Pittfalls of aneurysm sac pressure monitoring

Endovascular aneurysm repair (EVAR) is nowadays a globally applied treatment of abdominal aortic aneurysms (AAAs). The Achilles heel of EVAR is the incomplete seal of the aneurysm sac (endoleak) or the persistence of significant pressure in the aneurysm sac without detectable endoleak (endotension). Therefore, follow-up is needed after EVAR. CT is considered the __gold-standard__ for the detection of endoleak and endotension. However, the CT has several drawbacks. Hence a new follow-up method is needed. This thesis contributes to the development of the rationale of aneurysm sac pressure (ASP) monitoring as follow-up. The aim of this thesis is to evaluate the possible pitfalls of ASP monitoring. The relationship between endoleak and ASP is not clear. Results of different studies are compared and the present knowledge about determinants of ASP is discussed. A model of the human circulation and thrombus analogues are developed and validated. The effect of the ASP measuring technique, the aneurysm sac thrombus, the sensor motion and the direction of ASP measurement on the measurement itself is evaluated. This thesis demonstrates that aneurysm sac pressure is not straightforward. A pressure trend seems more appropriate to follow than absolute aneurysm sac pressures.LEI Universiteit LeidenProfessor Michaël Van VlotenfondsVaatchirurgi

Pittfalls of aneurysm sac pressure monitoring

Endovascular aneurysm repair (EVAR) is nowadays a globally applied treatment of abdominal aortic aneurysms (AAAs). The Achilles heel of EVAR is the incomplete seal of the aneurysm sac (endoleak) or the persistence of significant pressure in the aneurysm sac without detectable endoleak (endotension). Therefore, follow-up is needed after EVAR. CT is considered the __gold-standard__ for the detection of endoleak and endotension. However, the CT has several drawbacks. Hence a new follow-up method is needed. This thesis contributes to the development of the rationale of aneurysm sac pressure (ASP) monitoring as follow-up. The aim of this thesis is to evaluate the possible pitfalls of ASP monitoring. The relationship between endoleak and ASP is not clear. Results of different studies are compared and the present knowledge about determinants of ASP is discussed. A model of the human circulation and thrombus analogues are developed and validated. The effect of the ASP measuring technique, the aneurysm sac thrombus, the sensor motion and the direction of ASP measurement on the measurement itself is evaluated. This thesis demonstrates that aneurysm sac pressure is not straightforward. A pressure trend seems more appropriate to follow than absolute aneurysm sac pressures.</p

Feasibility of Laser Doppler Vibrometry as potential diagnostic tool for patients with abdominal aortic aneurysms

Cardiolog

The effect of short aneurysm neck length on the proximal fixation strength of modern EVAR-grafts. An in vitro study

Study of the normal and pathological locomotory syste

Influence of aneurysm wall stiffness and the presence of intraluminal thrombus on the wall movement of an aneurysm. An in-vitro study

Vascular Surger

The Proximal Fixation Strength of Modern EVAR Grafts in a Short Aneurysm Neck. An In Vitro Study

Objectives: The study aims to measure the strength of the proximal fixation of endografts in short and long necks. Design: Three types of endografts were compared: Gore Excluder (R), Vascutek Anaconda (R) and Medtronic Endurant (R). Materials and methods: The proximal part of the stent grafts was inserted in bovine arteries and the graft was then attached to a tensile testing machine. The force to obtain dislodgement (DF) from the aorta was recorded for each graft at proximal seal lengths of 10 and 15 mm. Results: The median OF (interquartile range, IQR) for the Excluder, the Anaconda and the Endurant with a seal length of 15 mm was: 11.8 (10.5-12.0) N, 20.8 (18.0-30.1) N and 10.7 (10.4-11.3) N. With the shorter proximal seal of 10 mm, DF was, respectively: 6.0 (4.5-6.6) N, 17.0 (11.2-36.6) N and 6.4 (6.1-12.0) N. Conclusions: The proximal fixation of the Anaconda is superior to the Excluder and the Endurant at short necks of 10 and 15 mm in an experimental set-up. There is a statistically significant decrease of proximal fixation for the Excluder stent graft, when decreasing the length of the proximal neck from 15 to 10 mm. (C) 2009 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved

ACE Inhibitors Potently Reduce Vascular Inflammation, Results of an Open Proof-Of-Concept Study in the Abdominal Aortic Aneurysm

Vascular Surger

Long term results of kissing stents in the aortic bifurcation

BACKGROUND: To evaluate the long-term outcome after aortoiliac kissing stent placement and to analyze variables, which potentially influence the outcome of endovascular reconstruction of the aortic bifurcation. METHODS: All patients treated with aortoiliac kissing stents at our institution between April 1995 and August 2011 were retrospectively identified from a prospective single-center database. Data regarding patient characteristics (age, gender, smoking, cardio- and cerebrovascular risk factors, hyperlipidaemia, diabetes mellitus and use of antihypertensive medication), symptoms, pre-interventional examination and imaging, procedural details and follow-up were retrieved. Patency rates were calculated with Kaplan-Meier analysis. Factors affecting the patency were determined with Cox uni- and multivariate analysis. RESULTS: A total of 215 patients (63% men, mean age 61 ± 10 years) were included. The median follow-up period was 31 (IQR 47.1) months. Primary, primary assisted, and secondary patency rates were 97%, 97%, and 99%, respectively, at one month; 92%, 95% and 94% at four months; 75%, 86%, and 91% at two years; 70%, 81%, and 91% at 5 years; and 67%, 81%, and 91% at ten years. Younger age and previous aortoiliac treatment were predictors for reduced primary and primary assisted patency. Smoking, previous aortoiliac intervention, TASC C and D lesions were predictors for reduced secondary patency. CONCLUSIONS: Reconstruction of the aortoiliac bifurcation with kissing stents is feasible, safe and effective in all types of lesions with satisfying long term patencies. TASC C and D lesions are associated with a higher occlusion rate. Younger age and previous aortoiliac interventions are predictors for reduced primary and primary assisted patency

Influence of aneurysm wall stiffness and the presence of intraluminal thrombus on the wall movement of an aneurysm - an in vitro study

Vascular Surger