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PubMedDate not supplied

[Therapeutic effectiveness of molsidomine in patients with exercise-induced angina pectoris].

Exercise tolerance was tested with cycloergometer, and ECG recorded in 33 patients with exercise-induced angina pectoris. Patients' age ranged from 36 to 65 years. Tests were performed prior to and after a single oral dose 2 mg of molsidomine or placebo. Molsidomine reduced the number of patients with exercise-induced coronary pain from 33 to 25, i.e. from 84.5% to 27.27%. Pain-free period was significantly longer in patients given molsidomine whereas postexercise pain and total duration of the coronary pain were significantly shorter. Total work was markedly higher, and maximum ST depression in ECG record following exercise was significantly lower than the values noted prior to molsidomine administration and in placebo group. Heart rates both resting and during exercise did not differ in molsidomine and placebo groups. Molsidomine may be considered as an effective drug preventing exercise-induced anginal pain within 1 hour after administration.

Adult↗

PubMed1990

Exaggerated pressure response to exercise in men at risk for systemic hypertension.

Normotensive persons at high risk of developing systemic hypertension have greater cardiovascular reactivity to mental and physical stressors. This study compared cardiovascular responses to exercise in normotensive men (aged 28 +/- 0.8 years [mean +/- standard error of the mean]) at high risk (positive parental history and high normal resting blood pressure [BP], n = 20) and at low risk (negative history, low normal BP, n = 15) of hypertension. All men had normal body weight and exercise tolerance. During graded supine bicycle exercise, 35% (7 of 20) of high-risk men had exaggerated BP responses (greater than or equal to 230/100 mm Hg) versus 0% of low-risk men, thus forming 3 groups (low risk, high-risk normal BP response, high-risk exaggerated response). Cardiac function was measured by nuclear cardiography. Cardiac index, peripheral resistance index, left ventricular ejection fraction and contractility index were measured at rest and during each exercise work load. High-risk exaggerated responders could not be distinguished from their high-risk normal-responding counterparts using resting BP or other cardiovascular variables. During exercise all 3 groups had equivalent increases in cardiac output. However, the high-risk exaggerated responders had blunting in peripheral resistance decline, resulting in excessive BP increases. This finding suggests an impaired capacity for exercise-induced vasodilation, indicating that the exaggerated response group may be at highest risk for future hypertension in these 3 groups.

Adult↗

PubMed1989

Cardiac refractoriness. Age-dependence in normal subjects.

The effects of age on cardiac electrophysiologic measurements were assessed in 30 subjects between the ages of 18 and 73 years and free of structural heart disease. Occult heart disease was excluded by a normal treadmill exercise tolerance test, a rest and exercise radionuclide angiogram, and/or a cardiac catheterization. Effective and functional refractory periods of right atrium, right ventricle, and atrioventricular node were assessed. The relationship between these measurements and age was examined using linear regression. There were significant correlations between age and atrial effective and functional refractory periods, atrioventricular effective refractory period, and ventricular effective and functional refractory periods. Other electrophysiologic measures showed no such relationship with age.

Adult↗

PubMedDate not supplied

Hypertrophic cardiomyopathy--therapy with slow channel inhibiting agents.

Slow channel inhibiting agents, particularly verapamil, appear to produce beneficial effects in relieving symptoms of dyspnea, chest pain, and syncope or presyncope in over 70% of patients with hypertrophic cardiomyopathy. Symptomatic relief occurs in patients with and without left ventricular outflow obstruction. Exercise hemodynamics, exercise tolerance, and cardiac performance during exercise tend to improve. The mechanisms for this symptomatic improvement, however, are not fully explained. Relief of symptoms is observed irrespective of any changes in the resting or provocable left ventricular outflow gradient. Similarly, changes in left ventricular systolic function, which in general remains unaffected, cannot be the basis for the beneficial response. Slow channel inhibiting agents, however, appear to improve left ventricular diastolic function, the mechanism of which is yet to be elucidated. Nevertheless, improved left ventricular diastolic function may provide an explanation for the relief of some symptoms in patients with hypertrophic cardiomyopathy. The influence of therapy with slow channel inhibiting agents on arrhythmias, sudden death, and on long-term prognosis of patients with hypertrophic cardiomyopathy remains uncertain at the present time and should be the subject of future investigations.

