Doença renal crônica e fatores de risco para morte súbita cardíaca - denervaçao renal simpática: um sopro de esperança?

Vários estudos têm demonstrado forte associaçao independente entre doença renal crônica e eventos cardiovasculares, incluindo morte, insuficiência cardíaca e infarto do miocárdio. Ensaios clínicos recentes estendem essa gama de eventos adversos cardiovasculares, incluindo também arritmias ventriculares e morte súbita cardíaca. Além disso, outros estudos sugerem remodelaçao estrutural do coraçao e alteraçoes eletrofisiológicas nessa populaçao. Esses processos podem explicar o aumento do risco de arritmia na doença renal crônica e ajudam a identificar os pacientes que possuem maior risco de morte súbita cardíaca. A hiperatividade simpática é bem conhecida por aumentar o risco cardiovascular em pacientes com doença renal crônica e é uma marca registrada do estado hipertensivo essencial, que ocorre precocemente no curso clínico da doença. Nessa afecçao, a hiperatividade simpática parece ser expressa em sua fase clínica mais precoce, mostrando relaçao direta com a gravidade do estágio da insuficiência renal, sendo mais acentuada em sua fase terminal. A atividade nervosa simpática eferente e aferente na insuficiência renal é mediadora-chave para manutençao e progressao da doença. O objetivo desta revisao foi mostrar que o circuito fechado de realimentaçao do ciclo, em decorrência da hiperatividade adrenérgica, também agrava muitos dos fatores de risco responsáveis por causar morte súbita cardíaca, podendo ser um alvo potencial modificável pela denervaçao renal simpática percutânea. Pouco se sabe, ainda, sobre a viabilidade e a eficácia da denervaçao renal simpática percutânea na doença renal terminal

Health-related quality of life and blood pressure control in hypertensive patients with and without complications

INTRODUCTION: The goal of antihypertensive treatment is to reduce blood pressure without interfering in health-related quality of life (HRQL) OBJECTIVE: This study aimed to assess the influence of hypertension control upon HRQL in hypertensive patients with and without complications. MATERIALS AND METHODS: Seventy-seven hypertensive outpatients (71% women, 58% white, 60% with elementary school level education, average age 54 ± 8 years) were observed during a 12-month special care program (phase 1: clinical visits every two months, donation of all antihypertensive medications, meetings with a multidisciplinary team, and active telephone calls) and three years of standard care (phase 2: clinical visits every four months, medication provided by the drugstore of the hospital with a two-hour wait and a possible lack of medication, no meetings with a multidisciplinary team or active telephone calls). The patient HRQL was assessed using Bulpitt and Fletcher's Specific Questionnaire, as well as the SF-36 scores. Hypertensive patients were divided into "with complications" (n=37, diastolic blood pressure great than 110 mm Hg for patients with or without treatment, with clinically evident target-organ or other associated illness) and "without complications" (n=40). The variables studied were quality of life, blood pressure control, hypertension gravity, and demographic characteristics. RESULTS: In hypertensive patients with and without complications, both the systolic and diastolic blood pressure were significantly higher (p<0.05) in phase 2 of observation (143±18/ 84±11 and 144±21/93±11 mm Hg for patients with and without complications , respectively) relative to phase 1 (128±17/ 75±13 and 128±15/ 83±11mmHg). The proportion of patients with controlled blood pressure (defined as a blood pressure less than 140/90 mm Hg) decreased from 70% to 49% in the "with complications" group and from 78% to 50% in the "without complications" group during phase 2 of observation. The patients with complications showed a decrease in bodily pain, vitality, and mental health component summary scores in both phases. In phase 2, the patients without complications had significantly better HRQL scores compared to complicated patients using both the Bulpitt and Fletcher's Questionnaire and the SF-36 assessment of physical capacity, bodily pain, and vitality domain summary scores. With regards to hypertension control, there was a significant decrease from phase 1 to phase 2 in the vitality component summary scores and an increase in the emotional aspect component summary scores assessed by the SF-36, whereas Bulpitt and Fletcher's Questionnaire showed no differences in these scores. CONCLUSION: Special care programs with multidisciplinary activities, individualized and personalized assistance, easy access to pharmacological treatment, frequent meetings, and active telephone calls for hypertensive patients significantly increase blood pressure control but do not interfere with the HRQL

