The panels display leads V1 to V3 (25 mm/ssecond, 1 cm/mV) acquired at baseline ("pre-test") and up to the 4th minute during intravenous administration of the sodium-channel blocker ajmaline in a 15-year-old female patient with suspected Brugada syndrome and a nondiagnostic baseline ECG. A type 1 Brugada pattern ECG is unmasked, which is important for prognosis and risk stratification purposes.
