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At least 1,657 records · Page 92Linked to original sources
PubMed2001

Aerosolized iloprost in CREST syndrome related pulmonary hypertension.

OBJECTIVE: To assess the outcome of patients with CREST syndrome associated severe pulmonary hypertension treated by aerosolized iloprost in a noncomparative study. METHODS: Five patients with CREST syndrome associated severe pulmonary hypertension were treated with 100 microg/day of aerosolized iloprost. New York Heart Association functional class and exercise tolerance (6 min walk test) were assessed at baseline, after one month, and then every 6 months. A right heart catheterization was performed at baseline in all but one patient. Systolic pulmonary artery pressure (PAP) was measured with Doppler echocardiography after one month and every 6 months. RESULTS: The mean followup was 13.2 +/- 8.8 months (median 6, range 6-24). Subjective quality of life improved in all patients. NYHA functional class decreased from Class III to II in 3 patients, from Class III to I in one patient, and from Class IV to III in one patient. At 6 months, the distance walked in 6 min had increased from 352 +/- 48 to 437 +/- 56 m (p = 0.06). At one month the mean systolic PAP was 58 +/- 13 vs 81 +/- 9 mm Hg at baseline (p = 0.04). At 6 months the mean systolic PAP was 57 +/- 13 mm Hg (p = 0.06). The improvement of both clinical and hemodynamic status was maintained in the 2 patients treated for 2 years. Neither adverse effects nor need to increase the daily dose of iloprost were observed. One patient died of right heart failure and one patient did not experience any improvement of exercise tolerance and hemodynamics. CONCLUSION: Aerosolized iloprost might be potentially useful as treatment for CREST syndrome associated pulmonary hypertension. However, patients who could benefit from this treatment will probably have to undergo careful criteria selection.

Administration, Inhalation↗
PubMed2005

[Carvedilol in combined therapy of patients with Q myocardial infarction].

AIM: To evaluate effects of carvedilol (Akridilol, AKRIKHIN, Russia) on central hemodynamics, microvascular bed, hemorheology, von Willebrand factor (VWF) activity, clinical efficacy of the drug and influence on exercise tolerance in patients with Q myocardial infarction (QMI) compared to therapy with atenolol. MATERIAL AND METHODS: The trial covered 90 patients with acute QMI. All the patients had cardiac failure and were divided into 3 comparable groups. Group 1 received carvedilol in a dose 6.25-50 mg/ day. Group 2 received atenolol in a dose 12.5-50 mg/day. Group 3 had contraindications to therapy with beta-adrenoblockers. The patients were followed up for 60 +/- 2 days. The following methods were employed in the study: clinical examination, echocardiography, laser Doppler flowmetry (LDF), Holter ECG monitoring, examination of platelet-vessel hemostasis, VWF activity, treadmill-test, statistical processing with the program Excel 7.0. RESULTS: Inclusion of beta-adrenoblockers in combined therapy of QMI patients with cardiac failure considerably improves treatment efficacy. These drugs, carvedilol in particular, inhibit postinfarctional remodeling and thus development and progress of cardiac failure. Carvedilol reduces stasis in the microcirculatory bed, corrects abnormal response of microhemodynamics to sympathic activation and operation of venuloarteriolar mechanisms of capillary blood flow regulation. High clinical efficacy of the combined therapy of QMI patients is explained by marked antianginal and antiischemic effects of carvedilol. Treadmill test showed that the addition of beta-adrenoblockers to therapy raised exercise tolerance in the postinfarctional period.

Adrenergic beta-Antagonists↗
PubMed2006

[The vegetative status of patients after myocardial infarction, and the effectiveness of sanatorium rehabilitation].

