Simulation and Imaging of the Cardiac System: State of the Heart (Developments in Cardiovascular Medicine Book 43)

The ultrasound velocity tomography allows measurement of cardiac geometries for various phases in the cardiac cycle. The present tomograph makes reconstruc­ tions at intervals of 20 ms. Because of a lack of clear (intramural) landmarks (except the roots of the papillairy muscle), it is difficult to pinpoint spatial trajectories of particular points in the heart. Therefore, a second method was developed of injecting radiopaque markers in the heart and following their motion patterns during the cardiac cycle with help of a biplane X-ray equipment. The data obtained with both methods can be implemented in our finite element model of the heart to compute intramural stresses and strains. The results obtained sofar with the extended Darcy equation to account for the interaction of blood rheology and tissue mechanics look promising. Further testing with more sophisticated subjects than mentioned in Figure 9 is required before it will be implemented in our finite element model of the heart. We conclude that analysis of regional cardiac function, including regional myocardial blood flow, requires still a major research effort but the results obtained sofar justify, to our opinion, a continuation in this direction. Acknowledgement The authors acknowledge Dr. C. Borst and coworkers for doing the animal experiments and prof. Van Campen and dr. Grootenboer for their participation is some aspects of this work. Front Matter....Pages I-XIV Interaction of modern technology and clinical practice....Pages 1-4 Major interacting parameters in a 3-D model of the cardiac system....Pages 5-17 Some physiological aspects in the development of cardiac models....Pages 18-34 The role of mathematical models in an assessment of myocardial function....Pages 35-63 Left ventricular performance and its systolic mechanical properties....Pages 64-75 Three-dimensional models of the heart: advantages and limitations....Pages 76-89 A cardiac model convenient for vascular load coupling....Pages 90-102 Models of ventricular dynamics....Pages 103-116 Material and structural limitations in a 3-D finite element model of the left ventricle....Pages 117-130 General discussion on cardiac mechanics....Pages 131-134 Quantitative 3-D imaging of the heart: myocardium and chambers....Pages 135-150 Three-dimensional analysis of the cardiovascular system....Pages 151-173 Three-dimensional ultrasonic cardiac reconstruction: general aspects and application to finite element analysis of the left ventricle....Pages 174-189 Cardiac imaging and modelling....Pages 190-207 A data acquisition and processing system for ultrasound- and video images and the reconstruction of 3-D images....Pages 208-222 The cardiac and vascular interactions in the regulation of cardiac output....Pages 223-231 Flow within the left ventricular cavity: relative significance of various hemodynamic effects....Pages 232-243 A method for calculating time-dependent epicardial coronary blood flow....Pages 244-257 Multidimensional activation of the heart: The effect of anisotropy in conductivity of cardiac tissue....Pages 258-271 A bidomain model of the ECG: Time integrals and the inverse problem....Pages 272-278 Critical aspects of the forward and inverse problems in electrocardiography....Pages 279-298 Simulation of the cardiac electrical activity sequence using 3-D stochastically distributed parameters....Pages 299-308 Metabolic control of coronary blood flow....Pages 309-322 Neural control of coronary blood flow....Pages 323-330 The interrelationship between the left ventricular contraction, transmural blood perfusion and spatial energy balance: A new model of the cardiac system....Pages 331-357 Physiological factors determining cardiac energy expenditure....Pages 358-376 Constraints in the interpretation of dynamic images of metabolic events....Pages 378-390 Flux analysis of 13 C NMR metabolite enrichments in perfused rat hearts using FACSIMILE....Pages 391-410 The future of the interface between medicine and engineering....Pages 411-418 Closing session....Pages 419-423 Back Matter....Pages 428-433