Fundamental Research About The Rabbit Modle With Tachycardia Cardiomyopthy Indued By Premature Stimulation In Pairs

Objective:(1)、 To establish the tachycardiomyopathy animal model of premature ve ntricular contractions in pairs;(2)、 Explore the time course of recovery of left ventricular systolic dysfunction and structure in patients with premature ventricul ar contraction-induced cardiomyopathy.(3)、 Discuss the influence of the perindop ril captopril on tachycardia cardiomyopathy`s function recovery course after rem oval premature beat. Methods:(1)、The objects and groups of this study: 30 New Zealand rabbits(purchased from the Changsha City Tianqin Biotechnology Co.Ltd.), License Number: SCX(Hunan) 2009-0012);wre all foot-month-old male, with an average weight of 2.5 ± 0.5 kg;divided into Control groups( groups A, n=10) and Pacing groups(groups A, n=10 and groups B, n=10)。(2)、Implanted pacemaker electrode and making tachycardia cardiomyopathy rabbit model :All groups,Via right anterior vena cava,were implanted with 5F arterial sheath,along which 10-pole coronary sinus electrode was sented to right ventricular of New Zealand rabbits。And then, Groups B and groups C have four weeks pacing by the rhythm in pairs.(3)、Drug intervention: After four weeks pacing, groups C begain drug intervention(Feeding with perindopril captopril tablet,producted by servier tianjin pharmaceutical, bought in hunan province people’s hospital.)But, groups A and groups B without any drug intervention.(4)、Observed indicators:maping the left ventricular end-diastolic diameter(LVEDD), end systolic diameter(LVESD) and left ventricular ejection fraction(LVEF) of the New Zealand rabbits with cardiac color Doppler,before and after four week`s pacing, along with the following weeks( the second the forth、the eighth and twlfth weeks). At the same time,measuring the serum levels of MMP-9, TIMP-1, BNP concentration of New Zealand rabbit.The changes of the above indicators among the control groups and the groups A、B. And the Recovery time about those。 Results:(1)、The status of the animls:In the control groups,one rabbit died of anesthesia accident。Each group have one fail to implant arterial sheath,and all died of acute pulmonary edema。After 10 days of pacing,pacing group animals begain to have early symptoms of cardiac insufficiency,such as fatigue, loss of appetite。In the groups B,two animals died of acute pulmonary edema,While,the groups C have one。No animals have infection。To the end,survive and meeting the requirements of the experimental animals: groups A, n=8, groups B, n=7, groups C,n=8.(2)、The result of the establish of tachycardia cardiomyopathy rabbit model induced by pacing with the rhythm in pairs :Compared with the control groups and pacing groups,after four weeks pacing, the LVEDD and LVESD was enlarger,LVEF was dropped. the level of TIMP-1 was decreased,the level of BNP、MMP-9 was increased,significantly, p〈0.05.While compared with the groups B and groups C,There are no significant differences in the LVEDD 、LVESD 、LVEF、the level of TIMP-1、BNP and MMP-9.It dedicated that the model of tachycardia cardiomyopathy induced by pacing with the rhythm in pairs was established。(3)、Cardiac structure and function recovery after termination of pacing :Stop pacing for two weeks,the LVEDD and LVESD seems to be smaller,and the LVEF was to increase,and to the 12 th week,almost recovery to the pacing before。The same to the level of TIMP-1、BNP and MMP-9,which completely recovered at the end of the the 12 th week(4)、The influence of the perindopril captopril on tachycardia cardiomyopathy`s function recovery course after stop pacing. Compared to groups B,groups C seems to have smaller LVEDD、LVESD and highe LVEF. It seems to completely recovery at the end of the the 8th week,which is shorter than the group B。So do the level of TIMP-1、BNP and MMP-9。 Conclusion:(1)、 No X-ray, a thoracic vein with electrode mapping procedure to stimulate and successfully establish paired ventricular premature of tachycardiomyopathy animal model,and is simple and easy to operate;(2)、Timely termination of premature ventricular contractions can make heart failure and enlargement of the heart reversed completely.(3)、 Perindopril captopril can inhabite the myocardial fibrosis, and shorten the cardiac structure and function recovery time.