The aim of the study was to investigate the dynamics of functional variables and the vegetative status of patients undergoing sanatorium rehabilitation with different results. The subjects, 106 patients aged 48.6 +/- 0.95, who had had myocardial infarction, were divided into 3 groups according to the dynamics of physical exercise tolerance (PET) in the course of treatment: group I, 39 patients with a significant (more than 10W) increase in PET; group II, 47 patients with no change in PET or with a small (up to 10W) increase in PET; group 3, 20 patients with a decrease in PET. An initial examination showed PET was the lowest in group 1. Group 3 patients displayed the lowest ejection fraction, the biggest end-diastolic volume and left ventricular (LV) asynergy at an initial examination, as well as higher incidence of ventricular premature beats; this group contained more patients with large-focal MI, LV aneurism, and postinfarction stenocardia. After treatment group 1 patients demonstrated an increase in the low-frequency component of the spectral parameters of cardiac rhythm variability (CRV) according to ECG at rest; active orthostatic test (AOT) revealed a moderate increase in the variables of sympathovagal balance, which could be considered to demonstrate the recovery of the impaired sympathetic reactivity. Group III patients demonstrated a decrease in the low-frequency component of the CRV spectral parameters at rest after treatment; AOT demonstrated a shift from an initial inadequate sympathetic reactivity to hyperreactivity, which might reflect a "stale" condition in these patients. The data of the study will help to plan individual physical rehabilitation programs and to control exercise tolerance in cardiological patients.

Autonomic Nervous System Diseases↗
PubMed2005

Genomic and non-genomic regulation of L-type calcium channels in rat ventricle by thyroid hormone.

Hyperthyroidism is associated with low exercise tolerance despite high cardiac output and sometimes with the development of heart failure. L-type calcium channels may play a role in the mechanism, but this has not been fully understood. We examined the effects of thyroid hormone on gene expression and function of L-type calcium channels in rat ventricles by the ribonuclease protection assay and whole-cell patch-clamp technique, respectively. The effects of bisoprolol, beta-blocking agent, on the regulation of calcium channel by thyroid hormone was also studied. In hyperthyroid animals, the mRNA of the calcium channel alpha1c subunit was reduced on day 4, compared with that in euthyroid animals, and remained low on day 8. Bisoprolol did not affect the thyroid hormone mediated decrease in alpha1c subunit mRNA. While L-type calcium current was greater in hyperthyroid than euthyroid myocytes on day 4, it was smaller on day 8. In addition, the isoproterenol-induced increase in calcium current in euthyroid rats was attenuated in hyperthyroid rats. Acetylcholine decreased calcium current in hyperthyroid myocytes, but not in euthyroid myocytes. In conclusion, L-type calcium current was increased by thyroid hormone in rat ventricular myocytes by the activation of the adenylate cyclase cascade, despite a decreased calcium channel gene expression. These genomic and non-genomic modifications may play an important role in the association of high cardiac output with low exercise tolerance, and in the development of heart failure in hyperthyroidism.

Acetylcholine↗
PubMed2001

Differential lipogenic effects of cilostazol and pentoxifylline in patients with intermittent claudication: potential role for interleukin-6.

Cilostazol, a novel oral phosphodiesterase inhibitor, has shown consistent improvement in exercise tolerance in patients with intermittent claudication (IC). In addition to this effect, cilostazol has previously been shown to have beneficial effects on the dyslipidemia, i.e., combination of high triglycerides with low high-density-lipoprotein cholesterol (HDL-C) levels. Interleukin-6 (IL-6) suppresses the activity of lipoprotein lipase, which modulates the metabolism of triglycerides and HDL-C. To determine whether a reduction of IL-6 contributes to the improvement of lipid profiles, we prospectively investigated the effect of cilostazol (n=16, 100 mg, twice daily) on the changes of lipid profiles and on the association with the changes of IL-6 compared with those of pentoxifylline (n=16, 400 mg, bid) in patients with IC. After eight weeks of administration of cilostazol to patients with IC, walking distances were increased, associated with a 29% decrease in plasma triglycerides and a 13% increase in HDL-C. No significant changes of lipid profiles in the pentoxifylline and placebo groups were observed although a similar improvement in walking distances was achieved in the pentoxifylline group. IL-6 levels were significantly reduced in patients receiving cilostazol as compared with those receiving placebo or pentoxifylline. The cilostazol-induced changes in the IL-6 were positively related to those of triglycerides in the cilostazol group (r=0.63, P<0.05) and negatively related to those of HDL-C (r=-0.55, P<0.05). These findings suggest that in addition to consistent improvement of exercise tolerance, cilostazol may improve lipid profiles by reducing IL-6 release. However, pentoxifylline did not affect lipid profiles although a similar improvement of maximal walking distance (MWD) was achieved.

