Endovascular baroreflex amplification and the effect on sympathetic nerve activity in patients with resistant hypertension: A proof-of-principle study.

Background: First in human studies suggest that endovascular baroreflex amplification (EVBA) lowers blood pressure (BP). To explore potential mechanisms for BP reduction, this study examines the effects of EVBA on muscle sympathetic nerve activity (MSNA) and baroreceptor sensitivity (BRS).

Methods: In a single-center sub-study of the CALM-DIEM study (Controlling And Lowering blood pressure with the MobiusHD-Defining Efficacy Markers), 14 patients with resistant hypertension were treated with EVBA.

Heart rate variability in intensive care unit patients with delirium.

Sympathovagal balance, assessed with heart rate variability (HRV), may be altered in intensive care unit (ICU) delirium. HRV was measured in the frequency domain [low frequencies (LF)=0.04-0.

Differential effects of renin-angiotensin-aldosterone system inhibition, sympathoinhibition and diuretic therapy on endothelial function and blood pressure in obesity-related hypertension: a double-blind, placebo-controlled cross-over trial.

Objectives: The objective of this study is to determine the effects of renin-angiotensin-aldosterone system inhibition, sympathoinhibition and diuretic therapy on endothelial function and blood pressure in obesity-related hypertension.

Methods: A randomized, four-way, double-blind, crossover study in 31 adults with previously untreated obesity-related hypertension, in which the effects of 8 weeks' inhibition of the renin-angiotensin-aldosterone system (using aliskiren 300 mg), sympathoinhibition (using moxonidine 0.4 mg), diuretic therapy (using hydrochlorothiazide 25 mg) or placebo on flow-mediated dilation and 24-h blood pressure were compared.

Intramedullary femoral nailing through the trochanteric fossa versus greater trochanter tip: a randomized controlled study with in-depth functional outcome results.

Purpose: In a level 1 university trauma center, an explorative randomized controlled study was performed to compare soft tissue damage and functional outcome after antegrade femoral nailing through a trochanteric fossa (also known as piriform fossa) entry point to a greater trochanter entry point in patients with a femoral shaft fracture.

Materials And Methods: Nineteen patients were enrolled and randomly assigned to two nail insertion groups; ten patients were treated with an Unreamed Femoral Nail(®) (UFN, Synthes(®), Solothurn, Switzerland) inserted at the trochanteric fossa and nine patients were treated with an Antegrade Femoral Nail(®) (AFN, Synthes(®), Solothurn, Switzerland) inserted at the tip of the greater trochanter. The main outcome measures were pain, gait, nerve and muscle function, along with endurance.

Atorvastatin reduces sympathetic activity in patients with chronic kidney disease.

Background: Hypertensive chronic kidney disease (CKD) patients often have sympathetic hyperactivity, which appears to contribute to the pathogenesis of hypertension and cardiovascular organ damage. Experimental studies and some clinical studies have shown that statin therapy can reduce central sympathetic activity. Blockade of the renin-angiotensin system (RAS), which is standard treatment for CKD, is known to lower sympathetic activity.

Aliskiren reduces sympathetic nerve activity and blood pressure in chronic kidney disease patients.

Background: Hypertensive chronic kidney disease (CKD) patients often have sympathetic hyperactivity. In this pilot study, we evaluated the effect of 6 weeks treatment with aliskiren on sympathetic activity in hypertensive Stages 2-4 CKD patients.

Methods: In 10 CKD patients (8 males, aged 44 ± 11 years, estimated glomerular filtration rate ( 57 ± 22 mL/min/1.

Postprandial hypotension in clinical geriatric patients and healthy elderly: prevalence related to patient selection and diagnostic criteria.

The aims of this study were to find out whether Postprandial hypotension (PPH) occurs more frequently in patients admitted to a geriatric ward than in healthy elderly individuals, what the optimal interval between blood pressure measurements is in order to diagnose PPH and how often it is associated with symptoms.The result of this study indicates that PPH is present in a high number of frail elderly, but also in a few healthy older persons. Measuring blood pressure at least every 10 minutes for 60 minutes after breakfast will adequately diagnose PPH, defined as >20 mmHg systolic fall, in most patients.

Small-fibre neuropathy can be detected in patients with chronic idiopathic axonal polyneuropathy.

