The Impact of an Abdominal Aortic Aneurysm on Aortic Wave Reflection

The economical growth and increased welfare in the Western world have a reverse side, with an increased death toll due to cardiovascular diseases. Among these, aortic aneurysms (a local dilation) are particularly lethal as they may grow unnoticed until rupture occurs. In this study, we assessed the impact of the presence of an abdominal aortic aneurysm on arterial hemodynamics and wave reflection in particular. Experimental and numerical methods were applied. Linear wave separation was used to quantify the reflections; wave intensity analysis was applied to assess the nature of the reflected waves. In both the experimental and numerical models, negative reflections were found in the upper aorta corresponding to a backward expansion wave caused by the sudden expansion of the aorta. A numerical parameter study demonstrated that larger diameters and more compliant aneurysms generate stronger negative reflections.