Aged↗
PubMed2003

New concepts in the treatment of ankle joint fractures. The IP-XS (XSL) and IP-XXS (XXSL) nail in the treatment of ankle joint fractures.

INTRODUCTION: The most important factor in the treatment of ankle joint fractures is stable anatomical reconstruction of the syndesmosis and joint surface. In the course of this, attention must be paid to soft-tissue damage with the risk of deep infections. Early functional therapy and exercise tolerance must be called for. The choice of surgical access route, in particular in the case of critical arterial circulation, and the possible irritation of the soft tissue by the osteosynthesis material prompted us to seek alternative osteosynthesis techniques. MATERIAL AND METHODS: Following a preclinical study and very good initial results with the XS nail in the treatment of patella and olecranon fractures, this was now also used for ankle joint fractures at the medial malleolus and lateral malleolus. In the period from 5/2000 to 1/2002, 194 ankle joint fractures were treated using the XS nail. These were predominantly Weber B, C and bimalleolar fractures. In the case of ankle joint fractures, osteosynthesis was carried out following precise open fracture repositioning. In the case of isolated fibula fractures, early loading was allowed within 1 week; in the case of bimalleolar fractures, there was immediate partial loading with 20 kg for 4 weeks, after which they were subjected to full loading. Where there was an additional Volkmann fracture, we allowed only immediate partial loading with 10 kg for 6 weeks. All 194 patients were observed prospectively, and 162 (83.5%) could be followed up after 15 months. The results were classified according to the scale described by Olerud. RESULTS: It has been possible to follow up 162 patients, with an average age of 49.7 years. There were 62 (38.3%) Weber B and 45 (27.8%) Weber C fractures. In 55 (34.0%) cases, bimalleolar fractures were present. According to the Olerud score, 95 (58.6%) of the patients had an excellent outcome, 54 (33.3%) a good one, 9 (5.5%) a fair one and 4 (2.5%) an unsatisfactory outcome. In 3 cases a threaded wire dislocation occurred, without complications. Two mesh graft transplants were necessary; otherwise, there were no soft-tissue problems requiring review. One pseudarthrosis was seen. CONCLUSION: The XS nail which is introduced here fulfils the requirements made of an implant as regards maximum protection of soft tissue, secure fracture fixation and early exercise tolerance, including ankle fractures. No implant dislocation, no deep infection and no re-osteosynthesis were observed. Its advantages over conventional techniques lie precisely in the treatment of complex fractures and for patients with poor bone, vascular and soft-tissue situations.

Adolescent↗
PubMedDate not supplied

Do the kinetics of peripheral muscle oxygenation reflect systemic oxygen intake?

To examine whether the kinetics of local muscle oxygenation reflect systemic oxygen intake, we measured the kinetics of local muscle oxygenation and systemic oxygen consumption (VO2). This study included 16 healthy males who performed an exercise tolerance test on a bicycle ergometer. During the exercise test, expiratory gas analysis was performed with an expiratory gas analyzer, and the kinetics of vastus lateralis muscle oxygenation were determined by near-infrared spectroscopy (NIRS). Oxygenated hemoglobin (OxyHb) and tissue blood oxygen saturation (StO2) gradually decreased during the exercise test, while deoxygenated hemoglobin (DeoxyHb) gradually increased. We examined correlations between the mean values of these parameters, which were calculated by time-integrating the values obtained using NIRS and dividing them by the integral time, and VO2. There was a marked positive correlation between DeoxyHb and VO2 (r = 0.893-0.986), and a marked negative correlation between StO2 and VO2 (r = 0.859-0.995). There was a negative correlation between VO2 and OxyHb (r = 0.726-0.978), and no correlation between TotalHb and VO2. These results suggest that the kinetics of peripheral muscle oxygenation reflect systemic VO2.

Adult↗
PubMed1982

Exercise assessment of sinoatrial node function following the Mustard operation.

