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Exercise Intolerance (exercise + intolerance)
Selected AbstractsLeft Coronary Artery Arteriovenous Malformation Presenting as a Diastolic Murmur with Exercise Intolerance in a Child with a Suspected Familial Vascular Malformation SyndromeCONGENITAL HEART DISEASE, Issue 3 2007Valerie A. Schroeder MD Abstract Objective., Intracardiac arteriovenous malformations are rare and may be associated with sudden death in adults. This case report describes an intracardiac left coronary arteriovenous malformation in a 7-year-old boy with a suspected familial cutaneous vascular malformation syndrome. The patient presented with a diastolic murmur, exercise intolerance, chest pain, and a left ventricular mass. Methods., The left ventricular mass was initially identified by echocardiography. Subsequently, a computed tomography scan revealed the vascular nature of the lesion. We hypothesized that the lesion represented either an arteriovenous malformation (AVM) or a hemangioma. These lesions are thought to cause coronary steal and myocardial dysfunction. Skin biopsies of the patient's cutaneous lesions revealed capillary hyperplasia, which was not consistent with either hemangioma or AVM. Thus, a surgical biopsy and partial resection of the mass was performed. Results., The surgical pathology of the cardiac mass was consistent with an AVM. Within 6 months following partial resection of the mass, the patient unexpectedly developed a left ventricular pseudoaneurysm at the resection site and required re-operation. Although a portion of the mass remains, both the patient's chest pain and exercise tolerance have improved subjectively. Conclusion., Patients with cutaneous vascular malformations and diastolic murmurs, as well as cardiac symptoms, should undergo echocardiography or alternative imaging modalities to screen for treatable pathological myocardial vascular malformations. [source] Pulmonary Function and Ventilatory Limitation to Exercise in Congenital Heart DiseaseCONGENITAL HEART DISEASE, Issue 1 2009Paolo T. Pianosi MD ABSTRACT Pulmonary function in older children and adolescents following surgical repair of congenital heart disease is often abnormal for various reasons. Many of these patients report symptoms of exercise intolerance although the reason(s) for this symptom can be complicated and sometimes interrelated. Is it simply deconditioning due to inactive lifestyle, chronotropic or inotropic insufficiency? or could there indeed be ventilatory limitation to exercise? These are the questions facing the clinician with the increasing frequency of patients undergoing repair early in life and growing into adulthood. Understanding pulmonary functional outcomes and means of determining ventilatory limitation to exercise is essential to thoroughly address the problem. This article reviews pulmonary function in patients with congenital heart disease and then describes a newer technique that should be applied to determine ventilatory limitation to exercise. [source] Pulmonary Regurgitation after Tetralogy of Fallot Repair: Clinical Features, Sequelae, and Timing of Pulmonary Valve ReplacementCONGENITAL HEART DISEASE, Issue 6 2007Naser M. Ammash MD ABSTRACT Pulmonary regurgitation following repair of tetralogy of Fallot is a common postoperative sequela associated with progressive right ventricular enlargement, dysfunction, and is an important determinant of late morbidity and mortality. Although pulmonary regurgitation may be well tolerated for many years following surgery, it can be associated with progressive exercise intolerance, heart failure, tachyarrhythmia, and late sudden death. It also often necessitates re-intervention. Identifying the appropriate timing of such intervention could be very challenging given the risk of prosthetic valve degeneration and the increased risk of reoperation. Comprehensive informed and regular assessment of the postoperative patient with tetralogy of Fallot, including evaluation of pulmonary regurgitation, right heart structure and function, is crucial to the optimal care of these patients. Pulmonary valve replacement performed in an experienced tertiary referral center is associated with low operative morbidity and mortality and very good long-term results. Early results of percutaneous pulmonary valve replacement are also promising. [source] Left Coronary Artery Arteriovenous