Direct evidence of sympathetic hyperactivity in patients with vasospastic angina.

Background: The autonomic nervous system is reported to be involved in the pathogenesis of vasospastic angina (VSA). Studies based on heart rate variability analysis have shown conflicting results with both a reduction and an enhancement of sympathetic nervous system (SNS) activity in patients with Prinzmetal's variant angina, but direct assessment has never been performed. The aim of our study was to evaluate the SNS activity using microneurography in patients with VSA.

Direct evidences for sympathetic hyperactivity and baroreflex impairment in Tako Tsubo cardiopathy.

Background: The exact pathophysiology of Tako-Tsubo cardiomyopathy (TTC) remains unknown but a role for sympathetic hyperactivity has been suggested. Up to now, no direct evidence of sympathetic nerve hyperactivity has been established nor involvement of sympathetic baroreflex identified. The aim of our study was to determine, by direct sympathetic nerve activity (SNS) recording if sympathetic nervous system activity is increased and spontaneous baroreflex control of sympathetic activity reduced in patients with TTC.

Towards a less invasive approach to the early goal-directed treatment of septic shock in the ED.

Introduction: Early goal-directed therapy (EGDT) in septic shock defined by Rivers et al was proven to reduce mortality and validated by observational studies. However, criticism is centered in particular on the early requirement of a central venous catheter (CVC) and on central venous pressure (CVP) as an indicator of volume responsiveness. The present study is a pivotal study to investigate the reliability of a less invasive approach, which uses inferior vena cava (IVC) and lung ultrasounds (US) to guide the infusion of fluids and lactate clearance to monitor tissue perfusion.

Transcatheter aortic valve implantation reduces sympathetic activity and normalizes arterial spontaneous baroreflex in patients with aortic stenosis.

Objectives: This study sought to measure muscle sympathetic nerve activity (MSNA) in patients with aortic stenosis (AS) before and after transcatheter aortic valve implantation (TAVI) and to compare MSNA with that of control patients.

Background: TAVI is an emerging therapeutic option in patients with severe AS at high risk of open heart surgery. Whether patients with AS have increased sympathetic activity remains to be established, and the effects of TAVI on the sympathetic nervous system are also unknown.

High-intensity interval exercise improves vagal tone and decreases arrhythmias in chronic heart failure.

Purpose: Autonomic dysfunction including sympathetic activation and vagal withdrawal has been reported in patients with chronic heart failure (CHF). We tested the hypotheses that high-intensity interval exercise (HIIE) in CHF patients would enhance vagal modulation and thus decrease arrhythmic events.

Methods: Eighteen CHF patients underwent a baseline assessment (CON) and were then randomized to a single session of HIIE and to an isocaloric moderate-intensity continuous exercise (MICE).

Cardiorenal anemia syndrome in chronic heart failure contributes to increased sympathetic nerve activity.

Background: We sought to assess whether cardiorenal anemia syndrome (CRAS) in chronic heart failure (CHF) patients contributes to sympathetic overactivity through modulation of sympathetic reflexes.

Methods And Results: We prospectively studied 15 patients with CRAS and CHF and 15 control CHF patients, matched for age, gender distribution, type of cardiomyopathy, left ventricular ejection fraction (LVEF) and BMI. We compared muscle sympathetic nerve activity (MSNA) and the effect of peripheral chemoreflex deactivation on MSNA in both groups.