Evaluation Of Right Ventricular Strain Values In Patients With Non-ischemic Dilated Cardiomyopathy By Cardiac Magnetic Resonance Tissue Tracing

Objective: To assess the feasibility of retrospective strain analysis of right ventricle in patients with non-ischemic dilated cardiomyopathy(NIDCM)by cardiac magnetic resonance feature tracing(CMR-FT).To investigate the potential mechanism of right ventricular dysfunction in NIDCM patients by the correlation analysis of right ventricular function parameters with left atrial volume,left atrial emptying fraction and left ventricular ejection fraction.Methods: A total of 58 patients diagnosed with NIDCM in our hospital and 30 healthy volunteers(control group)were retrospectively enrolled in this study underwent late gadolinium enhancement cardiac magnetic resonance(LGE-CMR)to compare biventricular function,left atrial function and right ventricular strain parameters of the two groups.Patients in the NIDCM group were divided into right ventricular dysfunction group(RVEF<45%)and right ventricular function preserved group(RVEF ≥ 45%)according to the results of right ventricular ejection fraction(RVEF).Compare the 3D strain parameters of right ventricular between right ventricular function preserved group and control group.Baseline characteristics,cardiac function parameters and the right ventricular 3D strain parameters of were compared between right ventricular dysfunction group and right ventricular function preserved group in NIDCM patients.Meanwhile,repeatability test of right ventricular strain parameters and Pearson correlation analysis between RVEF and left ventricular function were performed.Results: 1.Compared with the control group,the 3D global and regional strain of the right ventricle in patients with NIDCM were distinctly reduced(P < 0.001).Left ventricular ejection fraction(LVEF),RVEF and left atrial empty fraction(LAEF)in NIDCM group were lower than those in control group,while biventricular enddiastolic volume(EDV),biventricular end-systolic volume(ESV)and LA minimal volume(LA minimal volume(LAV min)were increased(P < 0.001).2.Compared with the control group,the RV’s global and regional longitudinal strain,middle and apical circumferential strain were decreased in NIDCM patients with right ventricular function preserved group(P < 0.001),but the global and regional radial strain,basal circumferential strain of right ventricle changed little.3.Left ventricular EDV,ESV and LAV min were larger in the right ventricular dysfunction group than in the right ventricular function preserved group,LVEF and LAEF were lower,and LGE(+)was more common in the interventricular septal wall(P < 0.001).4.The global and regional 3D strain parameters of RV in NIDCM patients with right ventricular dysfunction were lower than those in patients with right ventricular function preserved,especially for the longitudinal strain.5.RVEF was slightly positively correlated with LAEF and LVEF(LAEF R = 0.376,P = 0.004 vs.LVEF R = 0.412,P= 0.001).There was a slight negative correlation between RVEF and LA size(LAV min R =-0.401,P = 0.001).Conclusions: The strain analysis by using CMR-FT has good feasibility and repeatability.CMR-FT can quantitatively analyze right ventricular deformation and detect subclinical right ventricular dysfunction before RVEF declines significantly.Right ventricular dysfunction is primarily seen in patients with NIDCM with advanced heart failure and significant myocardial remodeling,with increased left atrial and left ventricular dilatation and dysfunction.