Malformation Presenting as a Diastolic Murmur with Exercise Intolerance in a Child with a Suspected Familial Vascular Malformation SyndromeCONGENITAL HEART DISEASE, Issue 3 2007Valerie A. Schroeder MD Abstract Objective., Intracardiac arteriovenous malformations are rare and may be associated with sudden death in adults. This case report describes an intracardiac left coronary arteriovenous malformation in a 7-year-old boy with a suspected familial cutaneous vascular malformation syndrome. The patient presented with a diastolic murmur, exercise intolerance, chest pain, and a left ventricular mass. Methods., The left ventricular mass was initially identified by echocardiography. Subsequently, a computed tomography scan revealed the vascular nature of the lesion. We hypothesized that the lesion represented either an arteriovenous malformation (AVM) or a hemangioma. These lesions are thought to cause coronary steal and myocardial dysfunction. Skin biopsies of the patient's cutaneous lesions revealed capillary hyperplasia, which was not consistent with either hemangioma or AVM. Thus, a surgical biopsy and partial resection of the mass was performed. Results., The surgical pathology of the cardiac mass was consistent with an AVM. Within 6 months following partial resection of the mass, the patient unexpectedly developed a left ventricular pseudoaneurysm at the resection site and required re-operation. Although a portion of the mass remains, both the patient's chest pain and exercise tolerance have improved subjectively. Conclusion., Patients with cutaneous vascular malformations and diastolic murmurs, as well as cardiac symptoms, should undergo echocardiography or alternative imaging modalities to screen for treatable pathological myocardial vascular malformations. [source] Critical Left Ventricular Outflow Tract Obstruction Due to Accessory Mitral Valve TissueECHOCARDIOGRAPHY, Issue 2 2000RAFFAELE CALABRO M.D. Left ventricular outflow tract (LVOT) obstruction due to anomalous tissue tag arising from the mitral valve is a rare congenital cardiac anomaly. It generally becomes symptomatic during the first decade of life as exercise intolerance, chest pain, or syncope at effort. To date, only a few cases of critical systemic obstruction due to isolated mitral valve anomaly in neonates have been reported. We report the case of a neonate who was a few hours old and was referred in severe clinical condition due to critical left ventricular outflow obstruction resulting from an anomalous tissue tag of mitral valve origin. [source] Effects of stylopharyngeus muscle dysfunction on the nasopharynx in exercising horsesEQUINE VETERINARY JOURNAL, Issue 4 2004C. TESSIER Summary Reasons for performing study: Nasopharyngeal collapse has been observed in horses as a potential cause of exercise intolerance and upper respiratory noise. No treatment is currently available and affected horses are often retired from performance. Objective: To determine the effect of bilateral glossopharyngeal nerve block and stylopharyngeus muscle dysfunction on nasopharyngeal function and airway pressures in exercising horses. Methods: Endoscopic examinations were performed on horses at rest and while running on a treadmill at speeds corresponding to HRmax50, HRmax75 and HRmax, with upper airway pressures measured with and without bilateral glossopharyngeal nerve block. Results: Bilateral glossopharyngeal nerve block caused stylopharyngeus muscle dysfunction and dorsal nasopharyngeal collapse in all horses. Peak inspiratory upper airway pressure was significantly (P = 0.0069) more negative at all speeds and respiratory frequency was lower (P = 0.017) in horses with bilateral glossopharyngeal nerve block and stylopharyngeus muscle dysfunction compared to control values. Conclusions: Bilateral glossopharyngeal nerve anaesthesia produced stylopharyngeus muscle dysfunction, dorsal pharyngeal collapse and airway obstruction in all horses. Potential relevance: The stylopharyngeus muscle is probably an important nasopharyngeal dilating muscle in horses and dysfunction of this muscle may be implicated in clinical cases of dorsal nasopharyngeal collapse. Before this information can be clinically useful, further research on the possible aetiology of stylopharyngeus dysfunction and dysfunction of other muscles that dilate the dorsal and lateral walls of the nasopharynx in horses is