2. A modified model of heart-arterial system was proposed for describing the timing of the second heart sound as a result of the heart-arterial interaction. Simulation results suggest that RS2 bears a significant negative correlation with both SBP and DBP as heart rate, cardiac contractility and peripheral resistance varies. The hypothesis was supported by the experimental data. To our knowledge, it is the first study describing the relation of the timing of S2 to BP by both the model-based study and experimental data. / 3. As a preliminary study, a linear predication model using RS2 with a novel calibration scheme was proposed for BP estimation and it has been evaluated in clinical test on 85 volunteers including 18 hypertensives. The results indicate that the approach has the potential to achieve the accuracy required for medical diagnosis. / Cuffless BP measurement has been proposed as a new concept in recent years to realize the continuous monitoring of BP. This research focuses on the investigation of cuffless BP monitoring technique using heart sound information. Specifically, the thesis proposes a new cuffless technique based on the timing of the second heart sound (S2), which will enable a novel wearable design of BP monitor, for instance, a multifunctional electronic stethoscope. / Finally, based on the findings on both theoretical and experimental studies, a linear prediction model with a novel calibration scheme has been proposed to estimate the BP using 1/RS2. The proposed method was evaluated in a clinical test on 85 volunteers aged 40+/-13 years, including 18 hypertensives. The average of BP measured by simultaneous ausculatory and oscillometric approaches was used as a reference. The results of clinical test shows that the RS2 based approach can estimate SBP and DBP within the 2.1+/-7.4 mmHg and 0.8+/-6.6 mmHg of the reference respectively, indicating the approach has the potential to achieve the accuracy required for medical diagnosis according to AAMI standard (mean error within +/-5mmHg and SD less than 8mmHg) and BHS protocol. / First, a mathematical model has been developed to investigate the effects of aortic BP on the aortic component (A2) in S2 produced by the vibration of the closed aortic valve. The nonlinear elasticity of aortic wall has been introduced to the model, reflecting the nature of aortic wall tissue and extending the model to the applications involving wide BP variations. The results of simulation show that the fundamental frequency and amplitude of A2 increases as aortic systolic blood pressure (SBP) is elevated, which is able to explain the 'accentuated S2' usually heard in the hypertensives. Nevertheless, the possibility of BP measurement using spectral information of externally recorded heart sounds still needs a careful examination because the frequency characteristics tends to be blurred during sound transmission. / Hypertension, known as 'a silent killer', is an important public health challenge, afflicting approximately 1 billion adults around the world. The monitoring of blood pressure (BP) is vitally important in order to identify hypertension and treat it earlier before serious health problems are developed. The conventional BP measurement provides only intermittent BP and causes circulatory interference if the cuff is inflated frequently. There is an urgent need to develop new devices which are fully wearable and unobtrusive for noninvasive and continuous monitoring of arterial BP in daily life. / Second, a modified model of heart-arterial system has been proposed in this thesis for describing the timing of aortic valve closure as a result of heart-arterial interaction. A timing parameter, RS2, was defined as the time delay from the peak of ECG R wave to the onset of S2. The study has investigated the relation between RS2 and aortic BP under varying peripheral resistance, arterial compliance, heart rate, cardiac contractility and preload. Based on the simulation results of parametric analysis, it is hypothesized that RS2 bears a significant negative correlation with both SBP and diastolic blood pressure (DBP) as the peripheral resistance, heart