The EP show: Brugada Syndrome Eric Prystowsky, MD Director Clinical Electrophysiology Laboratory St Vincent Hospital Indianapolis, IN Josep Brugada, MD Arrhythmia Unit, Cardiovascular Institute Hospital Clinic, University of Barcelona Barcelona, Spain

Description of the syndrome Brugada syndrome Description of the 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

Brugada syndrome Ionic basis of disease 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

Diagnosing the syndrome Brugada syndrome Diagnosing the 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

Brugada syndrome Drugs for diagnosis 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

Sensitivity and specificity Brugada syndrome Sensitivity and specificity 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

Brugada syndrome EP testing 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

Brugada syndrome Asymptomatics 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

Clinical decision making Brugada syndrome Clinical decision making 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 Clinical decision making 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 Clinical decision making 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

Review Definition of Brugada ECG: RBBB in V1-V3 (V2 most important) Brugada syndrome Review 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.

Brugada syndrome