Hipertensão arterial em funcionários de um Hospital Universitário

PURPOSE: To find out the prevalence of hypertension in employees of the Hospital and relate it to social demographic variables. METHODS: Blood pressure measurement was performed with a mercury sphygmomanometer, using an appropriate cuff size for arm circumference, weight, and height in a population sample of 864 individuals out of the 9,905 employees of a University General Hospital stratified by gender, age, and job position. RESULTS: Hypertension prevalence was 26% (62% of these reported being aware of their hypertension and 38% were unaware but had systolic/diastolic blood pressures of >;140 and/or >;90 mm Hg at the moment of the measurement). Of those who were aware of having hypertension, 51% were found to be hypertensive at the moment of the measurement. The prevalence was found to be 17%, 23%, and 29% (P ;50 years, work unit being the Institute of Radiology and the Administration Building, educational level ;10 years, and body mass index >;30 kg/m². The multivariate logistic regression model revealed a statistically significant association of hypertension with the following variables: gender, age, skin color, family income, and body mass index. CONCLUSIONS: Hypertension prevalence was high, mainly in those who were not physicians or members of the nursing staff. High-risk groups (obese, non-white, men, low family income) should be better advised of prevention and early diagnosis of hypertension by means of special programs.OBJETIVO: Conhecer a prevalência de hipertensão arterial em funcionários de um complexo hospitalar e relacionar com variáveis sócio demográficas. MÉTODOS: Foi medida a pressão arterial com aparelho de coluna de mercúrio e manguito adequado à circunferência do braço, o peso e a altura em amostra de 864 dos 9.905 funcionários do Hospital Universitário estratificada de acordo com sexo, idade e ocupação. RESULTADOS: A prevalência de hipertensão foi de 26% (hipertensão referida = 62% ou pressão sistólica >; 140 e/ou >; 90 mm Hg no momento da medida = 38%). Dos que referiram 51% estavam hipertensos no momento da medida. A prevalência foi 17, 23 e 29% (p ; 50 anos, unidade de trabalho para o Instituto de Radiologia e Prédio da Administração, escolaridade ; 10 anos e índice de massa corporal (IMC) maior ou igual a 30 kg/m². O modelo de regressão logística com procedimento "stepwise" mostrou associação estatisticamente significante com hipertensão arterial para as variáveis: sexo, idade, cor da pele, renda familiar e IMC. CONCLUSÃO: A prevalência de hipertensão foi alta em funcionários do Complexo Hospital das Clínicas, principalmente nos de ocupação diferente de médico e enfermagem. Os grupos de maior risco (homens, cor preta, baixa renda familiar, obesos) precisam ser orientados quanto a prevenção e diagnóstico precoce da doença através de programas especiais

Chronic kidney disease and risk factors responsible for sudden cardiac death: a whiff of hope?

Several studies have shown a strong independent association between chronic kidney disease (CKD) and cardiovascular events, including death, heart failure, and myocardial infarction. Recent clinical trials extend this range of adverse cardiovascular events, also including ventricular arrhythmias and sudden cardiac death. Furthermore, other studies suggest structural remodeling of the heart and electrophysiological alterations in this population. These processes may explain the increased risk of arrhythmia in kidney disease and help to identify patients who are at increased risk of sudden cardiac death. Sympathetic hyperactivity is well known to increase cardiovascular risk in CKD patients and is a hallmark of essential hypertensive state that occurs early in the clinical course of the disease. In CKD, the sympathetic hyperactivity seems to be expressed at the earliest clinical stage of the disease, showing a direct relationship with the severity of the condition of renal failure, being more pronounced in the terminal stage of CKD. The sympathetic efferent and afferent neural activity in kidney failure is a key mediator for the maintenance and progression of the disease. The aim of this review was to show that the feedback loop of this cycle, due to adrenergic hyperactivity, also aggravates many of the risk factors responsible for causing sudden cardiac death and may be a potential target modifiable by percutaneous renal sympathetic denervation. If it is feasible and effective in end-stage renal disease, little is known

Home and Ambulatory Blood Pressure to Identify White Coat and Masked Hypertension in the Pediatric Patient

OBJECTIVE To evaluate the effect of the environment and the observer on the measurement of blood pressure (BP) as well as to compare home BP (HBP) and ambulatory BP (ABP) measurements in the diagnosis of white coat hypertension (WCH) and masked hypertension (MH) in children and adolescents with hypertension (HT). METHODS BP of 40 patients with HT (75% of which had secondary HT and were on antihypertensive medication), mean age 12.1 years was evaluated through casual measurements at the clinic and at the HT unit, HBP for 14 days with the OMRON HEM 705 CP monitor (Omron, Tokyo, Japan) and ABP performed with SPACELABS 90207 (Spacelabs, Redmond, WA), for 24 h. RESULTS HT was diagnosed at the doctor`s office by ABP and HBP in 30/40, 27/40, and 31/40 patients, respectively. Based on office BP and ABP, 60% of patients were normotensive, 17.5% HT, 7.5% had WCH, and 15% had MH, whereas based on office BP and HBP 65, 12.5, 10, and 12.5% of patients were classified according to these diagnoses, respectively. There was considerable diagnostic agreement of HT by ABP and HBP (McNemar test, P < 0.01) (kappa = 0.56). CONCLUSION In hypertensive children and adolescents, HBP and ABP present comparable results. HBP appears to be a useful diagnostic test for the detection of MH and WCH in pediatric patients