rate or cardiac contractility varies. / Third, in order to verify the findings of the model-based study, three experiments were carried out to explore the relationship between RS2 and BP. The alterations of RS2 in the dynamic-exercise experiments are mainly attributable to the interactive effect of the changes in heart rate, cardiac contractility and peripheral resistance, and the effect of heart rate is dominant. In two dynamic-exercise experiments, the timing parameter, RS2, exhibited a close inverse correlation with SBP (r =0.892 and r =0.845, p<0.05 in both experiments) and a moderate inverse correlation with diastolic blood pressure (DBP) (r = 0.687, p<0.05 and r =0.660, p>0.05). The correlations are comparable to those of PTT-based parameters. However, due to the restricted range of the BP variation, there was no significant correlation observed in long-term rest monitoring experiment. Moreover, the standard deviation (SD) of the errors for SBP and DBP estimated by linear fitting of 1/RS2 is close to that of PTT-based estimation. The results also suggest that the ability of RS2 on BP estimation is as good as that of the PTT based parameters. / To summarize, the original contributions of the thesis are: 1. By the introduction of the nonlinear elasticity of aortic wall, a mathematical model for the vibration of the closed aortic valve was improved and extended to the applications involving wide variations of BP To my knowledge, this represents the first study to look into the effects of aortic BP on the frequency characteristic of S2 from the theoretical point of view. / Zhang Xin-Yu. / "September 2006." / Adviser: Yuan-Ting Zhang. / Source: Dissertation Abstracts International, Volume: 68-09, Section: B, page: 6125. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Chan, Chun Hung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 77-84). / Abstracts in Chinese and English. / Acknowledgment: --- p.i / 摘要 --- p.ii / Abstract --- p.iv / List of Figure --- p.vi / List of Table --- p.viii / Content Page --- p.ix / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- The Difficulties --- p.1 / Chapter 1.2 --- The Solution --- p.2 / Chapter 1.3 --- Goal of the Present Work --- p.2 / Chapter Chapter 2 --- Background and Methodology --- p.3 / Chapter 2.1 --- Hypertension Situation and Problems Around the World --- p.3 / Chapter 2.1.1 --- Blood Pressure Variability (BPV) --- p.4 / Chapter 2.2 --- Blood Pressure Measuring Methods --- p.5 / Chapter 2.2.1 --- Traditional Blood Pressure Meters --- p.6 / Chapter 2.2.2 --- Limitation of Commercial Blood Pressure Meters --- p.7 / Chapter 2.2.3 --- Pulse-Transit-Time (PTT) Based Blood Pressure Measuring Watch --- p.7 / Chapter 2.3 --- Wearable Body Sensors Network / System --- p.8 / Chapter 2.4 --- Current Status of e-Textile Garment --- p.9 / Chapter 2.4.1 --- Blood Pressure Measurement in e-Textile Garment --- p.13 / Chapter 2.5 --- Wearable Intelligent Sensors and System for e-Health (WISSH) --- p.15 / Chapter 2.5.1 --- "Monitoring, Connection and Display" --- p.15 / Chapter 2.5.2 --- Treatment --- p.16 / Chapter 2.5.3 --- Alarming --- p.17 / Chapter Chapter 3 --- "A h-Shirt to Non-invasive, Continuous Monitoring of Arterial Blood Pressure" --- p.18 / Chapter 3.1 --- Design and Inner Structure of h-Shirt --- p.18 / Chapter 3.1.1 --- Choose of e-Textile Material --- p.21 / Chapter 3.1.2 --- Design of ECG Circuit --- p.23 / Chapter 3.1.3 --- Design of PPG Circuit --- p.26 / Chapter 3.2 --- Blood Pressure Estimation Using Pulse-Transit-Time Algorithm --- p.28 / Chapter 3.2.1 --- Principal --- p.28 / Chapter 3.2.2 --- Equations --- p.29 / Chapter 3.2.3 --- Calibration --- p.29 / Chapter 3.3 --- Performance Tests on h-Shirt --- p.30 / Chapter 3.3.1 --- Test I: BP Measurement Accuracy --- p.30 / Chapter 3.3.2 --- Test I: Procedure and Protocol --- p.30 / Chapter 3.3.3 --- Test I-Results --- p.31 / Chapter 3.3.4 --- Test II: Continuality BP Estimation Performance --- p.31 / Chapter 3.3.5 --- Test II - Experiment Procedure and Protocol --- p.32 / Chapter 3.3.6 --- Test II - Experiment Result --- p.33 / Chapter 3.3.7 --- Test II 一 Discussion --- p.43 / Chapter 3.4 --- Follow-up Tests on ECG Circuit --- p.47 / Chapter 3.4.1 --- Problems --- p.47 / Chapter 3.4.2 --- Assumptions --- p.48 / Chapter 3.4.3 --- Experiment Protocol and Setup --- p.48 / Chapter 3.4.4 --- Experiment Results --- p.53 / Chapter 3.4.5 --- Discussion --- p.56 / Chapter Chapter 4: --- Hybrid Body Sensor Network in h-Shirt --- p.59 / Chapter 4.1 --- A Hybrid Body Sensor Network --- p.59 / Chapter 4.2 --- Biological Channel Used in h-Shirt --- p.60 / Chapter 4.3 --- Tests of Bio-channel Performance --- p.62 / Chapter 4.3.1 --- Experiment Protocol --- p.62 / Chapter 4.3.2 --- Results --- p.62 / Chapter 4.4 --- Discussion and Conclusion --- p.63 / Chapter Chapter 5: --- Conclusion and Suggestions for Future Works --- p.66 / Chapter 5.1 --- Conclusion --- p.66 / Chapter 5.1.1 --- Structure of h-Shirt --- p.66 / Chapter 5.1.2 --- Blood Pressure Estimating Ability of h-Shirt --- p.67 / Chapter 5.1.3 --- Tests and Amendments on h-Shirt ECG Circuit --- p.67 / Chapter 5.1.4 --- Hybrid Body Sensor Network in h-Shirt --- p.67 / Chapter 5.2 --- Suggestions for Future Work --- p.68 / Chapter 5.2.1 --- Further Development of Bio-channel Biological Model --- p.68 / Chapter 5.2.2 --- Positioning and Motion Sensing with h-Shirt --- p.69 / Chapter 5.2.3 --- Implementation of Updated Advance Technology into h-Shirt --- p.69 / Appendix: Non-invasive BP Measuring Device - Finometer --- p.71 / Reference: --- p.77

A hipertensão arterial apresenta alta prevalência entre os receptores de transplante renal sendo considerada um fator de risco cardiovascular importante influenciando na sobrevida do paciente e do enxerto. O objetivo principal deste estudo foi comparar se o controle da pressão arterial nos pacientes transplantados renais por meio da utilização de monitorização residencial da pressão arterial é mais comparável ao resultado da monitorização ambulatorial da pressão arterial quando comparada à medida da pressão arterial de consultório. No período de março de 2008 a abril de 2009, foram avaliados prospectivamente 183 pacientes transplantados renais, com tempo de transplante de 1 a 10 anos. Os pacientes foram submetidos a três métodos de medida de pressão arterial (PA): medida de pressão arterial em consultório, monitorização residencial da pressão arterial (MRPA), e monitorização ambulatorial da pressão arterial (MAPA). Foram avaliados 183 pacientes, dentre eles 94 eram homens (54 %) e 89 mulheres (46 %). A idade média foi de 50 ± 11 anos. O tempo de transplante médio foi de 57 ± 32 meses. Noventa e nove pacientes receberam enxertos de doadores falecidos (54 %) e 84 foram receptores de doadores vivos (46 %). Quando avaliados usando a medida de PA obtida em consultório, 56,3% apresentavam-se PA elevada e 43,7% com PA normal com média de 138,9/82,3 ± 17,8/12,1mmHg. Entretanto, quando avaliados pela MRPA, 55,2% dos indivíduos apresentavam-se PA normal e 44,8 % apresentavam-se PA elevada com média de 131,1/78,5 ± 17,4/8,9. Utilizando a MAPA observamos que 63,9 % dos indivíduos apresentavam-se PA normal e 36,1 % dos indivíduos apresentavam-se PA elevada com média de 128,8/80,5 ± 12,5/8,1. Verifica-se que os dois métodos (Consultório e MRPA) tem concordância significativa com a MAPA, mas a MRPA tem uma concordância maior que a medida de Consultório, comprovado pelo teste Exato de Fisher, com valor descritivo de 0,026. Pelo teste de McNemar, verificamos que não há simetria nos dados nos dois métodos (MRPA e Consultório). Os índices de correlação linear de Pearson dos métodos, comparadas a MAPA, foram de 0,494 para medida de consultório e de 0,768 para MRPA, com a MRPA com melhor correlação com a MAPA. Comparando os erros dos dois métodos pelo teste t pareado, obteve-se o nível descritivo de 0,837, pelo qual concluí-se que o erro médio da PA de Consultório é igual ao do MRPA. Analisando a curva ROC para as medidas de PA em cada método, observa-se que a PA em consultório apresenta-se áreas sob a curva mais baixas que as obtidas pela MRPA em relação a MAPA. Concluí-se que os resultados pressóricos obtidos com a MRPA são mais comparáveis aos resultados obtidos pela MAPA em relação àqueles obtidos