Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 86-95). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri--Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves : 188-225). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri--Columbia, 1996. / "May 1996" Typescript. Vita. Includes bibliographical references (l. 188-225). Also available on the Internet.

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Submitted in fulfilment of the Master’s Degree in Clinical Technology, Durban University of Technology, 2012. / The sirolimus-eluting stent (Cypher) was the first approved drug- eluting stent by the Food and Drug Administration in April 2003. This is a stent that is based on a bare-metal stent and is coated with a layer of polymer incorporating sirolimus and releasing it by diffusion. Drug-eluting stents reduced risk of restenosis and repeat revascularization as compared with bare-metal stents. Clinical data has raised concerns that drug-eluting stents are associated with late untoward events. Objectives: The objective of this study was to test the hypothesis that stenting is safe and effective treatment for coronary artery disease. Methods and Results: Sirolimus-eluting stenting was performed in 30 patients with 34 coronary lesions. Detailed clinical follow-up data was collected by personal interview or telephone contact at 1, 6, 12 and 24 months. Patients were followed for 2 years for the occurrence of angina and cardiovascular events namely death, myocardial infarction, stent thrombosis and target lesion revascularization. The mean age of the cohort was 62.33±10.99 years; 83 percent were male, 6 percent were diabetic, 53 percent had hypertension. In spite of the overall patient and lesion complexity there were no incidences of major adverse cardiac events and all patients remained angina free out to two years. Dual antiplatelet therapy with aspirin and plavix varied from at least four weeks to one year. One patient had a bleeding event. Conclusions: Treatment of lesions with sirolimus-eluting stents is associated with a sustained clinical benefit two years after device implantation.

Throughout the development of computed tomographic (CT) imaging the challenges of capturing the heart, with its perpetual, vigorous motion, and in particular the tiny detail within the coronary arteries, has driven technological progress. Today, CT is a widely used and rapidly growing modality for the investigation of coronary artery disease, as well as other cardiac pathology. However, limitations remain and particular patient groups present a significant challenge to the CT operator. This thesis adds new knowledge to the assessment of these difficult-to-image patients. It considers patients with artefact from coronary artery calcification or stents, examining the remarkable diagnostic performance of high definition scanning, as well as material subtraction techniques using dual energy CT, alongside ways in which current technology might be revisited and refined with the use of alternative image reconstruction methods. Patients with challenging heart rate or rhythm abnormalities are considered in three studies; how to achieve diagnostic image quality in atrial fibrillation, the safety of an aggressive approach to intravenous beta-blocker use prior to coronary imaging, and the development of patient information to address anxiety as a source of tachycardia and motion artefact. Finally, the novel application of a single source, dual energy CT scanner to additional cardiac information is considered, with studies of myocardial perfusion CT and delayed iodine enhancement imaging, to identify ways in which non-coronary imaging might be exploited to more thoroughly evaluate a patient’s coronary artery status. These findings are presented in the context of developing technology and together offer a range of potential options for operators of cardiac CT when faced with a difficult-to-image patient.

Background: Smoking continues to be the leading cause of preventable disease, disability and death in the United States attributing to more than 480,000 deaths every year. An estimated 36.5 million US adults (15% of US population) currently smoke, and more than 16 million live with a smoking-related disease. Since recent years, there has been a surge of alternate tobacco products in the US markets, and one such product that has gained importance was electronic cigarettes. Studies have demonstrated a rapid increase in e-cigarette use among US adults. However, research is limited on the effects of e-cigarette on human health. Thus, using a nationally representative sample of US adults, we investigated the association of e-cigarette use with coronary heart disease (CHD) among adults aged ≥18-years in the US. Methods: Data from the 2016 Behavioral Risk Factor Surveillance System (BRFSS) were used to conduct this study. BRFSS is a cross-sectional survey administered to 486,303 adults in all 50 states to collect information about their health-related risk behaviors, chronic health conditions and the use of preventive services. Participants’ self-reported responses were used to define study outcome (CHD), exposure (current e-cigarette use) and covariates (demographics [sex and race], behaviors [cigarette smoking, alcohol consumption, marijuana use, physical activity], and physical conditions [overweight or obesity]). Multiple logistic regression analysis was conducted to determine the association between e-cigarette use and CHD. Adjusted odds ratio and corresponding 95% confidence intervals were presented. Results: Approximately 6.19% of US adults reported CHD events and 3.1% of US adults were current e-cigarette users. Approximately 5.42% of e-cigarette smoking US adults reported CHD outcomes in 2016. Overall, the odds of CHD events was 34.9% less among e-cigarette users than those who were not e-cigarette users (adjusted odds ratio (aOR): 0.65, 95% confidence interval (CI): 0.60-0.70, p Conclusion: The study found out that e-cigarette user was less likely associated with CHD outcomes in US adults. Given the limitations of cross-sectional study nature and self-reported bias of responses, longitudinal studies with objective measures are needed to further investigate the association between e-cigarette use and CHD.

INTRODUCTION: Congenital Heart Defects are the most common congenital defects in the United States. They affect a significant proportion of all births, and many babies with CCHDs are not expected to survive their first year. While diagnostic and surgical interventions have drastically improved mortality rates, a growing population of adolescent and adult CHD patients continue to face unique developmental, psychological and QoL issues. METHODS: Medical journal articles were utilized to determine the prevalence, mortality rates, survival rates, adverse psychological outcomes, and follow-up rates for CHD patients as they transitioned through adolescence. Most articles came from Pediatrics, The Journal of Pediatrics, and Circulation. RESULTS: From 1980-2005, the prevalence of CHDs in the United States increased, while CHD mortality decreased by nearly half. Over a similar time period, CHD patients were more likely to have poor psychological, behavioral, and QoL outcomes than their healthy peers. Specifically, CHD patients were likely to have developmental disorders, lower QoL, and loss to follow-up when transitioning to adult care providers. CHD patients also demonstrated a poor understanding of their condition, especially with respect to need for follow-up, identifying symptoms of deteriorating heart condition, and the negative effects of smoking, drugs, and alcohol. DISCUSSION: Diagnostic and surgical interventions for CHD patients have led to increased survival. However, many of these interventions occur in the early stages of life, leaving a gap in medical management of CHD patients as they transition through adolescence. This is represented by high attrition rates for those following-up with adult care providers, adverse psychosocial outcomes, and patients’ lack of knowledge about their condition. CHD patients may benefit from more comprehensive, coordinated and formal transition programs that incorporate good social support systems, self-efficacy, and education about their condition.