Greater Decrease In Blood Pressure Research Articles

Effects of DASH diet with or without time-restricted eating in the management of stage 1 primary hypertension: a randomized controlled trial

BackgroundTime-restricted eating (TRE), a popular form of intermittent fasting, has shown benefits for improving metabolic diseases and cardiometabolic health. However, the effect of TRE in the regulation of blood pressure in primary hypertension remains unclear.MethodsA 6-week randomized controlled trial was conducted, in which a total of 74 stage 1 primary hypertensive patients without high-risk were randomly assigned to Dietary Approaches to Stop Hypertension (DASH) group (n = 37) or DASH + TRE group (n = 37). Participants in the DASH + TRE group were instructed to consume their food within an 8-h window. Scientific research platform in We Chat application was used to track participants. The primary outcome was blood pressure. The secondary outcomes included body composition, cardiometabolic risk factors, inflammation-related parameters, urinary Na+ excretion, other clinical variables and safety outcomes.ResultsThe reduction of systolic blood pressure and diastolic blood pressure were 5.595 ± 4.072 and 5.351 ± 5.643 mm Hg in the DASH group and 8.459 ± 4.260 and 9.459 ± 4.375 mm Hg in the DASH + TRE group. DASH + TRE group improved blood pressure diurnal rhythm. Subjects in DASH + TRE group had decreased extracellular water and increased urinary Na+ excretion. Furthermore, the decrease in blood pressure was associated with a reduction of extracellular water or increase in urinary Na+ excretion. In addition, safety outcomes such as nighttime hunger were also reported.ConclusionOur study demonstrated that 8-h TRE + DASH diet caused a greater decrease in blood pressure in stage 1 primary hypertensive patients than DASH diet. This study may provide novel insights into the benefits of lifestyle modification in the treatment of primary hypertension.Trial registrationhttps://www.chictr.org.cn/ (ChiCTR2300069393, registered on March 15, 2023).

The halothane era in pediatric anesthesia: The convergence of a cardiac depressant anesthetic with the immature myocardium of infancy.

Introduced in the late 1950s, halothane became the anesthetic of choice for inhalational induction of children for over 40 years. Halothane enjoyed a generally favorable safety record during its time, but its cardiac contractility depressant effect-well tolerated by most age groups-was profoundly heightened in neonates and infants, leading to increased incidences of hypotension and cardiac arrest. The neonatal myocardium is immature and is characterized by poor ventricular compliance, poor contractility due to fewer contractile elements, immature sympathetic innervation with decreased norepinephrine stores, and immature mechanisms for storage and exchange of calcium in the sarcoplasmic reticulum. Invitro studies of myocardial contractility of mammalian fetal and adult myocardium demonstrated that the fetal heart was twice as sensitive to halothane as the adult. Clinical studies demonstrated that most neonates and infants less than 6 months of age experienced hypotension during halothane induction of anesthesia and significantly (p < .01) greater decreases in blood pressure than older children at equipotent concentrations of halothane. Intraoperative cardiac arrest during the halothane era occurred over twice as frequently in neonates aged less than 1 month than in infants aged 1-12 months and nearly 10 times more frequently than children 1-5 years of age. Halothane was associated with 66% of intraoperative drug-related cardiac arrests in children. The halothane era began to close in the late 1990s with the introduction of sevoflurane, which had a more favorable hemodynamic profile. Shortly thereafter, halothane was completely displaced from pediatric anesthesia practice in North America.

Implication of changes in xanthine oxidase activity following hemodialysis

BackgroundXanthine oxidase activity has a key role in the development of oxidative stress and progression of cardiovascular diseases. However, the change of xanthine oxidase activity following hemodialysis and its prognostic impact remain uncertain.MethodsWe prospectively included hemodialysis patients who did not take any anti-hyperuricemic agents and measured their xanthine oxidase activity before and after the index hemodialysis. The impact of change in xanthine oxidase activity during hemodialysis on cardiovascular death were investigated.ResultsA total of 46 patients (median 72 years old, 29 men) were included. During hemodialysis, a common logarithm of xanthine oxidase activity decreased significantly from 1.16 (0.94, 1.27) to 1.03 (0.80, 1.20) (p < 0.01). Of them, xanthine oxidase activity remained unchanged or increased in 16 patients, who had a greater decrease in blood pressure and more hemoconcentration compared with others. Two–year survival from cardiovascular death was not significantly stratified by the changes in xanthine oxidase activity (p = 0.43).ConclusionsDuring hemodialysis, xanthine oxidase activity decreased among the overall cohort, whereas some patients experienced its increases, which might be associated with hypotension and hemoconcentration during hemodialysis. Further larger-scale studies are required to validate our findings and find clinical implication of change in xanthine oxidase activity during hemodialysis.

