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PubMed1981

Carbon monoxide and exercise tolerance in chronic bronchitis and emphysema.

The effects of carbon monoxide on exercise tolerance as assessed by the distance walked in 12 minutes were studied in 15 patients with severe chronic bronchitis and emphysema (mean forced expiratory volume in one second 0.56 1, mean forced vital capacity 1.54 1). Each subject walked breathing air and oxygen before and after exposure to sufficient carbon monoxide to raise their venous carboxyhaemoglobin concentration by 9%. There was a significant reduction in the walking distance when the patients breathed air after exposure to carbon monoxide (p less than 0.01), and the significant increase in walking distance seen after exercise when breathing oxygen at 2 1/minute via nasal cannulae was abolished if carbon monoxide has previously been administered. Thus concentrations of carboxyhaemoglobin frequently found in bronchitic patients who smoke may reduce their tolerance of everyday exercise, possibly by interfering with the transport of oxygen to exercising muscles.

Bronchitis↗

PubMed1992

[Pulmonary function and exercise tolerance in patients treated with bone marrow transplantation (BMT)].

We assessed pulmonary function and exercise tolerance in 10 BMT patients. Their underlying disorders were as follows; chronic myeloid leukemia 5 cases, acute lymphoblastic leukemia 2 cases, aplastic anemia, acute myeloid leukemia and non-Hodgkin's lymphoma one case each. Their mean age was 26 +/- 9 years old. When the patients were healthy and free of serious complications and anemia, arterial blood gas examination, pulmonary function tests and incremental treadmill exercise test were examined repeatedly. Although %VC and FEV1.0% kept within normal range, PaO2 at rest, %DLCO, VO2max, VO2max/kg and O2-pulsemax remained low at one year after BMT. There were significant correlations between VO2max and O2-pulsemax [r = 0.955 (p < 0.001)], %VC [r = 0.758 (p < 0.02)], VE/VO2max [r = -0.749 (p < 0.02)] and delta SaO2/VO2/kg [r = -0.731 (p < 0.02)], suggesting that exercise intolerance in BMT patients may be based on both cardiac and gas exchange abnormalities. To evaluate cardiac dysfunction, we compared exercise parameters obtained at an exercise level of 75% predicted heart rate max in five age-matched normal subjects to those in six BMT patients who did not demonstrate desaturation during exercise. As a result, the mean values of VO2max/kg and O2-pulse/m2 in BMT patients were significantly lower than those in normal subjects, suggesting that cardiac dysfunction may be due to insufficiency of stroke volume during exercise. It is concluded that exercise intolerance in BMT patients may be mainly due to cardiac dysfunction.

Adolescent↗

PubMed1988

Exercise tolerance and disease related measures in patients with rheumatoid arthritis and osteoarthritis.

One hundred and twenty patients with symptomatic rheumatoid arthritis (RA) or osteoarthritis (OA) in weight bearing joints (RA = 40; OA = 80) performed subjective maximal graded exercise tests on a motor driven treadmill. Disease related measures were also assessed. Findings from this sample indicated that people with arthritis were significantly impaired in exercise tolerance, flexibility and biomechanical efficiency. Significant differences between diagnoses appeared on a number of disease related measures; however, there was little correlation between disease related measures and exercise tolerance. Women demonstrated a greater aerobic impairment than men; and women with RA had a greater aerobic deficit than women with OA.

Arthritis, Rheumatoid↗

PubMed1990

[Effect of nitrates on left ventricular function and exercise tolerance in patients with mild circulatory failure caused by ischemic heart disease].

In 26 patients with ischaemic heart disease with symptoms of mild chronic circulatory failure (NYHA grade II) aged 56.2 +/- 14.4 years the left ventricular function was tested by two-dimensional echocardiography, the exercise tolerance was determined on cycle ergometer at submaximal workloads, the cardiothoracic index (CTI) and cardiac volume index (CVI) were calculated from chest radiograms. The tests were done before and after 2 and 6 weeks of treatment with isosorbide dinitrate in doses of 49.6 +/- 15.2 mg/day. Isosorbide was found to increase somewhat the ejection fraction (EF), and to raise statistically significantly (p less than 0.05) the velocity of shortening of the circumferential fibres in left ventricular myocardium (mVCF), and to reduce the internal dimensions of the left ventricle (LVIDd and LVIDs), without changing the values of the ejection index (SVI) and cardiac index (CI). Decreased transverse dimensions of the left ventricle was correlated with a significant decrease of the CVI index. No statistically significant effect of isosorbide was noted on the parameters characterizing exercise tolerance but the quotient of the exercise-induced heart rate by the workload (HR/Wat) and the index of myocardial oxygen requirement (HRx Ps) were decreased in a demonstrable way.

