Cardiovascular disease is the leading cause of death in the world. Therefore, there is an increasing need for accurate and efficient cardiovascular risk assessment to optimize cardiovascular... Show moreCardiovascular disease is the leading cause of death in the world. Therefore, there is an increasing need for accurate and efficient cardiovascular risk assessment to optimize cardiovascular treatment. The aorta plays a central role in the cardiovascular system, transporting blood to various organ systems while absorbing the pulsatile pressure of the cardiac output. Aortic stiffness is a marker of vascular aging and has shown to be an independent marker for cardiovascular risk. Additionally, enlarged aortic dimensions are linked to an increased risk of rupture. MRI is capable of providing accurate information on aortic morphology, stiffness and blood flow patterns.In this thesis we expanded the potential clinical utility of MRI-based measures of aortic morphology and function in the assessment of cardiovascular risk and further unravelled complex cardiovascular systemic interactions using MRI. We provided standardized methods and reference values for fundamental MRI-based measures of aortic morphology and function, explored new methods to make PWV more accessible, evaluated the prognostic value of MRI-based measures of aortic morphology and function and explored systemic interactions of cardiovascular function with obesity as well as the brain. These studies contribute to more accurate and accessible cardiovascular risk assessment, which eventually can lead to improved cardiovascular treatment. Show less
Atherosclerotic changes of the carotid artery are associated with elevated cardiovascular risk. Non-invasive imaging studies of the artery can provide information on the presence or absence of... Show moreAtherosclerotic changes of the carotid artery are associated with elevated cardiovascular risk. Non-invasive imaging studies of the artery can provide information on the presence or absence of abnormalities. Although the techniques are extensively used in clinical research their implementation in common practice is not widespread. In this thesis the potential benefits and challenges of carotid imaging in clinical practice are studied. Ultrasound and magnetic resonance imaging are the two modalities of interest. The findings suggest that ultrasound can be performed by the clinician in a routine outpatient setting. Clinicians are able to detect atherosclerotic plaques but not intima-media thickness. Plaques are highly prevalent in asymptomatic primary prevention patients. Magnetic resonance imaging is a new highly reproducible modality but requires further clinical validation. Its utility in individual patient risk assessment is unclear and ultrasound validity cannot be extrapolated to magnetic resonance. The use of a combination of the two imaging modalities may allow for estimation of the lamina adventitia in vivo. Finally, interpretation of the imaging parameters must be done in conjunction with all cardiovascular risk factors and treatment decision should not be based on imaging results alone. Show less
Cardiovascular disease is an important problem in the western world and identification of individuals at risk of cardiovascular disease and identification of patients with cardiovascular disease... Show moreCardiovascular disease is an important problem in the western world and identification of individuals at risk of cardiovascular disease and identification of patients with cardiovascular disease who are at risk of complications is important in order to reduce morbidity and mortality. This thesis shows the potential of MRI for risk stratification in cardiovascular disease. MRI enables assessment of morphology and function of the aortic vessel wall, which is important since the thickness and stiffness of the aortic vessel wall are related with coronary artery disease and cardiovascular events. Furthermore, the potential of MRI for visualization of the coronary arteries and assessment of coronary artery flow is explored. Although, this technique is not yet routinely used, ongoing research may in the future make MRI a valuable technique for detection of coronary artery disease. In addition, it is demonstrated that MRI is an excellent technique for detection and quantification of valve regurgitation. MRI also allows for quantification of scar tissue and contractile reserve in patients with ischemic cardiomyopathy enabling assessment of viability, which is important for optimization of treatment and prognosis. Finally, it is demonstrated that infarct size and infarct tissue heterogeneity measured with MRI are important predictors for long-term survival. Show less