Syncope From Greek meaning pause
Amal Mattu Article on EKG findings to check for all syncope patients
Cardiac Causes Obstruction to flow Subaortic stenosis Aortic valve stenosis Mitral valve stenosis Atrial myxoma (rare) Pulmonic valve stenosis Hypertrophic cardiomyopathy Dilated cardiomyopathy Restrictive cardiomyopathy Pericardial tamponade Severe congestive heart failure Vascular disease Pulmonary emboli Pulmonary hypertension Acute myocardial infarction Air embolism Aortic dissection/leaking aortic aneurysm Subclavian steal syndrome Dysrhythmias Tachydysrhythmias Supraventricular tachycardia Ventricular tachycardia Ventricular fibrillation Atrial fibrillation with fast conduction Wolff-Parkinson-White syndrome Prolonged QT syndrome Brugada syndrome Bradydysrhythmias Atrioventricular block Atrial fibrillation with slow conduction Sick sinus syndrome Pacemaker malfunction Noncardiac Causes Vasodepressor (vasovagal, neurocardiogenic) Situational Micturition Post-tussive Swallow Defecation Valsalva (weightlifters) Carotid sinus sensitivity Orthostatic Anemia/GI bleed Dehydration Central nervous system / neurologic Seizure (excluded by most syncope studies) Neuralgias (trigeminal, glossopharyngeal) Neurologic (TIA, strokes, migraines [rare]) Subarachnoid hemorrhage Subdural/epidural hemorrhage Metabolic / toxic Hypoglycemia Hypoxia Drug-induced Carbon monoxide poisoning Chemical / toxic gas exposure Carotid sinus sensitivity Infectious agent Psychogenic Somatization disorder Anxiety disorder Conversion disorder Panic disorder Hyperventilation Breath-holding spells Causes of collapse2 Differential diagnosis Clinical clues
Hypoxia, hypoglycaemia Should be picked up in primary survey Do not forget the glucose Epilepsy* Previous history, postictal period Affective (psychological) History of anxiety or panic disorder, hyperventilation Dysfunction of brain stemfor example, vertebrobasilar transient ischaemic attack, basilar migraine Cerebellar signs on neurological examination Heartfor example, ischaemic heart disease Recent chest pain, history of myocardial infarction Embolipulmonary embolism Pleuritic chest pain, dyspnoea, calf pain, or swelling Aortic obstructionfor example, stenosis, hypertrophic obstructive cardiomyopathy (HOCM) Precipitated by exertion, cardiac murmur on auscultation Rhythm disordersfor example, sick sinus syndrome, complete heart block May be picked up on primary survey if heart rate <50, history of ischaemic heart disease Tachydysrhythmiasfor example, SVT, VT, long QT syndrome History of palpitations, may be picked up on primary survey if heart rate >100, <5 s prodromal period Vasovagal* Prodrome of nausea, dizziness, yawning, sweaty ENTfor example, Ménières disease, acute labyrinthitis, benign paroxysmal positional vertigo History of vertigo, deafness, tinnitis. nystagmus on neurological examination Situationalfor example, fright, micturition, deglutition, defaecation May be apparent from history Sensitive carotid sinus Precipitated by head movement Ectopic pregnancy** History of abdominal pain, amenorrhoea, PV bleeding, positive pregnancy test Low vascular tone Subclavian steal** Precipitated by upper arm exertion DRUGSfor example, antihypertensives, sympathetic blockers causing postural hypotension* Elderly patient on multiple drugs Postural fall in blood pressure
