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).

- / -

xvi, 132 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / The Differential Susceptibility Hypothesis and the related Biological Sensitivity to Context theory contend that individuals with "susceptible" traits reap the benefits of positive rearing environments and exhibit better outcomes compared to their less susceptible peers. Studies have largely focused on physiological reactivity as an index of this susceptibility in children and adults, and most have measured physiology by grand mean changes from baseline to a stressor. The goal of this dissertation was to examine baseline Respiratory Sinus Arrhythmia (RSA) and RSA stress reactivity by taking advantage of analytical techniques modeling growth over time, as well as individual differences in this growth-using latent Growth Modeling (LGM) and Growth Mixture Modeling (GMM), respectively. Maternal sensitivity at 5 months and the quality of the attachment environment at 17 months were used as indicators of environmental conditions that might interact with infant susceptibility. Problem behavior and social competence were assessed at 17 months as measures of child well-being. Consistent with the theory of differential susceptibility, there were no significant differences in problem behavior or social competence among infants with low baseline RSA, but infants with high baseline RSA exhibited the lowest levels of problem behavior if reared in an environment that fostered security and more competence if their mothers exhibited greater sensitivity. Contrary to hypotheses, LGM analyses revealed that withdrawal of infant RSA appeared to buffer the impact of being reared in an environment that fostered disorganization, as infants with disorganized attachment histories exhibited the lowest number of problem behaviors. Two distinct groups of children were identified by GMM analyses: a class of infants with low RSA that decreased across the still-face episode, and a class of infants with high RSA that increased across this episode. Class by maternal sensitivity interactions were significantly predictive of social competence, with the high increasing class emerging as the group most susceptible to environmental influences, consistent with the differential susceptibility hypothesis. This dissertation adds importantly to both the sharpening and extension of theories of differential susceptibility. / Committee in charge: Jennifer Ablow, Chairperson, Psychology; Philip Fisher, Member, Psychology; Jeffrey Measelle, Member, Psychology; Jane Squires, Outside Member, Special Education and Clinical Sciences

Theoretical Foundations Catheter ablation is an intervention focused on targeted removal of or damage to an area that causes arrhythmias. This intervention began to be performed at the turn of the 1980s and 1990s because it had been found that treatment with antiarrhythmic drugs was expensive and the drugs had to be taken throughout patients' lives. Thanks to its high success rate and low risk of complications, it has been used in the treatment of supraventricular tachyarrhythmias. At present, the success rate is around 75 %, and the intervention sometimes needs to be repeated to achieve its desired effect. Objectives of the thesis The first objective was to find out whether patients with a history of catheter ablation changed their personal and professional lives. The second objective was to map out which areas of the patients' live were affected most by the catheter ablation treatment. The third objective was to find out about differences in the patients' lives before and after catheter ablation. Research questions V1: In what areas are the patients' lives limited most? V2: What changes have occurred in their lives after catheter ablation? Methodology The research part of the thesis was carried out using a qualitative survey conducted by means of semi-structured interviews with patients suffering from arrhythmias. The total of 9 respondents, 5 males and 4 females, were interviewed. The information obtained was processed using programme Atlas.ti. The results are presented as networks created in this programme. Results The research questions can be answered using the data obtained from the respondents suffering from arrhythmias. The first research question was aimed at finding out in what areas the patients' lives were limited most. It was found out, through the semi-structured interviews, that the most limited area was personal life, in which arrhythmia caused most difficulties to the respondents during sports activities. Because of their health problems, most of the respondents limited their sports activities or abandoned them altogether in favour of their health. Other problems are caused during physical strain and under physical load. That was also the thing that the addressed respondents preferred to avoid. The respondents are also limited in the performance of their work, when the main cause of their problems is psychological stress, mental stress resulting in arrhythmia symptoms in the respective respondents. The second research question examined what changes occurred in their lives after catheter ablation. The changes that occurred related to the care of the family and the household in which they are able to engage in multiple activities. The respondents were able to pay more attention to their families by whom they are encouraged in the treatment. There was an overall improvement in their health, enabling better integration into everyday life. The most frequently mentioned area of changes was sport. During the period after catheter ablation, the respondents began to return gradually to their hobbies. Conclusion The thesis describes the restrictions that arrhythmia caused to the respondents and also the changes that have occurred in the individual respondents after catheter ablation treatment. The results can be used in practice in the education of patients who wait for the catheter ablation treatment and in subsequent measures using the prepared mind maps.

