AbstractThe aim of this project was to develop novel quantitative MR techniques to characterise cardiac tissue for the management of cardiac arrhythmias without the use of exogenous contrast agents to improve patient safety and allow scar imaging during and after ablation therapy. This project had a particular focus on driving the innovation that underpins an interventional MRI electrophysiology program, e.g., developing techniques for the assessment of the arrhythmia substrate within the atria and ventricles, guiding risk stratification and intervention planning. These techniques would often relate to substrate analysis for ventricular tachycardia (VT) and atrial fibrosis assessment, including fibrosis/scar quantification and wall thickness. Indeed, MR imaging has been used extensively for characterisation of the arrhythmic substrate for both atrial and ventricular arrhythmias. However, such MR techniques remain imperfect, and substantial clinical impact is anticipated from the development of robust techniques for the assessment of atrial and ventricular substrate. Because the imaging challenge is generally greatest for the thin walled atrial myocardium, techniques are often developed for ventricular imaging in the first instance, as it is the case for this study.
As described in the following Chapters, imaging solutions to the above challenges were implemented during the course of this project. This report lays out the theoretical basis and experimental results of roughly 4 years of research on the area of contrast-free quantitative magnetization transfer imaging for myocardial tissue characterization and in-vivo assessment of myocardial fibrosis in patients.
Chapters 1-4 describe the clinical background, mathematical and physical concepts necessary to understand and evaluate the methods developed herein. Chapters 5-7 describe the methods, experimental results and conclusions obtained. Specifically, Chapters 5 and 6 are adaptations of two manuscripts submitted and accepted1 for publication in peer-reviewed international journals (MAGMA and MRM, respectively). Chapter 7 is the result of the last few months of this project and has not yet been submitted for external review.
As a result of the research carried out, and in addition to the work presented herein, I attended three consecutive annual meetings of the International Society for Magnetic Resonance in Medicine (ISMRM) with abstract presentations and obtained two Magna Cum Laude Awards (2017 and 2019). I also attended and presented an abstract at the annual meeting of the Society for Cardiovascular Magnetic Resonance (SCMR) in February 2019 in the USA and presented posters at numerous events in London (UK) between 2016-2019.
|Date of Award
|1 Jan 2021
|Rene Botnar (Supervisor) & Reza Razavi (Supervisor)