Diss. (sammanfattning) Uppsala : Univ., 2001. / Härtill 4 uppsatser.

Thesis (M. Phil.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 146-185).

Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 109-117).

Thesis (M.S.)--University of Alabama at Birmingham, 2007. / Description based on contents viewed Oct. 5, 2007; title from title screen. Includes bibliographical references (p. 19-20).

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Background: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, with a higher incidence in older adults (Iwasaki, Nishida, Kato,& Nattel, 2011). There are limited data regarding AF care for adults in rural communities with AF. Purpose: The purpose of this study was to determine whether patients in a rural community hospital received AF care based on American Heart Association (AHA) Get with the Guidelines-Atrial Fibrillation (GWTG-AF) standardized guidelines and whether use of these guidelines was associated with improved thirty day outcomes. Methods: A retrospective medical records review was used. Medical records of patients with AF as primary or secondary diagnoses in inpatient or emergency department admissions were reviewed to determine whether AF guideline care was provided during the hospital stay. AHA GWTG-AF was used to evaluate guideline based care (January, et al., 2014). Results: The results from this study showed that while quality care is provided to rural patients with AF, standardized guideline care is not consistently provided. Preventative care, such as use of angiotensin converting enzyme inhibitors (ACE-I) or angiotensin receptor blockers (ARB) was only provided for 50% of patients who required it. Evaluation of thromboembolism risk was not consistently provided for AF patients. Use of the congestive heart failure, hypertension, age, diabetes, stroke, vascular disease, age, sex category (CHADS₂/CHA₂DS₂VASc) score was not used in the emergency department or observation units (ED/OBS) and limited use of CHADS₂/CHA₂DS₂VASc score was shown in the inpatient environment, with only 19.5% of patients receiving assessment of thromboembolism risk. Bleeding risk was not documented by clinicians, such as the hypertension, abnormal renal/liver function, stroke bleeding predisposition, labile INR, elderly, drugs/alcohol (HAS-BLED) score. Thromboembolism medications were administered to 156 (78%) of the patients without documentation of these risk factors. Rate control strategies were used more frequently than rhythm control strategies (76% compared to 15%). There were three readmissions for minor bleeding during the pre-selected readmission window, and did not exhibit enough data to generalize whether immediate 30 day outcomes are affected by adherence to guideline care. Conclusions: While some of the GWTG-AF guidelines are followed for AF patients in this rural environment, there are significant areas where adherence to the guidelines is limited. Use of preventative care measures, thromboembolism risk, bleeding risk, and appropriate anticoagulation administration for patients at risk were areas that did not have adequate guideline adherence. Future research is needed to evaluate what barriers may exist to using guideline based care. Such research can also serve as the basis for education programs for clinicians to increase adherence to guideline care. In addition, future research may include a longer readmission period to evaluate for improved outcomes.

O objeto de estudo são os eventos cardíacos resultantes da infusão contínua de cloridrato de amiodarona em pacientes que evoluíram com fibrilação atrial em pós-operatório de cirurgia cardíaca. Os objetivos foram descrever as características dos pacientes que receberam infusão contínua de cloridrato de amidoarona, apresentar a prevalência de bradicardia e hipotensão encontrada nos pacientes que receberam infusão contínua de cloridrato de amiodarona e discutir as implicações dos achados para a prática dos enfermeiros a partir da prevalência encontrada de bradicardia e hipotensão decorrente da infusão contínua desta substância. Trata-se de um estudo transversal, retrospectivo, documental, por meio de análise de prontuários e avaliação quantitativa dos mesmos. Desenvolvida em uma unidade de pós-operatório de cirurgia cardíaca em um hospital universitário pertencente à rede sentinela no município do Rio de Janeiro. Foi considerado hipotensão em presença de PAS menor que 90 mmHg e bradicardia em presença de frequência cardíaca menor que 60 bpm. As variáveis que caracterizavam a população do estudo e as aferições de pressão arterial e frequência cardíaca foram transcritas para um instrumento de coleta de dados dos anos de 2010 e 2011, gerando 1782 horas de infusão contínua de cloridrato de amiodarona em 27 pacientes cirúrgicos (10,50%). Tratou-se de uma população predominantemente feminina, com idade a cima de 60 anos, período de internação