THE CASE
A 23-year-old woman with past medical history of bipolar II disorder and a REM-specific seizure disorder that resolved at age 9 presented after a syncopal episode. The patient reported an initial sensation of lightheadedness while at work, which was followed by a syncopal episode with brief (1-2 min) loss of consciousness and a minor head injury.
She denied other prodromal symptoms including chest pain, shortness of breath, palpitations, and nausea. She also did not experience convulsions, urinary/bowel incontinence, or confusion upon regaining consciousness.
She denied previous syncopal episodes. However, she reported that, 2 weeks prior, there had been an event similar to that of her presenting complaint. During that episode, she experienced lightheadedness and a fall without loss of consciousness.
The patient had been prescribed a regimen of sertraline 100 mg/d and aripiprazole 10 mg/d to maintain mood stability. She had self-discontinued these medications about 8 months prior to presentation. A recent return of her depressive features had prompted a restart of this regimen 1 week before her first fall, without an initial taper upward.
While in the emergency department, she became bradycardic (heart rate, 38 beats/min) and hypotensive (blood pressure, 70/40 mm Hg). She subsequently became increasingly somnolent and had 1 episode of emesis. An electrocardiogram (EKG) revealed sinus bradycardia without other acute abnormalities (FIGURE).
Blood work including a basic metabolic panel, complete blood count, and cardiac enzymes were all within normal limits. Computed tomography of the head revealed no intracranial pathology. Her vitals were initially unresponsive to a fluid bolus but improved and stabilized after administration of intravenous atropine 0.5 mg.
Aripiprazole was held and sertraline was decreased to 75 mg on hospital Day 1, with close monitoring of her mood. Cardiology was consulted and followed the patient during her stay. The patient was monitored on telemetry for 3 days, exhibiting only sinus bradycardia with a stable heart rate of 45-55 beats/min. Systolic blood pressures were stable within 120 to 130 mm Hg. Transthoracic echocardiogram performed on hospital Day 2 was unremarkable, revealing a normal left ventricular ejection fraction of 65% and no wall motion abnormalities. She had no recurrence of the syncope or emesis.
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