Adult↗

PubMed1981

The effect of pindolol and isosorbide dinitrate and their combination on exercise tolerance and ECG changes in angina pectoris.

The effect of placebo, isosorbide dinitrate (ISDN) (5 mg orally), pindolol (1.0 mg i.v.) and the combination of ISDN and pindolol was tested in 12 patients with stable, exercise-induced angina pectoris and normal resting ECG. A graded submaximal exercise test was performed on a bicycle ergometer 30 min after medication. All patients had ST depression during and shortly after exercise. ISDN and pindolol increased exercise tolerance to a similar degree but through different mechanisms. Pindolol decreased heart rate and markedly reduced ST depression in the ECG, while ISDN had no effect on ECG changes. The combination of ISDN and pindolol was superior to either drug alone in increasing exercise tolerance in angina pectoris.

Angina Pectoris↗

PubMed1994

Echo Doppler diastolic function and exercise tolerance.

OBJECTIVE: To investigate the possible association between Doppler left ventricular filling pattern and exercise capacity in a group of normotensives to severe hypertensive patients. BACKGROUND: Invasive left ventricular filling indexes evaluated at rest are reported to be related to exercise capacity in heart failure. Whether exercise capacity is limited by abnormalities of left ventricular filling also in other less severe conditions is however unclear. METHODS: Fifty-one subjects with normal to severely elevated blood pressure underwent a standard exercise test on cycle ergometer, negative for myocardial ischemia, and a complete echo Doppler evaluation showing a basal systolic function within normal limits. RESULTS: Basal systolic function indexes were not significantly related to exercise duration. On the contrary, exercise duration was highly significantly correlated to the relative atrial contribution to left ventricular filling (0.001 < P < 0.05), in both the overall group and the two subgroups in whom exercise was interrupted because of fatigue (n = 30) or because of attaining target heart rate (n = 21). Significant correlations were also observed between exercise time and resting blood pressure, whereas no association with resting heart rate, age and body surface area was found. Exercise time also correlated to left ventricular mass and mass index but not to left ventricular volume. Multiple regression analysis showed that exercise tolerance was significantly related to diastolic blood pressure and left ventricular filling. Echo Doppler indexes of left ventricular filling are associated with exercise duration; left ventricular diastole could thus influence effort tolerance, not only in patients with cardiac insufficiency, but also in subjects with normal to elevated blood pressure levels and normal systolic function at rest.

Blood Pressure↗

PubMed2000

Postoperative exercise tolerance after aortic valve replacement by small-size prosthesis: functional consequence of small-size aortic prosthesis.

OBJECTIVES: The objective of this study was to determine whether a small-size valve prosthesis contributes to exercise intolerance, as assessed by VO2 measurement during an exhaustive cycle ergometer exercise. BACKGROUND: The determinants of exercise capacity after mechanical aortic replacement are not well known. The selection of small valve sizes has, however, been described as an independent predictor of exercise intolerance as assessed by exercise duration. Maximal oxygen uptake (VO2max) is a good index of exercise tolerance. METHODS: Fourteen patients were eligible, with a mean age of 62 +/- 6 years. Before surgery, the mean left ventricular ejection fraction (LVEF) was 73 +/- 8%. Two valve types with small diameter (19 to 21 mm) were used: Medtronic Hall and St Jude Medical. A healthy sedentary control group (n = 14) paired for age, weight and size was constituted. After one year of follow-up, cardiorespiratory tests were performed. In addition, the gradients through the prostheses were determined by continuous pulse Doppler at rest and immediately after the cardiorespiratory test. RESULTS The exercise tolerance was not significantly different between the control group and patient group: VO2 peak (21.7 vs. 20.4 ml/kg/min; p = 0.42), workloads (115 vs. 93 W; p = 0.13) and ventilatory parameters were similar. The mean and peak gradients at rest and during exercise were not correlated with VO2max. CONCLUSIONS: Valve replacement by small aortic prosthesis does not seem to be a factor of exercise intolerance as assessed by VO2max in patients without LVEF dysfunction before surgery.

