Elimination of fatal arrhythmias through ablation of triggering premature ventricular contraction in type 3 long QT syndrome.

Congenital long QT syndrome (LQTS) is the most common inherited arrhythmia, fatal arrhythmias are the main causes of sudden death, and often induced by the premature ventricular contractions (PVCs). Ablation of the triggering PVCs may eliminate the fatal arrhythmias and prevent the sudden death in patients with LQTS. We report a 19-year-old boy diagnosed with type 3 LQTS, frequent fatal arrhythmias induced by PVCs with the identical QRS morphology.

LQTS gene LOVD database.

The Long QT Syndrome (LQTS) is a group of genetically heterogeneous disorders that predisposes young individuals to ventricular arrhythmias and sudden death. LQTS is mainly caused by mutations in genes encoding subunits of cardiac ion channels (KCNQ1, KCNH2,SCN5A, KCNE1, and KCNE2). Many other genes involved in LQTS have been described recently(KCNJ2, AKAP9, ANK2, CACNA1C, SCNA4B, SNTA1, and CAV3).

Single nucleotide polymorphisms and haplotype of four genes encoding cardiac ion channels in Chinese and their association with arrhythmia.

Background: Many studies revealed that variations in cardiac ion channels would cause cardiac arrhythmias or act as genetic risk factors. We hypothesized that specific single nucleotide polymorphisms in cardiac ion channels were associated with cardiac rhythm disturbance in the Chinese population.

Method: We analyzed 160 nonfamilial cardiac arrhythmia patients and 176 healthy individuals from which 81 individuals were selected for association study, and a total of 19 previously reported SNPs in four cardiac ion channel genes (KCNQ1, KCNH2, SCN5A, KCNE1) were genotyped.