Clinical Research On Left Ventricular Systolic Synchrony After Coronary Artery Bypass Grafting

Objective:Sinceleft ventricular systolic synchrony is closely related with cardiac function, we use CMR to assess the left ventrcular systolic sychronyand analyse the relation between EF and left ventricular systolic dyssynchrony by comparing the systolic synchronic parameter(SSP) of healthy volunteers and patients with old myocardial infarction(OMI).To assess the effciency of CABG by comparing the SSP of patients after CABG and the SSP of different coronary artery territories after surgery.Methods:From 2010 to 2015,30 healthy subjects and 35 patients with OMI hospitalized in General hospital PLA were enrolled with 12 cases having CABG.All cases received CMR and the datum were analysed by 4D LV-analysis(?)MR software. The volume parameters(LVEDV, LVESV, EF and SV), SSP(DISPES,SDI,Pre-contr and Post-contr) and volume-time curve(VTC) of LV 17 segments were acquired therefore.1.Compare the SSPs of patients with OMI and healthy volunteers and analyse the change of patients'SSPs with OMI.2.Study the correlation between the EF and LV systolic dyssynchrony.3. Analyse the changes of patients'SSPsafter CABG.4. Analyse the changes of SSPs of different coronary artery territories after surgery.Results:1. The VTC of patientswith OMI was in a mess with bad consistency, and the SSPs were significantly larger than those of healthy subjects which indicates that the systolic synchrony decreased significantly after OMI.2. EF was moderately and negatively correlated to LV Systolic Dyssynchrony.3. The VTC of patients after CABG improved with better consistency, and the SSPs were significantly lower before the surgery which indicates that the systolic synchrony improved significantly after CABG.4.The SSPs of LAD territories improved significantly after CABG which indicates that the artery graft was better than vein graft at improving the systolic dynsynchrony. And the sequential vein graft has no difference with insequential vein graft.Conclusions:In this research, we use CMR to initially study LV systolic synchrony. We found that the patients with OMI had worse systolic synchrony than healthy subjects and were prone to havesystolic dyssynchrony, and the EF was moderately and negatively correlated to LV systolic Dyssynchrony. We also found that the CABG can improve the patients' ystolic dyssynchronic condition and artery graftcan improve systolic dynsynchrony better than vein graft after surgery.