Antzelevitch et al. (2007) reported 2 probands with Brugada syndrome who also had shortened QT intervals on ECG. One was a 41-year-old man of Turkish descent who presented with atrial fibrillation and a QTc of 346 ms. Ajmaline ... Antzelevitch et al. (2007) reported 2 probands with Brugada syndrome who also had shortened QT intervals on ECG. One was a 41-year-old man of Turkish descent who presented with atrial fibrillation and a QTc of 346 ms. Ajmaline administration led to further elevation of the ST segments in leads V1 to V2, and monomorphic ventricular tachycardia was inducible. The patient had a brother who died of cardiac arrest at 45 years of age, and 2 daughters with QTc intervals of 360 and 373 ms, respectively. The other proband was a 44-year-old man of European descent who had prominent ST segment elevation in V1, saddleback ST segment elevation in V2, a prominent J wave in lead III, and a QTc of 360 ms; he was also recently diagnosed with facioscapulohumeral muscular dystrophy (see 158900). His mother had 2 syncopal episodes at age 48 that resulted in sudden cardiac death; his father, 2 sibs, and 3 children declined examination but reportedly did not exhibit the Brugada phenotype.
In 2 probands who had Brugada syndrome and shortened QT intervals on ECG, who were negative for mutation in genes known to be associated with the Brugada and short QT (see SQT1; 609620) syndromes, Antzelevitch et al. (2007) ... In 2 probands who had Brugada syndrome and shortened QT intervals on ECG, who were negative for mutation in genes known to be associated with the Brugada and short QT (see SQT1; 609620) syndromes, Antzelevitch et al. (2007) identified heterozygosity for mutation in the CACNA1C gene, G490R (114205.0003) and A39V (114205.0004), respectively. The 2 daughters of the Turkish proband with the G490R mutation also carried the mutation; the daughter with the longer QTc (373 ms) also had a known K897T polymorphism in the KCNH2 gene (152427).