A novel occluder for occluding the left atrial appendage: An experimental study with canines / 第二军医大学学报

ABSTRACT

Objective To adopt a novel domestic double-disc nitinol occluder to occlude the left atrial appendage of canines and evaluate its feasibility, safety and biocompatibility in experimental canine model. Methods Totally 12 healthy dogs were used in this study; their atrial septal was punctured to occlude the left atial appendage via the femoral vein. The position and effect of the implanted occluders were evaluated by electrocardiogram (ECG) monitoring, atrial septal puncture angiography, transesophageal echocardiography (TEE), and pathological examination immediately, 1, 3, and 6 months after the operation. Results Among the 12 dogs, 11were successfully implanted with the occluders immediately after operation, with the occluder in 1 case dropped after the operation. Two cases were firstly implanted with occluders of inappropriate size, which were withdrawn and successfully replaced by appropriate ones. The shape and location of the occluders were good as shown by TEE and left atrial angiography examination, with 3 cases having a little shunt and other cases completely occluded immediately after the operation as shown by TEE and left atrial angiography examination. There was no occluder shift, residual shunt or influence on coronary blood flow at 1, 3, and 6 months after the operation. It was shown that the left atrial appendage was completely blocked at 6 months after operation, and there was no thrombus formation on the surface of occluders or in the left atrium; there was no embolization or infarction in the liver, kidney or spleen, with the surface of the occluders completely covered with endothelial cells. Conclusion The novel self-made nitinol occluder has good biological compatibility, making t feasible to occlude the left atrial appendage via transcatheter approach, with satisfactory middle-term effects.