Metoprolol was significantly more effective than clonidine in abolishing syncope during head-up tilt testing (95% vs 5%, P<0.001) in patients with malignant vasovagal syncope.
RCT (n=20)
Double-blind
Randomized crossover
Does metoprolol improve syncope prevention compared to clonidine in patients with malignant vasovagal syncope?
Metoprolol is significantly more effective than clonidine in preventing syncope during head-up tilt testing in patients with malignant vasovagal syncope.
Absolute Event Rate: 95% vs 5%
p-value: p=< 0.001
OBJECTIVE: To evaluate the efficacy of head up tilt guided treatment with metoprolol and clonidine in preventing the recurrence of syncope in patients with malignant vasovagal syncope. PATIENTS: 20 patients (9 men and 11 women, mean age 33 (SD 17), range 14 to 62 years) with severe symptoms. DESIGN: Randomised double blind crossover trial; efficacy was assessed by head up tilt testing. RESULTS: Metoprolol was more effective than clonidine in abolishing syncope (19/20 v 1/20, P < 0.001) but clonidine showed some beneficial effects on time to syncope and severity of hypotension in 12 patients. During an average follow up of 15 (3) months there was a significant reduction in the recurrence of symptoms compared with the previous year in patients who had tilt up guided treatment (18 metoprolol, 1 clonidine). CONCLUSIONS: Treatment guided by head up tilting is a reliable method of treating patients with malignant vasovagal syndrome. Metoprolol was an effective long term treatment for preventing syncope. High doses were more effective and a careful dose titration period helped to minimise withdrawal symptoms and side effects.
Biffi et al. (Sat,) conducted a rct in Malignant vasovagal syncope (n=20). Metoprolol vs. Clonidine was evaluated on Abolishing syncope assessed by head up tilt testing (p=< 0.001). Metoprolol was significantly more effective than clonidine in abolishing syncope during head-up tilt testing (95% vs 5%, P<0.001) in patients with malignant vasovagal syncope.