Angiocardiography↗

PubMed1988

Which exercise test variables are of prognostic importance post-myocardial infarction?

The prognostic value of parameters noted on pre-discharge exercise testing was assessed in 300 survivors of acute myocardial infarction. Exercise testing was performed at a mean of 9 days post-infarction. Each patient's data were studied for the presence of ST-segment depression or elevation greater than or equal to 0.1 mV in any of the 12 leads recorded, angina pectoris, exertional hypotension and duration of exercise. The patients were followed for a mean of 12 months and the incidence of death, reinfarction, angina pectoris, heart failure and coronary revascularization procedures was noted. All variables studied, other than the presence of exercise-induced ST-segment elevation, were significantly associated with the occurrence of subsequent cardiac events (P less than 0.001). Exercise-induced ST-segment depression identified 80% of patients who developed complications and was significantly more sensitive than any of the other variables as a prognostic marker (P less than 0.05). The finding of angina pectoris, an abnormal blood pressure response or a limited exercise tolerance in association with exercise-induced ST-segment depression heightened the prognostic implications of this variable.

Angina Pectoris↗

PubMed1997

Comparison of left ventricular responses to the six-minute walk test, stair climbing, and maximal upright bicycle exercise in patients with congestive heart failure due to idiopathic dilated cardiomyopathy.

Submaximal exercise tests have been advocated to assess exercise capacity in chronic heart failure, but hemodynamic responses have not been characterized. To determine left ventricular (LV) responses during submaximal exercise, the LV ejection fraction (EF) and volumes were evaluated by using an ambulatory radionuclide detector in 13 patients with idiopathic dilated cardiomyopathy during upright maximal graded bicycle exercise, stair climbing and a 6-minute walk test. The 3 tests elicited different responses in volumes and, to a lesser degree, in LVEF. The maximal bicycle exercise led to a decrease in LVEF from 22 +/- 9% to 17 +/- 8% (p <0.05), with marked increases in both end-diastolic volume (EDV) (+15 +/- 10%, p <0.001) and end-systolic volume (ESV) (+23 +/- 18%, p <0.001). Stair climbing tended to reduce LVEF (from 24 +/- 11% to 21 +/- 10%, p = 0.05), with a lesser increase in volumes, which was more marked for ESV (+8 +/- 9%, p <0.01) than for EDV (+4 +/- 4%, p <0.01). The 6-minute walk test did not significantly change LVEF (23 +/- 10% vs 22 +/- 10%), but increased both EDV (+10 +/- 6%, p <0.001) and ESV (+8 +/- 8%, p <0.01) moderately and proportionally. Exercise capacity indexes (peak oxygen consumption, maximal bicycle work rate, stair climbing time, and the distance covered during the 6-minute walk test) correlated significantly with one another. There was no correlation between submaximal exercise tolerance indexes and resting or exercise LVEF. This study shows that (1) LVEF changes are inadequate to report on LV volume changes during exercise; (2) the 3 tests induce different LV volume changes; (3) the 6-minute walk test induces significant changes in LV volumes but no change in LVEF.

Adult↗

PubMed1993

Withdrawal of digoxin from patients with chronic heart failure treated with angiotensin-converting-enzyme inhibitors. RADIANCE Study.

