Case Presentation: A 23 year-old man with no prior medical history presented with witnessed syncope.  Patient was playing basketball when he suddenly collapsed, initially unresponsive, regaining consciousness after minutes.  No seizure activity was observed.  VS were BP 116/71, HR 55, RR 16, O2sat 100% RA.  ECG showed sinus bradycardia with right axis deviation.  Physical exam [...]