ABSTRACT
Objective To study the influence of different microembolism on left ventricular systolic synchronism in pigs by detecting the real-time dypyridamole stress contrast echocardiography (RT-MCE).Methods Eighteen miniature pigs were randomly divided into three groups and underwent microembolization injection procedure through the middle of anterior descending coronary artery with different numbers of microsphere injection,as:group A(dosage 50 thousands,3 pigs),group B (dosage 120 thousands,8 pigs) and group C (dosage 150 thousands,7 pigs).The peak values and the time-to-peak circumferential strain(Circ.Strain),radial velocity (Radial Vel.) and radial strain (Radial Strain) were obtained both at mitral valve level and papillary muscle level at left ventricle short axis views using two-dimensional speckle tracking imaging(STI)analyzed by Philips Q-Lab 8.1 workshop,respectively.Results No significant difference in the presence of contraction synchrony was observed using RT-MCE.The time-to-peak Circ.Strain of microembolism related segments were prolonged at 1 week after microembolism detecting with dypyridamole stress RT-MCE (P＜0.05,both intro-group and inter-group).While time-to-peak radial strain were extended since 6 hours after the intervention to 1 week after the procedure.Conclusions Dypyridamole stress RT-MCE can be used to measure the myocardial perfusion accurately.The elongation of time-to-peak circ.strain and radial strain were developed with time in microembolism related segments.