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Cardiac magnetic resonance imaging (MRI) is a proven technique for the evaluation of myocardial structure and function. An introduction to cardiac physiology is presented in Chapter 1, wherein a measure of LV rotational mechanics called LV twist is defined. LV twist is the apparent rotation of the LV apex relative to the LV base and provides insight into LV function beyond that traditionally reported in measures like ejection fraction. Importantly, cardiac MRI techniques are very well suited to evaluating cardiac structure and function and these methods are outlined in Chapter 2. In particular, MRI tagging can be used to non-invasively generate myocardial tissue landmarks that facilitate the qualitative and quantitative assessment of left ventricular (LV) myocardial deformation in both research and clinical settings. This thesis focuses on several developments. First, we developed a new tagging technique called complementary radial tagging (CRT) that generates a tagging pattern that better matches the annular shaped LV myocardium in the short-axis view. CRT also has better tag contrast during late diastolic phases and can be used to accurately measure the LV mechanics during all cardiac phases (Chapter 3). In parallel with the development of the CRT technique we used conventional clinical tagging protocols to measure LV rotational mechanics quantitatively. Myocardial fibrosis is known to frequently occur in patients with Duchenne Muscular Dystrophy (DMD). The consequences of myocardial fibrosis on LV mechanics, however, are incompletely understood. In Chapter 4 we report on the LV rotational mechanics in patients with DMD with or without myocardial fibrosis. The results suggested that both DMD and the presence of myocardial fibrosis independently worsen LV rotational mechanics.In Chapter 5 we report on the effects of conventional cardiac MRI exams, which require repeated breath holding and place a burden on some clinical patients, on measure of LV rotational mechani

This chapter discusses the recent progress in echocardiography, nuclear imaging techniques, CMR, and CT in characterizing patients with acute myocardial infarct. It will expose the pathophysiology of acute infarcts and the principles by which non-invasive imaging techniques allow the identification of different characteristics of infarcted myocardium such as necrosis, area at risk, microvascular obstruction, edema, hemorrhage, and altered metabolism and innervation. Next, it will discuss the clinical role of the different imaging techniques in patients with infarct and, in particular, for diagnosis of acute infarct, detection of acute and chronic complications, post-infarct remodeling, prediction of prognosis, identification of high risk patients, and selection of device and revascularization therapy. Finally, we attempt to provide an outlook on new and upcoming developments in infarct imaging for each of the respective imaging techniques.

Cardiac magnetic resonance imaging (MRI) is a proven technique for the evaluation of myocardial structure and function. An introduction to cardiac physiology is presented in Chapter 1, wherein a measure of LV rotational mechanics called LV twist is defined. LV twist is the apparent rotation of the LV apex relative to the LV base and provides insight into LV function beyond that traditionally reported in measures like ejection fraction. Importantly, cardiac MRI techniques are very well suited to evaluating cardiac structure and function and these methods are outlined in Chapter 2. In particular, MRI tagging can be used to non-invasively generate myocardial tissue landmarks that facilitate the qualitative and quantitative assessment of left ventricular (LV) myocardial deformation in both research and clinical settings. This thesis focuses on several developments. First, we developed a new tagging technique called complementary radial tagging (CRT) that generates a tagging pattern that better matches the annular shaped LV myocardium in the short-axis view. CRT also has better tag contrast during late diastolic phases and can be used to accurately measure the LV mechanics during all cardiac phases (Chapter 3). In parallel with the development of the CRT technique we used conventional clinical tagging protocols to measure LV rotational mechanics quantitatively. Myocardial fibrosis is known to frequently occur in patients with Duchenne Muscular Dystrophy (DMD). The consequences of myocardial fibrosis on LV mechanics, however, are incompletely understood. In Chapter 4 we report on the LV rotational mechanics in patients with DMD with or without myocardial fibrosis. The results suggested that both DMD and the presence of myocardial fibrosis independently worsen LV rotational mechanics.In Chapter 5 we report on the effects of conventional cardiac MRI exams, which require repeated breath holding and place a burden on some clinical patients, on measure of LV rotational mechani

OBJECTIVE: To assess whether magnetic resonance imaging could detect any cardiac morphological or functional myocardial alterations in healthy children and young adults with ventricular arrhythmias. METHODS: Twenty-three subjects (14 male, mean age 15.6 +/- 6.5 years) with frequent (> or =30/h) premature ventricular complexes (PVCs) on Holter monitoring and normal echocardiographic and electrocardiographic findings underwent cardiac magnetic resonance (CMR) on a 1.5T scanner and an exercise stress test. Subjects were also followed up for a period of 71 +/- 24 months. RESULTS: CMR showed no evidence of structural cardiac abnormalities, but functional assessment revealed significant impairment in 17 subjects (74%): mild to moderate right ventricular enlargement was found in all of these subjects associated with a mild reduction of ventricular function in five cases (22%) and mild free wall and/or apex contraction abnormalities in eight subjects (35%). PVCs persisted during stress test in three subjects (13%) and disappeared in 19 (83%). No serious cardiac event was observed during the follow-up. CONCLUSIONS: Our study shows that subjects with PVCs without detectable electrocardiographic and echocardiographic abnormalities frequently exhibit functional impairment of the right ventricle at CMR, potentially responsible for ventricular arrhythmias. Although the causes of these abnormalities remain to be elucidated, the long-term outcome of these subjects is excellent.

This note describes a dataset consisting of 14 annotated cardiac MR images. Points of correspondence are placed on each image at the left ventricle (LV). As such, the dataset can be readily used for building statistical models of shape. Further, format specifications and terms of use are given.