BACKGROUND: Although digoxin is effective in the treatment of patients with chronic heart failure who are receiving diuretic agents, it is not clear whether the drug has a role when patients are receiving angiotensin-converting-enzyme inhibitors, as is often the case in current practice. METHODS: We studied 178 patients with New York Heart Association class II or III heart failure and left ventricular ejection fractions of 35 percent or less in normal sinus rhythm who were clinically stable while receiving digoxin, diuretics, and an angiotensin-converting-enzyme inhibitor (captopril or enalapril). The patients were randomly assigned in a double-blind fashion either to continue receiving digoxin (85 patients) or to be switched to placebo (93 patients) for 12 weeks. Otherwise, their medical therapy for heart failure was not changed. RESULTS: Worsening heart failure necessitating withdrawal from the study developed in 23 patients switched to placebo, but in only 4 patients who continued to receive digoxin (P < 0.001). The relative risk of worsening heart failure in the placebo group as compared with the digoxin group was 5.9 (95 percent confidence interval, 2.1 to 17.2). All measures of functional capacity deteriorated in the patients receiving placebo as compared with those continuing to receive digoxin (P = 0.033 for maximal exercise tolerance, P = 0.01 for submaximal exercise endurance, and P = 0.019 for New York Heart Association class). In addition, the patients switched from digoxin to placebo had lower quality-of-life scores (P = 0.04), decreased ejection fractions (P = 0.001), and increases in heart rate (P = 0.001) and body weight (P < 0.001). CONCLUSIONS: These findings indicate that the withdrawal of digoxin carries considerable risks for patients with chronic heart failure and impaired systolic function who have remained clinically stable while receiving digoxin and angiotensin-converting-enzyme inhibitors.

Captopril↗

PubMed1993

Clinical features of an anti-anginal drug in angina pectoris.

Trimetazidine (TMZ) exerts anti-ischaemic effects without any associated central haemodynamic change, both at rest and with exercise. These findings suggest that TMZ has a direct cytoprotective effect, the efficacy of which has been confirmed by clinical studies in effort angina. TMZ as monotherapy when compared with placebo, in acute (60 mg) as well as in chronic (20 mg t.i.d.) administration, significantly improves exercise tolerance: total work, duration of exercise and time to 1 mm ST segment depression, without changing the rate-pressure product. Moreover, during chronic treatment TMZ decreases the rate of anginal attacks. In patients with coronary heart disease insufficiently controlled with nifedipine or a beta-blocker as monotherapy, the addition of TMZ (20 mg t.i.d.) significantly reduces the number of anginal attacks and improves exercise capacity. TMZ antianginal activity in monotherapy has also been compared in double-blind controlled studies with that of a calcium channel antagonist and a beta-blocker as reference drugs. TMZ is as efficient as nifedipine or propranolol on clinical variables as well as on ergometric criteria, but unlike these two reference drugs, which act through a haemodynamic mechanism, TMZ does not decrease rate-pressure product. Furthermore, in the study comparing TMZ with propranolol, TMZ was shown to decrease ischaemic episodes recorded by ECG ambulatory monitoring. These data show that TMZ belongs to the major antianginal agents available today. However, the absence of central haemodynamic effects suggests that the drug has a novel anti-ischaemic mechanism involving direct myocardial cytoprotection.

Adrenergic beta-Antagonists↗

PubMed1988

A randomized placebo controlled, double-blind, crossover trial of transdermal nitroglycerin in stable angina pectoris.

Clinical efficacy of 5 mg per 24 hours transdermal nitroglycerin was studied in a placebo controlled, randomized, double-blind crossover trial, with three days wash-out period at the beginning, in 40 patients with chronic stable angina pectoris during two periods of 14 days. Assessment was carried out by means of a diary method, by the multistage treadmill exercise test, five hours after dosing, and by 24-hour ambulatory ECG recordings. Nitroglycerin patch demonstrated significant improvement of exercise tolerance comparing to placebo, in exercise time to the onset of angina pectoris and ST-segment depression of greater than or equal to 1.0 mm (+45% and +47%), in maximum walking time (+13%), as well as in diminished severity of maximum angina (-38%), in lower maximal ST-segment depression (-32%) and in faster recovery of ST-depression 3 and 6 minutes after the test (-28% and -44%). Nitroglycerin patch showed 33% less angina attacks, mainly severe and moderate, resulting in 37% less sublingual nitroglycerin consumption. A significant fall in the number of ST-segment depression episodes of 1.5 mm or more (-60%) was shown in the 24-hour ECG. All these changes were confirmed to be significant compared to placebo values, at a level of P less than 0.01, by multivariate analysis. This study revealed a positive effect of low dose nitroglycerin patch on improvement of exercise functional capacity and signs of myocardial ischaemia after 14 days of continuous therapy.

