Brugada syndrome (BrS) is a rare inherited arrhythmia syndrome leading to an increased risk of sudden cardiac death, despite a structurally normal heart. Diagnosis is based on a specific electrocardiogram pattern, observed either spontaneously or during a sodium channel blocker test.
BrS is definitively diagnosed when a type I ST-segment elevation is observed either spontaneously or after intravenous administration of a sodium channel blocking agent (ajmaline, flecainide, pilsicainide, or procainamide) in at least one right precordial lead (V1 and V2), which are placed in a standard or a superior position (up to the 2nd intercostal space).
Expert Consensus Recommendations on Brugada Syndrome Diagnosis
- BrS is diagnosed in patients with ST-segment elevation with type 1 morphology ≥2 mm in ≥1 lead among the right precordial leads V1, V2, positioned in the 2nd, 3rd or 4th intercostal space occurring either spontaneously or after provocative drug test with intravenous administration of Class I antiarrhythmic drugs.
- BrS is diagnosed in patients with type 2 or type 3 ST-segment elevation in ≥1 lead among the right precordial leads V1, V2 positioned in the 2nd, 3rd or 4th intercostal space when a provocative drug test with intravenous administration of Class I antiarrhythmic drugs induces a type I ECG morphology.
This ECG pattern, previously known as a type 1 ECG, consists of a coved ST-segment elevation in one right precordial lead of >0.2 mV, ending with a negative T wave. Other ECG patterns are not sufficient for the diagnosis, but can suggest the need for a sodium channel blocker test to the physician, which can unmask a type 1 pattern. Ajmaline (1 mg/kg over 5–10 min), flecainide (2 mg/kg over 10 min) and procainamide can be used.
References:
- Gourraud JB, Barc J, Thollet A, Le Marec H, Probst V. Brugada syndrome: Diagnosis, risk stratification and management. Arch Cardiovasc Dis. 2017 Mar;110(3):188-195. [Medline]
- Priori SG, Wilde AA, Horie M, et al. HRS/EHRA/APHRS Expert consensus statement on the diagnosis and management of patients with inherited primary arrhythmia syndromes: Document endorsed by HRS, EHRA, and APHRS in May 2013 and by ACCF, AHA, PACES, and AEPC in June 2013. Heart Rhythm. 2013;10:1932–1963. [Medline]
- Wilde AA, Antzelevitch C, Borggrefe M, Brugada J, Brugada R, Brugada P, Corrado D, Hauer RN, Kass RS, Nademanee K, Priori SG, Towbin JA; Study Group on the Molecular Basis of Arrhythmias of the European Society of Cardiology. Proposed diagnostic criteria for the Brugada syndrome: consensus report. Circulation. 2002 Nov 5;106(19):2514-9. [Medline]
Created Oct 21, 2019.
