0
selected
-
1.
Diagnosis of multiple system atrophy.
Palma, JA, Norcliffe-Kaufmann, L, Kaufmann, H
Autonomic neuroscience : basic & clinical. 2018;:15-25
-
-
Free full text
-
Abstract
Multiple system atrophy (MSA) may be difficult to distinguish clinically from other disorders, particularly in the early stages of the disease. An autonomic-only presentation can be indistinguishable from pure autonomic failure. Patients presenting with parkinsonism may be misdiagnosed as having Parkinson disease. Patients presenting with the cerebellar phenotype of MSA can mimic other adult-onset ataxias due to alcohol, chemotherapeutic agents, lead, lithium, and toluene, or vitamin E deficiency, as well as paraneoplastic, autoimmune, or genetic ataxias. A careful medical history and meticulous neurological examination remain the cornerstone for the accurate diagnosis of MSA. Ancillary investigations are helpful to support the diagnosis, rule out potential mimics, and define therapeutic strategies. This review summarizes diagnostic investigations useful in the differential diagnosis of patients with suspected MSA. Currently used techniques include structural and functional brain imaging, cardiac sympathetic imaging, cardiovascular autonomic testing, olfactory testing, sleep study, urological evaluation, and dysphagia and cognitive assessments. Despite advances in the diagnostic tools for MSA in recent years and the availability of consensus criteria for clinical diagnosis, the diagnostic accuracy of MSA remains sub-optimal. As other diagnostic tools emerge, including skin biopsy, retinal biomarkers, blood and cerebrospinal fluid biomarkers, and advanced genetic testing, a more accurate and earlier recognition of MSA should be possible, even in the prodromal stages. This has important implications as misdiagnosis can result in inappropriate treatment, patient and family distress, and erroneous eligibility for clinical trials of disease-modifying drugs.
-
2.
Autonomic nervous system dysfunction: implication in sickle cell disease.
Connes, P, Coates, TD
Comptes rendus biologies. 2013;(3):142-7
Abstract
Sickle cell disease is an inherited hemoglobinopathy caused by a single amino acid substitution in the β chain of hemoglobin that causes the hemoglobin to polymerize in the deoxy state. The resulting rigid, sickle-shaped red cells obstruct blood flow causing hemolytic anemia, tissue damage, and premature death. Hemolysis is continual. However, acute exacerbations of sickling called vaso-occlusive crises (VOC) resulting in severe pain occur, often requiring hospitalization. Blood rheology, adhesion of cellular elements of blood to vascular endothelium, inflammation, and activation of coagulation decrease microvascular flow and increase likelihood of VOC. What triggers the transition from steady state to VOC is unknown. This review discusses the interaction of blood rheological factors and the role that autonomic nervous system (ANS) induced vasoconstriction may have in triggering crisis as well as the mechanism of ANS dysfunction in SCD.
-
3.
Cardiovascular and autonomic modulation by the central nervous system after aerobic exercise training.
Martins-Pinge, MC
Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas. 2011;(9):848-54
Abstract
The autonomic nervous system plays a key role in maintaining homeostasis under normal and pathological conditions. The sympathetic tone, particularly for the cardiovascular system, is generated by sympathetic discharges originating in specific areas of the brainstem. Aerobic exercise training promotes several cardiovascular adjustments that are influenced by the central areas involved in the output of the autonomic nervous system. In this review, we emphasize the studies that investigate aerobic exercise training protocols to identify the cardiovascular adaptations that may be the result of central nervous system plasticity due to chronic exercise. The focus of our study is on some groups of neurons involved in sympathetic regulation. They include the nucleus tractus solitarii, caudal ventrolateral medulla and the rostral ventrolateral medulla that maintain and regulate the cardiac and vascular autonomic tonus. We also discuss studies that demonstrate the involvement of supramedullary areas in exercise training modulation, with emphasis on the paraventricular nucleus of the hypothalamus, an important area of integration for autonomic and neuroendocrine responses. The results of these studies suggest that the beneficial effects of physical activity may be due, at least in part, to reductions in sympathetic nervous system activity. Conversely, with the recent association of physical inactivity with chronic disease, these data may also suggest that increases in sympathetic nervous system activity contribute to the increased incidence of cardiovascular diseases associated with a sedentary lifestyle.
-
4.
Gastrointestinal influence on the electrophysiology of the heart: induction of cardiac arrhythmic episodes by myoelectrical uncoupling within the gut.
