The diagnostic and prognostic value of cardiovascular magnetic resonance imaging in heart failure

Abstract

Heart failure (HF) is a highly prevalent clinical syndrome with significant morbidity. There remain several unmet needs in HF, including delayed diagnosis, and knowledge gaps in risk stratification, monitoring of disease progression and determining response to treatment. Cardiovascular magnetic resonance imaging (CMR) has become the non-invasive reference standard for evaluating HF due to its ability to accurately assess cardiac volumes, function, and myocardial tissue characteristics. As a result, CMR imaging in HF has been endorsed in multiple HF guidelines. The aim of this thesis was to investigate whether novel CMR techniques could improve upon current diagnostic algorithms, provide accurate risk stratification in HF and assess response to treatment. Chapter 2 reports on the study of a novel CMR sequence to quantify lung water density (LWD) in patients at risk of HF and in healthy volunteers. LWD was increased in patients at risk of heart failure from healthy volunteers, indicating a potential role for CMR in the early diagnosis of HF. Chapter 3 reports on the findings of a CMR study in a large cohort of patients with hypertensive heart disease, which showed that markers of focal and diffuse myocardial fibrosis predict cardiovascular outcomes in this group. Chapter 4 reports on the findings of a CMR and biomarkers study in patients with HF and DM, which showed that CMR-derived global longitudinal strain and soluble suppression of tumorigenicity 2 (sST2), a novel HF biomarker, are prognostic in this group. Finally, chapter 5 reports on the findings of a longitudinal CMR study assessing response to treatment in patients with OSA. This study showed that markers of diffuse myocardial fibrosis reduced following treatment. Overall, this thesis highlights the potential for CMR to be better integrated into contemporary HF guidelines, from a role in diagnosis, to risk stratification and prognostication, and assessment of treatment response.