Echocardiography Evaluate The Effect Acute Exercise On Myocardial Systoiic Function

Objective:This study focuses attention on the variation of swimming athletes whilethey experience acute excise，it have been be observed that the myocardial strain，and cTnTis changing instantaneously, discussing the effect of acute exercise onathletes myocardial strain and the correlation between myocardial strain and cTnT. Inaddition, this study probes into the function of two-dimensional strain parameter inthe evaluation of the partial and whole athletes myocardial function, and opens up thediagnostic value of athletes myocardial damage.Method:15swimming athletes are selected as research object(male=9,female=6),average age is16.33±1.95years, average training period is7.07±2.12years,5excellent athletes,8first class athletes,2second. Drawing the support ofechocardiographic speckle tracking imaging technology, two-dimensional ultrasoundimages of apical four chamber,apical two chamber and apical long axis instantlybefore exercise4hours ago and after exercise4hours later were sampled, we collectvenous blood and separate serum,detect cardiac troponin T, cardiac troponin I,creatine kinase, creatine kinase isoenzyme from each athlete. Ultrasonic image isanalyzed by two-dimensional SRI method, the software automatically divideventricular segmental wall into18segments, recording the global strain(GS) andsystolic global strain rate(S) of ventricular segmental wall. Research data is analyzedby SPSS17.0and Excel in microcomputer. The test of data normality was performedthrough SPSS17.0. Paired T test and bivariant analysis are adopted for the before andafter exercise data which follows the normal distribution use to analyze correlationrelationship and calculate Pearson correlation coefficient. For the before and afterexercise data which does not follow the normal distribution, Wilcoxon’s Sign RankTest was used. As for the comparison between groups, we use Kruskal-Wallis H test.P <0.05stands for the statistical difference, P <0.01shows statistically significantdifference.Results:1. The variation features of myocardial strain before and after exercise are as follows：the myocardium of posterior wall, posterior septal, inferior wall, lateral wall andanterior wall lower the strain absolute value among basal segment intermediatedsegment significantly. Meanwhile, the myocardium of ventricular wall on apicalsegment is not obviously effect the myocardial strain absolute value. The systolicpeaks of posterior wall, posterior septal, inferior wall and lateral wall were distributedregularly, that is, apical segment>middle segment>basic segment, while inferior andposterior walls are exceptions.2. The variation features of the before and after myocardial strain rate are：there existgroup difference on different walls for the3segment myocardial peak systolic strain;peak systolic strain of6walls are distributed regularly, that is, apical segment>middlesegment>basic segment.3. For the before and after exercise period, the comparisons between the whole leftventricle and segment peak systolic strains are: after exercise, heart rate increases rapidly, the strain of the whole left ventricle declines significantly; for all of the walls,apical and middle peak systolic stains descend significantly, except for space before,the descend of the other walls is significant in statistical value, on the contrary, thevariation of apical peak systolic strain is not significant.4. For the before and after period, the variation of cardiac troponin T concentrations is:after the exercise, cardiac troponin T concentrations increases significantly.5. The relation between indicator of myocardial damage and myocardial strain rate is:cTnT negativly correlate to apAntSept S.Conclusions:1.Athlete’s overall or partial contraction function of the heart will be weakened afterexercise, but its effect on the apex segment is not significant.2.The exercise boosts releasing function of cTnT, it could be related to the weakeningof the side wall heart contractile function.3. Drawing support from the Two-dimensional Strain Echocardiography Technology,independently evaluating influence on contraction function of the entire or partial leftventricle exerted by exercise is performed, quantitative assessing and positioning themyocardial function of left ventricle and myocardial damage of the athletes.