The efficacy of non-pharmacological and non-pacing therapies in preventing vasovagal syncope: Tilt training, physical counter pressure maneuvers, and yoga - A systematic review and meta-analysis

Background: Vasovagal syncope (VVS) is a prevalent condition characterized by a sudden drop in blood pressure and heart rate, leading to a brief loss of consciousness and postural control. Recurrent episodes of VVS significantly impact the quality of life and are a common reason for emergency department visits. Non-pharmacological interventions, such as tilt training, physical counter pressure maneuvers, and yoga, have been proposed as potential treatments for VVS. However, their efficacy in preventing VVS remains uncertain. Methods: A systematic review and meta-analysis were conducted following PRISMA guidelines. PubMed, Web of Science, and Embase were searched up to March 2023 for randomized controlled trials comparing nonpharmacological interventions with control in preventing VVS recurrence. The primary outcome was the recurrence rate of VVS episodes. Results: A total of 1130 participants from 18 studies were included in the meta-analysis. The overall mean effect size for non-pharmacological interventions versus control was 0.245 (95 % CI: 0.128-0.471, p -value <0.001). Subgroup analysis showed that yoga had the largest effect size (odds ratio 0.068, 95 % CI: 0.018-0.250), while tilt training had the lowest effect size (odds ratio 0.402, 95 % CI: 0.171-0.946) compared to control. Physical counter pressure maneuvers demonstrated an odds ratio of 0.294 (95 % CI: 0.165-0.524) compared to control. Conclusion: Non-pharmacological interventions show promise in preventing recurrent VVS episodes. Yoga, physical counter pressure maneuvers, and tilt training can be considered as viable treatment options. Further research, including randomized studies comparing pharmacological and non-pharmacological approaches, is needed to evaluate the safety and efficacy of these interventions for VVS treatment.