Aged↗

PubMed1989

Recombinant human erythropoietin: impact on brain and cognitive function, exercise tolerance, sexual potency, and quality of life.

The clinical manifestations of uremia are only incompletely reversed by chronic hemodialysis. Signs and symptoms can include abnormalities in electrophysiologic indices, clinical mental status, and neuropsychological test performance, as well as decreases in exercise tolerance, sexual potency, and general quality of life. Though retention of uremic toxins is responsible for many of these symptom complexes, some may be caused, or substantially aggravated, by the anemia that almost invariably accompanies chronic renal failure. Treatment with recombinant human erythropoietin (r-HuEPO; EPOGEN [epoetin alfa], AMGEN Inc, Thousand Oaks, CA) increases hematocrit values and thus reduces the anemia, in turn improving brain and cognitive function, exercise tolerance, sexual potency, and quality of life.

Anemia↗

PubMed1984

Randomized, placebo-controlled evaluation of lidoflazine in patients receiving beta-blocker therapy with propranolol: improvement in anginal symptoms and exercise tolerance with combined drug therapy.

Twenty-nine patients symptomatic despite beta-blocker therapy were entered into a randomized, double-blind, placebo-controlled, crossover trial of lidoflazine added to propranolol. After clinically documented beta blockade was achieved, patients were randomized to either propranolol plus placebo (P) or propranolol plus lidoflazine (L). Patients initially receiving lidoflazine (group with treatment sequence LP) showed improvement in exercise tolerance from propranolol alone (7.2 to 9.3 minutes, p less than 0.05). Those randomized initially to propranolol plus placebo (group with treatment sequence PL) had unchanged exercise tolerance (7.3 minutes). After 4 months, patients were crossed over to the alternative form of therapy. Patients (group PL) now receiving lidoflazine in addition to propranolol increased their exercise duration (7.8 minutes), but not, significantly. However, patients switched to propranolol plus placebo (group LP) continued to sustain their improved exercise capacity, showing a "carryover" effect. Symptomatic improvement was manifested by a statistically significant reduction in both anginal attack rate and nitroglycerin consumption. The therapeutic efficacy of combined therapy was associated with further blunting of the heart rate response to exercise achieved by beta blockade alone. The combination of agents was well tolerated.

Angina Pectoris↗

PubMed1989

Effects of atenolol, verapamil, and xamoterol on heart rate and exercise tolerance in digitalised patients with chronic atrial fibrillation.

The aim of the study was to compare the effects of atenolol (50 mg b.i.d.), verapamil (80 mg b.i.d.), xamoterol (200 mg b.i.d.), and matching placebo on heart rate (HR) and exercise tolerance in digitalised patients with chronic atrial fibrillation. Each treatment was taken for 4 weeks, and digoxin was continued throughout the study. During treatment with placebo (digoxin alone), the mean postexercise heart rate was 164 beats/min, and four subjects had rates of greater than or equal to 170 beats/min. Atenolol, verapamil, and xamoterol achieved significantly better control of exercise-induced tachycardia, mean postexercise heart rates being reduced to 120, 131, and 130 beats/min, respectively (p less than 0.01 for each). However, minimum HRs less than or equal to 45 beats/min occurred during treatment with placebo, atenolol, and verapamil, whereas treatment with xamoterol was associated with a minimum heart rate of 56 beats/min. Treatment with atenolol was associated with a marked reduction in maximum treadmill walking distance (mean 356 m) as compared both with placebo (mean 421 m, p less than 0.01) and verapamil (mean 439 m, p less than 0.01). Xamoterol reduced maximum walking distances as compared with verapamil (402 vs. 439 m; p less than 0.05) but not placebo (402 vs. 421 m; NSS). Thus, atenolol, verapamil, and xamoterol achieved better control of exercise-induced tachycardia than digoxin, but atenolol clearly impaired exercise tolerance whereas verapamil did not. Xamoterol achieved more even control of ventricular response rates and prevented the resting bradycardias that occurred with the other treatments. However, walking distances were significantly lower than those noted during treatment with verapamil.

