Background： Renal sympathetic nerves are involved in the reflective activation of the sympathetic nervous system in circulatory control. Catheter-based renal denervation （RDN） ameliorated treatment-resistant hypertension safely, but 10%-20% of treated patients are nonresponders to radiofrequency denervation. The purpose of this study was to investigate the safety and efficiency of cryoablation for sympathetic denervation in a swine model and to explore a new way of RDN. Methods： Seven swines randomly assigned to two groups： Renal cryoablation （CR） group and control group. The control group underwent renal angiogram only. The CR group underwent renal angiogram plus bilateral renal cryoablation. Renal angiograms via femoral were performed before denervation, after denervation and prior to the sacrifice to access the diameter of renal arterial and the pressure of aorta abdominalis. Euthanasia of the swine was performed on 28-day to access norepinephrine （NE） changes of the renal cortex and the changes of renal nerves. Results： Cryoablation did not induce severe complications at any time point. There was no significant change in diameter of renal artery. CR reduced systolic blood pressure （BP） from 145.50 ± 9.95 mmHg at baseline to 119.00 ± 14.09 mmHg. There was a slight but insignificant decrease in diastolic BP. The main nerve changes at 28-day consisted of necrosis with perineurial fibrosis at the site of CR exposure in conjunction with the nerve vacuolation. Compared with the control group, renal tissue NE of CR group decreased by 89.85%. Conclusions： Percutaneous catheter-based cryoablation of the renal artery is safe. CR could effectively reduce NE storing in the renal cortex, and the efficiency could be maintained 28-day at least.
Meng JiLi ShenYi-ZheWuZhi-Feng YaoJia-Sheng YinJia-Hui ChenJian-Guo JiaLing-Juan QiaoPeng LiDJun-Bo Ge
To the Editor:A 35-year-old man who smoked for 15 years suffered from chest pain 12 days ago before admission.He was diagnosed as myocardial infarction.Thrombolytic therapy was given consequently.The electrocardiogram showed sub-acute inferior wall myocardial infarction.Echocardiogram showed attenuated constriction of the inferior wall with an ejection fraction of 59％.On September 5,2013,he was treated with a XINSORB scaffold in right coronary artery (RCA).
目的评价新型全降解聚乳酸西罗莫司洗脱支架(XinsorbTM)在小型猪冠状动脉抑制新生内膜增殖的有效性和安全性。方法裸金属支架(Bare metal stent,BMS)16枚和Xinsorb支架16枚分别随机置入16头小型猪的前降支(16枚)和右冠状动脉(16枚)。置入30d和90d,复查冠状动脉造影后处死部分动物取出支架段血管,将支架分成等长的两部分,一半用树脂包埋后制作硬组织切片,苏木素和伊红染色(haematoxylin and eosin,HE)分析组织形态,评价新生内膜增殖及管腔狭窄率;另一半用戊二醛固定后用扫描电镜观察支架段血管内皮化情况。结果 Xinsorb支架置入后未出现支架内血栓,并有效防止血管弹性回缩造成的血管狭窄。病理分析提示:置入30d,Xinsorb支架比BMS能显著减少新生内膜面积(0.9±0.2)mm2比(2.2±0.2)mm2(P<0.05)和管腔狭窄面积(19.3±3.4)%比(38.2±5.3)%(P<0.05),置入30d时BMS内皮化完全,但Xinsorb支架表面有部分未完全内皮化,Xinsorb支架内皮化完全所需的时间在30～90d。结论 Xinsorb支架在置入小型猪冠状动脉90d内,可以有效地支撑血管壁防止弹性回缩并抑制新生内膜增殖,在置入早期轻度延迟内皮的修复。
