Syncope causes transient focal neurological symptoms

The prevalence of focal neurology (FN) as a consequence of syncope is unknown. The aim of the study was to determine its prevalence, risk factors and short-term consequences.

A consecutive sample of syncope-unit attendees during a 9-month period had detailed diagnostic syncope evaluation as per European Cardiac Society guidelines coupled with assessment for FN present during syncope/pre-syncope by screening questionnaire, follow-up interview and neuroimaging (1.5T magnetic resonance imaging [MRI]). All participants were followed up for 24 months. Risk factors for FN were identified by comparing FN cases with syncope controls without FN (3:1 ratio).

Five-hundred and forty consecutively attended for investigation of syncope (n = 401) and pre-syncope (n = 139). Thirty-one (5.7%) had FN events during hypotensive symptoms, mean age 49 years (19-85). The majority of FN cases had vasovagal syncope (VVS); 22 (71%), whereas eight had OH (25.8%) and one (3.2%) had cardiac arrhythmia. Median duration of FN was 15 min (IQR: 34.5). MRI in 28 (90%) was normal and in 3, old cerebral infarction was evident. Risk factors for FN/syncope were frequent syncope (P = 0·008), childhood syncope (P < 0.0005) and delayed diastolic recovery during active stand (P = 0·02). During 24-month follow-up and targeted intervention, no patients developed recurrence of FN.

One in 20 patients with syncope/pre-syncope have co-extant FN, which during 24-month follow-up, does not progress to a persistent deficit (>24 h). Awareness of co-occurrence of FN and syncope is important as stroke misdiagnosis results in aggressive anti-hypertensive management and future events may ensue.