Electrocardiographic characteristics of the short QT syndrome

(A) A 12-lead ECG showing ECG characteristic of SQT1.
(B) A 12-lead ECG showing ECG characteristic of SQT4 displaying combined ECG phenotype of Brugada and short QT syndromes. Note that ECG shows Brugada type ST elevation in V1 and V2 after administration of ajmaline in addition to short QT intervals.