ГЕМОДИНАМИКА БОЛЬШОГО КРУГА КРОВООБРАЩЕНИЯ У МУЖЧИН МОЛОЖЕ 60 ЛЕТ С ИНФАРКТОМ МИОКАРДА И ОСТРЫМ ПОВРЕЖДЕНИЕМ ПОЧЕК

Relevance. Hemodynamics changes in myocardial infarction complicated by acute kidney injury are interpreted in different ways. Aim. To evaluate peripheral hemodynamics changes in men under 60 years old with myocardial infarction complicated by acute kidney injury to improve prevention and outcomes. Material and methods. The study included men 19-60 years old with type I myocardial infarction. The patients were divided into two age-comparable groups: I - study group, with acute kidney injury - 25 patients; II - control, without it - 486 patients. A comparative assessment of circulation indices changes in first 48 hours (1) and the end of third week disease (2), their dynamics, also acute kidney injury development risk analysis (ANOVA) were performed. Results. The study group differed from the control group in lower values of heart rate1 (66.3±12.2 and 75.8±18.8 (bpm), respectively; p=0.003) and higher - arterial pressure, systolic1 (155.6±24.0 and 139.5±28.9 (mm Hg); p=0.006), diastolic1 (98.0 ± 16.0 and 86.6 ± 18.9 (mm Hg); p = 0.002), mean1 (117.2±17.6 and 104.3±21.3 (mm Hg); p=0.001). In the study group compared in the control group, there was a greater decrease in blood pressure (mean: -18.3 and -8.3%, respectively) and total peripheral resistance (-33.5 and -26.3%) (p&lt;0.0001). The risk markers of the acute kidney injury development were the mean arterial pressure1≥106.7, systolic1≥140.0, diastolic1≥90.0 (mm Hg) and heart rate1˂66 bpm. Conclusions. Men under 60 years old with acute kidney injury in myocardial infarction are characterized by arterial hypertension and bradycardia in the first hours of the disease, as well as more pronounced decline dynamics of blood pressure and total peripheral resistance at the end of its subacute period. The listed above values of the circulation parameters should be used in the high-risk groups for the acute kidney injury development formation, as well as prognostic modeling.

ОСОБЕННОСТИ ФУНКЦИОНАЛЬНОГО СОСТОЯНИЯ СЕРДЕЧНО-СОСУДИСТОЙ СИСТЕМЫ И ЕЕ АДАПТАЦИИ К ФИЗИЧЕСКИМ НАГРУЗКАМ У ДЕТЕЙ С НАРУШЕНИЕМ ЗРЕНИЯ

Aim. The aim of the paper was to study the features of hemodynamics in visually impaired children at rest, after limited physical activity, and in different modes of physical activity. Materials and methods. The study involved visually impaired girls aged 7-8 and engaged in physical activity according to the program of a special school (n = 32) and visually impaired girls involved in adaptive swimming (n = 14). Children of the same age without visual impairment (n = 30) were examined as a control group. The functional state of the cardiovascular system was assessed according to the indicators of the pumping function of the heart, total peripheral vascular resistance and blood pressure using the REACARD automated device and the Omron M2 Basic tonometer. The Martinet – Kushelevsky test (20 squats per 30 seconds) was used as limited phy­sical activity. Results. It was found that compared with the control group, girls with visual impairment at rest demonstrated lower blood pressure and stroke volume accompanied by an increase in heart rate. Limited physical activity in visually impaired girls resulted in a greater decrease in blood pressure in the absence of changes in stroke volume and a sharp increase in heart rate. At the same time, children involved in swimming were characterized by a more favorable response to physical activity accompanied by an increase in stroke volume against a moderate increase in heart rate and blood pressure and a decrease in total peripheral vascular resistance. Conclusion. Visually impaired girls are characterized by a lower level of hemodynamic performance at rest and the lack of formation of urgent adaptation to dynamic physical activity compared with the control group. Special classes that include adaptive swimming have a positive effect on the cardiovascular system and increase its adaptive capabilities.