Administration, Cutaneous↗

PubMed1998

The effects of exercise training on muscle atrophy in haemodialysis patients.

BACKGROUND: Patients with end-stage renal disease on haemodialysis (HD) have limited work capacity. Many structural and functional alterations in skeletal muscles contribute to this disability. METHODS: To evaluate the effects of exercise training on uraemic myopathy, seven HD patients (mean age 44.1+/-17.2 years) were studied. Open muscle biopsies were taken from their vastus lateralis muscle before and after a 6-month exercise rehabilitation programme and examined by routine light- and transmission electron-microscopy. Histochemical stainings of frozen sections were performed and morphometric analysis was also applied to estimate the proportion of each fibre type and the muscle fibre area. Spiroergometric and neurophysiological testing and peak extension forces of the lower limbs were measured before and after exercise training. RESULTS: All patients showed impaired exercise capacity, which was associated with marked muscular atrophy (mean area 2548+/-463 microm2) and reduction in muscle strength and nerve conduction velocity. All types of fibres were atrophied, but type II were more affected. The ultrastructural study showed severe degenerative changes in skeletal muscle fibres, mitochondria, and capillaries. Exercise training had an impressive effect on muscular atrophy; in particular the proportion of type II fibres increased by 51% and mean muscle fibre area by 29%. Favourable changes were also seen on the structure and number of capillaries and mitochondria. These results were confirmed by a 48% increase in VO2 peak and a 29% in exercise time, as well as an improvement in the peak muscle strength of the lower limbs and in nerve conduction velocity. CONCLUSIONS: Skeletal muscle atrophy in HD patients contribute to their poor exercise tolerance. The application of an exercise training rehabilitation programme improved muscle atrophy markedly, and therefore had beneficial effects in overall work performance.

Adult↗

PubMed2004

Endothelial markers in chronic heart failure: training normalizes exercise-induced vWF release.

BACKGROUND: Chronic heart failure (CHF) is characterized by endothelial dysfunction. Vascular endothelium is important for control of haemostasis and vasoregulation. The aim of the present study was to investigate plasma levels of several endothelial markers and the exercise-induced changes on these plasma levels in CHF patients. Subsequently, the effect of a 6-month training programme on these markers is described. MATERIALS AND METHODS: Twenty-nine male CHF patients (NYHA II/III, age 60 +/- 8 year, body mass index 26.7 +/- 2.3 kg m(-2), left ventricular ejection fraction 26.3-7.2%; mean +/- SD) participated. Patients were randomly assigned to a training or control group. Training (26 weeks; combined strength and endurance exercises) was four sessions/week: two sessions supervised and two sessions at home. Before and after intervention, anthropometry, endothelial markers (haemostasis and vasoregulation), maximal workload and peak oxygen uptake were assessed. RESULTS: Physical training positively affected maximal workload. Plasma levels of endothelial markers were not affected by physical training and not related to exercise tolerance. After training, stimulated (maximal exercise) plasma von Willebrand Factor (vWF) release was present, whereas at baseline this release was absent. CONCLUSION: Physical training led to normalization of the stimulated plasma vWF release. Plasma levels of other endothelial markers were not affected by physical training either at rest or under stimulated (maximal exercise) conditions.

Aged↗

PubMed1987

The use of the right gastro-epiploic artery in coronary artery bypass grafting.