needed. [source] Inherited myopathy of great DanesJOURNAL OF SMALL ANIMAL PRACTICE, Issue 5 2006A. Lujan Feliu-Pascual A hereditary, non-inflammatory myopathy occurring in young great Danes with distinctive histological features in muscle biopsy specimens is reviewed. Onset of clinical signs is usually before one year of age and both sexes are affected. Clinical signs are characterised by exercise intolerance, muscle wasting, and an exercise-induced tremor. Although most affected dogs have a severe form of the disease, occasional dogs may have a less pronounced form and survive into adulthood with an acceptable quality of life. Litters containing affected puppies are born to clinically unaffected parents, and an autosomal recessive pattern of inheritance is likely. All recorded cases have had fawn or brindle coat coloration. Elevated serum creatinine kinase concentrations and spontaneous electrical activity in skeletal muscles are frequently found. While originally reported (Targett and others 1994) as a central core myopathy in this breed, the histochemical characteristics of the distinct cytoarchitectural structures differ from those of the well-characterised central core myopathy in human beings. In fact, these structures differ from any known myopathy in human beings and likely represents a unique non-inflammatory myopathy affecting dogs. Until this myopathy is characterised further, the name inherited myopathy in great Danes is suggested. [source] Management of cor triatriatum dexter by balloon dilatation in three dogsJOURNAL OF SMALL ANIMAL PRACTICE, Issue 1 2004M. Stafford Johnson Two dogs, one immature and one adult, were presented with a history of progressive ascites. In a third, immature dog, increasing exercise intolerance had been noted. Echocardiography demonstrated a partition in the right atrium (cor triatriatum dexter) and echocontrast studies documented normal flow from the cranial vena cava into the right atrium and ventricle. A saphenous vein contrast study demonstrated flow from the caudal vena cava into an accessory right atrial chamber (sinus venarum). The sinus venarum communicated with the true right atrium via a small defect in the atrial membrane in one dog, and additionally with the left atrium via a right-to- left shunting foramen ovale in the other dogs. All defects were visualised on angiographic studies by selective catheterisation of the caudal vena cava via the femoral vein. Balloon dilatation of the defect was then performed using a small followed by a larger balloon angioplasty catheter to enlarge the defect in the atrial membrane. Clinical signs improved within days and were sustained in the long term in all cases. [source] Double Chambered Right Ventricle in 9 CatsJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2007H. Koffas Background: Double-chambered right ventricle (DCRV) is a frequently recognized cardiac congenital abnormality in humans. It has been described in dogs and in 1 cat. However systemic description of clinical and echocardiographic features of the disease in cats is currently lacking from the veterinary literature. Animals: Nine cats with DCRV are described. Results: The cats ranged from 4 months to 10 years of age. Eight cats at presentation were asymptomatic and 1 cat had chylothorax. In all cases echocardiography revealed abnormal fibromuscular bundles obstructing the mid-right ventricle, dividing the chamber into 2 compartments. The proximal right ventricular compartment was markedly hypertrophied, and right atrial dilation was usually present. The mean pressure gradient measured across the stenotic area was 130 ± 50 mm Hg. Concurrent abnormalities included a ventricular septal defect (n = 2); aortic malalignment, aortic insufficiency (n = 1); and congenital peritoneal-pericardial diaphragmatic hernia (n = 1). Two cats had systolic anterior motion of the mitral valve, one of which had concurrent left ventricular hypertrophy. Five cats have remained asymptomatic for a median period of 3.6 years (range, 3.3,5 years) and 3 cats have developed clinical signs associated with congestive heart failure (at 2, 3.3, and 9 years). One cat showed progressive lethargy and exercise intolerance and underwent partial ventriculectomy at the age of 2 years. This cat died during the operation with electromechanical dissociation. Conclusions: DCRV is a congenital cardiac abnormality that may be more common