RESUMO
Objective:To evaluate the effect of left ventricular hypertrophy and deformation on cardiac function in patients with uremic cardiomyopathy (UCM) by using the technology of two dimensional speckle tracking imaging (2D-STI).Methods:A total of 67 UCM patients were randomly divided into the normal cardiac function group (subgroup A,32 cases) and the abnormal cardiac function group (subgroup B,35 cases)according to the New York Heart Association points (NYHA-P).A total of 30 healthy subjetcs served as the control group.Parameters including left ventricular ejection fraction (LVEF),left ventricular mass index (LVMI),left ventricular spherical index (LVSI),left ventricular myocardial mean radial strain (MRS),mean radial strain rate (MRSR),mean longitudinal strain (MLS),local systolic twist angle (STA),and mitral annulus maximum displacement (TMAD) were detected.Results:MLS,MRS,MRSR,LVSI,STA and TMAD in the Group A and Group B were lower than that in the control group (P＜0.05),and LVMI in the Group A and Group B was increased than those in the control group (P＜0.05);LVEE MLS,MRS,MRSR,LVSI and STAin the Group B was decreased than that in the Group A (P＜0.05).MLS in the Group A and B were positively correlated with LVEF and LVSI,but negatively correlated with LVMI.Using the point of 14.10％ for MLS to evaluate UCM patients with NYHA-P＞4 points,the sensitivity,the specificity and Yuedden index were 90.5％,71％ and 0.585,respectively.STA in UCM patients were lower than that in the control (P＜0.05).Conclusion:2D-STI possesses a unique advantage in detecting left ventricular strain and strain rate on left ventricular regional function in UCM with left ventricular hypertrophy and ventricular deformation.There is no direct correlation between the left ventricular hypertrophy and ventricular deformation,but the ventricular hypertrophy and deformation are correlated with regional cardiac function and clinical cardiac function.Left ventricular regional dysfunction may occur before cardiac hypertrophy and deformation.
RESUMO
Objective To determine the biomechanical parameters of left ventricular by using velocity vector imaging (VVI),and to indirectly assess the coronary artery stenosis with VVI in the patients with coronary artery disease (CAD).Methods 52 patients who had one coronary artery lesions at least diagnosed by coronary angiography (CAG)were divided into coronary artery mild stenosis group and severe stenosis group;2 1 patients in mild stenosis group had one coronary stenosis <75%;31 patients in severe stenosis group had one coronary artery stenosis ≥75% at least.At the same time,20 cases of normal people without coronary artery stenosis showed by CAG were selected as normal control group. VVI was used to detect the left ventricular wall segments of the overall longitudinal strain (GLS ), the overall circumferential strain (GCS ) and the overall radial strain (GRS ). Results The absolute values of GLS,GRS,GCS of the patients in mild and severe coronary artery stenosis groups were significantly decreased than those in normal control group(P<0.05),and the strain parameters in severe stenosis group were decreased more significantly, there were significant differences compared mild stenosis group (P<0.05 ). The distribution of the segments with decreased longitudinal strain matched the LV myocardial segment with the coronary stenosis rate ≥ 75%,and GLS had the most sensitivity.The GLS in normal control group,mild stenosis group and severe stenosis group were negatively correlated to left ventricular ejection fraction (LVEF)(r=-0.58,P<0.05;r=-0.51,P<0.05;r=-0.43,P<0.05).GLS-16.14 % was used to assess the severe coronary artery stenosis with requiring the implementation of PTCA treatment as the diagnostic cut-off point with sensitivity 96.8%, specificity of 70%, the highest Yuedden index 0.668. Conclusion The decreasing of left ventricular strain could be detected by VVI, which suggests that severe coronary artery stenosis exists in coronary artery;the distribution of the segments with significantly decreased strains can be used to assess the coronary lesions and stenosis degrees.