Background: Progressive left bundle branch block (LBBB) is a hereditary arrhythmia characterized by progressive conduction disturbances in the His-Purkinje system. LBBB has been linked to genes such as SCN5A that influence cardiac excitability but not to genes that influence cell-to-cell communication. Our goal was to explore whether nucleotide substitutions in genes coding SCN5A for cardiac channels would associate with LBBB.
Material and Methods: A family examination was performed in 96 patients with primary left bundle branch block (LBBB). The control group consisted of 411 patients without clinical ECG manifestations of cardiac diseases. All the examinees have undergone ECG, echocardioscopy, electrophysiological examination of the heart.
Results: by results of research it is established that the frequency of carriers of a heterozygous genotype (AG) among patients with LBBB (50%±5,1) was higher in comparison with control selection (34,8%±2,3). The obvious tendency to decrease in carriers of a homozygous genotype on extended allel (AA) among patients with LBBB (50%±5,1) in comparison with group of control (61,6%±2,4) is also noted.
Conclusions: In this work we for the first time revealed on clinical - genetic material association between hereditary disturbances of cardiac conduction, such as LBBB and rs1805124 polymorphism of SCN5A gene.