Inaccurate placement and/or incomplete sealing of the zenith aaa endovascular graft within the vessel may result in an increased risk of endoleak, migration or inadvertent occlusion of the renal or internal iliac arteries.
Parallax is the apparent displacement of an object caused by change in observation position.
In attempting to place the first stent body close to the renal arteries as possible, if the operator does not take into account the anterior/posterior angulation of the abdominal aorta, it is possible to deploy the graft too low and not take advantage of the entire infrarenal neck.
To minimize parallax, the object of interest must be in the center of the screen with the fluoroscopic beam perpendicular to the object being imaged.
As the object of interest gets further from the center of the image, the divergent properties of the x-ray beam tend to distort the image.
The assessment of the surrounding factors regarding the renal artery occlusion found operator error to have been the primary cause of the incident.
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Zenith main body graft was introduced via a left femoral artery.
During the deployment process, a minor adjustment was made to the table in order to better observe the contralateral side.
Before deployment of the main body graft another injection of contrast was not applied ensuring the positioning of the graft to the renal arteries.
Main body graft was deployed, not noting at the time that 1-2 millimeters of fabric material was covering the orifice of the left renal artery.
Mid-procedure, the impingement of the graft upon the left renal artery was noticed.
To resolve the restricted flow through the renal artery, another manufacturer's stent was deployed in the vessel and inflated.
After the renal stenting was performed, good blood flow was observed to the left kidney.
Clear visualization of the proximal portion of the main body graft showed the proximal gold marker had been pushed downward.
After ballooning of the seal and junction sites patency of both renal and internal iliac arteries were noted.
No endoleaks were viewed at the conclusion of the procedure.
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