Good Morning!Dr. Farjad Ikram

House Officer, CardiologyShalamar Hospital

SYNCOPE

◈ Understand the definition of syncope

◈ Know the different etiologies of syncope

◈ Risk stratification and when to admit

Objectives

1.case scenario

Uzma Khan / 21 years old / Female / StudentPresented in OPD with H/O fainting (2 episodes in 1 week)First episode occured 4 days ago when she stood up after eating a large meal. She was caught by a friend during her fall and only had an scraped elbow. The spell lasted for 10 seconds. There were no jerking movements or loss of bowel or bladder control. She woke up with some confusion about what happened but there was no cognitive impairement.She reported lightheadedness before loss of consciousness.Second episode occured yesterday and was similar to the first but occured on a hot day while she was out on a picnic.

Case Scenario

There is a no significant past medical history.There is no family history of epilepsy or sudden death.There is no history of any drug use.There is a non-smoker and non-alcoholic.On examination, her findings are as follows:• Pulse - 70 b/m, regular• B.P - 110 / 70 mmHg• SpO2 - 99% on room air• R.R - 16 b/m, Afebrile• CBC, RFTs and serum electrolytes are within

limits.

Case Scenario

• S1 + S2 + 0• Normal vesicular

breathing• Abdomen is non-tender• GCS 15 / 15

Case ScenarioECG shows sinus rhythm of 75-100 b/m, normal axis, normal PR and QT intervals, with no changes suggestive of ischemia or hypertrophy.

What is the most likely diagnosis?Vasovagal syncope

What is the next best diagnostic test?Orthostatic vitals or tilt table test.

What is the next best step in therapy?Adequate hydration and avoidance of triggers.

Case Scenario

2.introduction

Syncopeis a symptomnot a disease

“Syncope is the abrupt

transient loss of consciousness (TLOC) associated with absence of posture,

followed by complete and usually rapid spontaneous recovery.

Definition

“The underlying mechanism is

hypoperfusion of cerbral cortex.

Definition

SyncopeTransient loss of

consciousness that is abrupt and short,

followed by complete spontaneous

recovery.

Syncope vs Pre-syncope

Pre-syncopeSensation of

impending loss of consciousness

or lightheadedness often accompanied by blurred vision.

Similar etiologies and work-up.

Differentials

◈Syncope (TLOC with loss of posture, spont. recovery)

◈Drop attack (sudden loss of posture without TLOC)

◈Coma (TLOC without spont. recovery)

◈Seizures (tonic-clonic movements that start with TLOC with post-ictal recovery period)

Important to distinguish syncope from other diseases.

Seizure vs Syncope

epidemiology

prevalence of syncope is 24% among

people ofage > 70 years

incidence of syncope is 25 per 1000 people

each year

3% ER visits / year

34% people experience syncope at least once in a lifetime

5% admissions / year

Most common demographic – elderly female

E T I O L O G Y

Cardiovascular

15%

Neuro-cardiogenic

( vaso-vagal )60%

Orthostatic hypotension

15%

Other (<10%): neurologic, metabolic, psychological

2.evaluation

Evaluation and work-up

◈History (including past history and family history of sudden death)

◈Physical examination (including orthostatics)◈Review of previous medications◈Account of an eye-witness of the syncope event

◈12 lead ECG◈CBC, RFTs, serum electrolytes◈Echo cardiography (rule out structural cardiac causes)

◈Risk stratification (admit the high-risk patients)

Work-up should determine who is at high-risk for a dangerous cardiac

event.

When to admit?

◈Evidence of structural heart disease◈ECG suggestive of rate and rhythm abnormalities◈Co-morbidities like anemia or electrolyte

disturbances◈Unclear etiology of syncope with high-risk

features:- heart failure- advanced age- multiple un-explained episodes◈Head CT is indicated only if the patient has

experienced focal neurological deficits or they experienced head trauma from the event.

Patients at high risk for cardiac mortality need cardiac work-up as an

inpatient.

Low risk patients

◈Single episode – No further work-up needed◈Multiple episodes – manage as an outpatient- Frequent episodes – consider loop recorder or Holter

monitoring

◈Tilt test (if vasovagal syncope is suspected)◈Carotid massage (if carotid sinus hypersensitivity is

suspected) - avoid if suspected TIA, carotid bruit present, past history

of CVA)

◈Rule out endocrine or metabolic causes

Patients with no evidence of high risk factors for cardiac mortality.