Response to: Resonance Frequency Assessment: The Impact and Implications of Inaccurate Assessment in the Clinical Use of Heart Rate Variability Biofeedback

Response to: Resonance Frequency Assessment: The Impact and Implications of Inaccurate Assessment in the Clinical Use of Heart Rate Variability Biofeedback

Blood pressure in early and mid-pregnancy and the risk of small-for-gestational-age birth: findings of a large cohort study in China.

The influences of blood pressure in early to mid-pregnancy on the risk of small-for-gestational-age (SGA) birth are not clear. Our objective was to examine the associations of the blood pressure levels at 10 and 18 gestational weeks with the risk of SGA birth. Data were obtained from the Chinese Maternal and Newborn's Health Monitoring System (MNHMS). In total, 50745 Chinese women who delivered a single live infant at a gestational age of between 28 and 42 weeks were included in this analysis. Blood pressure, birth outcome and other related information were obtained during antenatal visits by obstetricians. Logistic regression models were used to examine the associations, adjusting for potential confounders. The total incidence of SGA birth was 8.9%. High blood pressure levels at 10 gestational weeks significantly increased the risk of SGA birth (SBP: RR = 1.32, 95% CI: 1.11-1.56; DBP: RR = 1.10, 95% CI: 1.05-1.14). The incidence of SGA birth was not associated with the DBP at 18 gestational weeks but showed a U-shaped relationship with SBP. A decrease in blood pressure from 10 to 18 gestational weeks was associated with an increased risk of SGA birth (SBP: RR = 1.03, 95% CI: 1.00-1.07; DBP: RR = 1.05, 95% CI: 1.02-1.09). Our results provide evidence on the relationship of blood pressure in early and mid-pregnancy with SGA birth. Higher blood pressures during early pregnancy and greater decreases in blood pressure from early to mid-pregnancy increased the risk of SGA birth, indicating a continuum of risk for SGA birth based on blood pressure starting during early pregnancy.

Effect of Switching to Azilsartan From Fixed-Dose Combination of an Angiotensin II Receptor Blocker and Calcium Channel Blocker or a Thiazide in Patients With Hypertension.

BackgroundDespite the availability of antihypertensive treatments, fewer than half of patients who receive treatment successfully achieve blood pressure (BP) goals. The purpose of this study was to evaluate the effect of switching to azilsartan 40 mg from a fixed-dose combination tablet of an angiotensin II receptor blocker (ARB) and amlodipine at 5 mg or azelnidipine at 16 mg (ARB/CCB) or an ARB and hydrochlorothiazide (HCT) at 6.25 mg or 12.5 mg (ARB/HCT) on BP.MethodsThis prospective, multicenter, open-labeled, single-arm study included 40 patients treated with a fixed-dose combination tablet of an ARB/CCB or an ARB/HCT, which was switched to azilsartan 40 mg after enrollment. The primary outcome was the change in BP from baseline to the 24-week follow-up.ResultsOf the 40 patients who completed this study, 33 did not require changes in their antihypertensive medications after switching to azilsartan, and their BP did not change from baseline to follow-up. However, the systolic BP in seven patients was elevated at 12 weeks, and amlodipine at 5 mg was therefore added; these patients’ baseline medications were an ARB/CCB (n = 6) and an ARB/HCT (n = 1). In all patients, the serum potassium level was slightly increased after switching to azilsartan at 6 months, while the serum creatinine, hemoblobinA1c, and lipid profile did not change.ConclusionsAzilsartan at 40 mg did not result in a greater decrease in BP than a fixed-dose combination tablet of an ARB/CCB or an ARB/HCT. However, our findings suggest a substantial BP-lowering effect of azilsartan at 40 mg in patients with hypertension.

