Correlation Research Between Primary Bundle Branch Block And SPG7 Gene

Background:Primary bundle branch block is more common in clinical practice.It can occur in both left and right bundle branches,and most of it occurs in patients without organic heart disease.Less is known about its etiology.Recent studies have shown tha t most of the pathogenic genes of bundle branch block in neurological diseases are loc ated in mitochondrial genes,so in-depth study on mitochondrial genes is helpful to un derstand the pathophysiological mechanism of primary bundle branch block.Objectives:This study collected 140 cases of patients with primary bundle branch blo ck,collected their clinical data through the electronic medical record system,Exon se cond-generation sequencing was performed on the mitochondrial gene-spastic paraple gia-7 gene(SPG7)to determine the correlation of SPG7 in primary bundle branch bl ock,and the correlation between gene variation and prognosis was determined by fol low-up.Methods: We continuously selected 140 patients with bundle branch block who in first affiliated hospital of Dalian medical university on January 1,2018 and Augu st 31,2019,including 15 patients with left bundle branch block and 125 patients wit h right bundle branch block.Clinical,biochemical and examination data of patients we re collected,and exon second-generation sequencing was performed on the SPG7 gen e.Patients were followed up for an average of 25 months.To analyze the variation of S PG7 gene in primary conduction system disease of heart and its correlation with progn osis.Results: A total of 140 patients with bundle branch block were collected in this study,including 15 patients with left bundle branch block and 125 patients with right bundle branch block.The mean age was 68.7±12.0 years old,with a male to female ratio of 94:46.SPG7 exon sequencing was performed in 140 patients,and it was found that 10 patients had SPG7 mutation,and the mutation rate is 7.14%.All patients were right bundle branch block.By comparing the baseline data of mutation carriers and mutation non-carriers,it was found that the right ventricular diameter of SPG7 gene carriers was significantly larger than that of non-carriers(19.8±2.5mm VS 18.2±2.3mm,P=0.035).A 28-month follow-up of 140 patients showed a significant increase in RV diameter(19.8±2.5mm VS 22.7±1.2mm,P=0.038)compared with baseline in patients with SPG7 mutation,but no significant change in RV diameter in non-carriers(18.2±2.4mm VS 18.2±2.6mm,P=0.983).Conclusion: 1.The mutation rate of SPG7 gene in bundle branch block is about 7.14%,and its further research needs large samples.2.SPG7 gene is associated with right ventricular remodeling in patients with right bundle branch block,and its pathophysiological mechanism requires further studies.