BACKGROUND The dynamic autonomic processes leading to vasovagal syncope are poorly understood. METHODS AND RESULTS We used complex demodulation to continuously assess changes in respiration, R-R interval, and arterial pressure (blood pressure) variability during 60 degree head-up tilt in 25 healthy subjects with tilt-induced vasovagal syncope and 25 age-matched nonsyncopal control subjects. C...

Blood-injury phobia may present as a vasovagal syncope in response to the sight of blood or after receiving venipuncture. A 26-year-old man presented with a history of syncope induced by venipuncture. A transcranial Doppler (TCD) scan with monitoring of both heart rate and blood pressure reproduced the syncope and showed it to be vasovagal in nature. Treatment by practicing physical maneuvers, ...

V aspects of normal and abnormal circulatory adjustments in health and disease have been studied by many investigators. However, there has been little definitive physiologic evaluation of a commonly occurring disturbance in cardiovascular regulatory mechanisms in man, i.e., the common faint or "vasovagal syncope." This is due to difficulties in obtaining measurements of blood flow during rapid ...

Syncope is a common problem that many clinicians may encounter in various outpatient settings. Neurally mediated syncopal syndrome includes carotid sinus syndrome, situational syncope, and neurocardiogenic syncope (also known as vasovagal syncope), which is the most common cause of syncope in both children and adults, accounting for 50-66% of unexplained syncope. 2 The distinction between neuro...

M e t h o d s Design: Randomized controlled trial (Physical Counterpressure Manoeuvres Trial). Allocation: Concealed.* Blinding: Blinded (patients).* Follow-up period: Mean 14 months. Setting: 15 medical centers worldwide. Patients: 223 patients who were 16 to 70 years of age with recurrent vasovagal syncope (≥ 3 syncope episodes in the past 2 y or ≥ 1 syncopal spell and 3 presyncopal episodes ...

In this issue of Circulation: Cardiovascular Genetics, Barsheshet et al shed novel and unexpected light on the genetics of syncope, defined as a transient loss of consciousness caused by cerebral hypoperfusion with spontaneous recovery. Syncope is very common, with a cumulative incidence of 37% by age 60 years.1,2 In “young” patients, by far the most common cause of syncope is vasovagal syncope...

In this issue of Circulation: Cardiovascular Genetics, Barsheshet et al shed novel and unexpected light on the genetics of syncope, defined as a transient loss of consciousness caused by cerebral hypoperfusion with spontaneous recovery. Syncope is very common, with a cumulative incidence of 37% by age 60 years.1,2 In “young” patients, by far the most common cause of syncope is vasovagal syncope...