How to unblur the vasovagal evidence?

Excerpt

Vasovagal syncope (VVS) is the most frequent, yet poorly understood, cause of transient loss of consciousness (TLOC). It affects up to 40% of the general population [1]. VVS has generally benign long-term prognosis and efficient first-line treatments, especially in younger individuals with sporadic attacks preceded by typical prodromes [1]. Simple interventions like explanation of VVS mechanism, education, life-style measures including dietary interventions (e.g. increased fluid and salt intake) and counterpressure manoeuvres appear to be effective in the majority of cases [1]. Despite these facts, the distressing presentation and frequent failure to establish the correct diagnosis fuels the high rate of emergency department visits, in-flight emergencies, hospital admissions and loads of tests with low clinical utility [2, 3]. Moreover, there is ample evidence emphasising the impact of VVS on daily living mainly due to high rates of anxiety and physical injury [2]. Nevertheless, in view of its frequent occurrence, the minority in whom these measures fail is still substantial. The prevalence of those with five or more vasovagal episodes during their life amounts to 5% of the general population [4]. For those with recurrent VVS attacks, often associated with trauma, and negative social or occupational consequences, the evidence supporting management is still rather blurry as we still have no well-defined treatment pathways for those who do not respond to first-line VVS interventions. Most pharmacological interventions are supported by class II recommendations, with the best evidence for use of midodrine and fludrocortisone against recurrent VVS (Fig. 1) [1, 5]. For a highly selective group of well-documented cases aged 40 years and older with dominant cardioinhibitory VVS, there is evidence for dual-chamber cardiac pacing [1].

…