To screen for sinoatrial node dysfunction following the Mustard procedure for transposition of the great arteries, we studied the chronotropic response to graded maximal treadmill exercise in 29 patients at mean 6.7 years after operation. Although 93% of patients had normal resting heart rate (HR), 83% demonstrated significant depression of maximum HR and/or recovery HR after termination of exercise. These findings were similarly present among a subset of 13 patients with normal exercise tolerance. Resting and exercise-induced HR in 10 patients receiving chronic digoxin therapy were no different than in the 19 patients without medication. Sixteen patients with abnormal chronotropic responses to exercise had intracardiac electrophysiologic evaluation which confirmed sinoatrial node dysfunction in nine. Abnormal HR responses did not correlate with clinical symptoms, cardiac arrhythmias, or postoperative hemodynamics. Maximal exercise testing may be a sensitive noninvasive method to identify sinoatrial node dysfunction in postoperative children.

Adolescent↗
PubMed1985

Lack of efficacy of nafazatrom, a novel anti-thrombotic compound, in patients with coronary artery disease.

Nafazatrom (Bay G 6575) is a novel antithrombotic compound, which acts by stimulation of prostacyclin as well as by inhibition of lipoxygenase enzymes. To determine its effects on exercise performance in coronary artery disease patients, a double-blind study was conducted. Twenty patients with coronary artery disease underwent an exercise stress test before and 2 hours after administration of placebo or nafazatrom (1.2 gm). Before the drug administration, there was evidence of enhanced platelet activity, as reflected by elevated resting plasma beta thromboglobulin and thromboxane B2 concentrations. Plasma 6-keto-PGF1 alpha levels were undetectable in most patients. All coagulation tests were in the normal range. None of these parameters changed with exercise. Administration of placebo or nafazatrom before the exercise stress test did not significantly influence any of the coagulation or platelet function parameters or plasma concentrations of thromboxane B2 and 6-keto-PGF1 alpha. This lack of effect was evident both at rest and upon exercise. Compared to placebo, nafazatrom did not significantly increase exercise tolerance time or exercise-induced symptoms. In conclusion, nafazatrom did not influence exercise performance in patients with coronary disease.

6-Ketoprostaglandin F1 alpha↗
PubMed1988

Postural exercise abnormalities in symptomatic patients with mitral valve prolapse.

The hemodynamics of the supine and upright exercise response in 16 symptomatic women with mitral valve prolapse (Group I) was compared with that in 8 asymptomatic normal control women (Group II). All subjects had supine and upright echocardiography and phonocardiography at rest and none demonstrated mitral regurgitation. All participants then underwent same day graded bicycle exercise, with simultaneous radionuclide angiography in both the upright and the supine posture. Catecholamines were measured, and a variety of volumetric and hemodynamic data were obtained. Group I (patients with mitral valve prolapse) demonstrated a reduced exercise tolerance, especially during upright exercise, as measured by both total exercise duration and maximal work load achieved. Mean total catecholamine measurements were similar between the two study groups at comparable mean heart rate, mean blood pressure and mean rate-pressure (double) product. No difference was observed in the ratio of right to left ventricular stroke counts at rest or during exercise regardless of posture, suggesting that exercise-induced mitral regurgitation did not occur. A difference was noted, however, in left ventricular end-diastolic volume index. At rest, Group I patients exhibited a 42% decrease in this index when sitting upright, and this difference from supine values persisted at submaximal (300 kpm/min) and peak work loads (34 and 29% difference, respectively). This contrasted with the control subjects whose upright end-diastolic volumes at rest, at 300 kpm/min and at peak exercise were reduced 21, 10 and 3%, respectively, compared with supine values. Cardiac index measurements reflected the reduced left ventricular end-diastolic volume observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2004

Effect of exercise mode on oxygen uptake and blood gases in COPD patients.

Patients with chronic obstructive pulmonary disease (COPD) are characterised by decreased exercise tolerance, and, more variably, exercise induced hypoxaemia (EIH). Evaluation of physical work capacity and physiological responses to exercise may be performed by various procedures, but there are diverging opinions as to which exercise test should be preferred. In the current study, oxygen uptake and arterial blood gases in COPD patients have been compared during submaximal and maximal exercise on treadmill and ergometer bicycle. Treadmill exercise resulted in higher peak oxygen uptake than bicycle exercise (1111+/-235 vs. 987+/-167 ml min(-1), P<0.02), while the plasma lactate levels were higher during cycling (1.8+/-0.8 vs. 3.8+/-1.7 mmol l(-1), P<0.001). Neither carbon dioxide output, ventilation, nor rate of perceived exertion (Borg RPE scale) showed significant differences between the two modes of exercise. The EIH during both maximal (delta Sa,O2 = -5.6+/-4.2 vs. -3.4+/-5.1%) and sub-maximal exercise was more pronounced during treadmill walking than during cycling. The present study indicates that the VO2peak in COPD patients is higher, the maximal lactate concentrations lower and the development of EIH more pronounced when exercise testing is performed on a treadmill than on a bicycle ergometer.

