Variable electrocardiographic effects of short-term quinidine sulfate administration in Brugada syndrome.

Abstract

Quinidine, a class I antiarrhythmic agent with blocking property of transient outward current, is a possible candidate for the suppression of ventricular fibrillation in patients with Brugada syndrome; although there is a concern that its ability to these effects may be proarrhythmic. Therefore, we evaluated the effect of quinidine sulfate on ST-segment elevation in Brugada syndrome. In 8 patients with Brugada syndrome, the magnitude of ST-elevation at the J-point (ST(J)), and the ST-segment configuration in leads V1-V3, were compared before and on day 2 after the initiation of quinidine administration. In 3 patients, quinidine attenuated ST(J) by > or = 0.1 mV. Of these 3 patients, ST-segment elevation was normalized in 2 patients, while the ST-segment configuration was unchanged in another. In another 3 patients, quinidine augmented ST(J) by > or = 0.1 mV without any change of ST-segment configuration, and the augmentation was returned to baseline after the discontinuation of quinidine. Quinidine exhibited no effect on the ST-segment in the remaining 2 patients. The favorable effects of quinidine on the ST-segment tended to be more pronounced in patients with prominent ST-elevation at baseline. In 1 patient, quinidine was effective in eliminating both ST-segment elevation and repetitive tachyarrhythmia episodes. In conclusion, the effects of quinidine on ST-segment elevation were variable. Quinidine may potentially augment the ST-segment elevation in some patients with Brugada syndrome.

• Authors: Hiroshi Watanabe, Masaomi Chinushi, Takashi Washizuka, Hirotaka Sugiura, Takashi Hirono, Satoru Komura, Yukio Hosaka, Masayuki Yamaura, Yasutaka Tanabe, Hiroshi Furushima, Satoru Fujita, Yoshifusa Aizawa
• Journal: Pacing and clinical electrophysiology : PACE (Pacing Clin Electrophysiol) Vol. 28 Issue 5 Pg. 372-7 (May 2005) ISSN: 0147-8389 [Print] United States
• PMID: 15869667 (Publication Type: Journal Article)

Chemical References

• Anti-Arrhythmia Agents
• Quinidine

Topics

• Adult
• Aged
• Anti-Arrhythmia Agents (administration & dosage)
• Bundle-Branch Block (physiopathology)
• Electrocardiography (drug effects)
• Female
• Humans
• Infant
• Male
• Middle Aged
• Quinidine (administration & dosage)
• Syncope
• Syndrome
• Ventricular Fibrillation (drug therapy)