Abstract: Abstract: Objective To evaluate the papillary muscle function in patients with ischemic mitral regurgitation (IMR) before and after percutaneous coronary intervention(PCI) using two-dimensional speckle tracking imaging (2D-STI) technique. Methods Seventy-two patients with myocardial infarction were selected and divided into 2 groups, the anterior myocardial infarction group (Ant-MI group, n=33) and the inferior myocardial infarction group (Inf-MI group, n=39). The papillary muscle function was evaluated by echocardigraphy and 2D-STI technique 48 h before PCI and 3 months after PCI. Data of the left ventricular end-diastolic diameter (LVEDd), the left ventricular end-diastolic and end-systolic volume (LVEDV / LVESV), the left ventricular ejection fraction (LVEF) and the mitral regurgitation volume were measured by echocardiography. Data of the longitudinal strain (APM-S, PPM-S), the peak time (APM-T, PPM-T) and the delay time (DT=|APM-T - PPM-T|) of mitral anterior and posterior papillary muscles were measured by 2D-STI technique. Results There were no significant differences in LVEDd, LVEDV, LVESV, LVEF, and mitral regurgitation volume between two groups. Compared with the PCI opertion before, the LVEF was significantly increased, the LVESV and the mitral regurgitation volume were significantly decreased after PCI opertion in both groups (P＜0.05)，and there were no significant changes in LVEDV and LVEDd (P＞0.05). The values of |APM-S| was lower and the |PPM-S| was higher in Ant-MI group than those of Inf-MI group, neither before nor after PCI opertion (P＜0.05). After PCI operation: the |APM-S| was signigicantly increased and the DT was significantly decreased in Ant-MI group (P＜0.05). There were no signigicant changes in |PPM-S|, APM-T and PPM-T (P＞0.05). The |PPM-S| was signigicantly increased and DT was significantly decreased in Inf-MI group (P＜0.05), and there were no significant changes in |APM-S|, APM-T and PPM-T (P＞0.05). Conclusion The 2D-STI technology can be used to evaluate the function of mitral papillary muscles. PCI can significantly improve the papillary muscle function in patients with mild to moderate IMR, reduce the reflux and improve the left ventricular remodeling.

Key words: two-dimeonsional, echocardiography, speckle tracking imaging, ischemic mitral regurgitation, myocardial infarction, percutaneous coronary intervention