REDUCING CARDIOVASCULAR RISK IN PATIENTS WITH MORBID OBESITY AFTER BARIATRIC SURGERY

Objective: The rate of obesity is rising logarithmically, especially morbid obesity (BMI > 40 kg/m2). Obesity is commonly associated with multiple conditions imparting adverse cardiovascular risk including, hypertension, dyslipidemia and diabetes. Severe obesity is generally refractory to lifestyle modification, including diet, exercise and pharmacological treatment. The main objective of the study is to confirm the use of bariatric surgery as a means to reduce cardiovascular risk in severely obese patients. Design and method: We examined 164 patients with morbid obesity (BMI > 40 kg/m2), they formed two groups. The first group included 81 patients who treated with diet, physical activity and drugs. The second group included 83 patients who using bariatric surgery (gastric bypass). Patients were examined before and after 6 months of treatment. All patients underwent clinical examination, determination of anthropometric parameters, measurement office SBP and DBP, daily monitoring of blood pressure, echocardiography, exploration indicators carbohydrate and lipid metabolism, definition cardiovascular risk with using scales SCORE, PROCAM, DRS, FRAMINGHAM. Results: It was found that after 6 months of treatment weight loss was observed in both groups. A more significant decrease in body weight was observed in patients after surgical treatment (in first group by 4.6%, in the second group by 22.8%). Weight loss in patients after surgical treatment was associated with a greater decrease in blood pressure, improvement in the daily BP profile, changes in the structural and functional characteristics of the myocardium, decrease in the number of patients with LV hypertrophy, decrease LDL cholesterol, TG, glucose level, which was accompanied by a decrease in the number of patients with glucose intolerance (by 41.2%) and with diabetes (by 75%). Weight loss was associated with reducing the number of patients at very high risk on a scale SCORE by 78%, on a scale PROCAM by 100%, on a scale FRAMINGHAM by 95,6% and on a scale DRS by 13% in patients after surgical treatment. Conclusions: Weight loss with the use of bariatric surgery contributes to the normalization of BP, reduces LV hypertrophy, has a positive effect on the lipid, carbohydrates profile and reduces cardiovascular risk.

Effects of isometric handgrip training in patients with cardiovascular disease: rationale and design of the ISOPRESS network

Abstract Meta-analytical studies have indicated that isometric handgrip training promotes significant reduction in blood pressure in hypertensive patients with similar or greater decreases in blood pressure than observed after aerobic and dynamic resistance training. However, several gaps in the literature still need to be addressed. Thus, we designed the ISOPRESS network group, which consists of a task force of different research groups aimed at analyzing the effects of isometric handgrip training on different contexts, parameters, and populations. Thus, the aim of this study was to describe the rationale and design behind the ISOPRESS, presenting the methods employed. The ISOPRESS questions involve whether isometric handgrip training is effective in hypertensives in different settings (ISOPRESS 1 - unsupervised training and ISOPRESS 2 - public health system), whether it works in patients with other cardiovascular diseases (ISOPRESS 3 - obstructive sleep apnea and ISOPRESS 4 - peripheral artery disease) and what are the mechanisms underlying the effects of isometric handgrip training in hypertensives (ISOPRESS 5 - neural mechanism). The study will yield information on the effectiveness of isometric handgrip training in different settings and patients with other cardiovascular diseases. Finally, it will help to understand the mechanisms involved in reducing blood pressure in hypertensives.

PERSONALIZED EXERCISE TRAINING PROGRAM AS A COUNTERMEASURE TO ORTHOSTATIC INTOLERANCE AFTER SPACE FLIGHTS.

PERSONALIZED EXERCISE TRAINING PROGRAM AS A COUNTERMEASURE TO ORTHOSTATIC INTOLERANCE AFTER SPACE FLIGHTS.

The Effect Of Inorganic Nitrate And Exercise On Blood Pressure In Pre-and Hypertension Subjects.

