What is the most important etiology to rule out? C.L.I.P.S. SYNCOPE (1) Etiology 45%: Neurally mediated (carotid sinus syndrome, situational, vasovagal) 20%: Cardiogenic (arrhythmia, structural disease) 10%: Orthostatic (meds, postural tachycardia syndrome, autonomic failure, volume depletion) Others: unexplained or other non-traumatic causes (seizure, Neurogenic, Psychogenic, intoxication, metabolic) Diagnosis/Workup Standardized approach: ↓ admission, costs and testing History, history history!!! (check if really syncope, if with CV hx and for other clues re etiology; FHx of sudden death?) The BIG THREE: Hx and PE, Orthostatic vital signs, ECG. Orthostatic hypotension: ↓ SBP to <90mmHg, ↓ SBP by 20mmHg, ↓DBP by 10mmHg. Labs and Imaging: only as necessary. Risk stratification Low risk: no admission if ALL are met - age <50, no hx of CV dx, normal ECG, hx consistent with neurally mediated or orthostatic cause, normal cardiac exam High risk: admission for monitoring and further work up - everything else; including severe anemia, abnormal electrolytes, hypotension, and family hx of sudden death. What is the most important etiology to rule out? Cardiogenic. Associated with increased morbidity and mortality. Mortality rate OVERALL of 8.4% in 1 year, 1/3 of cases from cardiovascular (CV) causes. Updated 6/18 MChungtuyco

Common meds associated with orthostatic syncope: C.L.I.P.S. Common meds associated with orthostatic syncope: Anti-arrhythmics Anti-HTN Macrolide Antiemetics Antipsychotics TCAs BPH medications Work up Cardiogenic: Echocardiogram, Holter monitoring, event monitor; consider implantable loop recorder, exercise stress testing Non cardiogenic: Carotid sinus massage, Head tilt testing (differentiates neurally mediated vs orthostatic) Treatment Neurally mediated: avoid precipitating factors, counter-pressure (squat, cross legs). Meds with no clear benefit. Orthostatic hypotension syncope: counter-pressure, education; consider midodrine or fludrocortisone. Cardiogenic: treat etiology. Other pearls: Sudden onset, occurs in supine position, with palpitations/chest pain: likely cardiogenic. Sx with position change or prolonged standing, precipitated by certain activities, preceded by autonomic prodrome (abdominal pain, nausea, vomiting): likely neurally mediated vs orthostatic. Frequent and prolonged syncope: consider psychogenic.