*Common causes In seconds preceding LOC there is a loss of lateral gaze, possibly dizziness Vascular/Cardiac-rhythmic, obstructive, metabolic, meds Vasomotor-consider AAA, ectopic, and other sources of occult bleeding Cardiac-if exercise induced, think IHSS, valvular disorder, or subclavian steal Stokes-Adams: heart block, syncope, vertigo Cough, micturition, post-prandial Place pregnant women in LLR High risk if >60 y/o or Cardiac history CHF on exam assoc. c high risk 12 Lead EKG (even in the young for prolonged QT and Brugada), consider CBC or guiac and pregnancy test. Admit high risk or young pts c syncope during exercise (ACEP Clinical Guidelines) Neurally Mediated Syncope associated with inappropriate vasodilatation, bradycardia or both. a. Vasovagal syncope is often associated with a sensation of increased warmth and may be accompanied by nausea. It may occur after exposure to an unexpected or unpleasant sight, sound or smell, fear, severe pain, emotional distress and instrumentation. It may also occur in association with prolonged standing or kneeling in a crowded or warm place or on exertion (all three latter scenarios may also be due to autonomic failure) b. Situational syncope occurs during or immediately after coughing, micturition, defecation or swallowing. Syncope associated with throat or facial pain, however, may be due to glossopharyngeal or trigeminal neuralgia c. Carotid sinus syncope can be associated with neck pressure (shaving, tight collar) or head turning Orthostatic Syncope Occurs when there is documented hypotension associated with syncopal or presyncopal symptoms. According to ECS guidelines, orthostatic blood pressures are recommended to be taken after five minutes of being supine. A decrease of more than 20mm Hg in the systolic pressure is considered abnormal as is a drop in pressure below 90mm Hg independent of the development of symptoms. Neurologic Syncope Neurologic causes of apparent syncope include seizures, TIAs, migraine headaches and subclavian steal syndrome. Confusion after “syncope” that lasts more than five minutes, tongue biting, incontinence, epileptic aura suggest this diagnosis. A significant differential in the blood pressure of the two arms suggests subclavian steal Cardiac-Related Syncope The major categories of cardiac disease associated with syncope are ischemia, valvular
and arrhythmic. Accuracy and Quality of Clinical Decision Rules for Syncope in the ED A MA (Ann Emerg Med 2010;56(4):362)
QT syndrome suggested by notched or bifid T waves in V2-V4 Risk Stratification for Syncope Martin et al 252 derivation, 374 validation
- Age greater than 45 y/o
- History of Vent dysrhythmias
- History of CHF
- Abnormal EKG
No risk one year mortality 1.1% 27.3% with three or more risk factors (Ann Emerg Med 1997Apr 29(4)459) All patients with positive CTs in one study had a witnessed seizure or an alteration of their neurologic exam (Ann Intern Med 1997 Jun 15;126(12):989-996) Eur Heart J 2003 24;811-819
- Age>65
- Cardiovascular Disease
- Previous clinical or lab dx of structural heart dis, valvular dis, and primary myocardial dis
- Previous Hx of CHF
- Previous Dx or clinical evidence of PVD
- Previous Dx of stroke or TIA
- Syncope without a prodrome (drop syncope)
- Abnormal EKG
- A-fib, a-flutter, SVT, MFAT, frequent PVC, sustained or non-sustained V-tach or paced rhythms
- Mobitz types I and II, 3rd degree and bundle branch blocks
- Left axis deviation, LVH, old MI
- ST-T abnormality c/w myocardial ischemia
If you had 2 or more, much higher mortality ACEP Level B A hx of CHF or ventricular arrhythmias Associated CP or symptoms c/w ACS Evidence of CHF or valvular heart dis. on physical exam ECG findings of ischemia, BBB, prolonged QT or arrhythmiaLevel C Age older than 60 years Hx of CAD or congenital heart diseases Family Hx of sudden death Exertional syncope in younger patients
CLINICAL CLUES TO CAUSE OF SYNCOPE
The following list was adapted from Jeff Mann Jeff Mann’s Clues to Syncope
- Sudden syncope at rest when non-erect suggests a cardiac arrhythmia or atrial myxoma
- Sudden syncope on exertion suggests aortic stenosis, hypertrophic obstructive cardiomyopathy
- Preceding “lightheadedness” prodrome with sweating and nausea when erect that has a slow, progressive onset suggests vasovagal syncope (orthostatic hypotension would not likely have the sweating and nausea and is another cause of syncope preceded with lightheadedness)
