The Brugada algorithm exploits fundamental differences in ventricular activation between VT and SVT with aberrancy. In SVT with aberrant conduction, the impulse originates in the atria or AV node and depolarizes the ventricles via the normal His-Purkinje network—just with a bundle branch block. This results in relatively rapid ventricular activation (narrower QRS, shorter RS interval) and typical bundle branch block morphologies. In VT, the impulse originates in the ventricular myocardium and spreads cell-to-cell (myocyte-to-myocyte) outside the Purkinje system. This produces slower activation (wider QRS, longer RS interval), aberrant vectors (precordial concordance, extreme axis), and independent atrial and ventricular activity (AV dissociation).

Some experts add the Vereckei aVR criterion as an "or" to Step 4. Vereckei (2008) proposed a 4-step algorithm using only lead aVR. The most useful sign: a dominant initial R wave in aVR (the QRS begins with an R wave) is highly specific for VT. This is because aVR looks at the heart from the right shoulder; a positive initial deflection implies the VT is originating in the left ventricle with a rightward/superior axis. This can help when precordial leads are ambiguous.

A simpler alternative to the full Brugada algorithm is the "Ultrasimple Brugada" or RWPT criterion: Measure the time from the onset of the QRS to the peak of the R wave in leads V1-V2. An RWPT ≥50 ms in V1 or V2 suggests VT. This is easier to measure than the RS interval and has similar specificity (90-95%). Sensitive for VT but may be negative in fascicular VT (which has narrower QRS).

The Brugada brothers (Pedro, Josep, and Ramon) are renowned Belgian and Spanish cardiologists. Pedro Brugada (born 1952, Barcelona) and Josep Brugada (born 1958) were working at the Cardiovascular Center, OLV Hospital in Aalst, Belgium, and the University of Limburg in Maastricht, the Netherlands, when they developed the algorithm in 1990-1991. They noted that existing criteria (Wellens, 1978; Kindwall, 1988) had poor specificity and were frequently discordant, leading to diagnostic errors. They hypothesized that the intrinsic deflection (RS interval) would be prolonged in VT regardless of QRS morphology. Their 1991 Circulation paper validated the algorithm prospectively in 554 patients with electrophysiologically proven arrhythmias. The algorithm was named after them, though separately they are also known for describing Brugada syndrome (a genetic arrhythmia syndrome characterized by ST elevation in V1-V3 and sudden cardiac death, first described in 1992—one year after the algorithm was published).

The Brugada algorithm remains the most widely taught and clinically used approach to wide-complex tachycardia differential diagnosis more than 30 years after its publication. No subsequent algorithm (Vereckei, Pava, or others) has consistently outperformed it in head-to-head comparisons. The algorithm is included in all major emergency medicine, cardiology, and critical care textbooks and is recommended by the ACC/AHA/HRS guidelines (2017). Its primary limitations—poor sensitivity for fascicular VT and poor specificity for antidromic AVRT—are well described, and clinicians are taught to recognize these exceptions. The "default to VT when uncertain" rule, based on the algorithm's 80% VT prevalence data, has likely prevented thousands of deaths from inappropriate verapamil administration. Pedro Brugada passed away in 2022; his legacy includes both the Brugada algorithm and Brugada syndrome.