Powers, D
Journal of smooth muscle research = Nihon Heikatsukin Gakkai kikanshi. 2009;(4):139-48
Abstract
It is theorized that the triggering of some arrhythmic episodes in cardiac-sensitive subjects might be directly linked to the functional uncoupling of gastro myoelectrical activity following the consumption of particular foods or by other influences on the gut. The intent of this research is to reveal the likely adverse mechanism involved through investigative analytical review. The resulting evidence shows there exists a triggering source within the visceral smooth muscle system of the gut and a mode of transmission incorporated in the autonomic nervous system mediated by the central autonomic network that could significantly affect the electrophysiology of the heart. A formal clinical study is indicated to determine the specific types of troublesome foods and other factors associated to better understand the overall process.
-
5.
Functional findings in irritable bowel syndrome.
Posserud, I, Ersryd, A, Simrén, M
World journal of gastroenterology. 2006;(18):2830-8
Abstract
The pathophysiology of IBS is complex and still incompletely known. Both central and peripheral factors, including psychosocial factors, abnormal GI motility and secretion, and visceral hypersensitivity, are thought to contribute to the symptoms of IBS. Several studies have demonstrated altered GI motor function in IBS patients and the pattern differs between IBS subgroups based on the predominant bowel pattern. Few studies have so far addressed GI secretion in IBS, but there are some evidence supporting altered secretion in the small intestine of IBS patients. Visceral hypersensitivity is currently considered to be perhaps the most important pathophysiological factor in IBS. Importantly, several external and internal factors can modulate visceral sensitivity, as well as GI motility, and enhanced responsiveness within the GI tract to for instance stress and nutrients has been demonstrated in IBS patients. Today IBS is viewed upon as a disorder of dysregulation of the so-called brain-gut axis, involving abnormal function in the enteric, autonomic and/or central nervous systems, with peripheral alterations probably dominating in some patients and disturbed central processing of signals from the periphery in others.
-
6.
Is it time for cardiac innervation imaging?
Knuuti, J, Sipola, P
The quarterly journal of nuclear medicine and molecular imaging : official publication of the Italian Association of Nuclear Medicine (AIMN) [and] the International Association of Radiopharmacology (IAR), [and] Section of the Society of.... 2005;(1):97-105
Abstract
The autonomic nervous system plays an important role in the regulation of cardiac function and the regional distribution of cardiac nerve terminals can be visualized using scintigraphic techniques. The most commonly used tracer is iodine-123-metaiodobenzylguanidine (MIBG) but C-11-hydroxyephedrine has also been used with PET. When imaging with MIBG, the ratio of heart-to-mediastinal counts is used as an index of tracer uptake, and regional distribution is also assessed from tomographic images. The rate of clearance of the tracer can also be measured and indicates the function of the adrenergic system. Innervation imaging has been applied in patients with susceptibility to arrhythmias, coronary artery disease, hypertrophic and dilated cardiomyopathy and anthracycline induced cardiotoxicity. Abnormal adrenergic innervation or function appear to exist in many pathophysiological conditions indicating that sympathetic neurons are very susceptible to damage. Abnormal findings in innervation imaging also appear to have significant prognostic value especially in patients with cardiomyopathy. Recently, it has also been shown that innervation imaging can monitor drug-induced changes in cardiac adrenergic activity. Although innervation imaging holds great promise for clinical use, the method has not received wider clinical acceptance. Larger randomized studies are required to confirm the value of innervation imaging in various specific indications.
-
7.
Blood pressure and cardiac autonomic function in relation to risk factors and treatment perspectives in Type 1 diabetes.
Poulsen, PL
Journal of the renin-angiotensin-aldosterone system : JRAAS. 2002;(4):222-42
Abstract
The cumulative incidence of diabetic nephropathy in Type 1 diabetes mellitus is in the order of 25 30%. The recognition that elevated blood pressure (BP) is a major factor in the progression of these patients to end-stage renal failure has led to the widespread use of antihypertensive therapy in order to preserve glomerular filtration rate and ultimately to reduce mortality. The routine measurement of microalbuminuria allows early identification of the subgroup of patients at increased risk of developing clinical nephropathy. Microalbuminuric Type 1 diabetic patients show a number of characteristic pathological abnormalities. In addition to elevated BP and abnormal circadian rhythm, there are also associated abnormalities of vagal function, lipid profile and endothelial function, as well as an increased prevalence of retinopathy. The first section of this two-part review focusses on the early changes associated with renal involvement in Type 1 diabetes. It addresses the associations between urinary albumin excretion, glycaemic control, smoking, BP, circadian BP variation, QT interval abnormalities and autonomic function in three groups of patients; those with normoalbuminuria, those progressing towards microalbuminuria and those with established low-grade microalbuminuria.