Background: The main sensory presenting symptoms of chronic idiopathic axonal polyneuropathy (CIAP) are paraesthesias, numbness and burning pain in the feet. Although these symptoms indicate the involvement of small nerve fibres, clinical analysis or electrophysiological investigations have not yet been studied in detail.

Method: Cardiovascular autonomic tests and cold and heat pain perception threshold tests were performed in 10 patients with CIAP, 10 patients with diabetes mellitus (DM) and 10 healthy volunteers.

Differential effects of acute and sustained cyclosporine and tacrolimus on sympathetic nerve activity.

Background: We studied the effect of acute and sustained cyclosporine and tacrolimus on muscle sympathetic nerve activity (MSNA) in groups of healthy male volunteers.

Methods And Results: Acute cyclosporine in normal dose (2.5 mg/kg) increased MSNA from 11 +/- 6 to 19 +/- 8 bursts/min (P < 0.

Sympathetic activity in chronic kidney disease patients is related to left ventricular mass despite antihypertensive treatment.

Background: Chronic kidney disease (CKD) patients often have sympathetic hyperactivity, which contributes to the pathogenesis of hypertension and cardiovascular organ damage. Angiotensin-converting enzyme (ACE) inhibitors (ACEi) and angiotensin II receptor blockers (ARB) reduce sympathetic hyperactivity. Ideally, treatment should eliminate the relation between sympathetic activity and organ damage.

Sympathetic hyperactivity and clinical outcome in chronic kidney disease patients during standard treatment.

Background: Sympathetic hyperactivity has been associated with adverse clinical outcome and is common in patients with chronic kidney disease (CKD). Angiotensin-converting enzyme inhibitors (ACEi) and angiotensin II receptor blockers (ARB) have been shown to reduce sympathetic activity in CKD patients. The present study was performed to investigate whether sympathetic hyperactivity was related to clinical outcome in CKD patients treated with ACEi or ARB.

Short-term sympathetic baroreflex sensitivity increases at lower blood pressures.

Objective: Sympathetic baroreflex sensitivity (symBRS) can be defined as the maximum sensitivity of muscle sympathetic nerve activity (MSNA) to changes in arterial blood pressure. This sensitivity is the slope of the linear middle part of the sigmoid curve that relates blood pressure to MSNA. SymBRS is known to vary with conditions, for instance during cold pressor testing.

The effect of intraduodenal glucose on muscle sympathetic nerve activity in healthy young and older subjects.

Objective: The cardiovascular response to a meal is modulated by gastric distension and the interaction of nutrients, particularly carbohydrate, within the small intestine. We tested the hypothesis that the depressor effect of small intestinal glucose is greater in older than in young subjects, because the reflex increase in muscle sympathetic nerve activity (MSNA) is blunted by age.

Methods: The effects of intraduodenal glucose infusion (IDGI) on blood pressure, heart rate and MSNA were evaluated in eight healthy young subjects (4 women; mean age +/- SEM: 28.

Sympathetic hyperactivity in haemodialysis patients is reduced by short daily haemodialysis.

Objective: Haemodialysis patients often have sympathetic hyperactivity. The hypothesis of this study was that a switch from three times weekly to short daily dialysis could affect sympathetic hyperactivity.

Methods: We studied 11 patients (eight men; aged 46 +/- 8 years) stable on haemodialysis for at least 1 year before and 6 months after conversion from three times to six times weekly dialysis without increasing total dialysis time (short daily dialysis).

Function of the clavicular part of the pectoralis major muscle after transplantation of its sternocostal part.

Background: Muscle-sparing transplantation of the sternocostal part of the pectoralis major muscle while preserving the clavicular part of the muscle may reduce donor-site morbidity, particularly in cases where dissection of the lymph nodes of the neck has been performed. The nerve supply and motor function of the clavicular part is alleged to be preserved when the sternocostal part is transposed through the deltopectoral groove. This study aims to objectify such preservation.

Sympathetic hyperactivity in hypertensive chronic kidney disease patients is reduced during standard treatment.

Standard treatment in chronic kidney disease (CKD) patients includes an angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker. CKD is often characterized by sympathetic hyperactivity. This study investigates the prevalence of sympathetic hyperactivity (quantified by assessment of muscle sympathetic nerve activity [MSNA]) in a sizable group of patients with CKD and assessed whether chronic angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker normalizes increased MSNA.