pela medida de consultório, sendo factível sua realização em um hospital publico / Hypertension is highly prevalent among kidney transplantation recipients and considered an important cardiovascular risk factor influencing patient survival and kidney graft survival. The aim of this study were to compare the blood pressure (BP) control in kidney transplant patients through the use of home blood pressure monitoring is more comparable with the results of ambulatory blood pressure monitoring compared to the measurement of office blood pressure. From March 2008 to April 2009 prospectively we were evaluated 183 kidney transplant recipients with time after transplantation 1 - 10 years. Patients underwent three methods for measuring blood pressure: office blood pressure measurement (OM), home blood pressure monitoring (HBPM) and ambulatory blood pressure monitoring (ABPM). We evaluated 183 patients, among them 94 men (54%) and 89 women (46%). The average age was 50 ± 11 years. The average time of transplant was 57 ± 32 months. Ninety-nine patients received grafts from deceased donors (54%) and 84 were recipients of living donors (46%). When assessed using OM, 56.3% presented with uncontrolled and 43.7% with adequate control of BP with an average of 138.9 / 82.3 ± 17.8 / 12.1 mmHg. However, when measured by HBPM, 55.2% of subjects were controlled and 44.8% presented with uncontrolled BP with an average of 131.1 / 78.5 ± 17.4 / 8.9 mmHg. Using the ABPM we observed that 63.9% of subjects had was controlled and 36.1% of patients presented uncontrolled BP with an average 128.8 / 80.5 ± 12.5 / 8.1.mmHg We found that the two methods (OM and HBPM) has a significant agreement, but the HBPM has a higher agreement than OM, confirmed by Fisher exact test, with descriptive value of 0.026.We found that there is no symmetry in the data for both methods with McNemar test. Person´s correlation for the ABPM with the other two methods were 0.494 for office measurement and 0.768 for HBPM, best value of HBPM with ABPM. Comparing the errors of the two methods by paired t-test, we obtained the descriptive level of 0.837, we conclude that the average error is equal to OM of HBPM. Looking at the ROC curve for BP measurements in each method, we observed that BP in practice presents lower than those obtained by HBPM in relation to ABPM. We conclude that the results obtained with HBPM were closer to the ABPM results than those obtained with blood pressure obtained at OM

A hipertensão arterial apresenta alta prevalência entre os receptores de transplante renal sendo considerada um fator de risco cardiovascular importante influenciando na sobrevida do paciente e do enxerto. O objetivo principal deste estudo foi comparar se o controle da pressão arterial nos pacientes transplantados renais por meio da utilização de monitorização residencial da pressão arterial é mais comparável ao resultado da monitorização ambulatorial da pressão arterial quando comparada à medida da pressão arterial de consultório. No período de março de 2008 a abril de 2009, foram avaliados prospectivamente 183 pacientes transplantados renais, com tempo de transplante de 1 a 10 anos. Os pacientes foram submetidos a três métodos de medida de pressão arterial (PA): medida de pressão arterial em consultório, monitorização residencial da pressão arterial (MRPA), e monitorização ambulatorial da pressão arterial (MAPA). Foram avaliados 183 pacientes, dentre eles 94 eram homens (54 %) e 89 mulheres (46 %). A idade média foi de 50 ± 11 anos. O tempo de transplante médio foi de 57 ± 32 meses. Noventa e nove pacientes receberam enxertos de doadores falecidos (54 %) e 84 foram receptores de doadores vivos (46 %). Quando avaliados usando a medida de PA obtida em consultório, 56,3% apresentavam-se PA elevada e 43,7% com PA normal com média de 138,9/82,3 ± 17,8/12,1mmHg. Entretanto, quando avaliados pela MRPA, 55,2% dos indivíduos apresentavam-se PA normal e 44,8 % apresentavam-se PA elevada com média de 131,1/78,5 ± 17,4/8,9. Utilizando a MAPA observamos que 63,9 % dos indivíduos apresentavam-se PA normal e 36,1 % dos indivíduos apresentavam-se PA elevada com média de 