Eric Prystowsky, MD Director Clinical Electrophysiology Laboratory St Vincent Hospital Indianapolis,...
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Eric Prystowsky, MD Director Clinical Electrophysiology Laboratory St Vincent Hospital Indianapolis, IN Josep Brugada, MD Director Arrhythmia Unit, Cardiovascular Institute Hospital Clinic, University of Barcelona Barcelona, Spain The EP show: Brugada Syndrome
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Transcript of Eric Prystowsky, MD Director Clinical Electrophysiology Laboratory St Vincent Hospital Indianapolis,...
Eric Prystowsky, MDDirectorClinical Electrophysiology LaboratorySt Vincent HospitalIndianapolis, IN
Josep Brugada, MD Director Arrhythmia Unit, Cardiovascular Institute
Hospital Clinic, University of BarcelonaBarcelona, Spain
The EP show:Brugada Syndrome
A clinical and electrocardiographic syndrome
- no demonstrable structural heart disease
- suffering from cardiac arrhythmias
- a very specific ECG apparent RBBB ST elevation in leads V1-V3
Description of the syndrome
Brugada syndrome
The disease is associated with a mutation in sodium channel (SCN5A).
The early theory was that the syndrome reflected an increase in the Ito channel (governing the potassium current in phase 1 of the ECG).
In fact, the Ito current is only increased relative to the sodium current, because the sodium channel closes prematurely.
J Brugada
Ionic basis of disease
Brugada syndrome
ECG definition has become more and more strict.
ST elevation of a coved type of at least 2 mm or ST elevation of saddleback type if it becomes coved type under stress with anti-arrhythmics.
Elevation is always present in V2, and either V1 or V3 (usually both).
J Brugada
Diagnosing the syndrome
Brugada syndrome
Flecainide used now that ajmaline is no longer available.
Given in an IV in Europe, but maybe 200mg orally but patient must be monitored for 8 hours because of the long half-life.
Procainamide is effective in unmasking the syndrome, but the ECGs are much less spectacular. May have less specificity and sensitivity than ajmaline.
J Brugada
Drugs for diagnosis
Brugada syndrome
In all patients where we had genetic confirmation of the disease, we did not have a single false negative or false positive with ajmaline.
The ajmaline test was consistently reproducible in over 100 patients.
Patients’ hearts are different and the positioning of the leads can play an important role in diagnosis since the syndrome is localized in a specific region of the heart.
J Brugada
Sensitivity and specificity
Brugada syndrome
EP testing
Brugada syndrome
Every single patient that has a classic Brugada ECG gets an EP test.
Asymptomatic patients who have a normal basal ECG have 0% events in follow-up so far.
So we don’t do EP tests in these patients.
Wait and watch because there is no evidence they are at risk.
J Brugada
Asymptomatics
Brugada syndrome
If the base ECG is abnormal, then we follow with EP testing.
In these patients, 2/3 are non-inducible.
If non-inducible, we do nothing, because the event rate is extremely low.
Events in asymptomatic patients with abnormal basal ECG occurred in patients who were inducible by EP testing.
J Brugada
Patient with a father who died of sudden death – no ECG available.
The patient has abnormal ECG, which becomes classic Brugada after stressing with flecainide.
This patient should get EP study due to family history.
If the study is positive, give them a defibrillator. If negative, do nothing.
J Brugada
Clinical decision making
Brugada syndrome
Only 60% of sudden deaths in families with known Brugada syndrome can be attributed to the syndrome.
ECGs can normalize over time. A completely normal ECG in one moment doesn’t mean it will always be normal.
If the ECG ever becomes abnormal, you then follow up with drug tests and then EP testing.
J Brugada
Clinical decision making
Brugada syndrome
A 28 year old uncle who died suddenly, no ECG available. My father died suddenly at 46. No autopsy.
The kid has a classic Brugada ECG but is non-inducible to EP testing.
I would suggest a defibrillator due to the strong family history, but there is no evidence that the risk is extremely high.
But with the strong family history and the baseline Brugada ECG, I would be nervous.
J Brugada
Clinical decision making
Brugada syndrome
Definition of Brugada ECG: RBBB in V1-V3 (V2 most important) Coved ST-segment elevation of > 2mm
If not present at baseline, ECG can be induced by flecainide or procainamide.
ICD is treatment of choice for patients with documented cases of serious arrhythmias
In general if the EP study shows no inducible VT, watch and wait.
Review
Brugada syndrome
Brugada syndrome