than previously recognized. [source] Muscular Dystrophy in female DogsJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 3 2001G. Diane Shelton The most common form of muscular dystrophy in dogs and humans is caused by mutations in the dystrophin gene. The dystrophin gene is located on the X chromosome, and, therefore, disease-causing mutations in dystrophin occur most often in males. Therefore, females with dystrophin deficiency or other forms of muscular dystrophy may be undiagnosed or misdiagnosed. Immunohisto-chemistry was used to analyze dystrophin and a number of other muscle proteins associated with muscular dystrophy in humans, including sarcoglycans and laminin ,2, in muscle biopsy specimens from 5 female dogs with pathologic changes consistent with muscular dystrophy. The female dogs were presented with a variety of clinical signs including generalized weakness, muscle wasting, tremors, exercise intolerance, gait abnormalities, and limb deformity. Serum creatine kinase activity was variably high. One dog had no detectable dystrophin in the muscle; another was mosaic, with some fibers normal and others partly dystrophin-deficient. A 3rd dog had normal dystrophin but no detectable laminin ,2. Two dogs could not be classified. This study demonstrates the occurrence of dystrophin- and laminin ,2-associated muscular dystrophy and the difficulty in clinical diagnosis of these disorders in female dogs. [source] Breakdown of adenine nucleotide pool in fatiguing skeletal muscle in McArdle's disease: A noninvasive 31P-MRS and EMG studyMUSCLE AND NERVE, Issue 6 2003Jochen Zange PhD Abstract Energy metabolism and electrical muscle activity were studied in the calf muscles of 19 patients with proven McArdle's disease and in 25 healthy subjects. Phosphorus magnetic resonance spectroscopy and surface electromyography (S-EMG) were performed during two isometric muscle contractions of 3 min at 30% maximum voluntary contraction, one performed during normal perfusion and the other during applied ischemia. After about 1 min of ischemic muscle contraction in diseased muscle a significant acceleration in phosphocreatine breakdown was observed, along with a significant decrease in adenosine triphosphate. During both contractions the absence of glycolysis was shown by a significant alkalinization. Furthermore, in patients we observed a greater increase in the S-EMG amplitude than in control subjects. We conclude that early on during moderate exercise, a small number of muscle fibers reach metabolic depletion, indicated by a reduction in the adenine nucleotide pool. An increasing number of motor units, which are still in a high-energy state, are continuously recruited to compensate for muscle fatigue. This functional compartmentation may contribute to the pathophysiology of exercise intolerance in McArdle's disease. Muscle Nerve 27: 728,736, 2003 [source] Effects of sildenafil on pulmonary hypertension and exercise tolerance in severe cystic fibrosis-related lung disease,PEDIATRIC PULMONOLOGY, Issue 4 2006Gregory S. Montgomery MD Abstract Cystic fibrosis (CF) patients with advanced lung disease are at risk for developing pulmonary vascular disease and pulmonary hypertension, characterized by progressive exercise intolerance beyond the exercise-limiting effects of airways disease in CF. We report on a patient with severe CF lung disease who experienced clinically significant improvements in exercise tolerance and pulmonary hypertension without changing lung function during sildenafil therapy. Pediatr Pulmonol. © 2006 Wiley-Liss, Inc. [source] Cystic fibrosis transmembrane conductance regulator in human muscle: Dysfunction causes abnormal metabolic recovery in exerciseANNALS OF NEUROLOGY, Issue 6 2010Anne-Marie Lamhonwah PhD Objective Individuals with cystic fibrosis (CF) have exercise intolerance and skeletal muscle weakness not solely attributable to physical inactivity or pulmonary function abnormalities. CF transmembrane conductance regulator (CFTR) has been demonstrated in human bronchial smooth and cardiac muscle. Using 31P-magnetic resonance spectroscopy of skeletal muscle, we showed CF patients to have lower resting muscle adenosine triphosphate and delayed phosphocreatine recovery times after high-intensity exercise, suggesting abnormal muscle aerobic metabolism; and higher end-exercise pH values, suggesting altered bicarbonate transport. Our