Dietary supplementation of inorganic nitrate (NO-3) reduces blood pressure (BP) in normal and hypertensive subjects. An acute bout of exercise also reduces BP in many normotensive and in most hypertensive individuals. The possible additive hypotensive effect of NO-3 plus exercise has not been investigated in pre- and hypertensives. PURPOSE: To assess whether intake of NO-3 followed by maximal exercise may potentiate the hypotensive effect of both procedures. METHODS: Ten pre- or hypertensive subjects participated in a randomized double-blind study one week apart. (7 men, 3 women) (BP ≥ 120/80mmHg) (Systolic Blood Pressure SBP/Diastolic Blood Pressure DBP). Subjects arrived in the fasting condition and without medications and ingested either a fruit and vegetables juice containing 25O g of NO-3 (8 mmol/L of NO-3) (N) or nitrate depleted juice (P). After 90 minutes post supplementation, they performed a MAXCAP-T treadmill test. BP was obtained 10 minutes post arrival (BP1), 90 minutes post dietary supplementation (BP2), immediately Post MAXCAP-T (BP3), 10 minutes after MAXCAP-T(BP4), and 150 minutes post MAXCAP-T (BP5). Statistics anova, paired t test, t test two groups. RESULTS: After ingestion of N, SBP and DBP were reduced by 11 and 6 mmHg, respectively. Meanwhile, after P, SBP decreased 3 mmHg while DBP did not change. Following MAXCAP-T, SBP increased less after N than P (26 vs 31 mmHg, P <0.05). DBP decreased 2 and increased 5 mmHg with N and P, respectively (P <0.05). Ten minutes after MAXCAP-T, SBP was 20 and 11 mmHg lower than BP1 for N and P respectively (P< 0.05). The difference between N and P was significant (P <0.05). DBP was reduced 10 mmHg with N with no changes in P. After 150 minutes of MAXCAP-T, SBP was 24 and 16 mmHg lower than BP1 for N and P, respectively (p < 0.05). Meanwhile, DBP was 8 mmHg lower than BP1 for N without significant changes for P. CONCLUSIONS: Ingestion of inorganic nitrate decreased SBP and DBP before exercise and prevented increases in SBP and DBP immediately after acute maximal exercise. The combination of NO-3 and exercise resulted in greater decreases in BP in pre- and hypertensive patients as compared with P.

Diferentes ordens do exercício combinado: efeitos agudos de 24 horas sobre a pressão arterial de atletas

Resumo Verificar as respostas de 24 horas da pressão arterial (PA) em jovens adultos após diferentes ordens de execução do exercício aeróbio (EA) e resistido (ER). Participarão do estudo dez homens saudáveis (22,6 ± 70,3; 3.7 anos ± 5,8 kg; 175,9 ± 5,8 centímetros). O estudo consistiu em quatro sessões experimentais realizadas de forma aleatórias: EA + ER (AR); ER + EA (RA); Circuito Concorrente (CC) e controle (CO). Todas as sessões tiveram a mesma duração e intensidade, EA: 15 min a 90% do limar de lactato mínimo indireto; ER: 15min a 90% de 12 RM com 12 repetições (seis exercícios). A PA foi medida antes, durante e 1 h (Microlife® BP3A1C) após a realização de exercícios em laboratório e 23 h durante as atividades diárias, utilizando a medição da pressão arterial ambulatorial (Dyna-MAPA®). A pressão arterial sistólica (PAS) no período de 24 horas e de vigília, e a diastólica (PAD), no período de 24 horas, o sono e de vigília, e a média da PA no período de vigília foram menores na sessão RA em comparação com a sessão CO apresentando um tamanho do efeito de moderado a alto (d de Cohen = -0,46 / -0,78). A área sob a curva da PAD na sessão AR foi menor do que na sessão CO no período de vigília (1004 ± 82 vs. 1065 ± 107; p &lt; 0,047) e 24 h (1456 ± 103 vs 1528 ± 132; p &lt; 0,026) períodos. A sessão RA apresentou maiores pontos de redução da PA durante 24 horas em relação ao outros protocolos.

