Expressions And Significance Of SCN5A And ANK2in Atrial Myocardium Of Patients With Unexplained Sudden Cardiac Death

Objective:To observe the protein expressions of SCN5A and ANK2in right atrial muscle cells of patients with unexplained sudden cariac death and evaluate their significance in forensic medicine.Methods:Fifty-eight autopsy hearts speciments were collected from Qingdao autopsy appraisal center from2011to2013. According to the cause of death and the result of HE staining results of corresponding parts, the whole speciments were divided into three groups(Group A, Group B and Group C). As the control group, Group A consists of20cases, which was made up of liver rupture(6cases)、traffic accident(8cases)、hanging (4cases) and spleen rupture(2cases). Group B was the sudden cardiac death died of the organic heart disease, which consists of20cases made up of sudden coronary death(13cases)、viral myocarditis (3cases)、 dilated cardiomyopathy(4cases). Group C was the18cases of unexplained sudden death..Immunohistochemical staining was used to detect the SCN5A and ANK2expression in right atrium cells. The Image-Pro Plus softaware was used for image processing.SPSS17.0was used for statistical treatment.Results:Myocardial fiber fracture in part of the myocardial specimens was observed in Group A. In Group B, myocardial specimens of SCD caused by coronary heart disease have atherosclerosis of the anterior descending coronary artery、left handed and right coronary artery in different levels; myocardial interstitial hyperplasia, edema and inflammatory cells infiltration can be seen in the sudden death of viral myocarditis; different degree of hypertrophy and atrophy can be seen in sudden death of dilated cardiomyopathy. No obvious anomalies were found in Group C. Immunohistochemical results shows that the positive expression of SCN5A can be seen in right atrial muscle cells of Group A, whose expression has no difference with Group B (t=0.318,P>0.05).The expression of Group A and Group B was higher than Group C (t=3.484,3.561, all P<0.01). The positive expression of ANK2can be seen in right atrial muscle cells of Group A, whose expression has no statistically significant difference with Group B t=0.223P>0.05). The difference between the expression of Group A and Group B to Group C has statistically significant difference (t=2.8782.519, P<0.01, P<0.05).Rank correlation analysis results show that the expression of SCN5A and ANK2in three groups in right atrial cells has no obvious correlation(r=0.324,-0.014,-0.159, P>0.05).Conclusion:The expressions of SCN5A and ANK2are changed in right atrial cells of unexplained sudden cariac death, which suggested they were corrected with SCD. No evidence to prove the expression of SCN5A and ANK2has obviously correlation with right atrial cells in unexplained sudden cariac death.