Low molecular weight heparin microcapsule coated occluder for atrial-septal defects.
BACKGROUND
Whether the low molecular weight heparin microcapsule coated occluder is helpful to endothelialization in atrial-septal defect models is uncertain. This study aimed to investigate the best conditions for low molecular weight heparin coated NiTi alloy occluder and provide the evidence of the efficacy and safety of atrial-septal defect occluders in vivo.


METHODS
Low molecular weight heparin microcapsules were investigated using gelatin as microcapsule material. The prepared low molecular weight heparin gelatin particles were subjected to nickel and titanium alloy occluder coating by sodium hyaluronate. A dog model of atrial septal defects was established after treatment with low molecular weight heparin microcapsule coated occluder (n = 4) and uncoated occluder (n = 4). Endotheliocytes and fibroblastic cells in occluders were observed. And the rate of endothelialization was detected.


RESULTS
When the concentration of gelatin was 1%, the diameters of particles were mostly about 100 microm, and the particle size was uniform. The envelope efficiency of low molecular weight heparin microcapsule was about 80%. The endothelialization of occluder in the model was more obvious in the coated group than in the uncoated group (P < 0.0001).


CONCLUSIONS
Low molecular weight heparin can be prepared into microcapsules with their particle size in nanometric grade. The antithrombotic properties are kept in the nickel and titanium alloy occluder successfully coated with sodium hyaluronate. The endothelialization after the interventional occlusion in the coated group is obvious, indicating that low molecular weight heparin is helpful to the growth of endothelial cells in the occlude and the healing after the interventional occlusion.
Sun
Yong
Y
Department of Cardiology, Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang 150086, China.
Wu
Jian
J
Zhang
Ruo-Xi
RX
Shi
Xiu-Jie
XJ
Liu
Hai-Xia
HX
Zhao
Yang
Y
Yu
Bo
B
D000497:Alloys / Q000737:chemistry; D000818:Animals; D000925:Anticoagulants / Q000494:pharmacology*; D002214:Capsules / Q000737:chemistry; D004195:Disease Models, Animal; D004285:Dogs; D042783:Endothelial Cells / Q000187:drug effects* / Q000648:ultrastructure; D005347:Fibroblasts / Q000187:drug effects; D005780:Gelatin / Q000737:chemistry; D006344:Heart Septal Defects, Atrial / Q000188:drug therapy; D006495:Heparin, Low-Molecular-Weight / Q000737:chemistry / Q000494:pharmacology*; D007150:Immunohistochemistry; D046529:Microscopy, Electron, Transmission; D010316:Particle Size; D011897:Random Allocation
D000497:Alloys; D000925:Anticoagulants; D002214:Capsules; D006495:Heparin, Low-Molecular-Weight; D005780:Gelatin