Image-based Simulation of the Three-dimensional Coronary Blood Flow

The best way to further improve the quality of care in the fields of interventional cardiology and coronary surgery is to devise a computer system that enables clinicians to quantitatively assess the patient's coronary hemodynamics and quantitatively predict the improvements in the perfusion of the myocardium that can be achieved with specific revascularisation measures. We will describe the development of the key components of such a computer system that are intended to provide a basis for patient-specific simulation studies of the three-dimensional flow of blood in the coronary arteries, especially around sections with a stenosis (narrowing). Since stringent time limitations are imposed on our computational tasks, it is necessary to extensively exploit parallelism. Our computer system will be implemented within the framework of the newly-established "Austrian GRID", a GRID infrastructure with large-scale parallelism. Physicians at various sites within a given geographical region will have full access to these facilities. We will give a brief overview of the medical background and the methods employed in the development of our system and then concentrate on patient-specific simulation studies of the three-dimensional blood flow around a stenosis which were done with the finite element method. Patient-specific simulation studies must be based on medical images. This article is merely intended to provide an overview of the required image processing tasks, such as the segmentation of biplane angiograms and three-dimensional reconstruction. We will also, at least in outline form, give a preview of the planed co-registration and image fusion tasks of the three-dimensional reconstructed coronary arteries and 3D perfusion images of the myocardium. The specific problems raised by the segmentation of the angiograms, the three-dimensional reconstruction and the generation of a high-quality mesh in the flow domain will be dealt with in more detail in the companion paper entitled "Imaging and Mesh Generation Issues in Patient-specific Simulation Studies of Coronary Hemodynamics" (Mayr and Quatember 2007).