Subtle involvement of the parasympathetic nervous system in patients with irritable bowel syndrome.

This study comprises assessment of autonomic function in irritable bowel syndrome (IBS) patients, focusing on meal-related changes. In 18 IBS patients (4 males, mean age 45+/-3.0 [SEM] years) and 19 healthy volunteers (6 males, mean age 41+/-3.

Effect of gastric distension on cardiovascular parameters: gastrovascular reflex is attenuated in the elderly.

Stretching the stomach wall in young healthy subjects causes an increase in muscle sympathetic nerve activity and in blood pressure, the gastrovascular reflex. We compared healthy elderly subjects with healthy young subjects to find out whether the gastrovascular reflex attenuates in normal ageing and we studied whether there was a difference in autonomic function or gastric compliance that could explain this possible attenuation. Muscle sympathetic nerve activity, finger blood pressure and heart rate were continuously recorded during stepwise isobaric gastric distension using a barostat in eight healthy young (6 men and 2 women, 27 +/- 3.

Sympathetic nerve activity is inappropriately increased in chronic renal disease.

The hypothesis that in hypertensive patients with renal parenchymal disease sympathetic activity is "inappropriately" elevated and that this overactivity is a feature of renal disease and not of a reduced number of nephrons per se is addressed. Fifty seven patients with renal disease (various causes, no diabetes, all on antihypertensive medication) were studied, age range 18 to 62, creatinine clearance 10 to 114 ml/min per 1.73 m(2).

Enalapril and losartan reduce sympathetic hyperactivity in patients with chronic renal failure.

The aim of this study was to compare the effects on BP and sympathetic activity of chronic treatment with an angiotensin (Ang)-converting enzyme (ACE) inhibitor and an AngII receptor blocker in hypertensive patients with chronic renal failure (CRF). In ten stable hypertensive CRF patients (creatinine clearance, 46 +/- 17 ml/min per 1.73 m(2)), muscle sympathetic nerve activity (MSNA), plasma renin activity (PRA), baroreceptor sensitivity, and 24-h ambulatory BP were measured in the absence of antihypertensive drugs (except diuretics) after 6 wk of enalapril (10 mg orally) and after 6 wk of losartan (100 mg orally).

Subtle involvement of the sympathetic nervous system in amyotrophic lateral sclerosis.

The literature on the involvement of the autonomic nervous system (ANS) in amyotrophic lateral sclerosis (ALS) is conflicting. We therefore investigated several aspects of autonomic function, namely muscle sympathetic nerve activity (MSNA), blood pressure, cardiac function (electrocardiogram; ECG), and respiration in 16 patients with sporadic ALS and in 12 age-matched healthy volunteers, both at rest and during sympathoexcitatory stimulation. We measured MSNA by provoking venous pooling during short-lasting lower body negative pressure (LBNP) and during the cold pressor test (CPT).

Sympathetic activity is increased in polycystic kidney disease and is associated with hypertension.

Hypertension is common in patients with polycystic kidney disease (PKD). This study addresses the hypothesis that sympathetic activity is enhanced in hypertensive PKD patients, not only when renal function is impaired but also when renal function is still normal. Muscle sympathetic nerve activity (MSNA, peroneal nerve), plasma renin activity (PRA), heart rate, and BP were studied in PKD patients with normal and with impaired renal function and in matched controls.

Observer variations in short period spectral analysis of heart rate variability.

25% of the corresponding mean LF/HF ratio. The smallest interobserver variations were found for the 'fixed frequency' method. The data showed that it is advantageous to select the 3-min ECG periods but not to select the frequency regions.

Autonomic function in patients with hereditary motor and sensory neuropathy type I and Lambert-Eaton myasthenic syndrome.

Noninvasive tests of four autonomic organ systems (vasomotor control, baroreceptor reflexes, sudomotor function and pupillary reflexes) were performed on nine patients with hereditary motor and sensory neuropathy (HMSN) type I and three patients with Lambert-Eaton myasthenic syndrome (LEMS). The results were compared with those of 33 control subjects. Autonomic dysfunction was considered present when at least two of the four organ system tests were abnormal.