objective was to study CFTR expression in human skeletal muscle. Methods and Results We studied CFTR expression in human skeletal muscle by Western blot with anti-CFTR antibody (Ab) L12B4 and demonstrated a single band with expected molecular weight of 168kDa. We isolated the cDNA by reverse transcription polymerase chain reaction and directly sequenced a 975bp segment (c. 3,600,4,575) that was identical to the human CFTR sequence. We showed punctate staining of CFTR in sarcoplasm and sarcolemma by immunofluorescence microscopy with L12B4 Ab and secondary Alexa 488-labeled Ab. We confirmed CFTR expression in the sarcotubular network and sarcolemma by electron microscopy, using immunogold-labeled anti-CFTR Ab. We observed activation of CFTR Cl, channels with iodide efflux, on addition of forskolin, 3-isobutyl-1-methyl-xanthine, and 8-chlorphenylthio,cyclic adenosine monophosphate, in wild-type C57BL/6J isolated muscle fibers in contrast to no efflux from mutant F508del-CFTR muscle. Interpretation We speculate that a defect in sarcoplasmic reticulum CFTR Cl, channels could alter the electrochemical gradient, causing dysregulation of Ca2+ homeostasis, for example, ryanodine receptor or sarco(endo)plasmic reticulum Ca2+ adenosine triphosphatases essential to excitation-contraction coupling leading to exercise intolerance and muscle weakness in CF. ANN NEUROL 2010 [source] ,-enolase deficiency, a new metabolic myopathy of distal glycolysisANNALS OF NEUROLOGY, Issue 2 2001Giacomo P. Comi MD A severe muscle enolase deficiency, with 5% of residual activity, was detected in a 47-year-old man affected with exercise intolerance and myalgias. No rise of serum lactate was observed with the ischemic forearm exercise. Ultrastructural analysis showed focal sarcoplasmic accumulation of glycogen , particles. The enzyme enolase catalyzes the interconversion of 2-phosphoglycerate and phosphoenolpyruvate. In adult human muscle, over 90% of enolase activity is accounted for by the ,-enolase subunit, the protein product of the ENO3 gene. The ,-enolase protein was dramatically reduced in the muscle of our patient, by both immunohistochemistry and immunoblotting, while ,-enolase was normally represented. The ENO3 gene of our patient carries two heterozygous missense mutations affecting highly conserved amino acid residues: a G467A transition changing a glycine residue at position 156 to aspartate, in close proximity to the catalytic site, and a G1121A transition changing a glycine to glutamate at position 374. These mutations were probably inherited as autosomal recessive traits since the mother was heterozygous for the G467A and a sister was heterozygous for the G1121A transition. Our data suggest that ENO3 mutations result in decreased stability of mutant ,-enolase. Muscle ,-enolase deficiency should be considered in the differential diagnosis of metabolic myopathies due to inherited defects of distal glycolysis. [source] The Difference of Heart Rate Recovery between Males with and without Erectile DysfunctionANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2010M. Tolga Dogru M.D. Aim: In this study, we aimed to investigate the relationship between heart rate recovery (HRR) time and Chronotropic Index (CHIND) parameters, which also reflect autonomic function, after exercise stress test (EST) in males with or without erectile dysfunction (ED), and we investigated the relationship between HRR and CHIND and serum steroid hormone levels. Material and Methods: A total of 135 participants (mean age: 45.0 ± 11.8 years) were enrolled into the study. Detailed biochemical and hormonal analyses, 12-lead electrocardiography and EST (Treadmill) were performed in all participants. Erectile function was assessed using the International Index of Erectile Function (IIEF) questionnaire form. Patients were categorized into two groups according to their IIEF scores as ED (+) (IIEF < 26) and ED (,) (IIEF , 26). Afterward, statistical analyses were performed to evaluate the correlations between ED and HRR and CHIND. Results: A total of 65 patients were ED (+) (mean age 44.9 ± 6.4 years), while 70 patients (mean age 43.7 ± 7.7 years) had normal erectile status. There were statistically significant differences in CHIND (P = 0.015) and HRR time (P = 0.037) between ED (+) and ED (,) patients. In correlation analysis, IIEF score was found positively correlated with HRR and metabolic equivalent (MET) values (rHRR= 0.293, P = 0.037; rMETs= 0.388, P = 0.011, respectively). Linear regression analysis revealed that METs value and total exercise time had a more linear relationship with IIEF score compared to the other EST parameters (pMETs= 0.002 and pTET= 0.015, respectively). Conclusion: Chronotropic incompetence and dynamic postexercise autonomic dysfunction are present in ED patients. This condition may reflect decreased functional capacity and exercise intolerance in these patients. Ann Noninvasive Electrocardiol 2010;15(3):223,229 [source] Complete heart block associated with lupus in a dogAUSTRALIAN VETERINARY JOURNAL, Issue 7 2003R MALIK A 5-year-old Poodle-cross was initially presented for exercise intolerance and difficulty in chewing and yawning. Some months later it acutely developed lethargy referable to complete heart block. Further investigations before and after permanent pacemaker implantation demonstrated Coombs-positive immune-mediated haemolytic anaemia, presumptive masticatory myositis and hypoadrenocorticism, suggesting the possibility of multisystem auto-immune disease. A diagnosis of systemic lupus erythematosus (SLE) was made based on these findings and a positive anti-nuclear antibody titre. It was thought that immune-mediated destruction of cardiac conduction tissues was responsible for the development of atrioventricular conduction block. Glucocorticoid deficiency was corrected using cortisone replacement therapy. SLE was controlled successfully for 10 months using azathio-prine monotherapy until signs, subsequently shown to be due to subacute bacterial endocarditis, resulted in the death of the patient. Lupus should be considered as a potential underlying aetiology in dogs that develop heart block. [source] Airway limitation and exercise intolerance in well-regulated myasthenia gravis patientsACTA NEUROLOGICA SCANDINAVICA, Issue 2010A. Elsais Elsais A, Johansen B, Kerty E. Airway limitation and exercise intolerance in well-regulated myasthenia gravis patients. Acta Neurol Scand: 2010: 122 (Suppl. 190): 12,17. © 2010 John Wiley & Sons A/S. Objectives,,, Myasthenia gravis (MG) is an autoimmune disease of neuromuscular synapses, characterized by muscular weakness and reduced endurance. Remission can be obtained in many patients. However, some of these patients complain of fatigue. The aim of this study was to assess exercise capacity and lung function in well-regulated MG patients. Patients and methods,,, Ten otherwise healthy MG patients and 10 matched controls underwent dynamic spirometry, and a ramped symptom-limited bicycle exercise test. Spirometric variables included forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), and maximum voluntary ventilation (MVV). Exercise variables included maximal oxygen uptake (VO2 max), anaerobic threshold (VO2 AT) maximum work load (W), maximum ventilation (VE max), and limiting symptom. Results,,, Myasthenia gravis patients had significantly lower FEV1/FVC ratio than controls. This was more marked in patients on acetylcholine esterase inhibitors. On the contrary, patients not using acetylcholine esterase inhibitors had a significantly lower exercise endurance time. Conclusion,,, Well-regulated MG patients, especially those using pyridostigmine, tend to have an airway obstruction. The modest airway limitation might be a contributing factor to their fatigue. Patients who are not using acetylcholinesterase inhibitor seem to have diminished exercise endurance in spite of their clinically complete remission. [source] Altered cardiovascular vagal responses in nonelderly female patients with subclinical hyperthyroidism and no apparent cardiovascular diseaseCLINICAL ENDOCRINOLOGY, Issue 2 2007Renata Boschi Portella Summary Objective Subclinical hyperthyroidism (SH) has been associated with exercise intolerance, changes in cardiac morphology, atrial arrhythmias and sympathovagal imbalance. The aim of this study was to evaluate the vagal reserve and modulation by a sympathetic stimulus in nonelderly patients with SH without cardiovascular problems. Design We carried out a cross-sectional study, comparing data of the heart rate variability (HRV) of SH patients and healthy controls at rest and after vagal and sympathetic stimulation. Patients We studied 16 female patients with at least 6 months of SH and 16 healthy female controls with the same median age (40 vs. 34·5 