syncope a diagnostic algorythm 2000 17th nov 2001

History

• Yield 45-50%• Position of the patient• Precipitating factors• Presyncopal

symptoms• Syncope detail• Duration of attack• Post syncopal

symptom

• Associated symptoms– Chest pain

– Dyspnea

– Low back pain

– Palpitation

– Headache

• Medical history• Medicine history

Physical examination

• Vital signs– Pulse in both arm– BP, Postural BP– Temp

• Carotid massage• Cardiological examination• Neurological examination• External injury signs

Carotid massage

• Position supine and repeat in sitting and standing if negative in vasodepressor type

• Duration of massage 6-10sec• 15 sec difference between one to other side• ECG and BP monitoring• Complication

– Prolonged a systole– Ventricular fibrillation– Transient or permanent neurologic deficit– Sudden death

Investigation

• Blood – Blood glucose level

– Hb, PCV

– Electrolyte

– Cardiac enzyme

• Electrophysiology– ECG

– Holter monitoring

– Electrophysiological studies

– EEG

• Imaging– Chest X ray

– CT; brain, Chest ,abdominal

– Brain MR/MRI

– Ventilation perfusion scan

• Tilt table test

• Stress test

• Echocardiography

Blood Tests

• Yield 2-3%• Routine use is not recommended• Only if they are specifically suggested by the

results of the history or physical examination. • Pregnancy testing should be considered in

women of child-bearing age, especially those for whom tilt-table or electro physiologic testing is being considered

ECG

• Yield 5%

• Associated finding : 50%– Bundle branch block– Bifascicular block– Old MI– Ventricular Hypertrophy

• Cost effective investigation

Stress ECG

• Low yield 1%

• Indication– For exercise induced arrhythmias– Exertional syncope– Ischemia

Signal averaged ECG

• High sensitivity and specificity

• Inducible sustained ventricular tachycardia

• When CAD and VT is suspected

• As screening test for EP study

Prolonged ECG

• Yield Low– For 12 hour monitoring

– 4% symptomatic arrhythmias

– 17% no arrhythmia with symptoms

– 80% had a symptomatic arrhythmias

– 24 hour -> 14.7%

– 48 hours -> 11.1%

– 72 hours-> 4.2%

• Indication– Arrhythmic syncope

brief loss of consciousness no prodrome, palpitation, any posture

– Unexplained cause

– Heart disease

– Abnormal ECG

Loop ECG monitoring

• Long term monitoring days to months

• Yield24-47%

• Indication– Recurrent syncope – Normal heart

Electrophysiological study

• Indication– Known heart disease– Abnormal ventricular function– Abnormal ECG or Holter monitoring

• Bundle branch block

• Isolated conduction disease

• Ventricular tachyarrhythmias

Echocardiography

• Indication – Heart disease– Arrhythmias– Abnormal ECG

• Yield 5-10%

• 10 times more costly

Tilt table testing

• Yield– Passive 49% (26-90%) – Isoproterenol 64% (39-87%)

• Response– Two third cardioinhibitory– One third vasodepressor

• Protocols variable– Duration 5-60min– Tilt angle 60-90 degree– Isoproterenol dose 1-2micgm/min

Tilt table testing

• Sensitivity– 67-89% in Neurocardiac syncope

• Specificity– 90% for passive testing– 75% for Isoproterenol testing

• Reproducibility– 67-85%

Neurologic testing

• EEG– Poor yield– HO seizure

• CT brain– Low yield– Focal neurologic

signs

• Neurovascular studies– Doppler– Angiogram– Low yield in

unselected cases– VBI

Group A Neuro-circulatory

A. Diagnosed by History

and Examination

– Neurocardiac

– Orthostatic

– Situational

– Drug induced

B. Idiopathic

– Tilt table

– Loop monitor

– EP

– EEG

Group B Cardiac

A. Obstructive

– Echocardiogram

– Cardiac cath

– Lung scan

B. Arrhythmic

– Holter

– Loop Monitor

– EP study

Group C Neurological

A.Seizure

– EEG

– CT/MR

B. CVA

– Doppler

– CT/MR

– Angiography

S y n co p e D ia g n o stic A lg o r ith m

T reatNeu rocard iacO rth os ta tic

S itu a tion a l/D ru g

Diagnosed

T ilt tableL oop

E EG /E PP sy

Unknow n

Norm al Exam ination

EchoS tressC ath

OBS

HolterS tressL oopE P

Arrhythm ic

Cardiac

EEGCT/M R

Seizure

DopplerCT/M RA ng io

CVA

Neurological

HistoryExam ination

ECG