Characteristics Of Resting Heart Rate And Heart Rate Variability In Patients With H-type Hypertension

Objective: To analyze the relationship between resting heart rate and heart rate variability and plasma homocysteine in patients with hypertension,and to explore the characteristics of resting heart rate and heart rate variability in patients with H-type hypertension.Methods: 141 patients who underwent cardiovascular medicine in our hospital from January 01,2017 to December 31,2017 were selected,with an average age of62.0±13.2 years.All patients had a history of newly diagnosed hypertension or had a clear history of hypertension,but at least take no anti-hypertensive drugs for 1 week.The diagnostic criteria for hypertension are in line with the “Guidelines for the Management of National Grassroots Hypertension Prevention and Control” issued in2017,that is,under the premise of not taking anti-hypertensive drugs,the blood pressure is measured 3 times in the clinic on the same day,and the systolic blood pressure is≥140 mm Hg(1mm Hg = 0.1333 k Pa)and or diastolic blood pressure ≥ 90 mm Hg;if the patient has previously diagnosed hypertension,even if the blood pressure level is systolic blood pressure <140 mm Hg and/or diastolic blood pressure <90 mm Hg,it is directly diagnosed as hypertension.Exclusion criteria: there is a clear cause of secondary hypertension or laboratory blood pressure more than 160/100 mm Hg;non-sinus rhythm or severe sinus arrhythmia;liver function is significantly increased(visual jaundice or transaminase ≥ 2 times normal);previous history of heart failure or renal insufficiency;previous history of malignant tumors;significant fever in the past3 days(body temperature ≥ 37.3 ℃);nearly 1 week using digitalis preparations,B vitamins and other drugs that may affect heart rate and HRV.The blood Hcy concentration of 141 patients was determined by enzyme circulation method.According to the criteria of "H-type hypertension diagnosis and treatment expert consensus",the selected patients were divided into H-type hypertension group and non-H-type hypertension group.The H-type hypertension group was recorded as group A(Hcy < 10μmol/L,20 patients);the H-type hypertension group was divided into two groups according to the plasma Hcy concentration,that group B(10 μmol/L ≤ Hcy < 15 μmol/L,69 patients)and C group(Hcy ≥ 15μmol / L,52 patients).The fasting plasma glucose,total cholesterol,triglyceride,high-density lipoprotein and low-density lipoprotein concentrations of each patient were collected,and the 12-lead conventional electrocardiogram and 24-hour ambulatory electrocardiogram were completed to collect the resting heart rate and the time domain index of HRV,such as SDNN,SDNN-Index,RMSSD,PNN50 and frequency domain indicators HF,LF.Result:1.There was no significant difference in resting heart rate,SDNN,SDNN-Index,PNN50,HF and LF between group A and group B(P?0.05),while the measurements above were statistically different between group C and group A,group C and B(P<0.05).There was no significant difference in RMSSD among the three groups(P ?0.05).2.Among the three groups,4 patients in group A had a heart rate greater than 75beats/min,accounting for 10.0%.13 patients in group B,accounting for 18.8%.,27 patients in group C,accounting for 51.9%.There were 44 patients in all patients whose heart rate was more than 75 beats/min,accounting for 31.2%.3.Correlation between plasma Hcy concentration and resting heart rate and heart rate variability was analyzed by Pearson product moment.The results showed that there was a positive correlation between Hcy concentration and resting heart rate and systolic blood pressure(r = 0.245,0.497,P<0.05),and there was a negative correlation between Hcy concentration and SDNN,SDNN-Index,RMSSD,PNN50,HF,LF(r =-0.303,-0.243,-0.179,-0.239,-0.217,-0.208,P<0.05).Conclusion:1.In H-type hypertensive patients,Hcy concentration was positively correlated with resting heart rate,but negatively correlated with SDNN,SDNN-Index,RMSSD,PNN50,HF and LF.The higher the Hcy concentration,the higher the resting heart rate and systolic blood pressure,and the lower the SDNN,SDNN-Index,RMSSD,PNN50,HF and LF,and this change is more obvious when the Hcy is above 15μmol/L.2.Compared with non-H type hypertensive patients,the resting heart rate of patients with H-type hypertension is more obvious,while the HRV time domain indicators SDNN,SDNN-Index,PNN50 and frequency domain indicators HF,LF decrease more obvious,but the decrease of RMSSD is not obvious.