Analysis Of Heart Rate Variability And QT Dispersion In Elderly Hypertensive Left Ventricular Hypertrophy Patients

Background and objective：Left ventricular hypertrophy in essential hypertension complicated with primaryhypertension is the most important feature of the heart of one of the changes is to increasethe risk of cardiovascular complications, and mortality factors. Left ventricularhypertrophy as the internal mechanism of independent risk factors for EH patients withsudden death also needs further study. Heart rate variability (HRV) is the evaluation ofneural activity level of cardiac noninvasive index. The present research shows thatessential hypertension (EH) patients with left ventricular hypertrophy (LVH) andventricular arrhythmias, especially malignant ventricular arrhythmia appeared, studies havealso shown that with heart rate variability (HRV) decrease. Increased QT dispersion hashigh clinical value for the prediction of acute myocardial infarction in the malignantarrhythmia and sudden death and other aspects. Dynamic electrocardiogram and routinetwelve lead ECG data based on the analysis of primary hypertension with left ventricularhypertrophy, aims to investigate the relationship between hypertension patients with leftventricular involvement with HRV and QTd and its clinical significance.Methods:Using LoGIQT color Doppler ultrasound of American GE company’s heartbeatinstrument, the probe frequency of3.5-5MHz. M type ultrasonic continuous measuredthree heartbeat interventricular septal thickness end diastolic period (IVST), leftventricular posterior wall thickness (LVPWT) and left ventricular end diastolic diameter(LVIDD), and the average. According to Devereuxn, the formula to calculate the leftventricular mass (LVM):LVM (g)=0.832[(LVIDD+IVST+LVPWT)3-LVIDD3]+0.6.196patients with essential hypertension were divided into no left ventricular hypertrophygroup (group A,97cases) and left ventricular hypertrophy group (group B,99cases),through the observation on Dynamic ECG heart rate variability and QT dispersion in thetime domain index. Statistical analysis was performed using SPSS19.0software, P <0.05 was statistically significant.Results:①The time domain parameters of heart rate variability of SDNN, SDNNI, rMSSDhese parameters in group B is much larger than A group of data, statistical significance isvery obvious(P <0.05)②the time domain parameters of heart rate variability of pNN50,triangular index, these parameters in group B is much larger than the group Adata,statistical significance is very obvious (P <0.1);③the QT dispersion in QTd, theseparameters in group B is much larger than the A group data, statistical significance is veryobvious (P <0.05).Conclusion:1.Hypertension with left ventricular hypertrophy group, the SDNN, pNN50, rMSSDD,triangle index was significantly lower than that of no left ventricular hypertrophy group(P<0.05), the left ventricular hypertrophy group there was a serious sympathetic,parasympathetic tone imbalance, this agreement with results reported in the literature.2. Associated with left ventricular hypertrophy in patients with hypertension, the QTdincreased significantly. QTd not only can be used to evaluate the hypertension with leftventricular hypertrophy and dangerous l|risk index, also can be used as important indexesof left ventricular whether reversal of evaluation after treatment.