Snapshot A 65-year-old man presents to the emergency department after his wife saw him collapse onto the ground. He stood up from bed to make his way to the restroom. When he stood up, his wife saw him briefly stop walking, turn pale, and fall to the ground. After 10 seconds, he regained consciousness and said he felt lightheaded and his vision became blurry prior to passing out. Medical history is significant for hypertension and newly diagnosed benign prostatic hyperplasia. He is taking hydrochlorothiazide and terazosin. Physical examination is unremarkable. A 12-lead electrocardiogram does not demonstrate any cardiac arrhythmias or structural changes. Introduction Definition transient loss of consciousness secondary to poor cerebral nutrient flow syncope has the following features rapid onset the loss of consciousness is of short duration recovery is complete and spontaneous there are 3 types of syncope reflex, orthostatic, and cardiac Etiology Reflex syncope (neurally-mediated reflex syncope) vasovagal syncope triggers include emotional stress/fear blood phobia pain carotid sinus syncope syncope with minor stimulation of the carotid sinus (shaving, putting on neckties, or applying minor pressure) situational syncope triggers include coughing/sneezing defecation post-prandial Orthostatic syncope autonomic dysfunction causes include multiple system atrophy Cardiac syncope arrhythmia structural heart disease Neurogenic syncope stroke/vascular insufficiency (vertebrobasilar artery) Presentation Symptoms presyncope lightheadedness palpitations visual changes (e.g., blurring and whiting-out) Physical exam orthostatic blood pressures should be obtained cardiac auscultations to determine the presence of a pathologic murmur Studies Electrocardiogram indication used to rule out a cardiac cause of syncope ventricular tachycardia atrial fibrillation supraventricular tachycardia torsades de pointes look for QT prolongation left ventricular hypertrophy look for large voltages in leads that serve the left ventricle arrhythmogenic right ventricular dysplasia epsilon wave and T wave inversions in the anterior leads Echocardiography indication performed when structural heart disease is suspected or known Telemetry to monitor for dysrhythmias Differential Seizure differentiating factor bilateral tongue biting prolonged confusion after consciousness is regained Treatment Treatment is guided towards the underlying cause of syncope vasovagal syncope if low risk patient with no lab abnormalities patient can be discharged cardiogenic syncope admission to the telemetry unit for further diagnostic work-up (e.g., echocardiography) Complications Fractures