superior a uma semana, apresentava hipertensão arterial prévia (59,26%), era portadora de fibrilação atrial (55,56%) e o diagnóstico cirúrgico de revascularização do miocárdio com circulação extracorpórea foi predominante (70,37%). Os dados mostram que 85,19% dos pacientes eram portadores de pelo menos um fator de risco, 70,37% apresentavam dois fatores de risco e 55,55% apresentavam três fatores de risco para desenvolver fibrilação atrial no pós-operatório de cirurgia cardíaca. Foi encontrada uma prevalência de 85,19% pacientes que apresentaram bradicardia, 66,67% apresentaram hipotensão e 59,26% apresentaram tanto bradicardia como hipotensão. Foram 160 episódios de bradicardia com 6,40 episódios por paciente e 77 episódios de hipotensão com 4,2 por paciente. A bradicardia ocorreu principalmente entre 48 e 72 horas do inicio da infusão. Já a hipotensão aumentou progressivamente nas primeiras 48 horas de infusão. Na presença de bradicardia a intervenção mais frequente foi redução da vazão de amiodarona já na presença de hipotensão, a manutenção de infusão de noradrenalina foi a conduta mais regular. Como estratégia de melhoria para segurança do paciente, foram elaboradas condutas como método de barreira para prevenção de eventos adversos como a bradicardia e hipotensão. Os principais cuidados de enfermagem a serem implementados pelo enfermeiro foram o levantamento de fatores de risco para a fibrilação atrial, a detecção da fibrilação atrial, a manutenção de monitorização cardíaca contínua, aferição horária do ritmo cardíaco e o controle da frequência cardíaca e pressão arterial, objetivando intervir precocemente em presença de hipotensão ou bradicardia. / The subject-matter of the following study is the cardiac events that are consequences from the continuous infusion of amiodarone hydrochloride into patients that developed atrial fibrillation in a postoperative care from a cardiac surgery. The aims of the study are: to describe the characteristics of the patients that received continuous infusion of amiodarone hydrochloride; to present the prevalence of bradycardia and hypotension in the patients that received continuous infusion of amiodarone hydrochloride; and to discuss the implications of the findings for the practice of nurses from the prevalence of bradycardia and hypotension that stemmed from the continuous infusion of amiodarone hydrochloride. This is a cross-sectional, retrospective, documentary study through the analysis and quantitative evaluation of medical records. It was developed in a cardiac surgery postoperative unit in a university hospital that belongs to the Rede Sentinela in the City of Rio de Janeiro. Hypotension was defined as the presence of a systemic arterial blood pressure (ABP) lower than 90 mmHg and bradycardia as the presence of a heart rate below 60 bpm. The variables that characterized the population of the study and the measuring of arterial blood pressure and heart rate were transcribed into a data collection instrument through the years 2010 and 2011, creating 1782 hours of continuous infusion of amiodarone hydrochloride into 27 surgical patients (10,50%). The population of the study was mainly composed of women over 60 years old, with an admission over a week period, they showed pre-existing arterial hypertension (58,26%) and have atrial fibrillation (55,56%) and the surgical diagnosis of myocardium revascularization with extracorporeal circulation was predominant (70,37%). The data showed that 85,19% of the patients were carriers of at least one risk factor, 70,37% showed two risk factors and 55,55% showed three risk factors to develop atrial fibrillation in the postoperative of a cardiac surgery. It was found a predominance of 85,19% patients that showed bradycardia, 66,67% showed hypotension and 59,29% showed bradycardia as well as hypotension. There were 160 bradycardia episodes in a rate of 6,40 episodes per patients and 77 hypotension in a rate of 4,2 episodes per patients. The bradycardia happened mainly between the 48 and 72 hours after the infusion. Now, the hypotension increased progressively in the first 48 hours after the infusion. In the presence of bradycardia the medical intervention most frequent was the reduction of the amiodarone flow rate, while in the presence of hypotension the continuity of the norepinephrine infusion was the most common conduct. As strategy to improve the patient safety, conducts were devised as barrier method to prevent adverse events such as the bradycardia and hypotension. The main nursing care implemented by the nurse were the survey of risk factors to the atrial fibrillation, the detection of atrial fibrillation, the continuity of the continuous cardiac monitoring, hourly measuring of the heart rate and the control of the heart rate and arterial blood pressure, in order for a earlier medical intervention in the presence of hypotension or bradycardia.