128,8/80,5 ± 12,5/8,1. Verifica-se que os dois métodos (Consultório e MRPA) tem concordância significativa com a MAPA, mas a MRPA tem uma concordância maior que a medida de Consultório, comprovado pelo teste Exato de Fisher, com valor descritivo de 0,026. Pelo teste de McNemar, verificamos que não há simetria nos dados nos dois métodos (MRPA e Consultório). Os índices de correlação linear de Pearson dos métodos, comparadas a MAPA, foram de 0,494 para medida de consultório e de 0,768 para MRPA, com a MRPA com melhor correlação com a MAPA. Comparando os erros dos dois métodos pelo teste t pareado, obteve-se o nível descritivo de 0,837, pelo qual concluí-se que o erro médio da PA de Consultório é igual ao do MRPA. Analisando a curva ROC para as medidas de PA em cada método, observa-se que a PA em consultório apresenta-se áreas sob a curva mais baixas que as obtidas pela MRPA em relação a MAPA. Concluí-se que os resultados pressóricos obtidos com a MRPA são mais comparáveis aos resultados obtidos pela MAPA em relação àqueles obtidos pela medida de consultório, sendo factível sua realização em um hospital publico / Hypertension is highly prevalent among kidney transplantation recipients and considered an important cardiovascular risk factor influencing patient survival and kidney graft survival. The aim of this study were to compare the blood pressure (BP) control in kidney transplant patients through the use of home blood pressure monitoring is more comparable with the results of ambulatory blood pressure monitoring compared to the measurement of office blood pressure. From March 2008 to April 2009 prospectively we were evaluated 183 kidney transplant recipients with time after transplantation 1 - 10 years. Patients underwent three methods for measuring blood pressure: office blood pressure measurement (OM), home blood pressure monitoring (HBPM) and ambulatory blood pressure monitoring (ABPM). We evaluated 183 patients, among them 94 men (54%) and 89 women (46%). The average age was 50 ± 11 years. The average time of transplant was 57 ± 32 months. Ninety-nine patients received grafts from deceased donors (54%) and 84 were recipients of living donors (46%). When assessed using OM, 56.3% presented with uncontrolled and 43.7% with adequate control of BP with an average of 138.9 / 82.3 ± 17.8 / 12.1 mmHg. However, when measured by HBPM, 55.2% of subjects were controlled and 44.8% presented with uncontrolled BP with an average of 131.1 / 78.5 ± 17.4 / 8.9 mmHg. Using the ABPM we observed that 63.9% of subjects had was controlled and 36.1% of patients presented uncontrolled BP with an average 128.8 / 80.5 ± 12.5 / 8.1.mmHg We found that the two methods (OM and HBPM) has a significant agreement, but the HBPM has a higher agreement than OM, confirmed by Fisher exact test, with descriptive value of 0.026.We found that there is no symmetry in the data for both methods with McNemar test. Person´s correlation for the ABPM with the other two methods were 0.494 for office measurement and 0.768 for HBPM, best value of HBPM with ABPM. Comparing the errors of the two methods by paired t-test, we obtained the descriptive level of 0.837, we conclude that the average error is equal to OM of HBPM. Looking at the ROC curve for BP measurements in each method, we observed that BP in practice presents lower than those obtained by HBPM in relation to ABPM. We conclude that the results obtained with HBPM were closer to the ABPM results than those obtained with blood pressure obtained at OM

No description available.

International Telemetering Conference Proceedings / October 22-25, 1984 / Riviera Hotel, Las Vegas, Nevada / Blood pressure signals recorded continuously in ambulatory patients using the Oxford system were analyzed by an IBM 370 computer in order to obtain beat by beat systolic and diastolic blood pressure along 24 hour blood pressure recordings. The method of digitizing the signal and the analysis of the sphygmogram are presented and discussed. Synthesis of the several thousands data obtained in 24 hour recordings and plotting of the data for clinical purposes and pharmacological studies are also reported.

