Seizure syncope & drop attacks

Mark KeezerR5 Neurology

ELS July 13, 2011

Seizure versus

syncope!?All of the

above?

Outline

• Brief overview of epileptic seizures

• Syncope: an organized approach

• Seizure versus syncope– An approach to the patient

• Further differentials diagnoses for your consideration.

• What is an epileptic seizure?

• What is epilepsy?

• Epilepsy:– Etymology: epilepsia (Gk): “to seize upon”

– Hughlings Jackson circa 1870• “an excessive and disorderly discharge of cerebral

nervous tissue on muscles”

ILAE definitions

• Epileptic seizure:– “transient occurrence of signs and/or symptoms due to

abnormal excessive or synchronous neuronal activity in the brain”

• Epilepsy:– “Disorder of the brain characterized by an enduring

predisposition to generate epileptic seizures and by the neurobiologic, cognitive, psychological and social consequences of the this condition. The definition of epilepsy requires the occurrence of at least one epileptic seizure”

1981 ILAE Seizure Classification• Focal onset

a. Simple partialb. Complex partialc. Partial seizures evolving to secondarily generalized

• Generalized Onseta. Absenceb. Myoclonicc. Clonicd. Tonice. Tonic-clonicf. Atonic

• What does a GTC actually look like?

Generalized Tonic Clonic Seizure• … the seizure strikes "out of the blue," … beginning with a sudden

loss of consciousness and a fall to the ground.• The initial motor signs are a brief flexion of the trunk, an opening

of the mouth and eyelids, and upward deviation of the eyes. The arms are elevated and abducted, the elbows semiflexed, and the hands pronated.

• These are followed by a more protracted extension phase, involving first the back and neck, then the arms and legs.

• There may be a piercing cry as the whole musculature is seized in a spasm and air is forcibly emitted through the closed vocal cords…

• This is the tonic phase … and lasts for 10 to 20 seconds.

Generalized Tonic Clonic Seizure

• … there is a mild generalized tremor, which is, in effect, a repetitive relaxation of the tonic contraction.

• … begins at a rate of 8 per second and coarsens to 4 per second; then it rapidly gives way to brief, violent flexor spasms that come in rhythmic salvos and agitate the entire body.

• Autonomic signs are prominent: the pulse is rapid, blood pressure is elevated, pupils are dilated, and salivation and sweating are prominent; bladder pressure may increase six-fold during this phase.

Generalized Tonic Clonic Seizure • The clonic jerks decrease in amplitude and frequency

over a period of about 30 seconds. The patient remains apneic until the end of the clonic phase…

• In the terminal phase of the seizure, all movements have ended and the patient lies still and limp in a deep coma…

• Breathing may be quiet or stertorous. • This state persists for several minutes, after which the

patient opens his eyes, begins to look about, and is obviously bewildered and confused and may be quite agitated.

Video

• What is syncope?

• Syncope:– Etymology: synkoptein (Gk): “to cut off”

– Abrupt, transient, and self-limiting loss of consciousness associated with loss of postural tone, caused by a sudden fall in cerebral perfusion.

Video

• How frequent is convulsive syncope?

Convulsive syncope

• Lempert et al. studied 42 patients with syncope– Induced by hyperventillation, orthostasis and valsalva

• 90% with myoclonus– Multifocal arrythmic jerks in proximal and distal muscles– Generalized myoclonus

• 79% with head version, oral automatisms and righting movements

• 60% reported visual and auditory hallucinations• 1 lateral tongue bite!

Convulsive syncope

• Intermittent posturing of brainstem origin– Dis-inhibition in the context of cortical hypo-

activity due to transient cerebral hypoxia

What are the presumed levels of these lesions?

• What are the causes of syncope?

• Do you have an organized approach?

Mechanistic classification of syncope

1. Neurally mediated

2. Orthostatic hypotension

3. Cardiopulmonary disease

4. CNS syncope

Neurally mediated (1/4)

• Vasovagal syncope • Carotid sinus syncope• Situational syncope• Atypical causes– Glossopharyngeal neuralgia.

Vasovagal Syncope• Aka vasodepressor syncope

– Loss of sympathetic vascular tone coupled with heightened vagal activity on the heart.• Vasodilate while bradycardic

– Transient but excessive sympathetic activity may paradoxically vasodilate in intramuscular and splanchnic vessels?

– Neurocardiogenic component?• Initial vigorous ventricular contractions lead to deficient filling therefore

prompting the “empty-heart syndrome”

• Younger individuals, women, migraineurs?• Often in the context of heat, hunger, pain, strong emotion.

Carotid Sinus Syncope

• Nerve of Hering, branch of CN IX– Vagal-mediated decrease in BP

• Episodes precipitated by– Tight collar– Turning of the head– Shaving over the sinus

• Older men– Atherosclerosis?