Made available in DSpace on 2014-06-11T19:23:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-11Bitstream added on 2014-06-13T20:11:36Z : No. of bitstreams: 1 mesasocha_jj_me_jabo.pdf: 752821 bytes, checksum: ae9193f72fff8d91a4d5ff5e6d13ac1e (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O N. oleander é uma planta com ampla distribuição mundial, principalmente em regiões tropicais e subtropicais. Esses arbustos são frequentemente usados como plantas ornamentais e possuem mais de 30 glicosídeos cardíacos, causadores do quadro clínico de intoxicação em caninos. O objetivo deste trabalho foi avaliar as alterações clínicas, eletrocardiográficas, bioquímicas, hematológicas e histológicas do rim e avaliar o efeito do uso da frutose 1,6 difosfato e da glicose como alternativas de tratamento em cães intoxicados com 0,25g/Kg de folhas frescas trituradas e adicionadas à ração em única dose. Foram utilizados 10 cães adultos, hígidos, sem raça definida, com 10 a 25Kg de peso, de 4 a 8 anos de idade. Foram distribuídos em dois grupos (Gl e Gll) com 5 animais cada. Para o Gl o tratamento consistiu na administração de uma solução a 10 % de glicose a 50mg/Kg via intravenosa (IV) e em seguida uma infusão continua a 10% de glicose IV por uma hora a 10ml/kg e Gll recebeu frutose 1,6 difosfato, IV a 50mg/Kg, e em seguida uma infusão a 10% da mesma solução, durante uma hora a 10ml/kg. Nenhum dos animais do experimento veio a óbito e todos apresentaram sinais após a intoxicação como: vômito, sialorréia, náuseas, apatia, conjuntiva ocular congesta, desidratação, dor abdominal, tremores, diarréia, inapetência e tenesmo. Observou-se elevação principalmente da GGTU, CK e CKMB. Pela análise do eletrocardiograma encontrou-se arritmias como: bradicardia sinusal, bloqueios atrioventriculares de segundo grau, taquicardia ventricular paroxística e complexos ventriculares prematuros. Na histopatologia não se encontrou alterações no rim. Não observou-se diferença significativa entre tratamentos e na parte clínica houve melhora para Gll observada no consumo de alimento... / N. oleander is a plant with worldwide distribution, mainly in tropical and subtropical regions. These shrubs are frequently used as ornamental plants and have more than 30 cardiac glycosides that can cause poisoning in dogs. The objective of this study was to evaluate alterations in clinical, electrocardiographic, biochemical, hematological parameters, as well as kidney histology, and to evaluate the effect of the use of fructose 1,6 diphosphate and glucose as alternative treatments in dogs poisoned by 0.25 g/kg of fresh ground leaves added to the kibble in a single dose. Ten adult, healthy, mongrel dogs weighing 10 to 25kg and 4 to 8 years old were selected for the study. They were distributed into two groups (GI and GII) of 5 animals each. For GI, treatment consisted of intravenous (IV) administration of 50 mg/kg of a 10% glucose solution followed by continuous IV infusion of 10% glucose at 10 ml/kg for one hour. GII received a solution of fructose 1,6 diphosphate at a dose of 50 mg/kg intravenously followed by infusion of 10 ml/kg of the same 10 % solution for one hour. None of the animals died and all exhibited signs of poisoning as: vomiting, sialorrhea, nausea, apathy, conjunctiva congestion, dehydration, abdominal pain, tremors, diarrhea, loss of appetite and tenesmus. An increase in values of biochemical parameters, especially urinary γ-glutamyl transpeptidase (GGTU), creatinine kinase (CK) and myocardial bound creatinine kinase (CKMB) were mainly. The electrocardiogram revealed arrhythmias such as: sinus bradycardia, second degree atrioventricular block, paroxysmal ventricular tachycardia and ventricular premature complexes. No alterations were found for kidney histology. No significant difference was seen when comparing treatments. Clinically, there was improvement in feed consumption observed for GII ... (Complete abstract click electronic access below)

Abstract Short QT syndrome is an inherited arrhythmia disorder characterized by a short QT interval, typical T-wave and ST-segment morphology and an increased risk of sudden cardiac death. The purpose of this thesis was to study the epidemiology and prognosis of the subjects with short QT intervals. Special attention was paid to the ECG changes that could illustrate the prognosis of subjects with short QT interval. The first study comprised a group of patients with short QT syndrome. We report clinical presentation, ECG morphology, the prevalence of genetic mutations and the results of therapies in this group of patients. The second study population consisted of 10 822 randomly selected middle-aged subjects followed up for 29 ± 10 years. QT intervals were measured using three correction methods for the heart rate in order to assess the prevalence and prognosis of those subjects with short QT intervals. The third population consisted of three patients with short QT syndrome and nine controls. Holter recordings were analyzed to compare transmural dispersion of repolarization between patients and controls and also to study their capability to change repolarization indexes from baseline to maximal values. In the fourth study ECGs from 10 patients with short QT syndrome were compared with ECGs of 12 asymptomatic subjects with short QT intervals. The aim was to find ECG abnormalities that would predict the outcome of the patients. We found 62% of patients to be symptomatic, 34% had cardiac arrest. Atrial fibrillation was common. Most of the patients received an ICD or were placed on hydroquinidine. The prevalence of QTc < 320ms was 0.10% and QTc < 340ms was 0.4%, respectively. Mortality or other serious symptoms did not differ between subjects and controls. We also found that the TPE/QT ratio as an index for abnormal transmural dispersion of repolarization was high compared to controls. Short QT syndrome patients had also lesser capacity to change the QT interval, indicating blunted autonomic response in SQTS. Ten SQTS patients had significantly shorter Jpoint–Tpeak interval and higher TPE/QT ratio compared to controls. In conclusion, shorter than normal QT interval might represent a novel short QT syndrome. However, in the general community short QT interval can reflect only the extreme end of the normal Gaussian distribution of QT intervals and these subjects carry a good prognosis. TPE/QT ratio and Jpoint–Tend intervals can be used as risk stratifiers in subjects with short QT intervals.