- Preceding palpitations suggests a cardiac arrhythmia
- Preceding or accompanying dyspnea suggests pulmonary embolism (PE), tension pneumothorax, cardiac tamponade and air embolism
- Preceding chest pain suggests myocardial ischemia, PE, cardiac tamponade, dissecting aneurysm, and mitral valve prolapse
- Preceding or accompanying back pain suggests dissecting aortic aneurysm or leaking abdominal aortic aneurysm
- Preceding or accompanying abdominal pain suggests a leaking abdominal aneurysm or ectopic pregnancy
- Occurring when turning head side to side, shaving or with neck compression suggests carotid sinus syncope
- Occurring when exercising an upper arm suggests subclavian steal syndrome
- Occurring during (or immediately after) coughing, laughing, vomiting, swallowing, urination, defecation, combing hair or stretching suggests situational syncope
- Occurring after prolonged standing suggests vasovagal syncope
- Occurring after an emotional upset suggests either vasovagal syncope, prolonged QT syndrome or torsades de pointes
- Recent illicit drug use suggests a cardiac arrhythmia, air or foreign body embolism
- Syncope associated with a sudden headache suggests a subarachnoid hemorrhage
- Recent neurologic symptoms suggests a brain stem stroke, vertebrobasilar insufficiency, basilar migraine, carotid or vertebral artery aneurysm or aortic dissection
- Recent vaginal insufflation suggests an air embolism
- Recent black stools suggest a GI bleed
- Recent fluid loss (vomiting, diarrhea, sweating) or poor intake suggest hypovolemia and orthostatic hypotension or Addisonian crisis
- Postprandial syncope is associated with a recent meal
- Polypharmacy or sildenafil suggest orthostatic hypotension as a cause of syncope
- A history of known cardiac ischemia or structural heart disease suggests a cardiac arrhythmia or a drug-induced arrhythmia or cardiac valvular dysfunction
- A history of a mechanical heart valve can be associated with syncope caused by valve-related thrombosis
- Cancer, obesity, pregnancy, recent surgery or trauma, prolonged bed rest and prior thromboembolic events suggest the presence of a pulmonary embolism as the cause of syncope.
- A history of autonomic dysfunction manifested by impotence, anhydrosis, sphincter dysfunction can be associated with orthostatic hypotension-related syncope.
The most accurate decision rule in the derivation set gave two points if the patient reported waking with a cut tongue, and one point each if there was a report of abnormal behavior, loss of consciousness with emotional stress, post-ictal confusion, head turning to one side during loss of consciousness, or prodromal deja vu or jamais vu; two points each were deducted for any reported presyncope, loss of consciousness with prolonged standing or sitting, or diaphoresis prior to an episode. (J Am Coll Card 40(1):142, July 2002) San Francisco Syncope Rule Derivation Set only (Annals 2004, Feb. 43:2) There were 684 visits for syncope, and 79 of these visits resulted in patients’ experiencing serious outcomes. Of the 50 predictor variables considered, 26 were associated with a serious outcome on univariate analysis. A rule that considers patients with an abnormal ECG, a complaint of shortness of breath, hematocrit less than 30%, systolic blood pressure less than 90 mm Hg, or a history of congestive heart failure has 96% (95% confidence interval [CI] 92% to 100%) sensitivity and 62% (95% CI 58% to 66%) specificity. If applied to this cohort, the rule has the potential to decrease the admission rate by 10%. (Ann Emerg Med 2006;47(5):448) failed in revalidation (Ann emerg med 2008;52:151)
Presyncope
These patients seem to do as bad as syncope patients (Ann Emerg Med 2015;65(3):268)