The cardiovascular manifestations of human immunodeficiency virus infection and the acquired immunodeficiency syndrome : prevalence, prognosis and pathogenesis
The main aim of the work presented in this thesis was to delineate the natural history and pathogenesis of HIV related heart muscle disease. Additional studies examined the influence of HIV infection on the risk and course of infective endocarditis. Two hundred and ninety-six HIV positive adults were examined by echocardiography in a four year prospective study. Abnormal cardiac function was identified in 14.8%. Dilated cardiomyopathy was present in 4.4% borderline left ventricular dysfunction in 6.4% and isolated right ventricular dysfunction in 4%. Dilated cardiomyopathy was strongly associated with reduced survival compared to those with normal hearts (median survival from diagnosis 101 days, compared to 472 days for those with structurally normal hearts). A newly developed ELISA for anti α-myosin autoantibodies revealed abnormal results in 43% of patients with HIV heart muscle disease, 19% of HIV positive patients with normal hearts and 3% of HIV negative controls. Cardiac specific autoantibodies were also more common in HIV positive patients. Autoimmunity may therefore be important in the pathogenesis of HIV related heart muscle disease. There were no significant socio-economic differences between the HIV positive patients with and without heart disease or the lifestyle matched HIV negative controls studied but mean serum selenium was 33% lower in the HIV positive individuals. Similar differences in toenail (15% lower) and myocardial (17% lower) levels and glutathione peroxidase (15% lower) were also found, but there were no specific differences between patients with and without cardiac abnormalities. Mean α- and γ- tocopherol and α- and β- carotene levels were significantly reduced in our HIV positive patient group, compared to the local HIV negative population, but similar differences existed in a socio-economically matched group of HIV negative drug users. Intravenous drug use was the most important risk factor for the development of the condition.