A single-center randomized controlled trial observing the safety and efficacy of modified step-up graded Valsalva manoeuver in patients with vasovagal syncope.

Li He,Yijun Yu,Lan Wang,Huanhuan Li,Ye Gu,Xiaoyun Zeng,Xiaoyan Liu,Lun Li,Moshe Swissa

doi:10.1371/journal.pone.0191880

Abstract

Non-pharmacological therapies, especially the physical maneuvers, are viewed as important and promising strategies for reducing syncope recurrences in vasovagal syncope (VVS) patients. We observed the efficacy of a modified Valsalva maneuver (MVM) in VVS patients. 72 VVS patients with syncope history and positive head-up tilt table testing (HUTT) results were randomly divided into conventional treatment group (NVM group, n = 36) and conventional treatment plus standard MVM for 30 days group (MVM group, n = 36). Incidence of recurrent syncope after 12 months (6.5% vs. 41.2%, P<0.01) and rate of positive HUTT after 30 days (9.7% vs.79.4%, P<0.01) were significantly lower in MVM group than in NVM group. HRV results showed that low frequency (LF), LF/ high frequency (HF), standard deviation of NN intervals (SDNN) and standard deviation of all 5-min average NN intervals (SDANN) values were significantly lower in the NVM and MVM groups than in the control group at baseline. After 30 days treatment, LF, LF/HF, SDNN, SDANN values were significantly higher compared to baseline in MVM group. Results of Cox proportional hazard model showed that higher SDNN and SDANN values at 30 days after intervention were protective factors, while positive HUTT at 30 days after intervention was risk factor for recurrent syncope. Our results indicate that 30 days MVM intervention could effectively reduce the incidence of recurrent syncope up to 12 months in VVS patients, possibly through improving sympathetic function of VVS patients.

Highlights

Vasovagal syncope (VVS) is a clinical syndrome resulting from systemic hypotension due to transient global cerebral hypoperfusion, and characterized by rapid onset, short duration and spontaneous complete recovery [1]
Results of Cox proportional hazard model showed that higher standard deviation of NN intervals (SDNN) and SDANN values at 30 days after intervention were protective factors, while positive head-up tilt table testing (HUTT) at 30 days after intervention was risk factor for recurrent syncope
Results of Cox proportional hazard model showed that higher SDNN and SDANN values, but not low frequency (LF)/high frequency (HF) ratio at 30 days after intervention, before and after adjusting for gender, age and beta-blockers, were protective factors for syncope recurrence (SDNN: HR = 0.974, 95%CI 0.951–0.997, P = 0.029; SDANN: HR = 0.966, 95%CI 0.939–0.993, P = 0.014; SDNN: adjusted HR = 0.966, 95%CI 0.937–0.996, P = 0.025; SDANN: adjusted HR = 0.950, 95%CI 0.915–0.986, P = 0.007, Table 2)

Summary

Introduction

Vasovagal syncope (VVS) is a clinical syndrome resulting from systemic hypotension due to transient global cerebral hypoperfusion, and characterized by rapid onset, short duration and spontaneous complete recovery [1]. Nowadays, following strategies were attempted to reduce syncope recurrences in VVS patients with variable efficacies: 1) physical techniques to improve orthostatic tolerance; 2) pharmacologic interventions to prevent depletion of intravascular volume and/or enhance arterial and venous tone; 3) cardiac pacing to avert bradycardia [4,8]; and 4) anatomically guided endocardial catheter ablation of ganglionated plexi in left atrium [9]. Among above mentioned therapy options, non-pharmacological therapies, especially the physical maneuvers, are viewed as important and promising strategies for reducing the syncope recurrences [5]. Brignole et al reported a comparable effect of isometric arm counterpressure maneuvers to abort impending VVS [11]. Van Dijk et al showed that physical counterpressure maneuvers were effective in preventing vasovagal syncope [12]

Methods

Results

Conclusion