Abstract PR040

Background & Objectives: Patients with diabetes are at increased risk of complications and death in the peri-operative period compared to non-diabetics. Cardiac autonomic neuropathy (CAN) is a frequent complication of type 1 and 2 diabetes, attenuating the compensatory response of the cardiovascular system to anaesthesia[1]. The resulting hypotension may lead to ischemia of vital organs. We hypothesize that the presence of CAN is associated with peri-operative hypotension. The purpose of this study is to investigate the utility of pre-operative screening for CAN to predict peri-operative hypotension and the vasopressor need amongst diabetic patients. Materials & Methods: Diabetic patients undergoing elective surgery in general- or spinal anaesthesia are recruited into a double-blinded cross-sectional study. The presence of CAN is investigated days to weeks prior to surgery by internationally accepted standard tests: i) heart rate variability during 5 minutes´ rest (HRV-5), ii) paced breathing, iii) posture change, and iv) Valsalva’s maneuvre[2]. Current medication, type, duration and possible late complications of diabetes are recorded. The patient’s blood pressure is measured non-invasively on both arms. Peri-operative data are extracted from the anaesthesia record. Results: We present data (mean ±sd) from 26 diabetic patients, of whom 22 had type 2 diabetes. The average age and BMI were 62±9 years and 31±6 kg/m2, respectively. All patients underwent general anaesthesia. The preliminary analysis show an association between HRV-5 and hypotension during the induction of anaesthesia (i.e. from the administration of a sedative bolus medication and the subsequent 10 minutes). Linear regression analysis showed that a lower HRV-5 was associated with a greater decrease in blood pressure (P=0.01). When stratified by low, medium, and high HRV-5, the lowest measured mean arterial blood pressure (MAP) was 58±18, 60±9, 71±14 mmHg, respectively. Furthermore, patients with a dip in MAP below 60 mmHg tended to have a lower HRV-5 compared to the other patients (P=0.06). The remaining CAN tests were not associated with MAP. Conclusion: The preliminary results show that peri-operative hypotension is associated with HRV-5. Once the study is completed, we are able to assess the utility of CAN screening to predict peri-operative hypotension. If successful, a pre-operative screening for CAN may aid the planning of cardiovascular monitoring during anaesthesia.

Adherence to Antihypertensive Treatment and the Blood Pressure-Lowering Effects of Renal Denervation in the Renal Denervation for Hypertension (DENERHTN) Trial.

The DENERHTN trial (Renal Denervation for Hypertension) confirmed the blood pressure-lowering efficacy of renal denervation added to a standardized stepped-care antihypertensive treatment for resistant hypertension at 6 months. We report the influence of adherence to antihypertensive treatment on blood pressure control. One hundred six patients with hypertension resistant to 4 weeks of treatment with indapamide 1.5 mg/d, ramipril 10 mg/d (or irbesartan 300 mg/d), and amlodipine 10 mg/d were randomly assigned to renal denervation plus standardized stepped-care antihypertensive treatment, or the same antihypertensive treatment alone. For standardized stepped-care antihypertensive treatment, spironolactone 25 mg/d, bisoprolol 10 mg/d, prazosin 5 mg/d, and rilmenidine 1 mg/d were sequentially added at monthly visits if home blood pressure was ≥135/85 mm Hg after randomization. We assessed adherence to antihypertensive treatment at 6 months by drug screening in urine/plasma samples from 85 patients. The numbers of fully adherent (20/40 versus 21/45), partially nonadherent (13/40 versus 20/45), or completely nonadherent patients (7/40 versus 4/45) to antihypertensive treatment were not different in the renal denervation and the control groups, respectively (P=0.3605). The difference in the change in daytime ambulatory systolic blood pressure from baseline to 6 months between the 2 groups was -6.7 mm Hg (P=0.0461) in fully adherent and -7.8 mm Hg (P=0.0996) in nonadherent (partially nonadherent plus completely nonadherent) patients. The between-patient variability of daytime ambulatory systolic blood pressure was greater for nonadherent than for fully adherent patients. In the DENERHTN trial, the prevalence of nonadherence to antihypertensive drugs at 6 months was high (≈50%) but not different in the renal denervation and control groups. Regardless of adherence to treatment, renal denervation plus standardized stepped-care antihypertensive treatment resulted in a greater decrease in blood pressure than standardized stepped-care antihypertensive treatment alone. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01570777.

