Objective:To investigate the application of photoplethysmogram in analyzing the fingertip pulse amplitude volume (PAV)to evaluate the endothelial function in diagnosing coronary heart disease,and to clarify its relationship with the risk factors of cardiovascular diseases.Methods:Total 409 patients with chest pain accepted coronary angiography (CAG)were selected and diveded into positive group (CAG+)(n=288)and negative group (CAG-) (n = 121)according to angiographic results.Fingertip photoplethysmogram was used to analyze the fingertip PAV by the way of applying endothelial function diagnostic after reactive ischemia,and the relationship between the PAV value and the risk factors of coronary heart diseases was analyzed,and the critical reference value of prediction index of coronary heart disease was determined.The risk factors such as age,gender,serum total cholesterol (TC ), low density lipoprotein (LDL ), high density lipoprotein (HDL ), non-HDL, serum triglyceride (TG),hypertension,diabetes,smoking,family history of coronary heart disease,body mass index (BMI)of the subjects in various groups were analyzed,and the relationship between the risk factors of coronary heart disease and PAV was analyzed by Logistic regression analysis.Results:The PAV of patients in CAG+group was significantly lower than that in CAG-group (P <0.01).The peak point of PAV was<1.37,if PAV<1.37 was used to predict the coronary heart disease,the predictive sensitivity,the specificity,the positive prediction and the negative prediction were 74.65%,44.63%, 76.24%, and 42.52%.The Logistic regression analysis showed that PAV was negatively associated with hypertension,smoking history,TG (OR= 1.476,OR=2.002, OR = 1.844;P < 0.01 ). Conclusion: PAV is associated with coronary heart disease and its risk factors (hypertension,smoking history,TG),and PAV=1.37 can be used as the peak point to predict the coronary heart disease.