Visual Exploration of Cardiovascular Hemodynamics

Abstract

Cardiovascular diseases (CVD) are the most common cause of death worldwideand can lead to fatal consequences for the patient. Relevant examples of CVDs areacquired or congenital heart failures, stenosis and aneurysms. Among the variouscauses of such diseases, hemodynamic information plays an important role and isin focus of current clinical and biomedical research. Thereby, the term hemodynamicscomprises quantitative and qualitative blood flow information in the heart, thevessels or corresponding vessel pathology. This includes, for example, blood flowvelocity, inflow behavior, wall shear stress and vortex structures. Investigationshave shown that hemodynamic information may provide hints about the initiation,existence, progression and severity of a particular CVD. An important partof these investigations is a visual exploration and qualitative analysis, respectively,of the complex morphological and hemodynamic datasets for which the thesis athand achieves new contributions.The data acquisition of the hemodynamic information relies primarily on MRIimaging and simulation, whereby the thesis describes essential data processingsteps for both modalities. Existent visual exploration approaches and relevant applicationareas from the clinical and biomedical research domain are discussed,which are used to derive three research goals of the thesis. These goals consistof the development of a new visualization method to expressively depict vesselmorphology with embedded flow information, an automatic extraction approachof qualitative hemodynamic parameters as well as a flexible focus-and-context approachto investigate multiple hemodynamic information. Although the proposedmethods focus on simulated hemodynamics in cerebral aneurysms, this thesis alsodemonstrates their application to other vessel domains and measured flow data.The achieved results are evaluated and discussed with clinicians as well asbiomedical and simulation experts, who are involved in the data analysis of hemodynamicinformation. The obtained insights are incorporated into recommendationsand challenges for future works in this field.