Assessment Of Left Ventricular Myocardial Function By Two Dimentional Strain And Strain Rate

Sectionâ… Quantitative Assessment of Left Ventricular Myocardial Function by Two Dimentional Strain EchocardiaogrophyObjectives To observe S(strain) and SR(strain rate )charasteridtics of different segmental left ventricular myocardial and characteristics of myocardial infarction and non-segmental segments with different extent of left anterior descending(LAD) branch stenosis, then diususs the clinical value of Two Dimentional Strain(2DS) in quantifing different extent of stenosis.Methods Seventy-two Coronary Artery Disease( CAD) patients in the study, 55 patients with non-MI group, in accordance with LAD stenosis further division. Group A: (stenosis less than 50%) included 24 patients in the group; group B: (stenosis between 50% to 75%) included 19 patients; group C: (stenosis greater than 75%) included 12 patients in the group, myocardial infarction (group D) included 17 patients, including eight patients of acute myocardial infarction, and nine patients of old myocardial infarction. Strain and strain rate parameters was measured.with eleven segments of LAD by the use of 2DS.Results Group A left ventricular segmental strain - time curve was regular. Group B the peak strain of relevant segments of LAD decreased compared to group A, but the difference was not statistically significant (P>0.05). Group C the peak strain decreased than group A and B. Group D: strain-time curve distorted, cluttered, the peak strain of some segments decreased significantly, straighted, or peak inverted, the relevant segments of the peak strain were significantly decreased.Group A Strain rate -time curve the peak systolic strain rate (SRs) was sharp, peak time focused. SRs of group B declined compared with group A, but there was no difference statistically. Group C Strain rate -time curve of all relevant segments of LAD distributed, cluttered, peak SRs have declined on different levels, and there was significant difference in some segments compared with group A, group B, (P<0.05). Group D Strain rate -time curve cluttered, peak disappeared, the peak of SRs of the relevant segments decreased significantly, the difference was statistically significant compared with group A (P<0.05, P<0.01), most segments were different significance compared with group B (P<0.05, P<0.01), SRs of some segments was significant difference compared with group C (P<0.05).Strain rate-time curve of group A early diastolic strain rate (SRE) showed a positive high-speed wave, late diastolic strain rate (SRA) showed a narrow low positive wave, SRE was higher than the SRA. SRE of relevant segments of group B decreased slightly, but the difference was not statistically significant (P>0.05). SRE of most segments of group C decreased significantly compared with group A (P<0.05, P<0.01), compared with group B, apical posterior ,apical anterior and apical postseptal were statistically significant difference (P<0.05). Strain rate - time curve of group D, the peak of SRE decreased significantly or disappeared, and the measured value were difference statistically compared with group A and group B (P<0.05, P<0.01), in addition to the basement anteroseptal,other segments had statistical difference compared with group C (P<0.05, P<0.01). There was no significant difference in SRA compared with group A, B, C (P>0.05), SRA of group D decreased significantly, There were statistically difference compared with group A and B (P<0.05, P<0.01), and most segments were statistically significant difference compared with C (P<0.05, P<0.01). group A SRE / SRA>1, group B, C, D SRE / SRA <1.Conclusion 1. Coronary artery stenosis greater than 75%, S, SRs, SRE was significantly decreased, and systolic and diastolic function was significantly decreased; 2. coronary artery stenosis less than 50%, SRE / SRA> 1; stenosis greater than 50% , SRE / SRA <1, diastolic function degrade; 3. peak S, SRs, SRE and SRA of myocardial infarction were significantly lower than that of non-segmental; 4. coronary heart disease and myocardial ischemia, diastolic function demaged earlier than systolic function.Sectionâ…¡Quantitative Assessment of Left Ventricular Myocardial Fonction before and after Revascularization with Coronary Artery Disease by Two Dimensional Strain EchocardiographyObjective To investigate the strain and strain rate characteristics before and after the improving of myocardial ischemia at different time points ,then to discuss the value of 2DS in estimating therapy effect of CAD.Methods 19 patients with revascularization treatment of CAD, to detect the changes of the parameter of strain and strain rate before and after 1 week, 1 month and 3 months of revascularization treatment .Results Before revascularization treatment, strain - time curves and strain rate -time curves of lesion segments cluttered, the peak of S, SRs and SRE declined ,the peak of S of some segments inverted. One week after treatment, the pesk of S, SRs, SRE and SRA of lesion segments have increased, but there was not significant difference (P>0.05). One month after treatment, the peak of S, SRs and SRE of the lesions segments rised in some degree,the peak of S and SRE increasd compared to pre-treatment significantly (P<0.01).One month after treatment, strain - time curves and strain rate -time curves of lesions segments tended to regularity, the peak of S , SRs, SRE and SRA rised significantly , there was significant difference compared to pre-treatment (P<0.01), there was significant difference in the peak of S, SRs, and SRA compared to one week and one month after treatment (P<0.01).Conclusion Two Dimensional Strain imaging can evaluate the strain and strain rate non-invasively and quantitatively at different times after revascularization of coronary heart disease, can evaluate regional myocardial systolic and diastolic function.