Right Ventricular Myocardial Mechanics Using Two-dimensional And Three-dimensional Speckle Tracking Echocardiography In End-stage Heart Failure Patients And It’s Correlation With Myocardial Fibrosis

Part1 Evaluation of Right Ventricular Myocardial Mechanics by2D-and 3D-STE in Patients With End-Stage Heart FailureObjective: We aimed to assess right ventricular myocardial mechanics by 2D-and3D-STE in patients with end-stage heart failure.Methods: We enrolled 105 patients with end-stage heart failure requiring heart transplantation.50 normal subjects matched with age and sex were selected as control groups.These patients were divided into two subgroups according to the results of coronary artery angiography: ischaemic cardiomyopathies(ICM,n=23,right coronary artery RCA stenosis≥50% with or without the remaining two main artery stenosis)and non-ischaemic cardiomyopathies subgroups(NICM,n=82,normal findings of coronary artery angiography).Right ventricular end-diastolic volume(RVEDV),RV end-systolic volume(RVESV),RV stroke volume(SV),RV ejection fraction(EF),RV free wall longitudinal strain(RVLS-fre),and RV septal wall LS(RVLS-sep)were measured by 3D-STE.RVLS-fre and RVLS-sep were also determined by 2D-STE.The conventional RV function parameters(fractional area change [FAC],tricuspid annular plane systolic excursion [TAPSE],myocardial performance index [MPI],tricuspid annulus systolic velocities [Tricuspid s’ ])were obtained.We compared these parameters between patients and normal subjects.RVLS obtained by 3D-and2D-STE were compared between ICM and NICM.Results:(1)Compared with controls,patients had higher RVEDV,RVESV and MPI(P<0.001),and lower RVLS-fre,RVLS-spe,RVEF,RVSV,FAC,TAPSE,Tricuspid s’,tricuspid e’,tricuspid a’ and tricuspid e’/a’(P<0.001).(2)In 105 patients,3D-STE –based RVLS-fre was lower than 2D-STE-derived RVLS-fre(-11.43±3.83% VS-12.30±3.95%;P=0.003),whereas 3D-STE–determined RVLS-sep was not different from 2D-STE-based RVLS-sep(-7.02±2.80% VS-7.43±3.98%;P=0.21).(3)Patients with non-ischaemic cardiomyopathies had significant lower 3D-RVLS-fre(-10.68±3.55% VS-14.06±3.70%;P<0.001)and 3D-RVLS-sep(-6.68±2.76% VS-8.26±2.64%;P=0.006)than those in patients with ischaemic cardiomyopathies.There was no difference in 2D-STE values between the two subgroups.Conclusions: End-stage heart failure patients present the lower RVLS values.There is significant difference in RVLS values between 3D-and 2D-STE.3D-STE is superior to 2D-STE for RV systolic function assessment in end-stage heart failure patients with different pathologies.PART2 Assessment of Right Ventricular Myocardial Fibrosis Using Two-dimensional and Three-dimensional Speckle Tracking Echocardiography in Patients with End-Stage Heart FailurePurpose:We aimed to identify which right ventricular longitudinal strain(RVLS)assessed by 2D-and 3D-STE is the most reliable parameter to predict RV myocardial fibrosis(MF)in patients with end-stage heart failure.Methods: 105 consecutive patients with end-stage heart failure undergoing heart transplantation were enrolled in our study.The conventional RV function parameters(RVEF,RVFAC,TAPSE,and Tricuspid s’),2D-and 3D-RVLS-fre were obtained in these patients.The degree of MF was quantified by using Masson trichrome stain in RV myocardial samples.The study population was divided into 3 groups according to the degree of MF on histology(mild,moderate,and severe MF).Results:(1)Patients with severe MF had lower 3D-RVLS-fre,2D-RVLS-fre and conventional parameters of RV function compared with those with mild and moderate MF.(2)RV MF strongly correlated with 3D-RVLS-fre(r =0.73;P < 0.001),modestly with2D-RVLS-fre(r =0.53;P< 0.001),weakly with conventional RV function parameters(r =-049~-0.29;P < 0.01).3D-RVLS-fre correlated best with the degree of MF(r =0.73 vs 0.29~0.53;P<0.05)compared with 2D-RVLS-fre and conventional parameters.(3)The model using 3D-RVLS-fre(R2=0.63;P < 0.001)was found to predict the degree of MF more accurate than the 2D-RVLS-fre(R2=0.52;P< 0.001).(4)3D-RVLS-fre had the highest accuracy for detecting severe MF(area under the curve 0.899 VS 0.804;P=0.0187)compared with 2D-RVLS-fre.Conclusion: 3D-RVLS-fre may be the most accurate functional measure that predict the extent of RV MF in patients with advanced heart failure.