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Latest approach and treatment strategies for syncope DR SOFIAN JOHAR CONSULTANT CARDIOLOGIST AND ELECTROPHYSIOLOGIST RIPAS HOSPITAL AND GLENEAGLES JPMC BRUNEI DARUSSALAM... Syncope du

Latest approach and treatment

strategies for syncope

DR SOFIAN JOHAR CONSULTANT CARDIOLOGIST AND

ELECTROPHYSIOLOGIST RIPAS HOSPITAL AND GLENEAGLES JPMC

BRUNEI DARUSSALAM

SYNCOPE

• Syncope is a T-LOC due to transient global cerebral

hypoperfusion characterized by rapid onset, short duration, and spontaneous complete recovery

• Others (e.g laughter, weightlifting)

– Carotid sinus syncope

– Atypical forms

Syncope due to orthostatic

hypotension

• Primary autonomic failure

– Pure autonomic failure, multiple system atrophy,

Parkinson’s disease with autonomic failure, Lewy body dementia

• Secondary autonomic failure

– Diabetes, amyloidosis, uraemia, spinal cord injuries

• Drug-induced orthostatic hypotension

– Alcohol, vasodilators, diuretics, phenothiazines, depressants

anti-• Volume depletion

– Haemorrhage, diarrhoea, vomiting, etc

Cardiac syncope (cardiovascular)

• Arrhythmia as primary cause

– Bradycardia

• Sinus node dysfunction (including bradycardia/tachycardia syndrome)

• Atrioventricular conduction system disease

• Implanted device malfunction

– Cardiac: cardiac valvular disease, acute myocardial infarction,

ischaemia, HCM, cardiac tumours, pericardial disease, prosthetic valve dysfunction, congenital anomalies of coronary arteries

– Others: Pulmonary embolus, acute aortic dissection, pulmonary

hypertension

Prevalence of syncope

High prevalence 10-30 years

47% in females and 31% in males by age 15

• Reflex syncope most common

• Syncope from cardiovascular causes 2nd most common

How to diagnose – ask a few

questions!

• Was the loss of consciousness complete?

• Was the loss of consciousness with rapid onset and short duration?

• Did the patient recover completely and without sequelae?

• Did the patient lose postural tone?

If the answers are positive – likely syncope

If one or more negative – consider alternatives

Is it serious? Exclude cardiovascular

syncope

• Presence of definite structural heart disease

• Family history of unexplained sudden death or

Investigations

• Exclude structural heart disease – echo

• Exercise testing if symptoms related to exercise –

HOW TO PERFORM CAROTID SINUS

MASSAGE?

• Lying and supine

• Beat-to beat measurement of BP ideally

• Right carotid artery then left at level of cricoid cartilage for 5-10s

• Mixed

• Positive if symptoms reproduced

to very low levels after 1 min upright with little increase in HR despite the hypotension

Classical orthostatic hypotension

Tilt testing

• Reflex syncope (mixed

form) induced by tilt

testing

• in a 31-year-old (upper panel)

• in a 69-year-old patient (lower panel)

• Note the typical age

differences with a much steeper fall in BP in the

younger subject compared with the older subject

Indications for electrophysiological

testing

• Suspected intermittent bradycardia

– Pre-test probability is high if there is asymptomatic sinus bradycardia (<50bpm) or sino-atrial block

• Usually demonstrated by 12-lead ECG or ECG monitoring

– Sinus node recovery time  2s, corrected sinus node

recovery time  525ms

• Syncope in patients with bundle branch block

– History of syncope and prolonged His-ventricular interval – The progression rate to AV block at 4 years was 4, 12, and 24%, respectively, for patients with an HV interval <55 ms (normal), ≥70 ms and ≥100 ms

– Can add challenge with class I anti-arrhythmics e.g

flecainide

Example of marked

His-Purkinje system disease with a relatively normal PR interval Surface leads I, aVF, and V1 are shown with electrograms from the high right atrium (HRA), His bundle electrogram (HBE), and time lines (T) The QRS shows right bundle branch block and left anterior

hemiblock; the PR interval is minimally elevated at 205 ms, but the HV interval exceeds

100 ms Such a prolonged HV interval mandates a

pacemaker

Indications for electrophysiological

Treatment – primary arrhythmic cause

• Symptomatic sinus node disease – pacing

• Symptomatic AV block – pacing

• SVT – pharmacologic or ablation

• VT – drugs, implantable-cardioverter

defibrillator, ICDs – depending on presence or absence of structural heart disease

Overt pre-excitation

Typical flutter

UNEXPLAINED SYNCOPE in patients at

high risk of sudden cardiac death

• ICDs with or without medications

• Electrophysiological studies can be done if

diagnosis is unclear and e.g LVEF between 30 and 40%

Treatment – reflex syncope

• Avoid triggers

• Avoid dehydration

• Physical counterpressure manoeuvers – leg

crossing, hand grip – require prodromal

symptoms to be effective

• Tilt training

• Drugs – largely disappointing – midodrine,

fludrocortisone, beta blockers, paroxetine

• Pacing – may help – if asystolic pause >3s with symptoms or >6s without symptoms (ISSUE-3)

Therapy

Clinical studies based on Tilt Test

findings

Clinical studies based on Implantable

Loop Recorder findings

ISSUE-2

• Patients with three or more clinically severe syncopal episodes in the last

2 years without significant electrocardiographic and cardiac abnormalities were included

• One hundred and three patients had a documented episode and entered Phase II: 53 patients received specific therapy [47 a pacemaker because of asystole of a median 11.5 s duration and six anti-tachyarrhythmia therapy (catheter ablation: four, implantable defibrillator: one, anti-arrhythmic drug: one)] and the remaining 50 patients did not receive specific therapy

• The 1-year recurrence rate in 53 patients assigned to a specific therapy was 10% (burden 0.07±0.2 episodes per patient/year) compared with 41% (burden 0.83±1.57 episodes per patient/year) in the patients without

specific therapy (80% relative risk reduction for patients, P=0.002, and 92% for burden, P=0.002)

• The 1-year recurrence rate in patients with pacemakers was 5% (burden 0.05±0.15 episodes per patient/year) Severe trauma secondary to

syncope relapse occurred in 2% and mild trauma in 4% of the patients

Time to first recurrence of syncope according to the intention-to-treat analysis

Michele Brignole et al Circulation 2012;125:2566-2571

Copyright © American Heart Association, Inc All rights reserved

Clinical studies based on Implantable

Loop Recorder findings

Conclusion

• Syncope is very common!

• Good history and examination key

• Treatment dictated by structurally normal /abnormal heart / genetic disorders

• Medical therapy is possible but generally limited efficacy

• Role of pacemaker therapy limited for

vasovagal syncope