Adrenergic beta-Agonists↗

PubMed1999

Central and peripheral components of chronic heart failure: determinants of exercise tolerance.

This study sought to determine the relationship between myocardial dysfunction and peripheral haemodynamic disorders to exercise intolerance in patients with chronic heart failure (CHF). Seventeen patients with mild to moderate CHF (peak oxygen consumption (VO2) >16 ml/min/kg) and 13 with severe CHF (peak VO2 <16 ml/min/kg) underwent invasive (Swan-Ganz) cardiopulmonary exercise testing and forearm venous occlusion plethysmography at rest and during maximal dilatation in reactive hyperaemia. There was a shift from central to peripheral haemodynamic factors limiting exercise, suggesting an increasing importance of peripheral factors in parallel to the progression of CHF. In mild to moderate CHF peak VO2 was closely related to central haemodynamics (r = 0.57 for cardiac index at rest; r = 0.76 for cardiac index at maximal workload; r = -0.54 for right arterial pressure at maximal workload; all p<0.05) and poorly correlated with peripheral haemodynamics (blood flow, vascular resistance and venous tone). In contrast, in severe CHF peak VO2 was closely related to peripheral haemodynamic factors (r = 0.79 for forearm blood flow; r = -0.82 for vascular resistance; r = -0.77 for venous tone; all p<0.05) and less to central ones. Thus, exercise tolerance of patients with mild to moderate CHF is predominantly determined by central haemodynamic factors, notably by the cardiac index. In severe CHF peripheral factors assume ever greater importance in the determining of exercise capacity.

Adult↗

PubMed1985

Exercise tolerance in coronary patients: randomized trial of two-week treatment with molsidomine versus placebo.

Using a randomized, double-blind, crossover protocol, we compared the effects of oral molsidomine (Corvaton, 6 mg/day) and placebo, administered alternately for two 14-day periods, on the exercise tolerance of 25 outpatients with coronary heart disease. Resting heart rate and oxygen consumption increased by 6.8% (p less than 0.005) and 12.6% (p less than 0.01), while peripheral systolic blood pressure was reduced by 5.1% (p less than 0.05). At submaximal workloads, systolic and diastolic blood pressures were reduced by 5.6% (p less than 0.001) and 6.1% (p less than 0.001), the pressure-rate product was reduced by 8.5% (p less than 0.05), and ST segment depression was reduced by 40.0% (p less than 0.005). At maximal exercise level, mechanical power increased by 32.4% (p less than 0.001) and oxygen consumption by 15.5% (p less than 0.005), while ST segment depression was reduced by 30.6% (p less than 0.001). No alteration was found in postexercise lung function tests. It is concluded that molsidomine reduces myocardial ischemia at both submaximal and maximal work levels and increases exercise tolerance significantly. These effects could be related to reduced myocardial oxygen requirements, reflected in a lower pressure-rate product at submaximal exercise and perhaps enhanced by a lower preload, which, moreover, would favor coronary flow in subendocardial layers. The drug has no adverse bronchopulmonary effects.

Adult↗

PubMed1985

Working ability and exercise tolerance during treatment of mild hypertension. II. A comparison between atenolol and prazosin medication.

The treatments of mild hypertension with atenolol and prazosin in occupationally active men and women were compared in a double blind cross-over with placebo. The hypotensive effect of the beta-adreno-receptor blocking drug, atenolol, were striking and in accordance with current knowledge, using one daily dose of 100 mg. In contrast, the hypotensive effect of taking 2 mg prazosin twice a day was modest, averaging about 3% when compared with placebo, somewhat less but still detectable during the performance of muscular exercises. Atenolol medication significantly reduced heart rate and blood pressure responses to muscular exercises, covering a range of work loads experienced during ordinary working days. No increased feeling of muscular fatigue or other discomfort during muscular work compared to that on prazosin and placebo medication could be detected. It was therefore concluded that atenolol medication was a useful treatment of mild hypertension and did not reduce the normal working ability and exercise tolerance. Prazosin medication did not significantly change working ability and exercise tolerance.

