Author: Jason Friedman, MD
Senior Editor: Drew Duerson, MD
Editor: Jeffrey Feden, MD, FAMSSM

Patient Presentation:
A 36-year-old male with a history of anxiety presented to the emergency department via ambulance after a near-syncopal episode while running in an 8K trail race. He was about 3.5 miles into the race when he experienced lightheadedness and his vision began to fade. He denied chest pain or palpitations. His legs gave out and he fell forward to the ground, scraping all four limbs. He did not strike his head or lose consciousness. The patient reported a history of a similar event two years prior during a trail race on a hot day, resulting in syncope at that time. Following that incident, he was admitted to an outside hospital and treated for dehydration, but he does not recall the workup that was performed, if any. He reported occasional episodes of lightheadedness following competitive races in high school and college, sometimes accompanied by nausea or vomiting.

History:
Past Medical History: anxiety, depression
Medications: bupropion
Past Surgical History: deviated septum
Family History: Father: Barrett's esophagus. Mother: Diabetes mellitus, hypothyroidism. No known family history of cardiac disease or sudden cardiac death.
Social history: denied tobacco. 1-2 alcoholic drinks per week. Smokes marijuana 1-2 times per week.
ROS: otherwise negative

Physical Exam:
Height 180 cm, Weight 68 kg, BMI 21.0, Temp 97.6 (tympanic), HR 95, RR 22, BP 114/72, SpO2 95% on room air
General: Well developed, well-nourished white male, in no acute distress.
Head: Normocephalic, atraumatic.
Neck: Supple, no jugular venous distention, no midline tenderness, no pain with active range of motion.
Eyes: Pupils equally round and reactive to light. Extraocular movements intact bilaterally.
Respiratory: Clear to auscultation with equal breath sounds bilaterally. Normal excursion.
CV: Regular rate and rhythm. No murmurs or rubs.
Abdomen: Soft, nontender, non-distended. Normal bowel sounds.
Extremities: No cyanosis or edema. No calf swelling or tenderness. No deformities.
Skin: Abrasions to all extremities
Neuro: Alert and oriented to person, place, and time. Strength 5/5 in all extremities. Sensation to light touch intact in all extremities. Face symmetric. Cranial nerves intact. No pronator drift.

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