Episodes of apparent transient loss of consciousness: disorders a cardiologist should not ignore

Abstract

Affections such as psychogenic (functional) pseudosyncope and cataplexy are characterized by transient attacks without impairment of consciousness, but with loss of postural control and unresponsiveness. Therefore, these disorders should be differentiated from syncope and should not be ignored by the cardiologist, who is usually a reference point for patients with syncope or suspected syncope. Clinical findings that suggest psychogenic pseudosyncope include frequent attacks always in the presence of audience, a fall to the ground that may develop slowly enough to allow the patient to stagger and break the fall before hitting the floor, prolonged attacks (>10 min), many psychosomatic symptoms as the clinical context. In most cases, the differential diagnosis should be made with neurally mediated syncope; to this end, tilt test appears to be very useful. Cataplexy is a relevant symptom of narcolepsy; the differential diagnosis between cataplexy and syncope should be made only when symptoms of narcolepsy are mild. Clinical findings that suggest cataplexy include an emotional trigger - above all if the emotion is positive -, an "unreal" fall similar to that observed in patients with psychogenic pseudosyncope, repeated attacks in a daytime, symptoms of narcolepsy as the clinical context. Since cataleptic attacks are triggered by emotion, in most cases the differential diagnosis should be made with vasovagal syncope; a positive emotion as a trigger suggests a cataleptic attack.