Psychogenic Pseudosyncope and Conversion Reactions: Neuroimaging and Management

Psychogenic pseudosyncope (PPS) should be considered in the differential diagnosis of syncope. It is defined as the appearance of transient loss of consciousness (TLOC) in the absence of true TLOC. Psychiatrically it is characterized as a somatic symptom disorder (formerly conversion disorder) and is clinically considered similar to psychogenic non-epileptic seizures (PNES). Recent functional neuroimaging studies suggest that these patients are not feigning their symptoms. Patients with PPS usually present to their cardiologist, neurologist or primary care physician, who may feel uncomfortable in presenting this diagnosis and managing the patient. The prevalence of PPS is estimated between 0-8% in patients presenting for syncope evaluations, which is likely an underestimate as the diagnosis is not actively investigated. Diagnostic clues include the young female demographic, prolonged apparent TLOC compared with the typical duration of less than one minute in syncope patients, increasing frequency of episodes, more pre-episode symptoms such as light-headedness and tingling, and eye closure during episodes. Patients with somatic symptom disorder are more likely to report a history of physical or sexual abuse and present with comorbid depression and anxiety disorders. PPS can be accurately diagnosed with a thorough history, and ancillary investigation with head-up tilt testing (HUTT), electroencephalogram (EEG) or trans-cranial Doppler (TCD) in selected cases. While patients can be reluctant to engage in psychiatric care, cognitive behavioral therapy (CBT) is the evidenced-based treatment of choice. This clinically focused session will cover the underpinnings, diagnosis and management of PPS.