| Objective: To evaluate the left atrial (LA) function in patients with acute coronary syndrome (ACS) using two-dimensional speckle tracking imaging (2DSTI),and assess the changes of LA function after undergoing percutaneous coronary intervention (PCI) and outcomes of this therapy. Analysis the influences of LA function of ACS patients performed PCI in different time.Methods: 93 patients with ACS accepted the therapy of PCI and 40 age-matched normal individuals acted as a control group were included in the study. Patients with ACS were divided into two groups: unstable angina pectoris group (UA group, n=21) and acute myocardial infarction group (AMI group, n=72). The latter was subdivided into two groups by the time from pain attack to PCI performed: primary PCI group (<12 h, n=51), elective PCI group (5-7d, n=21). In primary PCI group, there are 40 patients with ST segement elevation myocardial infarction (STEMI), 11 patients with Non-ST segement elevation myocardial infarction (NSTEMI). In elective PCI group, there are 8 patients with STEMI and 13 patients with NSTEMI. UA group and elective PCI group were examined by echocardiography within 24 hours of hospitalization, all patients were examined by echocardiography one week, three and six months after PCI respectively.GE Vivid 7 ultrasonic diagnostic apparatus was used to measure some traditional left atrial function indexes, including left atrial maximum volume (LAVmax), left atrial minimal volume (LAVmin) , left atrial passive emptying fraction (LAPEF) , left atrial active emptying fraction (LAAEF) . Strain(S) and Strain rate(SR) were measured at three views(the apical long axis view, 4-chamber and 2-chamber view) by 2DSTI, including LA global longitudinal peak negative strain during atrial systole (GLSs), LA global longitudinal peak positive strain during ventrical systole (GLSr), LA global longitudinal peak positive strain rate during ventrical systole (GLSRs), LA global longitudinal peak negative strain rate during early ventricular diastole(GLSRe) and LA global longitudinal peak negative strain rate during late ventricular diastole (GLSRa). And the average value of three views were calculated, namely LA mean peak negative strain during atrial systole (meanSs), LA mean peak positive strain during ventrical systole (meanSr), LA mean peak positive strain rate during ventrical systole (meanSRs), LA mean peak negative strain rate during early ventricular diastole(meanSRe) and LA mean peak negative strain rate during late ventricular diastole (meanSRa) .Result: 1. In control group, meanSs and meanSRa were significant negative correlation with LAAEF (r = -0.482, P =0.001; r = -0.444, P =0.002),which represent booster pump function of LA. meanSRs was significant negative correlation with LAVmin (r = -0.388,P =0.007) which represent reservoir function of LA, meanSRe was significant negative correlation with LAPEF(r = -0.401, P =0.005) which represent conduit function of LA.2. Compared with control group, patients with ACS (before PCI) had significantly increased in meanSs,meanSRa and LAAEF. LAVmin was significantly increased and meanSRs was significantly decreased in patients. LAPEF and meanSRe were significantly decreased in patients.3. The changes of LA function after undergoing PCI: In UA group: compared with baseline, meanSRs and meanSRe were significantly increased, while meanSRa was significantly decreased at one week after PCI; compared with one week after PCI, meanSRe was further significantly increased at three months after PCI. In primary PCI group of AMI: compared with one week after PCI, meanSs and meanSRa were significantly decreased, while meanSRs and meanSRe were significantly increased at three months after PCI (P<0.01). In elective PCI group of AMI: compared with baseline, these parameters were no significantly difference at one week after PCI; compared with one week after PCI, meanSs and meanSRa were significantly decreased, while meanSRe was significantly increased at three months after PCI (P<0.05); compared with three months after PCI, meanSRa was significantly decreased, while meanSRe and meanSRs were significantly increased at six months after PCI (P<0.05). Compared with elective PCI group at one week after PCI , meanSs and meanSRa were significantly decreased ,while meanSRe and meanSRs were significantly increased in primary PCI group(P<0.05). Conclusions: 1. This study indicates that two-dimensional speckle tracking imaging can represent booster pump function, reservoir function and conduit function of left atrium accurately and quantitatively, which were correlated significantly with traditional left atrial function indexes, such as LAVmin, LAPEF and LAAEF.2. 2DSTI can evaluate the left atrial (LA) function in patients with ACS. In ACS group , conduit function of LA was reduced, while reservoir function and booster pump function were increased in order to ensure the maximum filling of left ventricle.3. In UA group , left atrial function was improved significantly after PCI for one week. In primary PCI group of AMI , left atrial function was improved significantly after PCI for three months. However, in elective PCI group of AMI, left atrial function was improved after PCI for three months, and had further improvement after six month later. Compared with elective PCI group after PCI for one week, left atrial function of primary PCI group was improved obviously.4. Patients with ACS after the therapy of PCI, their left atrial function were improved in some degree with improvement of Left ventricular remodeling, Which means booster pump function and reservoir function of LA were reduced, while conduit function of LA was increased. Patients with ACS accepted PCI in time and early stage can improve LA function significantly.5. Strain and strain rate of 2DSTI can evaluate left atrial overall function quantitately , and valuate the changes of left ventricle and left atrial remodeling after PCI in patients with ACS. |
PDF Full Text Request