ABSTRACT
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.
ABSTRACT
BACKGROUND: The diagnostic yield of Holter monitoring in patients with syncope is variably reported to be between 6%-20%. This study was done to define predictors of arrhythmic events during the second day of Holter monitoring in patients whose first day Holter recording was normal. METHODS AND RESULTS: Two serial 24-hour Holter recordings were obtained in a consecutive series of 100 patients (49 patients with unexplained syncope and/or pre-syncope and 51 patients with palpitation). The age of patients was 53.4 +/- 16.9 years and 51 were men. Seventy-six patients had underlying heart disease. Main electrocardiographic findings were found in 40 (40%) patients including non-sustained ventricular tachycardia in 19, sinus pause in 13, symptomatic bradycardia in 5, paroxysmal atrial fibrillation in 4, sustained supraventricular tachycardia in 2, and Mobitz type II second-degree atrioventricular block in 3 patients. Twenty-seven (27%) patients had 33 main electrocardiographic findings during the first day and 13 out of the remaining 73 patients (17.8%) had it during the second day of Holter recording. Presenting symptom (syncope/pre-syncope), age > 65 years, and male gender were significantly associated with increased likelihood of main electrocardiographic findings during the second day of Holter monitoring (p = 006, 0.023, and 0.024, respectively). The risk of main electrocardiographic findings ranged from 5% in patients with one or no predictor to 35% in those with > or = 2 predictors (OR = 9.95, 95% CI = 2.01-49.2, p = 0.002). CONCLUSIONS: Presenting symptom (syncope/pre-syncope), age > 65 years, and male gender increased the likelihood of main electrocardiographic findings during the second day of Holter monitoring.