title: A new hydrodynamic approach by infusion of drag-reducing polymers to improve left ventricular function in rats with myocardial infarction.
abstract: BACKGROUND
  Recent studies have shown that drag-reducing polymers (DRPs) prolonged survival time in rats with acute myocardial infarction (MI), but their effect on cardiac function post MI remains unknown. This study sought to test the hypothesis that intravenous infusion of DRPs may improve left ventricular (LV) function in rats following surgically induced MI.
  
  
  METHODS
  MI was induced by ligation of the left anterior descending coronary artery in 36 Sprague-Dawley rats, and sham operations were performed in 12 animals. DRPs were then administered to 18 of the MI rats. Echocardiograpy was used to evaluate the changes of impaired LV function and global wall motion. Besides, the hydrodynamic effect of DRPs on microcirculation was also assessed.
  
  
  RESULTS
  The survival rate at 24h following MI was significantly different among the sham, MI and DRP groups (p = 0.023). DRP-treated animals had marked smaller left ventricular end-systolic diameter and better anterior systolic wall thickness comparison with untreated rats. Significant improvement of fractional shortening and ejection fraction were detected in MI rats with DRP. Wall motion score index and contrast score index were both significantly reduced by DRP treatment. DRPs were shown to have beneficial effects on microvascular variables including red blood cell velocity, diameter, blood flow and calculated wall shear stress in third-order arteriole.
  
  
  CONCLUSIONS
  Acute administration of DRPs improved LV function in a rat model of MI possibly by improving microvascular blood flow due to their unique hydrodynamic properties. DRPs may offer a new approach to the treatment of coronary artery ischemic diseases.
authors.affiliation: Department of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, China.
authors.forename: Xianghui
authors.initials: X
authors.lastname: Chen
authors.forename: Daogang
authors.initials: D
authors.lastname: Zha
authors.forename: Jiancheng
authors.initials: J
authors.lastname: Xiu
authors.forename: Yulin
authors.initials: Y
authors.lastname: Liao
authors.forename: Kai
authors.initials: K
authors.lastname: Cui
authors.forename: Huanbing
authors.initials: H
authors.lastname: Lin
authors.forename: Zhengwei
authors.initials: Z
authors.lastname: Jian
authors.forename: Feng
authors.initials: F
authors.lastname: Hu
authors.forename: Xuliang
authors.initials: X
authors.lastname: Huang
authors.forename: Biying
authors.initials: B
authors.lastname: Zhou
authors.forename: Qiaobing
authors.initials: Q
authors.lastname: Huang
authors.forename: Jianping
authors.initials: J
authors.lastname: Bin
authors.forename: Yili
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000818:Animals; D057446:Hydrodynamics; D007262:Infusions, Intravenous; D008297:Male; D008833:Microcirculation / Q000187:drug effects / Q000502:physiology; D009203:Myocardial Infarction / Q000188:drug therapy* / Q000503:physiopathology; D011108:Polymers / Q000008:administration & dosage* / Q000627:therapeutic use; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D016277:Ventricular Function, Left / Q000187:drug effects* / Q000502:physiology
chemical_list: D011108:Polymers