Evaluation Of Left Ventricular Systolic Function In Patients With Different Coronary Artery Stenosis By Three-dimensional Speckle Tracking Imaging

Objective:This study was designed to determine the value of three-dimensional speckle tracking imaging (3D-STI) in evaluation of left ventricular systolic function in patients with different coronary artery stenosis.Methods:1. Object:133 patients with clinical possible diagnosis of coronary heart disease (CHD) were enrolled in the study, global left ventricular systolic function research enrolled 63 patients and left anterior descending artery (LAD) supplied regional left ventricular systolic function research enrolled 70 patients.2. Groups:(1) Global left ventricular systolic function research:According to the results of coronary angiography, the patients were divided into four groups:the control group with 10 cases without stenosis, the mild stenosis group (coronary stenosis and luminal stenosis rate≤50%) with 9 cases, the moderate stenosis group (50%< luminal stenosis rate≤75%) with 10 cases and the severe stenosis group (luminal stenosis rate>75%) with 34 cases. (2) Left anterior descending artery (LAD) supplied regional left ventricular systolic function research:According to the results of left anterior descending artery (LAD) coronary angiography, the patients were divided into four groups, the control group with 18 cases without LAD stenosis, the mild stenosis group (left anterior descending artery stenosis and luminal stenosis rate≤50%) with 15 cases, the moderate stenosis group (50%< luminal stenosis rate≤75%) with 15 cases and the severe stenosis group (luminal stenosis rate>75%) with 22 cases.3. Parameters and Analysis:The global echocardiographic parameters included global long axis strain (GLS), global radial strain (GRS), global circumferential strain (GCS) and global area strain (GAS). The regional echocardiographic parameters included long axis strain (LS), radial strain (RS), circumferential strain (CS) and area strain (AS).The differences of these parameters between the different groups were compared.Results:1. GAS in mild stenosis group was significantly decreased compared with control group (P< 0.05). In moderate stenosis group, GLS, GRS, GAS were significantly lower than control group while GAS was also significantly lower than mild stenosis group (P<0.05). Compared with other groups, global strains parameters were significantly decreased in severe stenosis groups (P<0.05).2. Results of the regional echocardiographic parameter:(1) Results of Long axial strain (LS):the mild stenosis group has no significant difference were observed compared with the control group. Long axial strain of moderate stenosis group was significantly lower than control group (P<0.05), and part of the segments (AA、AS) long axis strain was significantly lower than mild stenosis group (P<0.05); the other segments long axis strain of moderate stenosis group have no significant difference were observed compared with the mild stenosis group. Each segment long axial strain of severe stenosis group was significantly lower than control group, the mild stenosis group and moderate stenosis group (P<0.05).(2) Results of radial strain (RS):the mild stenosis group has no significant difference were observed compared with the control group. BAS segment radial strain of moderate stenosis group has no significant difference were observed compared with the control group; the other segments radial strain was significantly lower than control group (P<0.05). MA. AA and A segments radial strain of moderate stenosis group was significantly lower than mild stenosis group; the other segments radial strain of moderate stenosis group has no statistical significance difference compared with mild stenosis group. Each segment radial strain of severe stenosis group was significantly lower than control group and mild stenosis group (P<0.05), but the difference compared with moderate stenosis group had no statistical significance.(3) Results of circumferential strain(CS):the mild stenosis group has no significant difference were observed compared with the control group.BAS^ AA and A segments circumferential strain of moderate stenosis group has no significant difference were observed compared with the control group; the other segments circumferential strain was significantly lower than control group (P<0.05), moderate stenosis group each segment circumferential strain has no statistical significance difference compared with mild stenosis group. Each segment circumferential strain of severe stenosis group was significantly lower than control group, the mild stenosis group and moderate stenosis group (P<0.05).(4) Results of area strain (AS):Each segment area strain of mild stenosis group was significantly lower than control group (P<0.05). Each segmental area of strain moderate stenosis group was significantly lower than control group (P<0.05), and part of the segments (BA、BAS) was significantly lower than mild stenosis group (P<0.05), the other segments area strain has no significant difference were observed compared with the mild stenosis group. The strain of severe stenosis group was significantly lower than control group, mild stenosis, and moderate stenosis group (P<0.05).Conclusion:3D-STI can be used for evaluation of left ventricular systolic function in patients with different coronary artery stenosis. Area strain is a more sensitive parameter for detecting myocardial strain change in mild coronary stenosis.