A Randomized Trial Oral Propranolol versus Metroprolol in Treatment of Neurally Medicated Cyncope.
BACKGROUND
Beta-blockers has been claimed to be useful in chronic prophylaxis of neurally mediated syncope with frequent recurrences. However, efficacy of cardioselective and non-cardioselective beta-blockers has never been compared in a randomized study.


METHODS
From October 2003 to December 2004, 62 patients (32 men, mean age 44.8 +/- 19.3 years) who had at least one episode of syncope per month during previous 6-months and had positive tilt test were enrolled in this study. The patients were randomly assigned to receive either propranolol (Group I, n = 31) or metoprolol (Group II, n = 31). After one month, efficacy of treatment was also tested by a repeat head-up tilt test (HUTT).


RESULTS
There were no statistically significant differences between the two groups with respect to the HUTT pattern (P=0.25) and requirement for sublingual NTG during test (P=0.20). After one month of treatment, oral beta-blockers prevented the occurrence of syncope during second HUTT in 11 patients (35.5%) in the Group I and 9 (29%) patients in the Group II (P=0.58) and delayed the occurrence of symptoms in 9 Group I patients (29%) and 8 Group II patients (16%) (P=0.77). During the 16-months follow-up, 53 patients (85.5%) remained free of syncope. No statistically significant difference was observed between the two groups with respect to recurrence of syncope (P=0.47). In both groups, the patients in whom treatment efficacy was proved by a negative tilt test had similar recurrence of syncope as those patients who had a positive tilt test (Both P>0.05).


CONCLUSIONS
Both cardioselective and noncardioselective oral beta-blockers were similarly effective in preventing recurrence of syncope in patients with neurally-mediated syncope. In both groups, HUTT performed one month after the treatment had no role in prediction of responders.
Haghjoo
Majid
M
Department of Pacemaker and Electrophysiology, Rajaie Cardiovascular Medical and Research Center, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
Ali
Mohammad
M
Fazelifar
Amir Farjam
AF
Alizadeh
Abolfath
A
Sadr-Ameli
Mohammad Ali
MA