RESUMO
Objective To introduce a self-developed left atrial appendage occluder,LACBES,and to explore the clinical feasibility of using it for the occlusion of left atrial appendage (LAA).Methods Eight healthy canines were used in this experimental study.The LAA of each canine was occluded with LACBES occluder through trans-femoral vein approach.After the procedure of occlusion,the compression ratio of the occluder was calculated,the residual shunt was assessed by left atrial angiography.The left atrium pressure was monitored before and after the procedure,and the immediate effect of LAA occlusion on the left atrium pressure was statistically analyzed.Results Implantation of LACBES occluder was successfully accomplished in all the eight canines.The compression ratio of the occluders ranged from 10％ to 15％.Small amount of postoperative residual shunt was detected in one canine.After occlusion two canines died of procedure-related complications,including shifting of occluder and formation of hematoma at puncturing site.No device-associated death occurred.After occlusion,the left atrial systolic pressure increased instantly,which went up from preoperative (25.4±2.8) mmHg to postoperative (27.5±3.4) mmHg (P＜0.05),but it returned to the baseline of (25.4±2.8) mmHg within 15 minutes.Conclusion For the occlusion of LAA,the use of LACBES occluder carries higher instant success rate and lower residual shunt rate with less device-associated complications,although the left atrial systolic pressure has a transient rising immediately after the occlusion.Therefore,it is expected that LACBES will be able to be applied in clinical practice.
RESUMO
<p><b>OBJECTIVE</b>The purpose of this study was to determine the feasibility of transcatheter pulmonary valve replacement in sheep up to 6 months post procedure.</p><p><b>METHODS</b>Fresh sheep pericardium treated with a 0.6% glutaraldehyde solution for 36 hours was sutured to a valvular ring and then fixed onto a newly designed nitinol self-expandable stent. Thoracotomy was performed in sheep (23.5 +/- 3.1) kg under general anesthesia and the device was delivered into the native pulmonary valve of the sheep via the anterior wall of right ventricle by catheter and fooled for 6 months.</p><p><b>RESULTS</b>One sheep died 4 months after the procedure due to in-stent thrombosis. Another 4 animals survived the 6-month observing period. Angiographic and hemodynamic measurements confirmed good positioning and function of the stents with a competent valve immediately post procedure and 6 months post the procedure in surviving animals.</p><p><b>CONCLUSION</b>Implantation of the nitinol self-expandable stent in the pulmonary valve position by a transcatheter approach is feasible and good function of transcatheter implanted memory nitinol valved stents was shown after 6 months of implantation in sheep.</p>