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PloS One 2019To summarize the best available evidence on the effectiveness of physical counterpressure manoeuvers (PCM) for vasovagal syncope management compared to a control... (Meta-Analysis)
Meta-Analysis
AIMS
To summarize the best available evidence on the effectiveness of physical counterpressure manoeuvers (PCM) for vasovagal syncope management compared to a control intervention. Control interventions included either a PCM, no intervention, or other interventions feasible in a lay setting.
METHODS
A systematic literature search (March 21st 2018) was performed in the Cochrane Central Register of Controlled Trials, MEDLINE, and Embase. PCM were subdivided into 1) PCM decreasing orthostatic load (PCMOL), 2) PCM shortening the hydrostatic column between heart and brain (PCMHC), 3) PCM using mechanical compression of the veins (PCMMC). The primary outcome was syncope, secondary outcomes included systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR), stroke volume (SV), cardiac output (CO), and total peripheral resistance (TPR). When possible, a random effects meta-analysis was performed. Odds ratios (OR) with 95% confidence intervals (CI) were calculated for dichotomous outcomes, and mean differences (MD) or standardized mean differences (SMD) were calculated for continuous outcomes. Heterogeneity was assessed by means of the I2 statistic. The total body of evidence was evaluated by means of the GRADE methodology.
RESULTS
Eleven trials involving 688 people with vasovagal syncope were included. Risk of bias was high in all included studies. The total body of evidence (GRADE) was considered to be low or very low. PCM were found to improve syncope as compared to control (OR: 0.52, 95% CI [0.33;0.81], p = 0.004). Similarly, before-and-after studies without a control group showed a significant reduction in syncope following PCM (OR: 0.01, 95%CI [0.00;0.01], p<0.001). No studies investigated PCMOL. PCMHC increased SBP, DBP, MAP, SV, and CO, and decreased HR. PCMMC increased SBP, DBP, and MAP.
CONCLUSION
PCM may reduce syncope and increase SBP, DBP, and MAP. The effects on other outcomes are less clear. Additional high-quality studies are needed.
Topics: Bias; Blood Pressure; Female; Humans; Male; Motor Activity; Non-Randomized Controlled Trials as Topic; Randomized Controlled Trials as Topic; Syncope, Vasovagal; Treatment Outcome
PubMed: 30818337
DOI: 10.1371/journal.pone.0212012 -
Journal of Arrhythmia Oct 2018Vasovagal syncope (VVS) is defined by transient loss of consciousness with spontaneous rapid recovery. Recently, a closed-loop stimulation pacing system (CLS) has shown...
BACKGROUND
Vasovagal syncope (VVS) is defined by transient loss of consciousness with spontaneous rapid recovery. Recently, a closed-loop stimulation pacing system (CLS) has shown superior effectiveness to conventional pacing in refractory VVS. However, systematic review and meta-analysis has not been performed. We assessed the impact of CLS implantation and reduction in recurrent VVS events by a systematic review and a meta-analysis.
METHODS
We comprehensively searched the databases of MEDLINE and EMBASE from inception to September 2017. Included studies were published prospective or retrospective cohort, randomized controlled trial, and case-control studies that compared VVS events between recurrent, severe, or refractory cardioinhibitory VVS patient implanted with CLS and conventional pacing. Data from each study were combined using the random-effects, generic inverse variance method of DerSimonian and Laird to calculate odds ratios and 95% confidence intervals.
RESULTS
Six studies from November 2004 to October 2017 were included in this meta-analysis involving 224 recurrent, severe, or refractory cardioinhibitory VVS patients implanted with CLS and 163 recurrent, severe, or refractory VVS patients implanted with conventional pacing. CLS significantly reduced recurrent VVS events compared to conventional pacing (pooled odds ratio = 0.23, 95% confidence interval: 0.13-0.39, = 0.000, = 36.5%) as well as subgroup of four randomized controlled trial studies (pooled odds ratio = 0.28, 95% confidence interval: 0.17-0.44, = 0.000, = 39.2%).
CONCLUSION
Closed-loop stimulation significantly reduced recurrent VVS events up to 80% when compared to conventional pacing. Our study suggests that CLS is an effective tool for preventing syncope recurrences in patients with recurrent, severe, or refractory cardioinhibitory VVS.
PubMed: 30327702
DOI: 10.1002/joa3.12102 -
JACC. Clinical Electrophysiology Apr 2017The aims of this study were to quantify the degree of improvement in vasovagal syncope after assessment and to identify predictive factors. (Meta-Analysis)
Meta-Analysis
OBJECTIVES
The aims of this study were to quantify the degree of improvement in vasovagal syncope after assessment and to identify predictive factors.
