The Electrophysiological Effect of the β-receptor Blocker on the Heart with Early After depolarization in vivo

Yu G-S¹, Tian J¹, Zhang D-R², Zhong J-R¹ Qian Y-R¹, Chen Y¹

¹ Children’s Hospital of Chongqing, Chongqing, China,

² The Second people’s hospital of Deyang, Sichuan, China

Objectives: The goal of this study is to discuss how metoprolol causes electrophysiological effect on the heart with early after depolarization (EAD), in order to research the mechanism of treatment of arrhythmias with metoprolol.

Method: A Franz 6F catheter was introduced into the left ventricle to record monophasic action potentials (MAPs) using the contact electrode technique to observe the influence to MAP change with CsCl-induced EAD when metoprolol is administered.

Result: the metoprolol can reduce the amplitude of early after depolarization (EAD% add up to 26.25±1.84%),

and comparing with the control group (EAD% up to 33.8±4.36 %), and the statistic analysis has significant difference（P＜0.05＝.

Conclusion: After depolarization is one of the mechanisms of arrhythmia. The useof metoprolol can inhibit the early after depolarization, and this has provided a theoretical for the use of metoprololto treat some arrhythmias on the clinic.

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