Evaluation Of Subclinical Left Ventricular Dysfunction With Velocity Vector Imaging In Patients With Systemic Lupus Erythematosus (SLE)

Background:Systemic lupus erythematosus(SLE) is an autoimmune disease which is characterized by auto-antibodies formation and immune complex deposit.SLE can affect almost every organ and system,among which heart is an important target organ.SLE involves pericardium,conduct system of heart,myocardium,endocardium,valves, coronary arteries,et al,which is a common cause of death second only infection and renal failure.Autopsy researches indicated that 40-100% SLE patients had cardiac involvement,whereas most patients had no typical clinical symptoms of cardiac impairment,and this made it difficult to evaluate cardiac function in SLE patients.Velocity vector imaging(VVI) is a new technique which can quantitatively assess global and regional myocardial systolic and diastolic function.This study is aim to assess subclinical left ventricular function in SLE patients using VVI.Objective To assess subclinical left ventricular(LV) longitudinal systolic and diastolic function of each segment in SLE patients with VVI, and observe early changes of LV longitudinal function in comparison with healthy subjects.To investigate value of VVI in evaluating of subclinical LV dysfunction in SLE patients at early stage.Methods 30 in-patients and out-patients with SLE who visited our hospital from 2006 to 2007,all the patients were diagnosed SLE according to the diagnostic criteria formulated by U.S.Rheumatic Association in 1982.All patients had history inquisition,physical examination,X-ray,echocardiogram(ECG),and echocardiography tests. 30 healthy subjects were enrolled who were matched with SLE patients in terms of sex and age.The enrolled 30 SLE patients had no clinical symptoms of cardiac impairment or/and history of cardiac diseases,with normal pericardium,systolic and diastolic diameter of LV,left ventricular ejection fraction(LVEF)＞50%.Patients who had history of coronary artery disease,hypertension,congenital heart disease,diabetes mellitus, other connective tissue disease,or had severe lung,liver,renal,neural, hematological,psychiatry disease,and had arrhythmia(atrial fibrillation, atrial flutter,complete bundle-branch block) were excluded.Dynamic digital imagings of heart were collected and LV longitudinal segmental myocardial velocity(Vmax) in systolic period,strain(Smax) in systolic and early diastolic period,strain rate(SRmax) in systolic,early and late diastolic period were analyzed using VVI off-line software.Time to peak velocity,strain and strain rate of each segment were obtained at the same time.Every parameter was measured 3 time and average value was obtained.Results LV longitudinal myocardial velocity gradually decreased from basal,middle to apical segment in control group,whereas strain and strain rate had no significant differences.Time to velocity,strain and strain rate had good consistency in 16 segments.LV myocardial velocity, strain and strain rate had similar decreasing tendency from basal,middle to apical segment in SLE group who had normal LV global function,but each parameter was smaller than those in control group(P＜0.01) without statistically significance(P＞0.05)Conclusions LV longitudinal myocardial segmental velocity, strain and strain rate in both systolic and diastolic period had decreasing tendency from basal,middle to apical segment in SLE group with normal LV global function,which was similar with control group,but each parameter was smaller than those in control group(P＜0.01).This indicated that LV longitudinal myocardial dysfunction existed in each segment.In another word,each segment had both systolic and diastolic dysfunction,which was coincident with histopathologic test.VVI was more sensitive to detect cardiac impairment in SLE patients at early stage than conventional technique.VVI could objectively and quantitatively assess subclinical LV longitudinal dysfunction in SLE patients.