Application In Assessing Left Ventricular Structure And Function Of Patients With Essential Hypertension By 3.0T MRI

Objective To explore the application value in assessing left ventricular structure and function of patients with essential hypertension by 3.0T MRI.Materials Sixty patients with essential hypertension were studied by MRI,23 men and 37 women,aged 23-84 years,average age 51.62 years;by hypertensive grade divisied into 20 patients with mild and moderate hypertension,40 cases patients with severe hypertension; according to disease duration divisied into 32 cases of patients duration 5 years,14 cases of patients duration 5 years to 10 years,14 cases of patients duration＞10 years.Twenty patients were reviewed after about one year by rule treatment.Twenty cases of control group were studied, 10 men and 10 women,aged 25-70 years,the average age 49.85 years.Methods Magnetic resonance images were acquired with Philips 3.0 T superconductive magnetic resonance imager by balanced fast field echo / breath hold(b-FFE/BH) and sensitivity encoding(SENSE) technique.Left ventricular function,which include end-diastolic volume (EDV),end-systolic volume(ESV),ejection fraction(EF),stroke volume (SV),left ventricular mass(LVM),time-volume curve were automatically obtained by a commercially available software package for cardiac function analysis.EDV,ESV,SV and LVM had been considered by the body surface area(BSA) correction.Left ventricular mass index(LVMI) was calcuated based on LVMI =(LVM) /(BAS).Peak filling rate(PFR) and peak filling time(TPFR) were calculated based on time-volume curve.End-diastolic interventricular septum thickness(IVST),left ventricular end-diastolic posterior wall thickness(PWT) and left ventricular end-diastolic diameter(LVEDd) were measured in left ventricular long-axis and the relative wall thickness(RWT) was calculated according to RWT =(IVST + PWT) / LVEDd.Results①Left ventricular structure of 60 patients with essential hypertension was classified into normal left ventricular geometry in 10 cases,concentric remodeling in 6 cases,concentric hypertrophy in 34 cases and eccentric hypertrophy in 10 cases by MRI finding.Compared with normal control group,EF was increased in normal structure of group(P＜0.05) and SV was increased in concentric hypertrophy and eccentric hypertrophy group(P＜0.05).PFR was lower in concentric remodeling and concentric hypertrophy and eccentric hypertrophy(P＜0.05),TPFR extended in concentric hypertrophy and eccentric hypertrophy(P＜0.05).LVMI was significantly increased(P＜0.01) in concentric hypertrophy and eccentric hypertrophy.EDV was larger in group of concentric hypertrophy and eccentric hypertrophy than group of normal configuration(P＜0.05).EDV was increased in eccentric hypertrophy group compared to concentric remodeling group(P＜0.05). LVMI was significant statisticsly difference in group of concentric hypertrophy and eccentric hypertrophy compared with the rest of groups (P<0.05).②60 patients with hypertension grouped had been compared with the control group according to different hypertensive level.EF was higher in groups of mild and moderate hypertension than the control group(P<0.05).SV was increased in severe hypertensive group compared to the control group(P<0.05).PFR was lower and TPFR was extended compared to the control group(P<0.05).Inter-group comparison,EDV was significant statisticsly difference in severe group compared with mild and moderate group(P<0.05).③60 patients with hypertension grouped had been compared with the control group according to different course.EF and SV values were higher in the group of duration<5 years than the control group increased(P<0.05).PFR values was lower in groups of all course than those in the control group (P<0.05).TPFR value was extended in the group of duration<5 years and≥10 years compared to the control group(P<0.05).LVMI values was increased in the disease group compared to those in the control group (P<0.05).PFR value was lower in the group of duration≥10 years than the group of duration<5 years in the inter-group comparison(P<0.05).④20 patients with hypertension were reexamined after about one year treatment.Results showed that PFR and TPFR and LVM were significantly improved compared with pre-treatment(P<0.01).Conclusion①MRI can accurately evaluate left ventricular structure in the patients with hypertension.②Many datas of left ventricular systolic function is higher than normal in patients with hypertension,but the higher level of hypertension,longer duration,there may be reduction of left ventricular systolic function.③The damage of left ventricular diastolic function is more early and often than systolic function in patients with hypertension.The early left ventricular diastolic function anomaly can be definite by measurement to quantitative index of PFR and TPFR with MRI.④The research data shows a trend that damage of left ventricular function is concerned with hypertensive pressure higher level,longer duration and more severe damage in hypertensive patients.⑤MRI has high accuracy in evaluating left ventricular structure and function,it will be an effective method for evaluating prognosis and therapeutic effect of patients with essential hypertension.