[Pressure load of the aneurysm sac after endovascular treatment of aortic aneurysm].
OBJECTIVE
Stent grafting of aortic aneurysms should result in relief of pressure within the excluded aneurysmal sac, however confirming data are not available. This study evaluates the intra-extraluminal pressure translation and translation of maximum pressure increase (dp/dtmax) into the excluded aneurysmal sac after endovascular treatment of experimental aortic aneurysms.


METHODS
Experimental autologous aneurysms were created surgically using a patch from the sheath of the rectus abdominis muscle in 12 mongrel dogs. After 12 weeks reconvalescence, endovascular treatment was performed viafemoral access using dacron-covered nitinol stents. Spiral CT and angiography were performed at one week and six weeks follow-up and 6 animals each. Laparotomy was performed for hemodynamic measurements. A manometer-tipped catheter was introduced into the excluded aneurysmal sac. A second manometer-tipped catheter was placed intraluminally within the stent graft. Pressure curves and their first derivative dp/dt were simultaneously recorded to calculate the intra-extraluminal transmembraneous pressure transmission.


RESULTS
At one week follow-up systolic blood pressure and mean blood pressure were significantly reduced by factors of 0.60 +/- 0.17 (p < 0.01) and 0.78 +/- 0.3 (p < 0.05), respectively in the excluded aneurysm sac. The maximal pressure increase, dp/dt max, was considerably reduced by a factor of 0.06 +/- 0.05 (p < 0.01). However, the diastolic blood pressure was not significantly changed. There were no hemodynamic differences between one and six weeks follow-up.


CONCLUSIONS
In experimental aortic aneurysms, endovascular treatment with stent grafts significantly reduces the systolic peak pressure and dp/dt max in the excluded aneurysmal sac, and thereby significantly reduces the wall stress in the diseased aneurysm wall. Despite complete exclusion of the aneurysm, a considerable pressure load remains in the excluded aneurysmal sac.
Pitton
M B
MB
Klinik und Poliklinik für Radiologie, Johannes Gutenberg-Universität Mainz.
Düber
C
C
Neufang
A
A
Schmenger
P
P
Icking-Konert
B
B
Bro
S
S
Thelen
M
M
D000792:Angiography; D000818:Animals; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000628:therapy*; D001794:Blood Pressure; D003971:Diastole; D004285:Dogs; D011312:Pressure; D015607:Stents; D013599:Systole; D014057:Tomography, X-Ray Computed