Quantitatively Assessment Of Left Ventricular Myocardial Function By Velocity Vector Imaging In Uremic Patients With Different Quantity Of PTH

Backgroud:Most of uremic patients died of uremic cardiomyopathy. Recently we found secondary hyperparathyroidism is a important role. Scholars at home and abroad have found there were much more injury on myocardium of uremic patients with PTH more than 3 times of upper normal limnit.But the routine technique of ECHO could only estimate the global heart movement and could not evaluate effectively local myocardium movement damaged by different quantity of PTH.Recently developed new technique-Velocity Vector Imaging(VVI)can conquer the angle-dependency,the drag of surrounding myocardial and interference of the global heart movement and can estimate exactly regional myocardium function.No scholars at home and abroad had studied the the left ventricular longitudinal function in uremic patients with differnent quantity of PTH.Objective:To investigate the regional longitudinal contraction and relaxation of left ventricle in patients with differnent quantity of PTH,compared with normal persons,characterize the regularity of left ventricular longitudinal function;To characterize change sequence of systolic function and diastolic function in uremic patients with different quantity of PTH.To discuss the important clinical value of velocity vector imaging in quantitatively evaluating regional longitudinal function of left ventricle. Methods:60 patients diagnosed uremia were divided into 2 groups according to the value of PTH(1.48～7.63pmol/L):Group A is 30 patients with PTH less than 3 times of upper normal limit,Group B is 30 patients with PTH more than 3 times of upper normal limnit.Normal control group is 30 healthy people.They were matched with for sex and age.Exclusion criteria for all subjects were HBP,cardiac valve disease, congenital heart disease,Diabetes mellitus,thyroid disease,metabolic disease,connective tissue disease,dystrophy,severe dysfunction of liver and kidney,contact of toxic,alcohol abuse,pregnant woman in perinatal period.All people were evaluated by Velocity Vector Imaging. Get indexs below in 16 segments from 1 heart beat respectively to assess left ventricular longitudinal contraction and relaxation:Ⅰ-systolic max strain rate(SSRmax);Ⅱ-diastolic max strain rate(DSRmax);Ⅲ-peak time of strain rate(PTSR).Results:The SSRmax and DSRmax were not obvious different from the base to apex in normal group.PTSR had good coherence among 16 myocardium segments in normal group.Compared with normal group,in group A,SSRmax in base,medium and apex of posterior septum wall and superior wall,base and medium of anterior septum wall,apex of laternal and anterior wall,medium of posterior wall wall were significantly lower(P＜0.05);SSRmax in group B were significantly lower(P＜0.05 or 0.01).In all patients,all segments' DSRmax were significantly lower,PTSR were significantly longer(Group A p＜0.05, Group B p＜0.01).Compared with Group A,SSRmax in group B,apex of laternal wall,medium of anterior septum wall,posterior wall,medium and apex of posterior septum wall and superior wall,base,medium and apex of anterior wall were significantly lower(P＜0.05);In group B all segments' DSRmax were significantly lower,PTSR were significantly longer(P＜0.05).Conclusion:All segments' relaxation and coherence were obvious decrease,different segments' contraction were decrease in varing degree,proving the dysfunction of relaxation happen before contraction,and PTH injury not only the global heart movement,but aslo local myocardium movement.In addition,the higher the PTH,the much worse the local cardiomyopathy function.VVI is another viable objective tool to quantitatively assess LV segmental function damaged by different quantity of PTH.It proved that myocardium is damaged by PTH with varing degree.