(malignant vasovagal syndrome) recurrent loss of consciousness due to a drop in blood pressure mediated by vasodilatation, bradycardia, or a combination of the two. Attacks resemble a simple faint, but can be very disabling because they are much more frequent and severe. Treatment comprises increased fluid and salt intake together with training in postural manoeuvres that may prevent attacks. A variety of drug treatments is available, but these are commonly ineffective. Implantation of a permanent pacemaker may be required if profound bradycardia is a feature.
Subjects: Medicine and Health.