Epileptic Seizures Versus Syncope: Pathophysiology and Clinical Approach

Abstract

Generalised epileptic seizures and syncope are two syndromes with similar clinical manifestation and their differentiation can be quite challenging. The aim of this review is to use an evidence-based approach in differentiating these two syndromes through the comprehension of the pathophysiological mechanisms involved and their clinical signs. Both syndromes affect regions of the forebrain and consciousness level, although, different mechanisms are involved. Syncope is a paroxysmal event secondary to a short-term decrease in cerebral perfusion, oxygenation or essential nutrients delivery. Generalised epileptic seizure activity is defined as the clinical manifestation of transient paroxysmal disturbances in brain function secondary to an imbalance between excitatory and inhibitory neurotransmitters. Clinical criteria, including precipitating events, clinical signs preceding, during and following the episodes and event duration, can be used to differentiate the two syndromes. Although these criteria might be useful for the practitioner, definite conclusions should be precluded due to the lack of original research articles and weak evidence on this specific field. Application:The review might be a useful tool for the general practitioner and clinical scientist as it will aid towards the differentiation of two syndromes, i.e. generalised epileptic seizures and syncope, with similar clinical presentation.

Children with transient loss of consciousness: Clinical characteristics and the effectiveness of diagnostic tests

“…Therefore, although clinical symptoms and signs can help the physician to make a rapid diagnosis, it is difficult to distinguish between the two conditions based only on clinical manifestations. 15 In a study of children with unexplained syncope by Alehan et al, 25 the sensitivity and specificity of the HUTT with pharmacological simulation were 76.6% and 86.7%, respectively. Many studies have demonstrated the diagnostic effectiveness of the HUTT in children and adolescents in vasovagal syncope.…”

“Resistance Is Futile”: A Pilot Study into Pseudoresistance in Canine Epilepsy

“…Cardiac channelopathies often manifest with convulsive syncope, leading to a misdiagnosis of epilepsy which puts these patients at risk of developing serious and life-threatening arrhythmias [40]. Differentiation of generalised epileptic seizures and syncope can also be quite challenging in veterinary medicine, since the two syndromes can share a similar clinical manifestation [41,42]. None of the dogs in this study had an arrythmia misdiagnosed as MRE as a cause for pseudoresistance.…”

Therapie epileptischer Anfälle bei Hund und Katze

“…Ein kritisches Überdenken der Differenzialdiagnosen ist an dieser Stelle essenziell. Insbesondere Synkopen sind je nach Ausprägung u. U. schwierig von epileptischen Anfällen zu differenzieren 39 . Dasselbe kann auch auf episodisch auftretende Bewegungsstörungen – sogenannte paroxysmale Dyskinesien – zutreffen.…”