[Transvenous atrial septal defect occlusion in an animal experiment]

Preliminary results concerning the occlusion of experimental atrial-septal defects (ASDII) of the secundum type are reported. An occlusion element was inserted transvenously and its passage across the atrial-septal defect was controlled by open-heart surgery in dogs. Subsequently, the defect was occluded using a single-piece element. In all 5 surgical experiments the occlusion was possible without dislocation or embolism of the element during an atrial stimulation of the heart for more than 1 hour. In additional experiments without open-heart surgery, atrial-septal defects were produced in 7 dogs by transseptal punction and perforation under X-ray control. The atrial-septal defects could be closed for a short time in 2 dogs. In 1 of the 2 dogs the element embolized into the right pulmonary artery, and in the other into the abdominal aorta. Transvenous occlusion of experimental atrial-septal defects is possible, but more experimental work is necessary with respect to the technical problems.