BACKGROUND
No treatments for vasovagal syncope have been proved effective, but patients in all prospective studies appear to show a reduction in the likelihood of fainting.
METHODS
A systematic review and meta-analysis was performed of studies published from 1993 through 2013. Inclusion criteria were: 1) vasovagal syncope frequency in the preceding 1 to 2 years; and 2) the proportion of subjects with syncope in at least the first follow-up year. Random-effects methods were used.
RESULTS
Of 338 screened studies, 17 were analyzed, with a mean of 112 subjects (range 9 to 511 subjects). In the preceding epoch, 97% of subjects fainted, with 2.6 ± 1.0 syncopal spells per year. In the follow-up year, the proportion of patients with ≥1 syncope recurrence was 677 of 1,912 (35.4%), and in the meta-analysis, the proportion of subjects fainting was only 0.44 (95% confidence interval: 0.41 to 0.46; p < 0.001). Subjects in larger studies were less likely to faint than those in randomized trials (relative risk: 0.35 vs. 0.55; p = 0.004). The probabilities of ≥1 syncope recurrence in the observational versus randomized studies were 0.30 (95% confidence interval: 0.24 to 0.37) and 0.54 (95% confidence interval: 0.46 to 0.62), respectively (p < 0.001). None of the degree of blinding, type of intervention, age, sex, and number of recent faints predicted the probability of syncope recurrence. Heterogeneity was very high in all analyses (I = 60% to 96%).
CONCLUSIONS
The spontaneous remission rate in highly symptomatic syncope patients is high, and remission occurs in all types of studies. Improvement was more likely in larger and observational studies.
Topics: Adult; Aged; Female; Humans; Male; Middle Aged; Observational Studies as Topic; Randomized Controlled Trials as Topic; Remission, Spontaneous; Syncope, Vasovagal
PubMed: 29759452
DOI: 10.1016/j.jacep.2016.10.012 -
Journal of the American College of... Aug 2017To determine, using systematic review of the biomedical literature, whether pacing reduces risk of recurrent syncope and relevant clinical outcomes among adult patients... (Review)
Review
Pacing as a Treatment for Reflex-Mediated (Vasovagal, Situational, or Carotid Sinus Hypersensitivity) Syncope: A Systematic Review for the 2017 ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope: A Report of the American College of Cardiology/American Heart Association...
OBJECTIVES
To determine, using systematic review of the biomedical literature, whether pacing reduces risk of recurrent syncope and relevant clinical outcomes among adult patients with reflex-mediated syncope.
METHODS
MEDLINE (through PubMed), EMBASE, and the Cochrane Central Register of Controlled Trials (through October 7, 2015) were searched for randomized trials and observational studies examining pacing and syncope, and the bibliographies of known systematic reviews were also examined. Studies were rejected for poor-quality study methods and for the lack of the population, intervention, comparator, or outcome(s) of interest.
RESULTS
Of 3,188 citations reviewed, 10 studies met the inclusion criteria for systematic review, including a total of 676 patients. These included 9 randomized trials and 1 observational study. Of the 10 studies, 4 addressed patients with carotid sinus hypersensitivity, and the remaining 6 addressed vasovagal syncope. Among the 6 open-label (unblinded) studies, we found that pacing was associated with a 70% reduction in recurrent syncope (relative risk [RR]: 0.30; 95% confidence interval [CI]: 0.15-0.60). When the 2 analyzable studies with double-blinded methodology were considered separately, there was no clear benefit (RR: 0.73; 95% CI: 0.25-2.1), but confidence intervals were wide. The strongest evidence was from the randomized, double-blinded ISSUE-3 (Third International Study on Syncope of Uncertain Etiology) trial, which demonstrated a benefit of pacing among patients with recurrent syncope and asystole documented by implantable loop recorder.
CONCLUSIONS
There are limited data with substantive evidence of outcome ascertainment bias, and only 2 studies with a double-blinded study design have been conducted. The evidence does not support the use of pacing for reflex-mediated syncope beyond patients with recurrent vasovagal syncope and asystole documented by implantable loop recorder.
Topics: Advisory Committees; American Heart Association; Biomedical Research; Cardiac Pacing, Artificial; Cardiology; Disease Management; Humans; Practice Guidelines as Topic; Societies, Medical; Syncope; United States
PubMed: 28286220
DOI: 10.1016/j.jacc.2017.03.004