Prevalence of orthostatic hypotension in non-institutionalised elderly aged 80 and over. A diagnostic study using an oscillometric device

BackgroundOrthostatic hypotension (OH) is a common disorder, and possibly underdiagnosed. In the elderly, OH has been considered a common cause of falls, fractures, and fear of falling. Its prevalence increases with age, probably related to the number of drug treatments, decreased fluid intake, and the progressive dysfunction of the autonomic nervous system. ObjectivesTo evaluate the prevalence of OH in a non-institutionalised population ≥80 years, according to different criteria based on sequential measurements taken at minute 0, 1, 3 and 5 of standing. Methods designA diagnostic accuracy study using an oscillometric device. Setting and participantsConvenience sampling of 176 people ≥80 years attended in an urban Primary Health Care Centre. MeasurementsSupine and standing blood pressure (BP) measurements, at minutes 0, 1, 3 and 5 using the OMRON 705-CP blood pressure device. OH definition: decrease ≥20mmHg in systolic BP (SBP) and/or ≥10mmHg in diastolic BP (DBP). ResultsMean age (Standard Deviation) was 85.2 (3.7) years, and 60.2% were women. Prevalence of OH: 30.7% at minute 0; 19.3% at minute 1; 18.2% at minute 3; and 20.5% at minute 5. Age, sedentary life, smoking, diabetes and SBP values were significantly associated with a greater BP decrease at minute 0. ConclusionA third of the sample had OH, with a maximum prevalence at minute 0. From a clinical point of view, it is suggested that the definition of OH is prioritized according to the BP at minute 0.

Blood Pressure Reduction in the Acute Phase of an Ischemic Stroke Does Not Improve Short- or Long-Term Dependency or Mortality: A Meta-Analysis of Current Literature.

The purpose of this study was to perform a meta-analysis of current literature to determine whether lowering blood pressure (BP) during the acute phase of an ischemic stroke improves short- and long-term outcomes.PubMed, Cochrane, and Embase were searched until September 5, 2014 using combinations of the search terms: blood pressure reduction, reduced blood pressure, lowering blood pressure, ischemic stroke, acute stroke, and intra-cerebral hemorrhage. Inclusion criteria were randomized controlled trial and patients with acute stroke (ischemic or hemorrhagic) treated with an antihypertensive agent or placebo. Outcome measures were change in systolic and diastolic BP (SBP, DBP) after treatment, and short- and long-term dependency and mortality rates.A total of 459 studies were identified, and ultimately 22 studies were included in the meta-analysis. The total number of participants in the treatment groups was 5672 (range, 6–2308), and in the control groups was 5416 (range, 6–2033). In most studies, more than 50% of the participants were males and the mean age was more than 60 years. The mean follow-up time ranged from 5 days to 12 months. As expected, treatment groups had a greater decrease in BP than control groups, and this effect was seen with different classes of antihypertensive drugs. Short-term and long-term dependency rates were similar between treatment and control groups (short-term dependency: pooled odds ratio [OR] = 1.041, 95% confidence interval [CI]: 0.936–1.159, P = 0.457; long-term dependency: pooled OR = 1.013, 95% CI: 0.915–1.120, P = 0.806). Short-term or long-term mortality was similar between the treatment and control groups (short-term mortality: pooled OR = 1.020, 95% CI: 0.749–1.388, P = .902; long-term mortality: pooled OR = 1.039, 95% CI: 0.883–1.222, P = 0.644).Antihypertensive agents effectively reduce BP during the acute phase of an ischemic stroke, but provide no benefit with respect to short- and long-term dependency and mortality.

"Vasovagal" response during ventricular fibrillation: incidence and implications.

The purpose of this study was to assess the relationship between changes in sinus node cycle length (SNCL) during ventricular fibrillation (VF) and the peripheral changes in blood pressure (BP) and sympathetic nerve activity (SNA) in human subjects. We hypothesized that patients with no SNCL shortening during VF have a vasovagal-like response with a greater decrease in BP and SNA when compared to patients with SNCL shortening. SNCL, BP, and SNA recordings were attempted in 24 patients undergoing the implantation of a dual-chamber implantable defibrillator. Changes were measured during the first 5 seconds of VF and compared with the 5 seconds prior to VF induction. SNCL shortened during VF in nine patients (mean%∆SNCL = -12 ± 8%) and remained unchanged or lengthened in seven patients (mean%∆SNCL = 7 ± 7%). Eight patients had ventriculoatrial (VA) conduction prohibiting assessment of SNCL changes. In patients with SNCL shortening, the %∆MBP (mean BP) was -47 ± 6% compared to -58 ± 8% in patients with no SNCL shortening (P < 0.01). In patients with VA conduction, the %∆MBP was -54 ± 3%. SNA recordings were successfully obtained in four patients. When compared to baseline, SNA increased by 34 ± 30% in two patients with SNCL shortening, decreased by 25% in one patient with SNCL lengthening, and by 90% in the fourth patient with VA conduction. We have shown that patients with no SNCL shortening have a significantly greater decrease in MBP during VF when compared to patients with SNCL shortening. The underlying mechanism appears to be reflex mediated with a vasovagal-like response in patients with no SNCL shortening.

