The Significance of Syncope The only difference between syncope and sudden death is that in one you wake up. 1 1 Engel GL. Psychologic stress, vasodepressor syncope, and sudden death. Ann Intern Med 1978; 89: 403-412.
Neurally-mediated syncope Absence of cardiological disease Long history of syncope After sudden unexpected unpleasant sight, sound, smell or pain Prolonged standing or crowded, hot places Nausea, vomiting associated with syncope During the meal or in the absorptive state after a meal With head rotation, pressure on carotid sinus (as in tumors, shaving, tight collars) After exertion Syncope due to orthostatic hypotension After standing up Temporal relationship with start of medication leading to hypotension or changes of dosage Prolonged standing especially in crowded, hot places Presence of autonomic neuropathy or Parkinsonism After exertion Cardiac syncope Presence of definite structural heart disease During exertion, or supine Preceded by palpitation Family history of sudden death Cerebrovascular syncope With arm exercise Differences in blood pressure or pulse in the two arms
1 Day SC, et al. Am J of Med 1982;73:15-23. 2 Kapoor W. Medicine 1990;69:160-175. 3 Silverstein M, Sager D, Mulley A. JAMA. 1982;248:1185-1189. 4 Martin G, Adams S, Martin H. Ann Emerg Med. 1984;13:499-504. Some causes of syncope are potentially fatal Cardiac causes of syncope have the highest mortality rates The Significance of Syncope
Structural Cardiac Abnormalities Hx of MI / Ischemic injury CHF / decreased EF Valvular abnormalities Outflow obstruction Wall motion abn. Bradycardia Sick sinus AV block Tachycardia VT SVT Long QT Syndrome Cardiac Rhythm Abnormalities
Test/ProcedureYield based on mean time to diagnosis of 5.1 months 7 History and Physical (including carotid sinus massage) 49-85% 1, 2 ECG 2-11% 2 Electrophysiology Study without SHD* 11% 3 Electrophysiology Study with SHD 49% 3 Tilt Table Test (without SHD) 11-87% 4, 5 Ambulatory ECG Monitors: Holter 2% 7 External Loop Recorder (2-3 weeks duration) 20% 7 Insertable Loop Recorder (up to 14 months duration) 65-88% 6, 7 Neurological (Head CT Scan, Carotid Doppler) 0-4% 4,5,8,9,10 *Structural Heart Disease MRI not studied 1 Kapoor, et al N Eng J Med, 1983. 2 Kapoor, Am J Med, 1991. 3 Linzer, et al. Ann Int. Med, 1997. 4 Kapoor, Medicine, 1990. 5 Kapoor, JAMA, 1992 6 Krahn, Circulation, 1995 7 Krahn, Cardiology Clinics, 1997. 8 Eagle K,, et al. The Yale J Biol and Medicine. 1983; 56: 1-8. 9 Day S, et al. Am J Med. 1982; 73: 15-23. 10 Stetson P, et al. PACE. 1999; 22 (part II): 782.
Arch aortogram initially shows apparent absence of left vertebral artery. However, delayed imaging on the same patient, the left vertebral artery (green) fills retrogradely to supply the left subclavian artery, (confirming left subclavian steal phenomenon secondary to a severe stenosis of the proximal left subclavian artery) (b) Delayed Image (a) aortogram Subclavian Stenosis Subclavian Stenosis
Your Patient 21 year old college student who keeps blacking out without seizure activity… Evaluated in the ED this afternoon, phenytoin (Dilantin) level is normal... What other tests do you want?… What are these spells (? Seizures ?) If so, what type of seizure is it (? And, does it matter ?) How do you know they are not in status epilepticus? What should your evaluation include? How does the AED level help direct your plan? What will you do if seizures continue in spite of management?
Will it happen again? (risk of recurrence) If it does…
Absence Warning (aura) Often no Duration 30-120 sec 10-20 sec Occur (#) 1-3/day 10-20/day Automatisms Often Occas. Amnestic (for spell) Partially Totally Post-ictal (tired) YES no Focal abn (ex or scan) Often no Family hx no YES Complex Partial
What you should now know: SPELLS of… Vision, consciousness, weakness, etc… Avoid terms such as Blacking Out, Passing Out, Fell Out Syncope definition, evaluation, prognosis Epilepsy, Tx & eval of epilepsy, Control of epilepsy Normal AED Level Therapeutic AED level Toxic Level Post-ictal Petit Mal (Absence) sz Convulsive syncope Tussive Syncope & Micturation Syncope Hypoglycemia spells Drop Attacks due to V-B Insufficiency or Subclavian Steal Carotid dz (? Causing syncope/spells with LOC) Bank Robberies and other complex activity during seizures or somnambulism