O objeto de estudo são os eventos cardíacos resultantes da infusão contínua de cloridrato de amiodarona em pacientes que evoluíram com fibrilação atrial em pós-operatório de cirurgia cardíaca. Os objetivos foram descrever as características dos pacientes que receberam infusão contínua de cloridrato de amidoarona, apresentar a prevalência de bradicardia e hipotensão encontrada nos pacientes que receberam infusão contínua de cloridrato de amiodarona e discutir as implicações dos achados para a prática dos enfermeiros a partir da prevalência encontrada de bradicardia e hipotensão decorrente da infusão contínua desta substância. Trata-se de um estudo transversal, retrospectivo, documental, por meio de análise de prontuários e avaliação quantitativa dos mesmos. Desenvolvida em uma unidade de pós-operatório de cirurgia cardíaca em um hospital universitário pertencente à rede sentinela no município do Rio de Janeiro. Foi considerado hipotensão em presença de PAS menor que 90 mmHg e bradicardia em presença de frequência cardíaca menor que 60 bpm. As variáveis que caracterizavam a população do estudo e as aferições de pressão arterial e frequência cardíaca foram transcritas para um instrumento de coleta de dados dos anos de 2010 e 2011, gerando 1782 horas de infusão contínua de cloridrato de amiodarona em 27 pacientes cirúrgicos (10,50%). Tratou-se de uma população predominantemente feminina, com idade a cima de 60 anos, período de internação superior a uma semana, apresentava hipertensão arterial prévia (59,26%), era portadora de fibrilação atrial (55,56%) e o diagnóstico cirúrgico de revascularização do miocárdio com circulação extracorpórea foi predominante (70,37%). Os dados mostram que 85,19% dos pacientes eram portadores de pelo menos um fator de risco, 70,37% apresentavam dois fatores de risco e 55,55% apresentavam três fatores de risco para desenvolver fibrilação atrial no pós-operatório de cirurgia cardíaca. Foi encontrada uma prevalência de 85,19% pacientes que apresentaram bradicardia, 66,67% apresentaram hipotensão e 59,26% apresentaram tanto bradicardia como hipotensão. Foram 160 episódios de bradicardia com 6,40 episódios por paciente e 77 episódios de hipotensão com 4,2 por paciente. A bradicardia ocorreu principalmente entre 48 e 72 horas do inicio da infusão. Já a hipotensão aumentou progressivamente nas primeiras 48 horas de infusão. Na presença de bradicardia a intervenção mais frequente foi redução da vazão de amiodarona já na presença de hipotensão, a manutenção de infusão de noradrenalina foi a conduta mais regular. Como estratégia de melhoria para segurança do paciente, foram elaboradas condutas como método de barreira para prevenção de eventos adversos como a bradicardia e hipotensão. Os principais cuidados de enfermagem a serem implementados pelo enfermeiro foram o levantamento de fatores de risco para a fibrilação atrial, a detecção da fibrilação atrial, a manutenção de monitorização cardíaca contínua, aferição horária do ritmo cardíaco e o controle da frequência cardíaca e pressão arterial, objetivando intervir precocemente em presença de hipotensão ou bradicardia. / The subject-matter of the following study is the cardiac events that are consequences from the continuous infusion of amiodarone hydrochloride into patients that developed atrial fibrillation in a postoperative care from a cardiac surgery. The aims of the study are: to describe the characteristics of the patients that received continuous infusion of amiodarone hydrochloride; to present the prevalence of bradycardia and hypotension in the patients that received continuous infusion of amiodarone hydrochloride; and to discuss the implications of the findings for the practice of nurses from the prevalence of bradycardia and hypotension that stemmed from the continuous infusion of amiodarone hydrochloride. This is a cross-sectional, retrospective, documentary study through the analysis and quantitative evaluation of medical records. It was developed in a cardiac surgery postoperative unit in a university hospital that belongs to the Rede Sentinela in the City of Rio de Janeiro. Hypotension was defined as the presence of a systemic arterial blood pressure (ABP) lower than 90 mmHg and bradycardia as the presence of a heart rate below 60 bpm. The variables that characterized the population of the study and the measuring of arterial blood pressure and heart rate were transcribed into a data collection instrument through the years 2010 and 2011, creating 1782 hours of continuous infusion of amiodarone hydrochloride into 27 surgical patients (10,50%). The population of the study was mainly composed of women over 60 years old, with an admission over a week period, they showed pre-existing arterial hypertension (58,26%) and have atrial fibrillation (55,56%) and the surgical diagnosis of myocardium revascularization with extracorporeal circulation was predominant (70,37%). The data showed that 85,19% of the patients were carriers of at least one risk factor, 70,37% showed two