Experimental evaluation of different microembolization on cardiac systolic synchronism in pigs using realtime contrast echocardiography and speckle tracking imaging

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. Key words: Cardiac resynchronization therapy ; Two-dimentional speckle tracking imaging ; Circumferential strain ; Radial velocity ; Radial strain ;