとジソピラミドの効果の検討

Efficacy of Metoprolol and Disopyramide on Neurally Mediated Syncope

　神経調節性失神の第1選択薬は，β遮断薬とジソピラミドというのが一般的である．しかし，両者を同一患者で比較した研究はない．そこでヘッドアップチルト試験で誘発される神経調節性失神患者に順次，ジソピラミドとメトプロロールを投与し有効性を検討した．対象は，原因不明の失神を主訴とし，器質的心疾患がなく，ヘッドアップチルト試験が陽性だった8例で，引き続き，ジソピラミド，300mgまたは600mgおよびメトプロロール120mg各々1週間投与しヘッドアップチルト試験を繰り返した．ジソピラミド投与例では4例で，メトプロロール投与例では7例で失神が消失した．神経調節性失神にはジソピラミドもメトプロロールも有効であったが，本研究ではメトプロロールのほうがより有効である印象を受けた．

First line drugs for neurally mediated syncope were generally accepted as beta adrenergic blockade and disopyramide. However, there is no study to compare the efficacy of those two drugs against the same patients. We successively administered them against tilt induced syncope-patients.

Eight subjects who were complaint of syncope of unknown origin without structural heart disease show-ed positive haed-up tilt testing. They were reexamined head-up tilt test taking 300mg or 600mg of disopyr-amide and 120mg of metoprolol for a week by turn. Numbers of subjects whose syncope was abolished were 4 in disopyramide group and 7 in metoprolol group.

Both disopyramide and metoprolol are effective against neurally mediated syncope.

In this study, we got the impression that metoprolol was more effective than disopyramide.