4.neuro-

cardiogeniccauses of syncope

Neuro-cardiogenic causes◈Vaso-vagal episode is a feeling of general

discomfort mediated by vagas nerve, often leads to syncope.

◈History of similar recurrent episodes in the past.◈Triggers:• Prolonged standing, Hot places• After or during urination (micturition syncope)• Emotional stress, Sensitivity to pain• Lack of sleep, Hunger• Fears: the sight of blood, height, spiders etc• Carotid Sinus Hypersensitivity (i.e. shaving, tight

collars)

Enhancement of parasympathetic

(vagal) tone

Decrease in heart rate

and contractility

Decrease in cardiac output

Vasovagal refelxTriggers stimulate brainstem nuclei.

Withdrawal of sympathetic tone

Peripheral vasodilation

Decrease in systemic

blood pressure

SYNCOPE

Vasovagal SyncopeDiagnosis:◈Made in context of history

and exclusion of cardiogenic causes of syncope

◈Tilt table test:• The patient strapped flat on a

bed and monitored with ECG and a BP monitor. Bed then creates a change in posture from lying to standing for 20-30 min to induce syncope.

◈Other: • Implantable loop recorder• Holter monitoring

Treatment of vasovagal syncope

◈Counsel patients to avoid predisposing triggers◈Maintain adequate hydration◈Volume expanders like fludrocortisone◈Vasoconstrictors like midodrine◈SSRIs have shown promise in some patients

◈In absence of any cardiac structural or rate/rhythm abnormalities, treatment can be done on outpatient basis.

◈Prognosis: Although neurally mediated syncope can be distressing for the patient and affects quality of life, the mortality rate is low.

Carotid Sinus Hypersensitivity◈Also called carotid sinus syncope.◈Manual stimulation of carotid sinus causes

vasovagal bradycardia and hypotension, sometimes syncope.

• Carotid baro-receptors are supplied by glosso-pharyngeal nerve which synapses with nucleus tractus solitarii in medulla oblongata.

◈This classically presents as a patient who has "fainted" on several occasions while shaving.

◈Czermak-Hering test: carotid sinus massage is used to diagnose carotid sinus syncope. Avoid in elderly.

◈Treatment is permanent pacemaker in cardio-inhibitory forms of CSH i.e. with severe bradycardia.

5.cardiogeniccauses of syncope

Cardiogenic causes◈Dysrhythmias (most common) - Bradycardia i.e. Sick Sinus syndrome, Bezold-Jarisch reflex, Adam Stokes

syndrome - Tachycardia (VT, WPW syndrome)◈Outflow obstruction - Aortic stenosis - Hypertrophic obstructive CMP◈Systolic dysfunction - Aortic or mitral regurgitation - Ventricular dysfunction (MI, myocarditis)◈Diastolic dysfunction - Mitral stenosis - Pericardial effusion / tamponade - Constrictive pericarditis

6.orthostatic

hypotension

Orthostatic hypotension◈Common condition. In about 50% of admitted elderly patients.◈Most marked after meal, exercise, high temperature,

and in early morning.

◈It is a change in blood pressure with change in posture

• Reduction in systolic BP of 20 mmHg on standing, or• Reduction in diastolic BP of 10 mmHg on standing

◈Occurs because of delayed vasoconstriction of the lower body blood vessels, causing decreased venous return to heart. This leads to decreased cardiac output and syncope.

Causes of postural hypotension◈Age related blood vessel stiffness◈Hypovolemia (dehydration or hemorrhage)◈Prolonged bed-ridden◈Anti-hypertensives esp. alpha blockers◈Anti-depressants i.e. tricyclics, MAOIs◈Alcoholism◈Addison’s disease◈Pheochromocytoma◈Autonomic neuropathy• In diabetes, multiple sclerosis, Parkinson’s disease• Primary autonomic neuropathy (Bradbury-Eggleston

syn.)

Treatment of postural hypotension◈Lifestyle measures◈Stop offending drugs◈Compression stockings◈Head-of-bed elevation◈Fludrocortisone for fluid retention in adrenal

insufficiency◈Sympathomimetic vasoconstrictors like Midodrine◈Treat underlying cause

7.other causesof syncope

Other causes◈Hypoglycemia◈Pulmonary embolism◈Aortic dissection◈Post prandial syncope◈Transient ischemic attack (TIA)◈Subclavian steal syndrome◈Psychogenic (Psuedo-syncope)• usually Conversion disorder

Thank you for your time!Any questions?