No description available.

Acute inhalation of airborne pollutants alters cardiovascular function and has been shown to have its greatest affects on individuals with pre-existing cardiovascular disease. Evidence suggests that pollutant-induced activation of airway sensory nerves via the gating of ion channels is critical to these systemic responses. Here, we have investigated the cardiovascular responses evoked by inhalation of AITC (TRPA1 agonist) and capsaicin (TRPV1 agonist) in healthy Sprague Dawley (SD) and Wistar Kyoto (WKY) rats, and cardiovascular diseased Spontaneously Hypertensive (SH) rats. Inhalation of the agonists by healthy SD and WKY rats caused significant bradycardia, atrio-ventricular (AV) block and prolonged PR-Intervals. Inhalation of TRP agonists caused differential cardiovascular responses in the cardiovascular diseased SH rats, such that the TRP agonists evoked brady-tachy with AV block and premature ventricular contractions (PVCs). Bradycardic responses to AITC were inhibited by the TRP channel blocker ruthenium red and the muscarinic antagonist atropine, but atropine did not prevent the tachycardic responses seen in the SH rats. Adrenergic inhibition with atenolol prevented the tachycardic responses, but did not prevent the bradycardic responses evoked by AITC in the SH rats. In healthy rats, AITC inhalation also caused a biphasic blood pressure response: a brief hypertensive phase followed by a hypotensive phase, while evoking hypertension in the SH rats. Atropine accentuated the hypertensive phase in all animals, while preventing the hypotension in the healthy animals. In all animals, AITC-evoked heart rate responses were not abolished by terazosin, the [U+F061]1 adrenoceptor inhibitor, which prevented the hypertensive responses. Anesthetics had profound effects on AITC-evoked bradycardia and AV block, which was abolished by urethane, ketamine and isoflurane. Nevertheless, AITC inhalation caused bradycardia and AV block in paralyzed and ventilated rats following pre-collicular decerebration. In conclusion, we provide evidence that activation of TRP channels expressed on nociceptive airway sensory nerves causes significant cardiovascular effects in healthy rats via reflex modulation of the autonomic nervous system (ANS), and that these effects are exacerbated in cardiovascular diseased rats.

Background-Previous studies have documented a high prevalence of atrial fibrillation (AF) in individuals with obstructive sleep apnea (OSA). Central sleep apnea (CSA) has been associated with AF in patients with heart failure. However, data from prospective cohorts are sparse and few studies have distinguished the associations of obstructive sleep apnea from CSA with AF in population studies. Methods and Results-We assessed the association of obstructive sleep apnea and CSA with incident AF among 2912 individuals without a history of AF in the SHHS (Sleep Heart Health Study), a prospective, community-based study of existing ("parent") cohort studies designed to evaluate the cardiovascular consequences of sleep disordered breathing. Incident AF was documented by 12-lead ECG or assessed by the parent cohort. obstructive sleep apnea was defined by the obstructive apnea-hypopnea index (OAHI). CSA was defined by a central apnea index >= 5 or the presence of Cheyne Stokes Respiration. Logistic regression was used to assess the association between sleep disordered breathing and incident AF. Over a mean of 5.3 years of follow-up, 338 cases of incident AF were observed. CSA was a predictor of incident AF in all adjusted models and was associated with 2-to 3-fold increased odds of developing AF (central apnea index >= 5 odds ratio [OR], 3.00, 1.40-6.44; Cheyne-Stokes respiration OR, 1.83, 0.95-3.54; CSA or Cheyne-Stokes respiration OR, 2.00, 1.16-3.44). In contrast, OAHI was not associated with incident AF (OAHI per 5 unit increase OR, 0.97, 0.91-1.03; OAHI 5 to <15 OR, 0.84, 0.59-1.17; OAHI 15 to <30 OR, 0.93, 0.60-1.45; OAHI >= 30 OR, 0.76, 0.42-1.36). Conclusions-In a prospective, community-based cohort, CSA was associated with incident AF, even after adjustment for cardiovascular risk factors.

Advanced computer technologies can transform the traditional electrocardiogram (ECG) monitoring system for better efficiency and accuracy. ECG records a heart's electrical activity using electrodes placed on the skin, and it has become an essential tool for arrhythmia detection. The complexity comes from the variety of patients' heartbeats and massive amounts of information for humans to process correctly. The first part of the thesis presents an image based two-dimensional convolution neural network (CNN) to classify the arrhythmia heartbeats with inter-patient paradigm. It includes a new data pre-processing method. The inter-patient paradigm simulates the practical use case of an ECG heartbeat classifier. Compared to the reported work in the literature, the proposed solution achieves superior experiment results. The rest of the thesis introduces the remote ECG monitoring system. The RESTful API design concepts of the system are described. The proposed API supports an efficient and secure way of interaction between each module in this remote monitoring system. / Graduate