Adult↗

PubMed1980

[Sustained effect of nitroglycerin ointment on exercise tolerance in patients with effort angina (author's transl)].

The effect on exercise tolerance of nitroglycerin (NTG) ointment was studied by exercise test on bicycle ergometer in a selected group of patients with effort angina and angiographically proven critical coronary lesions. NTG ointment (15 mg) and placebo were administered in a double-blind cross-over randomized trial on two consecutive days; exercise test was carried out before the administration of NTG ointment and placebo, and repeated after one hour, 2 and 1/2 hours and 4 hours. Compared to control and placebo tests, NTG ointment produced a highly significant increase of duration of exercise and of total work load in all tests, as well as a significant decrease of maximal ST segment depression. After NTG ointment administration resting systolic blood pressure showed a significant decrease after one hour, 2 and 1/2 hours and 4 hours, resting heart rate a significant increase after 2 and 1/2 and 4 hours, and peak exercise heart rate a significant increase after 4 hours. Double product at rest was unaffected by NTG ointment, while at peak exercise it showed a significant increase only after 4 hours. Our data show that in patients with effort angina NTG ointment produces an important increase of exercise capacity which persists at least for 4 hours after the administration. Therefore NTG ointment seems to be of high value in the treatment of effort angina.

Adult↗

PubMed1986

Effects of digoxin, placebo and ibopamine on exercise tolerance and cardiac rhythm of patients with chronic post-infarct left ventricular failure.

This study compares the effects of digoxin, placebo and ibopamine (SB-7505), the orally active 3,4-diisobutyryl ester of N-methyl-dopamine, on exercise tolerance and cardiac rhythm of 14 patients whose left ventricular heart failure (end-diastolic pressure, 26.3 +/- 5.9 mmHg; ejection fraction, 0.42 +/- 0.10%) depended on a previous myocardial infarction. Patients were admitted to the study while on chronic oral digoxin treatment (serum levels between 1.1 and 1.9 ng/ml). Placebo instead of digoxin was given for the following month. Thereafter ibopamine 50 mg t.i.d. for one month was given. A sequence of one-month treatments with digoxin, placebo and ibopamine was repeated, then ibopamine was administered continuously for the next two months. The concurrent treatment (diuretics in all patients, nitroderivates in twelve, calcium antagonists in two) remained unchanged during the observation period. Symptoms-limited exercise tests and 24-h Holter recordings were obtained at admission, at the end of each one-month treatment and at the end of the observation period. Two patients developed unstable angina without increase of serum creatine phosphokinase while on ibopamine and were withdrawn. Out of the 12 patients that concluded the trial, one required supplementary doses of diuretic at the end of the second period on placebo. The results obtained during the trial suggest that: a) therapeutic plasma levels of digoxin have no deleterious effect on cardiac rhythm nor significantly increase exercise tolerance as compared with placebo; b) diuretics and nitrates appear to sustain the clinical stability of these patients as a group.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1992

[Physical exercise tolerance in chronic obstructive emphysematous bronchitis and coronary heart disease under antiobstructive therapy].

19 consecutive patients (18 men, one woman, mean age 61.4 [49-73]years) with chronic obstructive airways disease (bronchitis and emphysema) together with angiographically confirmed coronary heart disease were studied to investigate their cardiopulmonary exercise tolerance and the effects of bronchodilators on their myocardial ischaemia. Because they were receiving drug therapy for angina or because they had previously undergone aortocoronary bypass operation or balloon dilatation, the patients were symptom-free. In three cases slight ischaemia was demonstrable during maximal exertion. Aerobic and anaerobic exercise capacity was determined by spiroergometry after inhalation of salbutamol (S, 0.2 mg) alone or in combination with oxitropium bromide (O, 0.2 mg). The supplementary effect of oral theophylline (T, 15 mg/kg.day) was studied in 13 patients. In terms of maximal aerobic exercise tolerance the following improvements were noted: energy output (watts): S: + 6.3%; S and O: + 12.3% (P < 0.05); S, O and T: + 14.0% (P < 0.01). Oxygen uptake (ml/min): S: + 8.2% (P < 0.05); S and O: + 18.2% (P < 0.01); S, O and T: + 35.4% (P < 0.01). Maximum exercise capacity was not significantly improved, although maximum oxygen uptake was significantly increased by the two-drug combination by 16.9% (P < 0.05) and by the three-drug combination by 19.2% (P < 0.05). Maximum minute volume and tidal volume rose significantly, though respiratory rate was unchanged. Heart rate and blood pressure remained practically unaffected by the treatment, both at rest and during exertion. There was no evidence of significant aggravation of ventricular arrhythmias or of ischaemia during ergometric testing.

