The Research Of Correlation Between Blood Pressure Variability And Left Atrial Diameter With The Patients Of Hypertension

Objective: Blood pressure measurement is the main method to evaluatethe blood pressure level, diagnose hypertension and observe theantihypertensive effects. At present, in our daily clinical practice, we mainlytake clinic blood pressure, dynamic blood pressure and home blood pressurethree ways. Recently, the ambulatory blood pressure monitoring (ABPM) iswidely used, and the research on blood pressure variability (BPV) more andmore. BPV is a dynamic and complex phenomenon including short-term andlong-term fluctuations as a result of intricate interactions among behavioral,environmental, humoral, and neural central or reflex influences, as well asother potential contributing factors. Measures of BPV can be obtained throughdifferent methods, i.e., continuous beat-to-beat BP recordings, conventionaloffice BP (OBP) measures,24-h ambulatory BP monitoring (ABPM) or homeBP monitoring (HBPM). BP fluctuations can be assessed over different timeintervals, i.e., in the very short term (beat-by-beat), in the Several minutes, inthe short term (over24h) and in the long term (day by day, between seasons orvisit to visit).The main pathological change of hypertension are arterial lesions andleft ventricular hypertrophy. Along with the progress of the disease, heart,brain, kidney and other important organs are involved, the structure andfunction are changed with different degree.2010China HypertensionPrevention Guide define the target organ damage for hypertension: Leftventricular hypertrophy or echocardiographic left ventricular mass indexincrease; Carotid ultrasound showing carotid intima-media thickness orthickening of the carotid artery atheromatous plaque; the speed of Neck-femoral artery pulse transmission increase quickly; Ankle/arm blood pressureindex down; eGFR reduced or serum creatinine moderately elevated; Microalbuminuria or albumin/creatinine ratio rising. Left ventricularhypertrophy is the symbol of change of high blood pressure target organdamage, and closely related to the blood pressure level. Recent study showthat: compared with the average blood pressure level, the relationship betweenBPV increase and left ventricular hypertrophy is more closely. It has beenreported that the emergence of left atrium enlargement is often earlier than theemergence of left ventricular hypertrophy in hypertension, left atriumenlargement is the early performance of hypertension heart damage. However,the study about the correlation between blood pressure variability and leftatrial diameter with the patients of hypertension is less. This research aims toexplore the relationship between BPV and left atrial diameter with the patientsof hypertension, So as to provide better guide for the diagnosis, treatment forhypertension, and to evaluate the risk of high blood pressure, to providereference for better prevent hypertension heart damage.Methods:80subjects were chosen from Cardiology Department of HebeiMedical University Second Hospital, including mail33, female47.They werepatients of first visiting, not regular treatment and discontinuation ofanti-hypertensive drugs used five half life. Hypertension diagnosis standardbasis is according to2010China Hypertension Prevention Guide. All subjectswere strictly in accordance with the entry and exclusion criteria. All subjectswere firstly recorded age, gender, height, weight，then we calculated Bodymass index(BMI), surface area, record hypertension course. In the quietcondition, we applicated desktop mercury sphygmomanometer measuringblood pressure once every5minutes, monitoring three times continuously,recording blood pressure, calculating the BPV，the means of SBP and themeans of DBP in15minutes. In the fasting state,3ml venous blood wereextracted, measuring glucose, cholesterol and creatinine. Using non-invasivediagnosis of dynamic blood pressure monitor for24-hour ambulatory bloodpressure monitoring,24hSBPV,24hDBPV, day SBPV, day DBPV, nocturnalSBPV, nocturnal DBPV, the mean of24h SBP, the mean of24h DBP wereanalyzed automatically. Echocardiography were checked to measure left atrial diameter index (LADI) on the basis of the body surface area.All the data conforming to the normality are presented as mean±standarddeviation. According to Recommendations of American Society ofEchocardiography’s Guidelines and the European Association ofEchocardiography, to LADI>2.3cm/m~2for high LADI group, to LADI≤2.3cm/m~2for normal LADI group, all data will be divided into two groups.The data conforming to the normality between two groups were comparedthrough t test, using multiple linear regression analysis analyses the influencefactors of LADI and the corresponding influence degree. P<0.05hassignificant statistical significance. In this study, SPSS16.0statistical softwarewas used to analyses statistics.Result: Data of high LADI group: age55.85±11.00, BMI30.19±2.14,hypertension course12.3±5.39, glucose5.37±0.74, cholesterol5.00±0.89,creatinine63.27±8.24,15minSBPV3.00±0.97,15minDBPV5.86±2.05,24hSBPV13.98±1.7,24hDBPV16.74±2.25, day SBPV10.22±3.27, dayDBPV13.08±2.45, nocturnal SBPV12.43±1.91, nocturnal DBPV16.58±3.08, the mean of15min SBP156.28±10.42，the mean of15min DBP100.74±9.53，the mean of24h SBP160.55±18.33, the mean of24h DBP108.24±12.3；normal LADI group: age51.74±11.07, BMI24.28±2.17, hypertensioncourse10.60±3.51, glucose5.13±0.82, cholesterol5.02±0.91, creatinine70.32±20.07,15minSBPV3.45±1.35,15minDBPV4.95±2.06,24hSBPV8.84±1.41,24hDBPV11.26±2.12, day SBPV9.76±2.89, day DBPV12.10±3.57, nocturnal SBPV7.21±1.85, nocturnal DBPV8.26±2.66, the meanof15min SBP152.65±8.46，the mean of15min DBP97.38±7.65，the meanof24h SBP150.45±15.68, the mean of24h DBP100.45±11.45. Amongabove data, age, hypertension course, glucose, cholesterol, creatinine,15minSBPV,15minDBPV, day SBPV, day DBPV, the mean of15min SBPand the mean of15min DBP were no significant difference between twogroups(P>0.05). However, data of high LADI group were larger than data ofnormal LADI group on BMI,24hSBPV,24hDBPV, nocturnal SBPV，nocturnal DBPV the mean of24h SBP and the mean of24h DBP (P<0.05).The multiple linear regression analysis indicate that the influencefactors of LADI were nocturnal SBPV,24hSBPV,24hDBPV, the mean of24hSBP, the mean of24h DBP and BMI, but not nocturnal DBPV. Thestandardized regression coefficient were in order of descending were nocturnalSBPV0.458(P=0.000),24hSBPV0.281(P=0.017),24hDBPV0.168(P=0.020),the mean of24h SBP0.160(P=0.030), the mean of24h DBP0.160(P=0.030),BMI0.089(P=0.013), nocturnal DBPV0.018(P=0.671).Conclusion:1Among above data, age, hypertension course, glucose, cholesterol,creatinine,15minSBPV,15minDBPV, day SBPV, day DBPV, the mean of15min SBP and the mean of15min DBP were no significant difference betweentwo groups(P>0.05). However, data of high LADI group were larger than dataof normal LADI group on BMI,24hSBPV,24hDBPV, nocturnal SBPV，nocturnal DBPV the mean of24h SBP and the mean of24h DBP (P<0.05).2Nocturnal SBPV,24hSBPV,24hDBPV, the mean of24h SBP, themean of24h DBP and BMI, are the influence factors of LADI, and nocturnalthe degree of SBPV influence is the largest.