years). Measurements We used the tilt test, with electrocardiographic record at rest, during the respiratory sinus arrhythmia (RSA) manoeuvre and after tilting, in order to analyse HRV in the frequency domain (%high frequency (HF) and low/high frequency ratio (LF/HF) using Biopotentials Captation System software. Results The median TSH level was 0·03 mU/l in patients and 1·37 mUI/l in controls. The median free T4 was 1·37 ng/dl in patients and 1·20 ng/dl in controls. Patients demonstrated a significantly smaller difference between %HF during the RSA and %HF at rest than controls (median ,7·5 vs. 36·6, P < 0·001). There was a lower difference between LF/HF ratio after tilting and LF/HF ratio at rest in patients than in controls (1·5 vs. 5·3, P = 0·005). Conclusion Subclinical hyperthyroidism affects cardiovascular autonomic balance in otherwise apparently healthy nonelderly females by blunting vagal responses. [source] Prefrontal cortex oxygenation during incremental exercise in chronic fatigue syndromeCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 6 2008J. Patrick Neary Summary This study examined the effects of maximal incremental exercise on cerebral oxygenation in chronic fatigue syndrome (CFS) subjects. Furthermore, we tested the hypothesis that CFS subjects have a reduced oxygen delivery to the brain during exercise. Six female CFS and eight control (CON) subjects (similar in height, weight, body mass index and physical activity level) performed an incremental cycle ergometer test to exhaustion, while changes in cerebral oxy-haemoglobin (HbO2), deoxy-haemoglobin (HHb), total blood volume (tHb = HbO2 + HHb) and O2 saturation [tissue oxygenation index (TOI), %)] was monitored in the left prefrontal lobe using a near-infrared spectrophotometer. Heart rate (HR) and rating of perceived exertion (RPE) were recorded at each workload throughout the test. Predicted VO2peak in CFS (1331 ± 377 ml) subjects was significantly (P , 0·05) lower than the CON group (1990 ± 332 ml), and CFS subjects achieved volitional exhaustion significantly faster (CFS: 351 ± 224 s; CON: 715 ± 176 s) at a lower power output (CFS: 100 ± 39 W; CON: 163 ± 34 W). CFS subjects also exhibited a significantly lower maximum HR (CFS: 154 ± 13 bpm; CON: 186 ± 11 bpm) and consistently reported a higher RPE at the same absolute workload when compared with CON subjects. Prefrontal cortex HbO2, HHb and tHb were significantly lower at maximal exercise in CFS versus CON, as was TOI during exercise and recovery. The CFS subjects exhibited significant exercise intolerance and reduced prefrontal oxygenation and tHb response when compared with CON subjects. These data suggest that the altered cerebral oxygenation and blood volume may contribute to the reduced exercise load in CFS, and supports the contention that CFS, in part, is mediated centrally. [source] Fabry Disease: Treatment and diagnosisIUBMB LIFE, Issue 11 2009Paula A. Rozenfeld Abstract Fabry disease is an X-linked lysosomal disorder that results from a deficiency of the lysosomal enzyme ,-galactosidase A leading to accumulation of glycolipids, mainly globotriaosylceramide in the cells from different tissues. Classical Fabry disease affects various organs. Clinical manifestations start at early age and include angiokeratoma, acroparesthesia, hypohydrosis, heat/exercise intolerance, gastrointestinal pain, diarrhea, and fever. The main complications of Fabry disease are more prominent after the age of 30 when kidney, heart, and/or cerebrovascular disorders appear. Most of the heterozygous females are symptomatic. Enzyme replacement therapy (ERT) is the only specific treatment for Fabry disease. The beneficial effect of ERT on different organs/systems has been extensively evaluated. Quality of life of patients receiving ERT is improved. Enzyme replacement stabilizes or slows the decline in renal function and reduces left ventricular hypertrophy. Fabry disease may be underdiagnosed because of nonspecific and multiorgan symptoms. Different screening strategies have been carried out in different at-risk populations in order to detect undiagnosed Fabry patients. An increasing knowledge about Fabry disease within the medical community increases the chances of patients to receive a timely diagnosis and, consequently, to access the appropriate therapy. © 2009 IUBMB IUBMB Life, 61(11): 1043,1050, 2009 [source] | |||||||||||||||||||||||||