Asher, InnesWilson, NigelWebb, Rachel2020-11-022020-11-022019http://hdl.handle.net/2292/53433Background Acute rheumatic fever and its sequela chronic rheumatic heart disease result from a dysregulated immune response to group A streptococcal pharyngitis. In New Zealand, acute rheumatic fever rates in children of Māori and Pacific ethnicity are amongst the highest in the world. The epidemiology of acute rheumatic fever is well-understood, due to national-level surveillance and rheumatic fever registers maintained by District Health Boards. However there are many knowledge gaps surrounding the epidemiology and impact of chronic rheumatic heart disease. Rheumatic heart disease prevalence is not nationally monitored, it may occur in individuals who do not report a prior history of acute rheumatic fever, and typically it causes no symptoms unless advanced valvular heart disease is present. Echocardiography may enable rheumatic heart disease to be detected at an earlier stage. Methods A focused literature review was undertaken to describe the disease spectrum of rheumatic fever and chronic rheumatic heart disease, and approaches to clinical management, prevention and control. The epidemiology of rheumatic fever and rheumatic heart disease in New Zealand was reviewed and assessed in two parts, namely, up until 2010, and the current decade from 2011 onwards. Original investigations were undertaken to determine the prevalence of rheumatic heart disease in high-risk New Zealand populations using portable echocardiography. Additional studies were undertaken to derive normative echocardiographic data from high and low risk populations to refine echocardiographic diagnostic criteria for rheumatic heart disease. Further investigations were conducted to investigate selected clinical outcomes of rheumatic heart disease in children, in particular the morbidity and mortality associated with heart valve surgery, and the role of rheumatic heart disease as a predisposing factor infective endocarditis. Results In New Zealand, high rates of rheumatic fever amongst Māori and Pacific peoples have persisted for several decades and there are now widening ethnic disparities, with highest rates observed amongst Pacific peoples living in South Auckland. Original studies determined echocardiographic rheumatic heart disease prevalence of 2.6% in children of Māori and Pacific ethnicity but in a population of almost 400 children from a low-incidence rheumatic fever region, no child had evidence of rheumatic heart disease. Using World Heart Federation Criteria, prevalence among young adults was 2.2% and prevalence in first degree relatives over iii twice the background population rates. Surgery for rheumatic heart disease was associated with high rates of complications and mortality, however morbidity and mortality was lower in those who underwent mitral valve repair as compared to mechanical valve replacement. Rheumatic heart disease is a predisposing factor for infective endocarditis in approximately 13% of New Zealand childhood endocarditis cases. Conclusions Echocardiography detected a substantial burden of previously undiagnosed rheumatic heart disease in children and adults from high-incidence rheumatic fever populations in New Zealand. This, together with high morbidity and mortality associated with severe rheumatic heart disease, underscores the importance of focusing on rheumatic heart disease in addition to acute rheumatic fever in prevention and control efforts. These findings have contributed to an ongoing programme of local and international research to determine the utility of echocardiography as a tool for rheumatic heart disease case detection and control in high-risk populations.Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated.Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated.https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htmThesis2020-09-21Copyright: The authorhttp://purl.org/eprint/accessRights/OpenAccessQ112950800