Kvantifikace T1 mapy myokardu je důležité pro diagnostiku myokardické fibrózy. Kardiální magnetická rezonance malých zvířat je obtížná z důvodu vysoké srdeční a respirační frekvence. Pulsní sekvence navržené v této práci jsou typu IR FLASH a Intragate FLASH. Sekvence IR FLASH byla porovnána s referenční sekvencí RARE na statickém fantomu. Obě sekvence byly aplikovány během měření myokardu potkana. Pro kvantifikaci T1 byl vyvinut software v prostředí Matlab. Pomocí tohoto softwaru byly vyhodnoceny T1 mapy myokardu potkana., T1 mapping of myocardial tissue is important for diagnostics of myocardial fibrosis. Cardiac magnetic resonance imaging of small animals is challenging due to high heart and respiratory rates. Pulse sequences for T1 mapping are proposed in this thesis based on inversion recovery FLASH and Intragate FLASH. The sequence IR FLASH was compared to the reference sequence RARE on a static phantom. Both sequences were applied for measuring the myocardium of a rat. For T1 quantification a software in Matlab was developed. Using this software, T1 maps of rat myocardium were calculated.

Kvantifikace T1 mapy myokardu je důležité pro diagnostiku myokardické fibrózy. Kardiální magnetická rezonance malých zvířat je obtížná z důvodu vysoké srdeční a respirační frekvence. Pulsní sekvence navržené v této práci jsou typu IR FLASH a Intragate FLASH. Sekvence IR FLASH byla porovnána s referenční sekvencí RARE na statickém fantomu. Obě sekvence byly aplikovány během měření myokardu potkana. Pro kvantifikaci T1 byl vyvinut software v prostředí Matlab. Pomocí tohoto softwaru byly vyhodnoceny T1 mapy myokardu potkana., T1 mapping of myocardial tissue is important for diagnostics of myocardial fibrosis. Cardiac magnetic resonance imaging of small animals is challenging due to high heart and respiratory rates. Pulse sequences for T1 mapping are proposed in this thesis based on inversion recovery FLASH and Intragate FLASH. The sequence IR FLASH was compared to the reference sequence RARE on a static phantom. Both sequences were applied for measuring the myocardium of a rat. For T1 quantification a software in Matlab was developed. Using this software, T1 maps of rat myocardium were calculated.

Kvantifikace T1 mapy myokardu je důležité pro diagnostiku myokardické fibrózy. Kardiální magnetická rezonance malých zvířat je obtížná z důvodu vysoké srdeční a respirační frekvence. Pulsní sekvence navržené v této práci jsou typu IR FLASH a Intragate FLASH. Sekvence IR FLASH byla porovnána s referenční sekvencí RARE na statickém fantomu. Obě sekvence byly aplikovány během měření myokardu potkana. Pro kvantifikaci T1 byl vyvinut software v prostředí Matlab. Pomocí tohoto softwaru byly vyhodnoceny T1 mapy myokardu potkana., T1 mapping of myocardial tissue is important for diagnostics of myocardial fibrosis. Cardiac magnetic resonance imaging of small animals is challenging due to high heart and respiratory rates. Pulse sequences for T1 mapping are proposed in this thesis based on inversion recovery FLASH and Intragate FLASH. The sequence IR FLASH was compared to the reference sequence RARE on a static phantom. Both sequences were applied for measuring the myocardium of a rat. For T1 quantification a software in Matlab was developed. Using this software, T1 maps of rat myocardium were calculated.

Kvantifikace T1 mapy myokardu je důležité pro diagnostiku myokardické fibrózy. Kardiální magnetická rezonance malých zvířat je obtížná z důvodu vysoké srdeční a respirační frekvence. Pulsní sekvence navržené v této práci jsou typu IR FLASH a Intragate FLASH. Sekvence IR FLASH byla porovnána s referenční sekvencí RARE na statickém fantomu. Obě sekvence byly aplikovány během měření myokardu potkana. Pro kvantifikaci T1 byl vyvinut software v prostředí Matlab. Pomocí tohoto softwaru byly vyhodnoceny T1 mapy myokardu potkana., T1 mapping of myocardial tissue is important for diagnostics of myocardial fibrosis. Cardiac magnetic resonance imaging of small animals is challenging due to high heart and respiratory rates. Pulse sequences for T1 mapping are proposed in this thesis based on inversion recovery FLASH and Intragate FLASH. The sequence IR FLASH was compared to the reference sequence RARE on a static phantom. Both sequences were applied for measuring the myocardium of a rat. For T1 quantification a software in Matlab was developed. Using this software, T1 maps of rat myocardium were calculated.

Kvantifikace T1 mapy myokardu je důležité pro diagnostiku myokardické fibrózy. Kardiální magnetická rezonance malých zvířat je obtížná z důvodu vysoké srdeční a respirační frekvence. Pulsní sekvence navržené v této práci jsou typu IR FLASH a Intragate FLASH. Sekvence IR FLASH byla porovnána s referenční sekvencí RARE na statickém fantomu. Obě sekvence byly aplikovány během měření myokardu potkana. Pro kvantifikaci T1 byl vyvinut software v prostředí Matlab. Pomocí tohoto softwaru byly vyhodnoceny T1 mapy myokardu potkana., T1 mapping of myocardial tissue is important for diagnostics of myocardial fibrosis. Cardiac magnetic resonance imaging of small animals is challenging due to high heart and respiratory rates. Pulse sequences for T1 mapping are proposed in this thesis based on inversion recovery FLASH and Intragate FLASH. The sequence IR FLASH was compared to the reference sequence RARE on a static phantom. Both sequences were applied for measuring the myocardium of a rat. For T1 quantification a software in Matlab was developed. Using this software, T1 maps of rat myocardium were calculated.