Feasibility study of the use of left atrial appendage occluder LACBES with animal experiment / 介入放射学杂志

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.

Transcatheter aortic valve implantation assisted with microcatheter: a new method to avoid coronary artery obstruction / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Lack of fluoroscopic landmarks can make valve deployment more difficult in patients with absent aortic valve (AV) calcification. The goal of this article was to evaluate the feasibility and effectiveness of transcatheter implantation of a valved stent into the AV position of a goat, assisted with a microcatheter which provides accurate positioning of coronary artery ostia to help valved stent deployment.</p><p><b>METHODS</b>The subjects were 10 healthy goats in this study. A microcatheter was introduced into the distal site of right coronary artery (RCA) through femoral artery sheath. A minimal thoracic surgery approach was used to access the apex of the heart. The apex of the left ventricle was punctured; a delivery catheter equipped with the valved stent was introduced over a stiff guidewire into the aorta arch. We could accurately locate the RCA ostia through the microcatheter placed in the RCA under fluoroscopy. After correct valve position was confirmed, the valved stent was implanted after rapid inflation of the balloon. The immediate outcome of the function of the valved stents was evaluated after implantation.</p><p><b>RESULTS</b>All ten devices were successfully implanted into the AV position of the goats. Immediate observation after the procedure showed that the valved stents were in the desired position after implantation by angiography, echocardiogram. No obstruction of coronary artery ostia occurred, and no moderate to severe aortic regurgitation was observed.</p><p><b>CONCLUSIONS</b>When the procedure of transcatheter implantation of a balloon-expandable valved stent into the AV position of goats is assisted with microcatheter positioning coronary artery ostia, the success rate of operation can be increased in those with noncalcified AV.</p>

Transcatheter closure of atrial septal defects improves cardiac remodeling and function of adult patients with permanent atrial fibrillation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Permanent atrial fibrillation (AF) is the most common form of dysrhythmia associated with atrial septal defects (ASDs) in patients older than 40 years. However, little is known about cardiac remodeling after transcatheter closure in patients with permanent AF. This study was designed to compare cardiac events and remodeling effects after transcatheter closure in such patients.</p><p><b>METHODS</b>Clinical data of 289 adult patients older than 40 years who underwent ASD closure at our center were analyzed retrospectively. Of them, 63 patients with permanent AF were assigned to the case group, and the other 226 patients without permanent AF were assigned to the control group. Cardiac events and changes in left and right cardiac cavity dimensions before the procedure and 6 months after the procedure were compared between the two groups.</p><p><b>RESULTS</b>Patients in the case group were significantly older than those in the control group. The right ventricular (RV) volume and right atrial (RA) volume were decreased significantly in both the groups during a median follow-up period of 6 months after closure (P < 0.001). The left atrial dimensions, left ventricular end-systolic dimensions, left ventricular end-diastolic dimensions and left ventricular ejection fraction showed no significant change before and after the procedure in both the groups. Changes of the RV volume and RA volume in the case group were significantly smaller than those in the control group (P = 0.005 and P < 0.001). The New York Heart Association cardiac function was improved in both the groups during the 6 months follow-up period.</p><p><b>CONCLUSIONS</b>The transcatheter closure of ASD can improve the cardiac remodeling and cardiac function in patients with or without AF.</p>