Thirty consecutive patients with angina pectoris undergoing coronary artery bypass grafting using the proximally attached right gastro-epiploic artery are described. Posterior coronary arteries were grafted using the right gastro-epiploic artery, and grafts to the left coronary artery were done using predominantly internal mammary artery grafts. The right gastro-epiploic artery graft is mobilized along the greater curvature of the stomach, and transected distally. With cardiopulmonary bypass and blood cardioplegic arrest for myocardial preservation during cross-clamping of the aorta, the distal end of the artery is anastomosed end-to-side to the posterior descending artery or a postero-lateral branch, or to both, using a sequential technique. Twenty-five of the patients complained of symptoms suggestive of angina early postoperatively but are currently symptom-free with normal exercise tolerance. Thirteen patients had postoperative exercise tests: eight were normal, two were inconclusive, and three were abnormal. Nine grafted coronary arteries were re-angiogrammed, and seven were judged to be patent. It is concluded that, as an alternative resource, the right gastro-epiploic artery can be used to bypass coronary obstructions expeditiously and with results comparable to those obtained with the saphenous vein or internal mammary artery.

Adult↗

PubMed1984

Isolation of Streptococcus pneumoniae type 3 from equine species.

Streptococcus pneumoniae type 3 was isolated from seven tracheobronchial aspirates and one pleural tap of seven adult horses and one foal. There was no direct evidence in these horses that isolation of the pneumococcus was related to a specific disease syndrome. Presenting complaints included two horses with chronic cough, two horses with decreased exercise tolerance, one horse with exercise-induced pulmonary hemorrhage, and three horses with pneumonia. Antibiotic therapy resolved the primary clinical complaint. This is the first report of the isolation of S. pneumoniae type 3 from adult horses.

Animals↗

PubMed1991

Biochemical characterization of exercise-trained porcine myocardium.

The purpose of this study was to determine whether cardiac biochemical adaptations are induced by chronic exercise training (ET) of miniature swine. Female Yucatan miniature swine were trained on a treadmill or were cage confined (C) for 16-22 wk. After training, the ET pigs had increased exercise tolerance, lower heart rates during exercise at submaximal intensities, moderate cardiac hypertrophy, increased coronary blood flow capacity, and increased oxidative capacity of skeletal muscle. Myosin from both the C and ET hearts was 100% of the V3 isozyme, and there were no differences between the myosin adenosine triphosphatase (ATPase) or myofibrillar ATPase activities of C and ET hearts. Also, the sarcoplasmic reticulum Ca(2+)-ATPase activity and Na(+)-Ca2+ exchange activity of sarcolemmal vesicles were the same in cardiac muscle of C and ET hearts. Finally, the glycolytic and oxidative capacity of ET cardiac muscle was not different from control, since phosphofructokinase, citrate synthase, and 3-hydroxyacyl-CoA dehydrogenase activities were the same in cardiac tissue from ET and C pigs. We conclude that endurance exercise training does not provide sufficient stress on the heart of a large mammal to induce changes in any of the three major cardiac biochemical systems of the porcine myocardium: the contractile system, the Ca2+ regulatory systems, or the metabolic system.

Aging↗

PubMedDate not supplied

Pulmonary function testing in interstitial lung diseases.

Interstitial lung diseases (ILDs) are functionally characterized by a restrictive ventilatory defect due to a reduced distensibility of the lung parenchyma. ILD patients also show a reduced exercise tolerance, the main factors limiting exercise capacity being ventilatory and gas exchange abnormalities. Functional abnormalities in ILDs are typical, but not specific. Despite the fact that different lung function patterns have been described among ILDs, they overlap and their practical application to differentiate ILDs is poor. Resting pulmonary function and exercise-induced hypoxemia can aid in defining the prognosis of ILDs and in referring patients for lung transplantation. Additionally, spirometry and diffusing capacity are useful to monitor the response of patients to therapy.

Humans↗

PubMed1979

Comparison of clinical effects of propranolol (Inderal) with once daily slow-release oxprenolol (Slow Trasicor) in angina pectoris.

