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Echocardiographic analysis of cardiac chamber volumes throughout the heart cycle is important to assess left- and right-heart function. We have developed and validated a method to simultaneously segment all four heart chambers in 3D echocardiography cine loops. We described the heart using several Doo Sabin models, one for each chamber and one for the pericardium. The model was fitted to 3D echo images using edge detection and a Kalman filter. The average signed error in estimating volume across all chambers was −1.0 ±± 12.3 ml. These results show that the model slightly underestimates the volumes. Average signed error for the ejection fraction was −3.2 ± 7.4 pts, with the highest error being the right atrium. This all-chamber automatic segmentation method provides high accuracy and may have utility in understanding chamber interactions.

To combat heart disease, clinicians need accurate information about the patient's heart function. Ultrasound images of the heart can be used to provide this information, but analysis of the images is needed to get accurate assessments. This thesis is about new algorithms to measure heart functions related to the heart’s ability to pump blood, these are very important metrics for the heart’s health. In addition, this thesis studies how to automatically find important parts of the heart in the image, which saves time during a medical evaluation. The thesis consists of three papers. The first is about measuring the right ventricle’s ability to pump blood by accurately determining the ventricle’s borders in the image. The second paper is about finding the aorta and the mitral valve centre in certain ultrasound images. This information can be used to determine the standard views, a way of viewing the ultrasound image that gives the clinician much important information. The third paper is about making a single algorithm evaluate all the four chambers of the heart, the idea being that evaluating all at once saves time and that information about one chamber’s position can be used to properly find the other ones.

This thesis is based on a paper by Burglind Jöricke, who found an effective way of constructing the envelope of holomorphy for a domain. This thesis extends the result for domains embedded in n-dimensional complex space.