Oral Fludrocortisone Test for Salt-Sensitive Screening in Hypertensive Patients: A Randomized Crossover Trial

Background. Salt sensitivity is associated with an increased cardiovascular risk, but the gold standard method (diet cycles) requires 24-h urine samples and has poor patient compliance. Objectives. Test the hypothesis that oral fludrocortisone (0.4 mg per day for 7 days) is a good alternative in identifying salt-sensitive patients. Methodology. We conducted a randomized crossover study with 30 hypertensive individuals comprising the following steps: (1) washout; (2) phase A (low- and high-sodium diet cycles); (3) washout 2; (4) phase B (fludrocortisone test). Phase A and B steps were performed in a random way. Consistent with the literature, we found that 53.3% were salt-sensitive according to the reference test. Using the ROC curve, the fludrocortisone test defined salt sensitivity by a median blood pressure increase of ≥3 mmHg. A good accuracy of fludrocortisone in detecting salt sensitivity was observed (AUC: 0.732±0.065; p<0.001), with 80% sensitivity and 53% specificity. Conclusion. The fludrocortisone test is a good option for screening salt sensitivity in hypertensive patients. However, the low specificity prevents this test from being an ideal substitute to the labor-intensive diet cycles exam in the definition of salt sensitivity. This clinical trial is registered with NCT01453959

Sympathetic nerve activity is decreased during device-guided slow breathing

It is known that slow breathing (<10 breaths min(-1)) reduces blood pressure ( BP), but the mechanisms involved in this phenomenon are not completely clear. The aim of this study was to evaluate the acute responses of the muscle sympathetic nerve activity, BP and heart rate (HR), using device-guided slow breathing ( breathe with interactive music (BIM)) or calm music. In all, 27 treated mild hypertensives were enrolled. Muscle sympathetic nerve activity, BP and HR were measured for 5min before the use of the device (n=14) or while subjects listened to calm music (n=13), it was measured again for 15 min while in use and finally, 5min after the interventions. BIM device reduced respiratory rate from 16 +/- 3 beats per minute (b.p.m) to 5.5 +/- 1.8 b.p.m (P<0.05), calm music did not affect this variable. Both interventions reduced systolic (-6 and -4mmHg for both) and diastolic BPs (-4mmHg and -3mmHg, respectively) and did not affect the HR (-1 and -2 b.p.m respectively). Only the BIM device reduced the sympathetic nerve activity of the sample (-8bursts min(-1)). In conclusion, both device-guided slow breathing and listening to calm music have decreased BP but only the device-guided slow breathing was able to reduce the peripheral sympathetic nerve activity. Hypertension Research ( 2010) 33, 708-712; doi: 10.1038/hr.2010.74; published online 3 June 201

Post-concurrent exercise hemodynamics and cardiac autonomic modulation

Concurrent training is recommended for health improvement, but its acute effects on cardiovascular function are not well established. This study analyzed hemodynamics and autonomic modulation after a single session of aerobic (A), resistance (R), and concurrent (A + R) exercises. Twenty healthy subjects randomly underwent four sessions: control (C:30 min of rest), aerobic (A:30 min, cycle ergometer, 75% of VO(2) peak), resistance (R:6 exercises, 3 sets, 20 repetitions, 50% of 1 RM), and concurrent (AR: A + R). Before and after the interventions, blood pressure (BP), heart rate (HR), cardiac output (CO), and HR variability were measured. Systolic BP decreased after all the exercises, and the greatest decreases were observed after the A and AR sessions (-13 +/- 1 and -11 +/- 1 mmHg, respectively, P < 0.05). Diastolic BP decreased similarly after all the exercises, and this decrease lasted longer after the A session. CO also decreased similarly after the exercises, while systemic vascular resistance increased after the R and AR sessions in the recovery period (+4.0 +/- 1.7 and +6.3 +/- 1.9 U, respectively, P < 0.05). Stroke volume decreased, while HR increased after the exercises, and the greatest responses were observed after the AR session (SV, A = -14.6 +/- 3.6, R = -22.4 +/- 3.5 and AR = -23.4 +/- 2.4 ml; HR, A = +13 +/- 2, R = +15 +/- 2 vs. AR = +20 +/- 2 bpm, P < 0.05). Cardiac sympathovagal balance increased after the exercises, and the greatest increase was observed after the AR session (A = +0.7 +/- 0.8, R = +1.0 +/- 0.8 vs. AR = +1.2 +/- 0.8, P < 0.05). In conclusion, the association of aerobic and resistance exercises in the same training session did not potentiate postexercise hypotension, and increased cardiac sympathetic activation during the recovery period.CAPES (Demanda Social)CNP