Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 23 for “"Left Atrium"”.
-
CyberCardia: Patient-specific electrophysiological heart model for assisting left atrium arrhythmia ablation
… the procedure, catheters are inserted into the left atrium to map the atrium geometry and record endocardium electrograms that are then converted into electroanatomical maps to pinpoint the arrhythmia source locations. However, identifying these sources is challenging. The electrograms are …
-
The Influence of Sex and Age on Myocardial Gene Expression in the Left Ventricle and Left Atrium of both Young and Adult Healthy Male and Female Cats
… hearts has not been investigated. We analyzed left ventricle (LV) and left atrium (LA) myocardial tissue samples from young and adult cats and hypothesized that mRNA profiles in both chambers would exhibit sex and age-specific differences. The aims were to compare RNA-sequencing data between 1) …
-
Segmentation and visualization for cardiac ablation procedures
… a method for the automatic delineation of the left atrium in magnetic resonance (MR) images acquired during the procedure. The high anatomical variability of the left atrium shape and of the pulmonary veins that drain into it presents significant difficulties for cardiac ablation. Consequently, …
-
Unterschiedliche autonome Innervation in Pulmonalvene, linkem Vorhof und rechtem Vorhof : eine elektrophysiologische und pharmakologische Charakterisierung
… refractory periods in pulmonray veins, right atrium and left atrium and correlated these functional properties to the underlying neuromorphology. Both raising intraatrial pressure and high intesity stimulation significantly decreased effective refractory period. In 36 Langendorff-perfused …
-
Automatic segmentation of wall structures from cardiac images
… the ventricles from CT images and extract the left atrium from MR images. As applications, the segmentation results are used to facilitate cardiac disease analysis. Specifically, 1. An automatic method is proposed to extract the ventricles from CT images by integrating surface decomposition …
-
Mapping the Characteristics of Atrial Activation Patterns During Atrial Fibrillation
… temporary wire electrodes sutured to the right atrium (RA), the left side of Bachmann’s bundle and posterior left atrium. During AF, a regular rhythm was recorded during four of six episodes from the left atrium, while an irregular rhythm with varying AEG morphologies and CLs was present in the …
-
Multifunctional soft robotic devices and cardiac benchtop models for improved therapy delivery and development
… the development of benchtop models of the left atrium and left atrial appendage that enable device testing, development, and procedural training, and replicate (patho)physiological hemodynamics and motion. Taken together, this thesis research aims to create new therapeutic approaches that …
-
Mitral insufficiency due to ruptured chordae tendineae
… recognizable paradoxical pulsation of the left atrium was present in some of them. At cardiac catheterization a tall left atrial “v” wave with peak pressure as high as or higher than the peak pressure in the pulmonary artery was constantly found.</p><p> In a patient with mitral …
-
The role of myocardial fibrosis and ventricular mechanical dyssynchrony in the pathogenesis and treatment of contractile myocardial dysfunction.
Structural and functional abnormalities of the left ventricle and atrium are important prognostic factors in patients with cardiovascular disease. Dysfunction of the left ventricle in heart failure exposes the left atrium to elevated pressures during diastole, which result in adverse left atrial …
-
A 3-Dimensional In Silico Test Bed for Radiofrequency Ablation Catheter Design Evaluation and Optimization
… arrhythmogenic areas from the rest of the atrium. The standard <em>in vitro</em> evaluation of ablation catheters through lesion studies is a resource intensive effort due to tissue variability and visual measurement methods, necessitating large sample sizes and multiple prototype builds. A …
-
Four-Dimensional Cardiac Magnetic Resonance Analysis in Patients with Atrial Fibrillation
… primarily due to thrombus formation in the left atrium (LA) and left atrial appendage (LAA). while electrophysiological mechanisms of AF are well defined, the LA structural and functional remodelling drives AF onset, persistence, and stroke risk remains incompletely understood. Building on …
-
MODERNIZATION OF THE MOCK CIRCULATORY LOOP: ADVANCED PHYSICAL MODELING, HIGH PERFORMANCE HARDWARE, AND INCORPORATION OF ANATOMICAL MODELS
… pivotal role as the in vitro assessment tool for left heart medical devices. The standard design employed by many research groups dates to the early 1970's, and lacks the acuity needed for the advanced device designs currently being explored. The necessity to update the architecture of this in …
-
Mechanisms of Left Atrial Enlargement in Obese Individuals
… Obesity is linked to diastolic dysfunction and left atrial enlargement (LAE); however, the mechanisms responsible for LAE in obesity are unknown. Previous studies have demonstrated that LAE is directly related to diastolic dysfunction [1], though the influence of obesity on this association is …
-
Closed mitral valvotomy in pregnancy
… fixed valve area obstructs blood flow from the left atrium to the left ventricle, causing pulmonary congestion and oedema. Careful and regular follow up of these patients is essential, and surgery is indicated if optimal medical management fails. Cardiac surgery duting pregnancy represents a …
-
The Effect of Preload Reduction on Parameters to Evaluate Left Ventricular Diastolic Function
… has been proposed as a new index representing left ventricular(LV) relaxation and related to LV filling pressure. This index has been reported as a preload independent parameter in experimental canine model. The impact of preload on this index, however, has not been studied in human. The …
-
Comparison of echocardiography and computed tomography for characterization of cardiac clots in cats with heart disease
… contrast (SEC or “smoke”) within the left atrium and left auricle. In humans, trans-esophageal echocardiography (TEE) is the gold standard, however computed tomographic angiography (CTA) is becoming more widely used to assess detection of left atrial thrombi precluding the use of …
-
Predicting pulmonary hypertension and outcomes in patients with left heart disease
… chronic infectious diseases, lung diseases and left heart diseases (LHD). It is a global health problem and accounts for a substantial portion of cardiovascular disease. PH due to LHD (PH-LHD) is credited to be the most common form of PH worldwide and is associated with adverse outcomes. …
-
In-vivo-Implantation der Mikrodiagonalpumpe II beim Kalb : Hämodynamik und Hämolyse
… 80-90 kg for seven days. It was placed in the left thoracotomy via a left-sided thoracotomy. The inflow cannula was inserted into the left atrium and the outflow cannula was anastomosed with the descending aorta. Pump flow was adjusted to 2_3l/min. Blood samples were taken daily during the …
-
Optimisation of Surgical Timing in Rheumatic Mitral Valve Disease
… Chapter 5 demonstrates the potential role of the left atrium in the management of rheumatic mitral valve disease. It finds that left atrial ejection fraction is the strongest and most reliable predictor for developing a guideline indication for valve intervention in the subsequent two-years. …
-
Die Mikrodiagonalpumpe : tierexperimentelle Untersuchung eines Linksherzunterstützungssystems unter besonderer Berücksichtigung des Thromboembolie-Risikos
… of this study was therefore to evaluate a new left ventricular assist device, developed from the Institute of Biomedical Science in Aachen, in an animal study. This “microdiagonal blood pump” is a non pulsatile device, which is suitable for an intrathoracic implantation. In this approach the …
Page 1 of 2