Beyond Seizures: the enigma of cardioinhibitory malignant vasovagal syncope in a complicated pregnancy journey

A pregnant woman in her late 20s with a history of epilepsy since childhood presented with recurrent loss of consciousness and witnessed twitching and involuntary muscle contractions. She had hyperemesis during pregnancy reporting four previous miscarriages attributed to seizures. During evaluation in cardiac telemetry and while suffering from severe nausea, the patient experienced prolonged ventricular asystole resulting in convulsive syncope and was diagnosed with cardioinhibitory malignant vasovagal syncope (CMVS). Initiation of levetiracetam was recommended for 6 months, and after undergoing dual-chamber pacemaker placement, her neurological symptoms resolved despite persistent hyperemesis during the first trimester, leading to a successful vaginal delivery. 4 years later, the patient remains asymptomatic. This case emphasises the importance of conducting a thorough differential diagnosis in patients with atypical seizure presentations, the multidisciplinary approach required to assure optimal outcomes in cardio-obstetric cases and the role of selective pacemaker placement in patients with documented prolonged ventricular asystole associated with CMVS.