Situational syncope

• Diminished venous return– Cough– Swallow– Micturition– Defecation– Weight-lifting– Hairbrushing– Stretch.

Glossopharyngeal Neuralgia

• Paroxysms of pain localized to the base of the tongue, pharynx, larynx or ear– Beginning in the 6th decade

• 2% associated with syncope– Mediated by activation of the dorsal motor nucleus

of the vagus by the nucleus solitarius

• Deglutitional syncope– Syncope post forceful swallow!

Orthostatic hypotension (2/4)

• Primary

• Secondary– Including shock • Dehydration• Hemorrhage• Sepsis…

– & dysautonomia

Vascular Prolonged bedrest Hypothalamic lesions (including NMO)Trauma Spinal cord trauma (or any severe myelopathy)

Autoimmune & Inflammatory

Guillain Barre syndrome CIDP Pure pandysautonomia Amyloidosis neuropathy LEMSMetabolic & Endocrine

Diabetes mellitusInherited Fabry’s diseaseDrug & Toxin Antihypertensive medications L-dopaDegenerative Idiopathic orthostatic hypotension Multisystem atrophy Parkinson’s disease

Cardiopulmonary disease (3/4)

• Arrythmia– AV block– Long QT– Some degree of PEA

• Structural disease– Valvular disease (AS)– Acute MI– Pericardial tamponade– Pulmonary embolism– Pulmonary hypertension.

CNS syncope (4/4)

• Ictal bradycardia– Cingulate gyrus, insular cortex, amygala– Potentially related to SUDEP

• Acute increase in ICP– Colloid cyst of the 3rd ventricle

• Subclavian steal syndrome– Atherosclerosis– Cervical rib– Takayasu’s arteritis

• Hyperventilation.

Seizure vs Syncope

Often not present in cardiopulmonary

syncope!

• 539 patients diagnosed with seizure or syncope– Completed a 108 item

questionnaire

– Score ≥1 is 94% sensitive and specific for seizures

Examination

• Vitals– Orthostatic BP and HR

• Supine to standing• 30mmHg at 3 mins, etc…

– Carotid massage• With pt’s neck extended & rotated away from you, massage below

the angle of the jaw, lateral to the thyroid cartilage but no longer than 5 minutes

• To reproduce presyncope• Beware of any bruits

– Cardiac and neurologic examinations.

Investigations

• CBC, SMA7, LFT…– Exclude anemia, infection, electrolyte disturbances, or

renal and liver dysfunction.• EKG, cardiac monitor• TTE?• D dimer … V/Q scan or PE study

• Suspected seizure, dysautonomia or CNS syncope?

EEG insensitivity

• In those with new onset seizures– 50% of routine EEG’s reveal epileptiform

abnormalities.

• Retrospective study– 517 EEGs, between 2003-2007– 57 (11%) were “abnormal”• No clear epileptiform abnormalities• 5 EEGs resulted in further investigations• 1 pt treated with PHT (despite Neurology’s advice!)

Transient atonia orloss of consciousness

• Differential diagnosis– Seizure– Syncope

– Psychogenic functional disorder

– Basilar migraine– Vertebrobasilar TIA– Vertiginous attack

• Otolithic catastrophe of Tumarkin– Cataplexy

– Paroxysmal dyskinesia– Hyperekplexia.

Summary• Brief overview of epileptic seizures

• An approach to syncope– Neurally mediated– Orthostatic hypotension– Cardiopulmonary disease– CNS syncope

• Seizure versus syncope– An approach to the patient

• Differential diagnosis.

Bad Emerg consults…

bring it on!

References• Adams and Victor’s Principle of Neurology 8th Edition.• Crompton DE, et al. The borderland of epilepsy: clinical and molecular features of

phenomena that mimic epileptic seizures. Lancet Neurol 2009;8:370-81.• Fisher RS, et al. Epileptic seizures and epilepsy: Definitions proposed by the ILAE and

IBE. Epilepsia 2005;46:470-2.• Krumholz A et al. Practice parameter: evaluating an apparent unprovoked first

seizures in adults (an evidence-based review). Neurology 2007;69:1996-2007.• Lempert T, et al. Syncope: a videometric analysis of 56 episodes of transient cerebral

hypoxia. Ann Neurol 1994;36:233-7.• McKeon A, et al. Syncope versus seizure. Lancet Neurol 2006;5:171-80.• Sheldon R, et al. Historical criteria that distinguish syncope from seizures. J Am Coll

Cardiol 2002;40:142-8.• Proposal for revised clinical and electroencephalographic classification of epileptic

seizures. Epilepsia 1981;22:489-501.• Soteriades ES, et al. Incidence and prognosis of syncope. NEJM 2002;347:878-85.