risk factors and 55,55% showed three risk factors to develop atrial fibrillation in the postoperative of a cardiac surgery. It was found a predominance of 85,19% patients that showed bradycardia, 66,67% showed hypotension and 59,29% showed bradycardia as well as hypotension. There were 160 bradycardia episodes in a rate of 6,40 episodes per patients and 77 hypotension in a rate of 4,2 episodes per patients. The bradycardia happened mainly between the 48 and 72 hours after the infusion. Now, the hypotension increased progressively in the first 48 hours after the infusion. In the presence of bradycardia the medical intervention most frequent was the reduction of the amiodarone flow rate, while in the presence of hypotension the continuity of the norepinephrine infusion was the most common conduct. As strategy to improve the patient safety, conducts were devised as barrier method to prevent adverse events such as the bradycardia and hypotension. The main nursing care implemented by the nurse were the survey of risk factors to the atrial fibrillation, the detection of atrial fibrillation, the continuity of the continuous cardiac monitoring, hourly measuring of the heart rate and the control of the heart rate and arterial blood pressure, in order for a earlier medical intervention in the presence of hypotension or bradycardia.

Atrial fibrillation (AF) is the most common sustained arrhythmia and is associated with significant cardiovascular complications, including stroke, myocardial infarction, heart failure, and premature death. The presence of subtle left ventricular (LV) dysfunction is increasingly recognised in patients with AF, raising questions regarding the underlying pathophysiology and potential treatment strategies. I used advanced and multiparametric cardiac magnetic resonance (CMR) methods to investigate potential mechanisms that could contribute to LV dysfunction in patients with AF, controlled ventricular rate and no significant cardiovascular comorbidities (i.e., with so-called 'lone' AF). Patients were evaluated before and after catheter ablation, allowing examination of the effect of restoration of sinus rhythm and reduction in AF burden on LV structure, function, energetics, tissue characteristics, and perfusion. I demonstrated for the first time that patents with lone AF before ablation have significantly impaired ventricular energetics and a subtle reduction in LV systolic function compared to control subjects in sinus rhythm. Furthermore, there was only modest improvement (but not normalisation) in LV function following successful ablation, and myocardial energetics remained impaired despite a significant and sustained reduction in AF burden. These findings imply that lone AF may actually be the consequence (rather than the cause) of an underlying cardiomyopathy. Next, to interrogate advanced ventricular tissue characteristics (such as diffuse myocardial fibrosis) in patients with tachyarrhythmia, I developed a novel CMR method involving a systolic readout T1-mapping sequence. Methodological work in volunteers and patients with tachyarrhythmia demonstrated that this method reports clinically equivalent T1 values to the conventional diastolic readout in healthy volunteers, and was feasible in tachyarrhythmia, producing excellent quality T1 maps. When applied to the investigation of patients with AF, I demonstrated that subtle LV dysfunction in lone AF occurs in the absence of CMR evidence of diffuse myocardial fibrosis, suggesting that LV dysfunction may be reversible with appropriate and targeted therapeutic strategies initiated prior to the development of structural LV remodelling. Finally, I used quantitative perfusion imaging to determine absolute myocardial blood flow and coronary reserve in patients with AF, and determine whether microvascular coronary dysfunction could underlie impaired LV function and energetics in patients with AF. I found that myocardial perfusion is significantly reduced in patients with AF in the absence of significant epicardial coronary artery disease, both at baseline and under conditions of vasodilator stress. Lower baseline blood flow was related to reduced LV performance, and there was no significant change in perfusion after successful AF ablation. These novel findings indicate that coronary microvascular dysfunction may be an important pathophysiological mechanism in lone AF, and at least partially responsible for LV dysfunction. Overall, the findings reported in this thesis have potentially far-reaching implications for the management of patients with AF. They suggest that approaches that predominantly target rhythm control (including anti-arrhythmic medications and ablation) are insufficient to normalise the systemic and cardiometabolic phenotype in patients with AF. Further studies are needed to investigate whether novel approaches that target microvascular and energetic dysfunction in patients with AF can contribute to durable restoration of sinus rhythm and improve clinical outcomes.

