Case: Two episodes of syncope point to an underlying condition

Wanting to get more history, you step into the room, and find a pair of anxious parents and a pleasant young man lying in bed. He appears a bit tired but states that he "feels fine now, just a little dizzy when [I] stand, but okay to go home." He and his mother recall the first syncopal event last night around midnight, when he was rising from bed, felt dizzy, slumped over, and hit his chin on the side of his bed. His mother heard him fall, and rushed into his room to find him waking up. She helped him back into bed, and seeing he was feeling much better, left him to sleep through the night.

In the morning after waking him, his mother noticed him become unsteady as he stood, and he again fainted. She caught him this time. She did not see any seizure-like activity, and he himself described no preceding palpitations or symptoms other than feeling like he was "sweaty and blacking out." He soon regained consciousness, and was alert and at baseline again. It was at this point that they called the paramedics, and were brought to the ED.

Further history shows that he is indeed a healthy young man, with no significant past medical or family history including cardiac, and is on no medications or homeopathic medicines or herbs (he is of first-generation Chinese descent, and the city you practice in uses quite a bit of complementary medicine). He has been afebrile, without any pain, diarrhea, constipation, nausea, or vomiting, and has had no recent travel. His last bowel movement was a day ago, and was soft and brown, and his last meal was dinner last night. He's had no constitutional symptoms including weight loss, loss of appetite, night sweats, or fatigue. The remainder of his review of systems is negative, which includes a confidential drug history with his parents out of the room. No one in his family has had similar symptoms.

Your exam is significant for a 2/6 systolic ejection murmur at the upper left sternal border, and you think he might appear slightly pale but it's hard to tell with the ED's lighting. He has a completely benign abdominal exam, capillary refill time of approximately two seconds, and not much else. He is neurologically intact and at his baseline per his mother.