Prevention of Syncope Trial (POST): A Randomized, Placebo-Controlled Study of Metoprolol in the Prevention of Vasovagal Syncope (original) (raw)

Effect of Metoprolol on Quality of Life in the Prevention of Syncope Trial

Journal of Cardiovascular Electrophysiology, 2009

Beta-Blockers and Quality of Life in Syncope. Introduction: Vasovagal syncope is common, often recurrent, and reduces quality of life. No therapies have proven useful to improve quality of life in adequately designed randomized clinical trials. Beta-blockers have mixed evidence for effectiveness in preventing syncope. Methods: The Prevention of Syncope Trial was a randomized, placebo-controlled, double-blind, multinational, clinical trial that tested the hypothesis that metoprolol improves quality of life in adult patients with vasovagal syncope in a 1-year observation period. Randomization was stratified in strata of patients <42 and ≥42 years old. The quality of life questionnaires Short Form-36 (SF-36) and Euroqol EQ-5D were completed at baseline and after 6 and 12 months of treatment by 204, 132, and 121 patients, respectively. Results: There were 208 patients, mean age 42 ± 18, of whom 134 (64%) were females. All had positive tilt tests. There was no improvement in quality of life during the trial in the entire group or in either treatment arm. Patients in the metoprolol treatment arm did not have improved quality of life compared to the patients in the placebo arm using either the SF-36 or EQ5D after either 6 or 12 months. Finally, there was no improvement in quality of life associated with metoprolol use in patients either <42 or ≥42 years of age. Conclusion: Metoprolol does not improve quality of life in patients with recurrent vasovagal syncope and a positive tilt test.

Prevention of Syncope Trial (POST)

Circulation, 2006

Background— Previous studies that assessed the effects of β-blockers in preventing vasovagal syncope provided mixed results. Our goal was to determine whether treatment with metoprolol reduces the risk of syncope in patients with vasovagal syncope. Methods and Results— The multicenter Prevention of Syncope Trial (POST) was a randomized, placebo-controlled, double-blind, trial designed to assess the effects of metoprolol in vasovagal syncope over a 1-year treatment period. Two prespecified analyses included the relationships of age and initial tilt-test results to any benefit from metoprolol. All patients had >2 syncopal spells and a positive tilt test. Randomization was stratified according to ages <42 and ≥42 years. Patients received either metoprolol or matching placebo at highest-tolerated doses from 25 to 200 mg daily. The main outcome measure was the first recurrence of syncope. A total of 208 patients (mean age 42±18 years) with a median of 9 syncopal spells over a media...

Age-dependent effect of β-blockers in preventing vasovagal syncope

Circulation. Arrhythmia and electrophysiology, 2012

β-blockers have little effectiveness in preventing vasovagal syncope in unselected populations, but they might be effective in older patients. We determined whether β-blockers prevent vasovagal syncope in an age-related fashion. Two populations were studied. A proportional hazards analysis was performed on an observational cohort study of 153 patients with vasovagal syncope, 52 of whom received β-blockers. A multivariable proportional hazards model stratified by center was performed on 208 participants in the randomized Prevention of Syncope Trial (POST), examining the interaction between age group and treatment with metoprolol. Age-specific hazard ratios were estimated for both studies and combined using the inverse variance meta-analytic method. In the cohort study, the hazard ratio for syncope if treated with β-blockers was 1.54 (95% CI, 0.78-3.05) for patients aged <42 years and 0.48 (95% CI, 0.12-1.92) for patients aged ≥ 42 years. In POST, the proportional hazards model sho...

Medical Management of Vasovagal Syncope: A Network Meta Analysis

Introduction: Multiple pharmacologic therapies have been studied to prevent recurrence in patients with vasovagal syncope. Multiple head to head comparisons have been done with varying results. We aimed to perform a network meta-analysis to assess the efficacy of pharmacologic therapies in preventing recurrent syncope in patients with vasovagal syncope. Methods: A systematic review of the literature was performed to identify randomized controlled trials describing recurrence of vasovagal syncope after initiation of pharmacologic treatment in patients with syncope who had a baseline positive tilt table test. A Bayesian network meta-analysis was conducted utilizing the geMTC package available for R: A Language and Environment for Statistical Computing. Results: None of the included pharmacological therapies were found to significantly reduce the recurrence of vasovagal syncope when compared to placebo. When compared to one another atenolol did offer significant reduction in syncopal episodes when compared to cafedrine. Dihydroergotamine ranked the highest while cafedrine ranked the lowest. Conclusions: Pharmacologic therapies do not offer significant reduction in recurrence of vasovagal syncope. First line therapy for these patients should include lifestyle changes such as increased fluid intake, and when appropriate, increased salt intake.

Management and therapy of vasovagal syncope: A review

World Journal of Cardiology, 2010

Vasovagal syncope is a common cause of recurrent syncope. Clinically, these episodes may present as an isolated event with an identifiable trigger, or manifest as a cluster of recurrent episodes warranting intensive evaluation. The mechanism of vasovagal syncope is incompletely understood. Diagnostic tools such as implantable loop recorders may facilitate the identification of patients with arrhythmia mimicking benign vasovagal syncope. This review focuses on the management of vasovagal syncope and discusses the non-pharmacological and pharmacological treatment options, especially the use of midodrine and selective serotonin reuptake inhibitors. The role of cardiac pacing may be meaningful for a subgroup of patients who manifest severe bradycardia or asystole but this still remains controversial.

Effect of Etilefrine in Preventing Syncopal Recurrence in Patients With Vasovagal Syncope

Circulation, 1999

Background —Etilefrine is an α-agonist agent with a potent vasoconstrictor effect, which is potentially useful in preventing vasovagal syncope by reducing venous pooling and/or by counteracting reflex arteriolar vasodilatation. The present multicenter, randomized, placebo-controlled study was designed to evaluate the efficacy of this drug for the long-term management of patients with recurrent vasovagal syncope. Methods and Results —In the 20 participating centers, 126 patients with recurrent vasovagal syncope (at least 3 episodes in the last 2 years) and a positive baseline head-up tilt response were randomly assigned to placebo (63 patients) or etilefrine at a dosage of 75 mg/d (63 patients) and were followed up for 1 year or until syncope recurred. The primary end-point of the study was the first recurrence of syncope. There were no differences between the 2 study groups in the patients’ baseline characteristics. During follow-up, the group treated with etilefrine had a similar i...