INTRODUÇÃO: O aumento da proporção de idosos implica estudar os determinantes dos principais agravos associados ao envelhecimento como a demência, principalmente a associada à doença cerebrovascular. Um fator de risco relevante para doença cerebrovascular é a freqüência de fibrilação atrial crônica. O São Paulo Health and Ageing Study com base populacional para estudo de distúrbio cognitivo e demência é uma oportunidade única para verificar a prevalência de fibrilação atrial e de sua associação com demência. MÉTODOS: Estudo transversal, por arrolamento de 1524 idosos com 65 anos ou mais estudo acima, no distrito do Butantã, cidade de São Paulo. O diagnóstico de fibrilação atrial foi feito com o eletrocardiograma de repouso de doze derivações e o de demência foi feito utilizando-se o protocolo do Research Group of Dementia 10/66. Estudaram-se variáveis sócio-econômicas e fatores de risco cardiovascular como hipertensão, diabetes, dislipidemia e obesidade. RESULTADOS: A amostra estudada tinha idade média de 72,2 anos, era predominantemente feminina, branca, casada, de baixa escolaridade e renda. A prevalência de fibrilação atrial associou-se ao aumento da idade e foi de 1,9% para o sexo feminino e 3,1% para o sexo masculino, com prevalência para ambos os sexos ajustada para idade de 2,7%. A prevalência de demência também se associou ao aumento da idade e sua prevalência idade ajustada foi de 4,9%, maior em mulheres (4,8%) do que em homens (3,6%). A razão de chances ajustada para idade para a associação de fibrilação atrial e demência foi de 2,88 (Intervalo de Confiança, IC 95% - 0,98 8,40) para ambos os sexos sendo e, de 1,50 (IC95% - 0,19 11,83) para homens e 4,48 (IC95% - 1,23 16,29) para mulheres. Encontrou-se maior risco de demência entre mulheres com fibrilação atrial (17,7%) do que entre os participantes do mesmo sexo sem demência (4,6%) Outras alterações no eletrocardiograma de repouso com interesse foram determinadas como com área inativa (código de Minnesotta q1- q2) de: 9,1% nas mulheres e 16,6% nos homens; e também bloqueio de ramo esquerdo de 3,3%, nas mulheres 3,0% e nos homens 3,6%. CONCLUSÃO: Mulheres idosas com fibrilação atrial têm diagnóstico de demência quase quatro vezes mais do que aquelas em ritmo sinusal / INTRODUCTION: The growing aging population proportion makes us study the most important illness related with aging of the population as dementia, specially the dementia associated to stroke. Atrial fibrillation is a main risk factor with cerebrovascular disease. The São Paulo Heath and Ageing Study a population based study for cognitive disturb and dementia is an unique opportunity to verify the atrial fibrillation prevalence and its association with dementia. Methods: This is a cross-sectional study. The population of this study was composed by 1,524 elderly people, over 65 years of age, covered by the Health Program Family in the Butantã district, São Paulo, who were recruited door by door. The diagnosis of atrial fibrillation was made using a twelve lead resting electrocardiogram and the diagnosis of dementia was made by the protocol of Research Group of Dementia 10/66. We studied socio economic variables and cardiovascular risk factors as hypertension, diabetes, dislipidemia and obesity. RESULTS: The studied population had a mean age of 72.2 years old and was predominantly female, white, married and of low educational and financial status. We found that atrial fibrillation prevalence increased throughout age-strata and was of 1.9% among the females and 3.1% among the males, and age-adjusted prevalence of 2.7%. The prevalence of dementia also increases with age and its ageadjusted prevalence was of 4.9%, greater among the females (4.8%) than among the males (3.6%). The odds ratio age-adjusted for the association of atrial fibrillations and dementia was of 2.88 (Confidence interval, 95% CI 0.98 8.40) for both sex: 1.50 among men (95% CI 0.19 11.83), and 4.48 among women (95% CI 1.23 16.29). We found a higher risk of dementia among the female with atrial fibrillation (17.7%) than among female participants without atrial fibrillation (4.6%). Other resting electrocardiogram alterations were determined as previous inactive areas (Minnesotta Code q1-q2) of 12.4%: among the females of 9.1% and among the males of 16.6%. The frequency of left bundle-branch block was of 3.3%: among the females of 3.0% and among the males of 3.6% .CONCLUSION: Elderly women with atrial fibrillation had the diagnosis of dementia almost four times greater than that of women with sinus rhythm