Albuterol↗

PubMed1997

[Myosin isoforms in skeletal muscle in patients with chronic heart decompensation: distribution and correlation with with exercise tolerance].

Chronic heart failure (CHF) is accompanied by a reduced exercise capacity, and the symptoms can be at least in part explained by qualitative and quantitative changes in the skeletal muscle composition and metabolism. We have correlated the myosin heavy chain (MHC) composition of the gastrocnemius in 20 patients with different degrees of CHF to expiratory gases measured during maximal cardiopulmonary exercise testing, NYHA functional class and echocardiographic parameters. MHC composition was determined electrophoretically in skeletal muscle needle microbiopsies and the percent distribution calculated by laser densitometry. There was no correlation between ejection fraction, left ventricular end-diastolic and end-systolic diameters and MHC composition. The percentage of MHC 1 (slow aerobic isoform) was positively correlated with peak VO2 (r2 = 0.5, p = 0.0004), ventilatory threshold (VT, r2 = 0.33, p = 0.008), and O2 pulse (peak VO2/HR, r2 = 0.40, p = 0.003). There was a negative correlation between MHC 2a and 2b (fast isoforms) and peak VO2 (r2 = 0.38 and 0.37, p = 0.004, respectively), VT (r2 = 0.2, p = 0.05; r2 = 0.34, p = 0.007, respectively) and O2 pulse (r2 = 0.39, p = 0.003; r2 = 0.23, p = 0.03, respectively). NYHA functional class was also negatively correlated with the same parameters (r2 = 0.2, p = 0.01; r2 = 0.4, p = 0.001; r2 = 0.34, p = 0.006, respectively) as well as with MHC 1 (r2 = 0.62, p = 0.0001). A positive correlation was found between NYHA functional class and MHC 2a and 2b (r2 = 0.46, p = 0.001; r2 = 0.41, p = 0.002, respectively). The severity of heart failure is paralleled by a shift of the MHC pattern toward the fast MHC 2b. The correlation between the magnitude of the MHCs shift, from the slow aerobic to the fast type, with both clinical parameters (NYHA functional class) and functional measurements (peak VO2, VT, O2 pulse) of exercise capacity seem to suggest that changes in skeletal muscle composition may play a key role in exercise tolerance in patients with CHF.

Aged↗

PubMed1990

Dissociation of exercise tolerance and total myocardial ischemic burden in chronic stable angina pectoris.

Exercise treadmill tests and ambulatory monitoring were used in a double-blind, placebo-controlled, double-dummy crossover comparison of nifedipine (10 mg, 3 times daily) and transdermal nitroglycerin (15 mg). All patients (n = 20) had chronic stable angina with symptomatic and silent events. All patients had 3 episodes of angina/week and 3 episodes of ischemia/24 hr. The protocol was made up of 2 weeks of placebo followed by 2 weeks of active drug, then crossed over for 2 weeks of placebo followed by the other active drug. At the end of each 2-week period, patients had ambulatory monitoring and exercise treadmill testing. All ambulatory monitoring reports were read blind and entered into an independent data base. The results were the following: on transdermal nitroglycerin, the duration of ischemia decreased by 57% from 140 min/24 hr to 60 min/24 hr (p = 0.0054). The exercise time increased by 5.5% from 4.8 to 5.0 minutes (p = 0.16). With nifedipine, the duration of ischemia decreased by 22% from 175 min/24 hr to 137 min/24 hr (p = 0.16). The exercise tolerance time increased by 13% from 4.5 to 5.0 minutes (p = 0.0264). Nifedipine increased exercise time without altering total ischemic time, while transdermal nitroglycerin decreased total ischemic time without increasing exercise time. Thus, changes in exercise time do not necessarily predict changes in total ischemic time.

Administration, Cutaneous↗