Finally, the effects of external physical factors, such as temperature and contact force, on BP estimation based on m-NHA, were discussed and verified by experiments. Especially, a computational efficient algorithm was developed based on an optical model for motion resistant BP estimation, as well as the estimation of blood oxygen saturation (SaO2). We first developed an optical model with motion effect based on the photon-diffusion analysis, instead of the Beer-Lambert's law, which generally describes the light absorption but fails to account for light scattering in tissue. Based on the optical model, a novel motion resistant algorithm, minimum correlation discreet saturation transform (MCDST), was proposed for the estimation of arterial BP and SaO 2 as well. The novel algorithm is based on the time and time-delayed independence of the "true" signal and motion noise by use of dual PPGs (pulse oximeter). Experimental results indicate that MCDST has a comparable performance in SaO2 estimation and m-NHA calculation, as compared to another clinically verified motion-resistant algorithm---discreet saturation transform (DST). Most importantly, MCDST is much more computationally efficient than DST, because the former only uses simple linear algebra, while the latter uses the adaptive filter. It indicates that MCDST can reduce the required power consumption and circuit complexity of the implementation. It is vitally important for wearable devices, where the small physical size and long battery life are crucial. / First of all, a modified left-ventricle (LV) arterial coupling model was developed by incorporating a nonlinear pressure dependent compliance and two resistances for valve stenosis. A modified LV-arterial coupling model with pressure dependent compliance and taking into account the hypertensives with valve stenosis is quite necessary for proper description of the BP regulation for hypertensives with mitral and/or aortic stenosis, as well as normal people. / Hypertension is the most common cardiovascular disease and is a major public health problem in both developed and developing countries. As hypertension is often asymptomatic, continuous monitoring of blood pressure (BP) for the initiate treatment before the onset of organ damage is of vital importance for home healthcare. However, most of current BP meters, such as sphygmomanometer, are not suitable for the targeted applications because they provide only intermittent blood pressure readings and may cause circulatory interference with the usage of cuff. Moreover, they are not applicable in mobile environment due to the bulky design and the lack of efficient motion resistant algorithms. The objective of this research is to propose a motion resistant method for noninvasive and continuous BP measurement using dual photoplethysmograms (PPG), which could be potentially embedded in the portable or wearable devices for long term BP monitoring. / In summary, the research in this thesis not only covers the fundamental work, such as the modification of heart-arterial system coupling model and the proposal of a novel signal processing method MCDST, but also includes the practical techniques for the estimation of arterial BP as well as oxygen saturation. Expectations for further studies are suggested at the end of this thesis. / Secondly, based on the modified model, a novel parameter, normalized harmonic area (NHA), was proposed for BP estimation by quantifying the frequency distribution in the simulated aortic pressure waveforms. The excellent relationship between NHA and BP was verified by the simulation results. To establish a measurable parameter corresponding to NHA, PPG is investigated because it is widely used for the peripheral circulation monitoring and can be easily obtained at any location on the skin surface. Based on the assumption of quadratic transfer function from aortic pressure to PPG at fingertip, the discreet period transform (DPT) was applied on PPG signal to produce a modified NHA (m-NHA) for BP estimation. For the clinical tests on 85 subjects, the difference between the estimated and the measured blood pressure by m-NHA is 0.97+/-7.9mmHg for systolic blood pressure (SBP) and 0.40+/-4.5mmHg for diastolic blood pressure (DBP), respectively. This result is as good as that (0.73+/-7.6mmHg for SBP, and 0.40+/-4.5mmHg for DBP) from the widely reported pulse transit time (PTT) approach. / Yan Yongsheng. / "November 2005." / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6561. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

A taxa de controle da hipertensão arterial permanece subótima apesar dos amplos e intensos programas institucionais e o número das novas medicações. A combinação de drogas de diferentes mecanismos de ação vem se tornando uma alternativa para aumentar a redução na pressão arterial (PA) e aumentar seu controle, aumentar aderência ao tratamento e reduzir os eventos adversos. Um estudo fatorial 4X4 foi desenhado para determinar a eficácia e a segurança de telmisartana (T) mais anlodipino (A) em pacientes hipertensos estágios I e II. Pacientes hipertensos adultos (N=1461) estágios I e II (pressão arterial basal 153,212,1 &#8260;101,74,3 mm Hg) foram randomizados para 1 de 16 grupos de tratamento com T 0, 20, 40, 80 mg e A 0, 2.5, 5, 10 mg por oito semanas. A maior redução na média das pressões sistólica e diastólica