Relationship Between Heart Rate Variability And Arrhythmia In Elderly Type 2 Diabetic Patients With Coronary Heart Disease

Background and ObjectiveDiabetes mellitus has become one of the major non-infectious diseases affecting human health all over the world.The chronic complications can bring immeasurable mental and economic burdens to individuals,families and countries,which will seriously affect our economy and society continously.Diabetic cardiac autonomic neuropathy is one of the common and easily overlooked chronic complications of diabetes.Current research suggests that it is caused by damage of autonomic nerve fibers that regulate heart rate,cardiac output,cardiac contractility,cardiac electrophysiology,and vasoconstriction and dilation.,And it will lead to many heart diseases,including tachycardia and lethal arrhythmia,etc.In severe cases,it may endanger life,but it did not attract enough attention.Heart rate variability reflects the activity of the cardiac autonomic nervous system,and can quantitatively evaluate the sympathetic and vagal tone of the heart and its balance.It can be used to predict the condition and prognosis of cardiovascular disease and is considered as a valuable indicators that can predict sudden cardiac death and arrhythmia.The results of relevant studies show that heart rate variability is an important predictor of arrhythmia in type 2 diabetes,but there are few studies in our country.In this study,elderly patients with type 2 diabetes mellitus complicated with coronary heart disease were studied to investigate the relationship between the changes in heart rate variability and the incidence of arrhythmia,and the estimated value of the risk of arrhythmia.Study Object and Methods Study ObjectIn this study,105 elderly patients with coronary heart disease at the First Affiliated Hospital of Zhengzhou University from January 2017 to December 2017 were divided into CHD combined T2 DM group(diabetic group)54 cases and CHD uncombined T2 DM group(no diabetes group)according to the disease condition.In 51 patients,the diabetic group met the diagnostic criteria of type 2 diabetes and was diagnosed as coronary heart disease by coronary angiography.The average age was(68.6±7.5)years.There were 29 males and 25 females.The average age of the non-diabetic group was 72.5±6.5.Years old,26 males and 25 females.In the same period,42 healthy persons in our hospital were included in the control group.There were 20 males and 22 females with an average age of(67.1±4.4)years.There was no statistically significant difference in baseline data between the two groups in terms of age,gender,blood lipids,mean heart rate,and other diseases.All patients enrolled in the study had informed consent and signed informed consent.Study MethodsCollection includes demographic characteristics(age,gender),past history(whether diabetes mellitus,coronary heart disease);all subjects were fasted after admission,and triglyceride(TG),total cholesterol were measured using an automatic biochemical analyzer(TC),low-density lipoprotein cholesterol(LDL-C),and high-density lipoprotein cholesterol(HDL-C),all using the MAC5000 type 12-lead synchronous dynamic electrocardiogram produced by Marquette.DCG)and its own analysis system,continuous monitoring of 24 h ECG signal,recording time is greater than 23 h,through the man-machine dialogue to remove interference artifacts,automatically calculate the average heart rate and HRV time domain indicators:(1)The standard deviation(SDNN)of all sinus rhythm RR interval(NN interval)within 24 h;(2)The standard deviation(SDANN)of the mean value of normal cardiac cycle in 5 min section within 24 h.(3)The number of >50ms between adjacent NN intervals accounts for the percentage of total sinus atrial beats(PNN50);(4)Homogeneous root of adjacent normal cardiac cycle difference(rMSSD),and the use of dedicated personnel for analysis of heart rate variability and interpretation of a variety of arrhythmia types.Statistical methodsSPSS 17.0 software was used for statistical analysis.Measured data with normal distribution and homogeneity of variance were expressed.Analysis of variance was used and LSD test was used to compare the groups.The comparison of multiple sets of count data was expressed as a percentage and the χ2 test was used.ResultThe incidence rate of arrhythmia in diabetic group was higher than the control group,HRV and time domain parameter of SDNN,SDANN PNN50 is lower than the control group,the difference was statistically significant(P<0.05),but as for rMSSD,there was no significant difference between the two groups(P > 0.05).The incidence rate of arrhythmia in non-diabetic group was higher than control group,HRV and the time domain parameters of SDNN,PNN50 is lower than the control group(P <0.05),but as for SDANN,rMSSD,there was no significant difference between the two groups(P > 0.05).The incidence rate of arrhythmia in diabetic group was higher than that in non-diabetic group,HRV and the time domain parameters of SDANN was lower than that of non-diabetic group(P <0.05),but as for SDNN,rMSSD,PNN50,there was no significant difference between the two groups(P > 0.05).ConclusionThe HRV of elderly T2 DM with CHD patients is decreased obviously,especially for the the time domain parameters of SDANN,the incidence rate of arrhythmia is increased at the same time.HRV monitoring has a certain predictive value for the risk of arrhythmia in elderly patients with T2DM.