Study design
This Good Laboratory Practices (GLP) study was designed to evaluate the performance and safety of the study device (Penditure™) in comparison to the control device (AtriClip™* Flex-V™*) in a canine model over 90 days. Twelve mongrel dogs (age range: 10.4–33.6 months) were enrolled in the study. A canine model was chosen because heart size, electrophysiological characteristics, and hemodynamics have been shown to be comparable to those of the human heart.
Six animals were assigned to the Penditure™ device, and six were assigned to the AtriClip™* Flex-V™* device for the 90–day study. A clinical user (interventionalist) performed the implantations.
For each animal, a thoracotomy was performed to expose the LAA. The study or control device was implanted on the LAA. One study or device was implanted per animal. Fluoroscopy was used for guidance.
Transesophageal echocardiography (TEE) was performed post-implantation to evaluate device placement and to confirm LAA closure. Fluoroscopy was also performed for quantitative measurement of the distance between the straight metal segments of the clips to approximate tissue thickness in vivo.
At 7 days and 90 days (before euthanasia) post-implantation, TEE was performed again to evaluate device placement, confirm LAA closure, and document any abnormalities. Fluoroscopy was performed for quantitative measurement of the distance between the straight metal segments of the clips to approximate tissue thickness in vivo.
After the animals were euthanized, a pathological gross examination was performed, and the heart, implant, and major organs (brain, liver, kidney, spleen, lungs) were saved for histopathologic analysis by a veterinary pathologist. Inspection and photographic documentation of the LAA (both external and intra-atrial views) were performed. The clips and surrounding tissue underwent processing for histopathologic evaluation.