foram observadas com T 80 mg mais A10 mg (- 26,4 &#8260;20,1 mm Hg; p<0,05 comparados com as monoterapias). A taxa de controle da PA foi também maior no grupo T 80mg mais A 10mg (76,5% [controle total] e 85,3% [controle da PA diastólica ]), e taxa de controle da PA >90% com esta combinação. O edema periférico maleolar foi o evento adverso mais frequente e ocorreu no grupo A 10mg (17,8%), porém, esta taxa foi marcadamente menor quando A foi usada associada com T: 11,4% (T20+A10), 6,2% (T40+ A10), e 11,3% (T80+A10). Um subestudo utilizando a monitorização ambulatorial da pressão arterial (MAPA) foi realizado na fase basal e após oito semanas de tratamento. A maior redução média das pressões nas 24 horas a partir do período basal foi registrada para a combinação de telmisartana 80 mg e anlodipino 10 mg e encontrou-se queda de 22,4/14,6 mmHg, de 11,9/6,9 mmHg para anlodipino 10 mg monoterapia e de 11,0/6,9 mmHg para telmisartana 80 mg (p< 0,001). Além disso, resultados relevantes foram também constatados numa análise post hoc de subgrupos incluindo idosos, obesos, diabéticos tipo 2 e hipertensão sistólica. A resposta anti-hipertensiva da combinação foi semelhante, independente de qualquer característica de cada subgrupo. Estes dados demonstram que telmisartana e anlodipino em combinação oferecem substancial redução e controle nas 24 horas superior às respectivas monoterapias em hipertensos estágios I e II. / The rate of control of hypertension remains suboptimal despite widespread educational programs and the increasing number of novel medications. The combination of drugs with different mechanism of action has become an alternative to improve blood pressure reduction and control, enhance adherence to the treatment and reduce adverse events. This randomized 4X4 factorial study determined the efficacy and safety of telmisartan (T) plus amlodipine (A) in hypertensive patients. Adults (N=1461) with stage 1 or 2 hypertension (baseline blood pressure (BP) 153.212.1 &#8260;101.74.3 mm Hg) were randomized to 1 of 16 treatment groups with T 0, 20, 40, 80 mg and A 0, 2.5, 5, 10 mg for 8 weeks. The greatest leastsquare mean systolic &#8260; diastolic BP reductions were observed with T80 mg plus A10 mg (- 26.4 &#8260;20.1 mm Hg; P<.05 compared with both monotherapies). BP control was also greater in the T80-mg plus A10-mg group (76.5% [overall control] and 85.3% [diastolic BP control]), and BP response rates >90% with this combination. Peripheral edema was most common in the A10-mg group (17.8%); however, this rate was notably lower when A was used in combination with T: 11.4% (T20 &#8260; A10), 6.2% (T40 &#8260; A10), and 11.3% (T80 &#8260; A10). Ambulatory BP monitoring (ABPM) was performed, at baseline and after 8 weeks of treatment; the endpoints of interest were the changes from baseline in 24-hour systolic and diastolic BP. Mean reductions from baseline in 24-hour BP for the combination of the highest doses of telmisartan 80 mg and amlodipine 10 mg were -22.4/-14.6 mmHg versus -11.9/-6.9 mmHg for amlodipine 10 mg and -11.0/-6.9 mmHg for telmisartan 80 mg (p< 0.001 for each comparison. This study also presents most of the relevant results in hypertensive patients and a post hoc analysis of subgroups including elderly, diabetics type 2, systolic hypertension and obese patients. These findings demonstrate that telmisartan and amlodipine in combination provide substantial 24 hour BP efficacy that is superior to either monotherapy in patients with stages 1 and 2 hypertension.

Thesis (Ph. D.)--University of Florida, 2003. / Title from title page of source document. Includes vita. Includes bibliographical references.

Objectives: To assess the role of ambulatory blood pressure monitoring in the diagnosis of hypertension in general practice. Background: Hypertension is usually diagnosed by casual office blood pressure readings. However, ambulatory blood pressure monitoring has shown that a significant proportion of patients diagnosed as hypertension in fact do not have hypertension. Method: Sixty four Indian patients diagnosed as having mild to moderate hypertension by casual measurements were subjected to a twenty four hour ambulatory blood pressure monitoring. A blood pressure load of >35% was classified as true hypertension and < 35% as white coat hypertension. White coat hypertensives were compared to the hypertensive group with respect to various demographic characteristics, and to correlate ambulatory blood pressure monitoring and casual blood pressure readings. Results: A prevalence of 23.44% white coat hypertension was found. In addition, the demographic profile of such patients show a preponderance of non-obese females (73.33%), the majority of whom are on concomitant medication (60%). A poor correlation was found between the casual office blood pressure readings and the twenty four hour ambulatory blood pressure readings in the white coat hypertensives as compared to the hypertensive group. Conclusion: White coat hypertension is common in patients diagnosed as having mild to moderate hypertension by casual blood pressure readings. There are no reliable clinical indicators to identify patients with white coat hypertension. Ambulatory blood pressure monitoring has been shown to be a useful method for differentiating white coat hypertensives from true hypertensives. / Thesis (M.Med)-University of Natal, 1997.