Abstract: Objective To explore relationship between increase of fibrous and fatty in atrioventricular node（AVN） and narrowing of the AVN artery. To analyze the cause of pathological fibrosis and fatty infiltration in AVN. Methods One hundred and nineteen cases of sudden cardiac death determined by autopsy were selected and the histological sections were examined with Image-pro plus software to calculate the AVN area, AVN artery inside-diameter, AVN artery lumen area（LA） , AVN artery perimeter area（PA）, fibrous area and fatty area. All cases were divided into two groups： narrowing of artery group and normal control group. The changes of the PA/LA value and the fibrous and fatty contents were evaluated. Results The PA/LA value is the highest in 21-40 age group. The difference of the fatty contents and total interstitial tissue was statistical significance in the two groups under 40 years of age. Conclusion There is some relationship between the narrowing of the AVN artery and the increase of interstitial contents in AVN.

Key words: forensic pathology, atrioventricular node, stromal cells, narrowing of the artery