Effects of Tyrosine on Parkinson's Disease: A Randomized, Double-Blind, Placebo-Controlled Trial.

Individuals with Parkinson's disease (PD) can suffer from orthostatic hypotension (OH) resulting from reduced levels of norepinephrine (NE), which inhibits the sympathetic nervous system. Levodopa reduces NE levels even further, leading to a greater decrease in blood pressure (BP) and increased OH. Tyrosine is a nonessential amino acid that is the major precursor to NE. Reduced levels of tyrosine have been shown after administration of l-dopa. This study was a single-center, randomized, double-blind, placebo-controlled trial to test the effects of supplementing l-tyrosine on BP, plasma tyrosine, NE levels, and autonomic responses to exercise in PD. Thirty-six subjects with PD receiving l-dopa medication that suffer from OH participated. Random assignment was to a placebo group or l-tyrosine 1,000mg (500mg of 2× daily) group for 7days. OH testing and exercise testing was performed pre- and postsupplementation. There was no effect of tyrosine on BP after OH testing postsupplementation (tyrosine, n=17; placebo, n=19). There was an increase in plasma tyrosine in the tyrosine group (P>0.05). There were no significant changes in any of the secondary outcome measures. l-tyrosine at 1,000mg (500mg/2× day) for 7days is safe and well tolerated in PD. Our results were inconclusive as to whether an increase in plasma tyrosine has an effect on OH in subjects with PD. An increase in plasma tyrosine had no effect on BP or autonomic responses in subjects with PD during acute exercise stress. (Trial registration: http://ClinicalTrials.gov.; identifier: NCT01676103).

Abstract 210: Impaired Brain-Derived Neurotrophic Factor-TrkB Signaling in Nucleus Tractus Solitarius During Chronic Heart Failure Blunts Baroreflex Sensitivity

Blunted baroreflex function is a negatively prognostic marker of autonomic imbalance in chronic heart failure (CHF), yet the mechanisms underlying baroreflex blunting in CHF are not fully understood. The nucleus tractus solitarius (NTS) is the primary central target of baroreceptor afferents, and plays a critical role in regulating central baroreflex sensitivity. Brain-derived neurotrophic factor (BDNF) and its receptor, TrkB, are highly expressed in the NTS, but little is known about the role of BDNF signaling in the NTS. We hypothesized that in the NTS, BDNF enhances baroreflex sensitivity, and impaired BDNF-TrkB signaling contributes to the blunted baroreflex function in CHF. To test this hypothesis, 50 nl of BDNF or the selective TrkB antagonist ANA-12 were microinjected bilaterally into the dorso-medial NTS of sham-operated rats and myocardial infarct-induced CHF rats. BDNF evoked a greater decrease in blood pressure (MAP), heart rate (HR), and renal sympathetic nerve activity (RSNA) in sham vs. CHF rats. Injection of ANA-12 increased MAP, HR, and RSNA to a greater extent in sham vs. CHF rats (Table). Following 125 μM ANA-12, baroreflex sensitivity was blunted in sham rats (3.7 ± 0.3 vs. 1.9 ± 0.1 bpm/mmHg max gain, p &lt; .05 before vs. after, n = 4). CHF rats had blunted baroreflex sensitivity vs. sham (2.3 ± 0.1 bpm/mmHg, p &lt; .05, n = 4), and ANA-12 had little effect on baroreflex sensitivity in CHF (2.0 ± 0.1 bpm/mmHg, n = 4). These data suggest that endogenous BDNF plays an important role in maintaining baroreflex sensitivity in the NTS, and that BDNF-TrkB signaling is impaired in CHF, which may contribute to blunted baroreflex sensitivity and autonomic imbalance.