In a double-blind, crossover, randomized study, the therapeutic effectiveness of a single daily dose of slow-release oxprenolol (160 mg/day) was compared with a conventional dosage schedule of propranolol (40 mg three times daily) in eighteen patients with uncomplicated, stable exercise-induced angina pectoris. Compared to control values both drugs produced equipotent reduction in the frequency and severity of anginal attacks accompanied by a significant increase in exercise tolerance, a significant suppression of exercising heart rate and an appreciable reduction in the electrocardiographic evidence of myocardial ischaemia when tested on a treadmill. The possible advantages offered by a single dose treatment with slow-release oxprenolol are discussed.

Adult↗

PubMed2005

Pulmonary function tests fail to predict exercise intolerance in sheep with emphysema.

PURPOSE: The purpose of this study was to examine ventilatory parameters, gas exchange, and exercise tolerance in sheep undergoing cardiopulmonary exercise testing and pulmonary function testing at baseline and after induction of emphysema using nebulized papain, to improve our understanding of the contributions of parenchymal emphysema with minimal airway disease to exertional dysfunction in mild-to-moderate emphysema. METHODS: Static lung physiology (total lung capacity, residual volume, static elastance, and diffusing capacity of carbon monoxide) and lung (ZL) input impedance were measured, and cardiopulmonary exercise testing (CPET) was performed in 12 sheep before and after induction of emphysema. Papain treatment was delivered over a 12-wk period, as a single dose per week, to induce mild-to-moderate emphysema without airway disease. Static and dynamic lung physiology, as well as CPET, were then repeated. RESULTS: At the emphysema time point (EMPH), all animals were asymptomatic for emphysema at rest. There was a 60% increase in residual volume and a 57% decrease in static elastance, accompanied by a 36% reduction in diffusing capacity. Airway resistance was consistently, mildly increased, resulting in an increased expiratory time constant for all sheep at EMPH. There were no significant differences at EMPH versus baseline for any measured physiological variables during CPET (VO2peak, VCO2peak, RER, anaerobic threshold, O2 pulse, tidal volume, peak flow, peak VE/VO2, or peak VE). CONCLUSION: There is notable conservation of exercise capacity in sheep with mild-to-moderate parenchymal emphysema; this is not predicted by pulmonary function tests. In the absence of significant airway narrowing, mild-to-moderate emphysema is unlikely to result in airflow limitation.

Animals↗

PubMed1992

Supplemental oxygen and exercise performance in patients with cystic fibrosis with severe pulmonary disease.

Patients with cystic fibrosis (CF) and advanced pulmonary disease have pulmonary limitation of exercise, often associated with arterial oxygen desaturation. Improving oxygenation during exercise by providing supplemental oxygen may improve exercise performance in these patients. To test this, we performed graded exercise stress tests in 22 CF patients with severe pulmonary disease (mean PaO2, 64 +/- 2 mm Hg [+/- SE]; PaCO2 46 +/- 2 mm Hg; RV/TLC, 57 +/- 4 percent; FEV1, 38 +/- 4 percent of predicted; FEF25-75%, 13 +/- 2 percent of predicted; median age, 26 years) and compared them to 21 controls (RV/TLC, 27 +/- 4 percent; FEV1, 112 +/- 2 percent of predicted; FEF25-75%, 80 +/- 4 percent of predicted; median age, 29 years). Each subject performed graded exercise stress tests while breathing FIO2 of 0.21 and FIO2 of 0.30. Subjects were blinded to the composition of the inspired gas, and the order of testing was randomized. We found that CF subjects exercised longer, had a higher maximal VO2, higher O2 pulse, and less arterial oxygen desaturation when receiving supplemental O2. Control subjects exercised longer when breathing supplemental O2 but had no significant change in maximal VO2, O2 pulse, or SaO2. Both CF and control subjects had increased end-tidal PCO2 when exercising while breathing supplemental O2. We conclude that CF patients with advanced pulmonary disease have increased exercise tolerance and aerobic capacity when exercising while breathing supplemental O2.

Adolescent↗