Adult↗
PubMed1990

Benefits and risks of anemia correction with recombinant human erythropoietin in children maintained by hemodialysis.

Ten children with renal failure (age range 2 years 6 months to 18 years 9 months; median 11 years 10 months), maintained by long-term hemodialysis, had successful correction of their anemia after intravenous administration of recombinant human erythropoietin in a dosage escalating every 2 weeks (75 to 150 to 300 to 450 IU/kg/wk). Mean hemoglobin concentration increased from 6.4 +/- 0.9 to 11.5 +/- 1.0 gm/dl. Blood cell counts used to evaluate the correction of anemia were done after dialysis; this was especially important for children less compliant with water restriction. The higher hemoglobin concentration resulted in improvement of the quality of life, a greater tolerance for physical effort (exercise tolerance doubled and the ventilatory anaerobic threshold increased significantly), correction of some subclinical central nervous system abnormalities detected by evoked potentials testing, and reduction of bleeding time. Few side effects were noted; severe hypertension developed in one patient when postdialysis hematocrit was only 28%, and there were two episodes of hypertransaminasemia with no other evidence of liver dysfunction. We conclude that in children with renal failure the use of recombinant human erythropoietin to correct anemia is safe and strongly advisable, because of the resolution of many of the symptoms correlated with anemia.

Adolescent↗
PubMed1999

Left ventricular ischemia due to coronary stenosis as an unexpected treatable cause of paroxysmal atrial fibrillation.

We present a patient with exercise-induced paroxysmal atrial fibrillation who was eventually scheduled for a Cox-maze operation due to persistence of his complaints of fatigue, impaired exercise tolerance, and predominantly exercise-related irregular palpitations despite treatment with several antiarrhythmic drugs. A preoperative exercise stress test without antiarrhythmic or negative chronotropic drugs, however, showed clear evidence of myocardial ischemia. After coronary angioplasty of a significant stenosis in the left anterior descending artery, there was no recurrence of atrial fibrillation during a follow-up of 7 months.

Adult↗
PubMed2006

Calcified occlusion of the right coronary artery in Kawasaki disease: evidence of myocardial ischaemia using cardiac technetium-99m-tetrofosmin perfusion single-photon emission computed tomography.

We report the case of a 14-year-old boy who developed Kawasaki disease at 5 months of age. The patient developed severe aneurysmal disease of both the left and right coronary arteries. He eventually developed total calcified occlusion of the right coronary artery despite long-term treatment with aspirin. Catheterisation showed no antegrade flow into the right coronary artery, with retrograde flow from the left coronary system into the right coronary. At the most recent follow-up he was asymptomatic, with normal exercise tolerance and a negative exercise stress test. Single-photon emission computed tomography (SPECT) myocardial perfusion imaging was carried out during stress and at rest using intravenous persantine (dipyridamole) and technetium-99m tetrofosmin. During stress, there were prominent left ventricular apical and anteroseptal defects, which normalised at rest. SPECT during stress and at rest may detect subclinical ischaemia and influence further management options in such patients.

Adolescent↗
PubMed2006

Skeletal muscle dysfunction in chronic renal failure: effects of exercise.

A number of chronic illnesses such as renal failure (CRF), obstructive pulmonary disease, and congestive heart failure result in a significant decrease in exercise tolerance. There is an increasing awareness that prescribed exercise, designed to restore some level of physical performance and quality of life, can be beneficial in these conditions. In CRF patients, muscle function can be affected by a number of direct and indirect mechanisms caused by renal disease as well as various treatment modalities. The aims of this review are twofold: first, to briefly discuss the mechanisms by which CRF negatively impacts skeletal muscle and, therefore, exercise capacity, and, second, to discuss the available data on the effects of programmed exercise on muscle function, exercise capacity, and various other parameters in CRF.

Exercise Therapy↗