SEARCH · PubMed Health

Results for “exercise capacity”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources

PubMed1984

Relation of right ventricular ejection fraction to exercise capacity in chronic left ventricular failure.

Although the left ventricle is traditionally viewed as the heart's main pumping chamber, no correlation has been shown between left ventricular (LV) ejection fraction (EF) at rest and exercise capacity in patients with chronic LV failure. Because vasodilators with venodilating activity increase exercise capacity more than predominant arterial dilators in patients with LV failure, right ventricular (RV) function may relate to exercise capacity in these patients. In 25 patients with chronic LV failure, caused by coronary artery disease in 12 patients and idiopathic dilated cardiomyopathy in 13 patients, RVEF and LVEF at rest were measured by radionuclide angiography. Maximal upright bicycle exercise testing was also performed to determine maximal oxygen consumption, which averaged only 13 +/- 4 ml/min/kg. The LVEF at rest was 26 +/- 10% and did not correlate with maximal oxygen consumption (r = 0.08). However, the RVEF was 41 +/- 12% and correlated with maximal oxygen consumption (r = 0.70, p less than 0.001) in the same patients. The correlation was stronger (r = 0.88) in patients with coronary artery disease than in those with idiopathic dilated cardiomyopathy (r = 0.60). Thus, RVEF at rest is more predictive of exercise capacity than LVEF in the same patients with chronic LV failure. These results are consistent with the clinical observation that only venodilating agents increase exercise capacity of patients with chronic LV failure.

Cardiac Output↗

PubMed1988

Exercise haemodynamics and maximal exercise capacity during beta-adrenoceptor blockade in normotensive and hypertensive subjects.

1. The effects of atenolol administration on maximal exercise capacity and exercise haemodynamics have been compared in eight normotensive and eight mildly hypertensive subjects, matched for sex, age, body weight, and maximal oxygen uptake, and familiar with maximal exercise testing. 2. Supine and exercise blood pressure, and exercise total peripheral resistance were significantly higher, and exercise cardiac output was significantly lower in the hypertensive than in the normotensive subjects. 3. Administration of atenolol (1 X 100 mg day-1) for 3 days reduced supine and exercise systolic blood pressure, heart rate, and cardiac output, and increased exercise stroke volume. Supine and exercise diastolic blood pressure and exercise total peripheral resistance were unaffected by atenolol. The effects of atenolol did not differ in the normotensive and the hypertensive subjects. 4. Maximal work load, maximal oxygen uptake, and maximal heart rate were reduced to a similar extent in normotensive and hypertensive subjects during atenolol treatment. 5. It is concluded that there is no difference in the effects of short-term atenolol administration on exercise haemodynamics and maximal exercise capacity in normotensive and mildly hypertensive subjects.

Adrenergic beta-Antagonists↗

PubMedDate not supplied

Recombinant growth hormone therapy in patients with ischemic cardiomyopathy : effects on hemodynamics, left ventricular function, and cardiopulmonary exercise capacity.

BACKGROUND: We studied the effects of recombinant growth hormone (rhGH) on exercise capacity and cardiac function in patients with ischemic cardiomyopathy. METHODS AND RESULTS: Seven patients (aged 55+/-9 years) with mild to moderate congestive heart failure (ejection fraction 31+/-4%) who were on standard therapy were included. The patients were studied at baseline, after 3 months of rhGH treatment, and 3 months after rhGH discontinuation. Cardiac function was assessed by exercise capacity, right heart catheterization at rest and after submaximal exercise, MRI, echocardiography, and Holter monitoring. When administered at a dose of 2 IU/d, rhGH doubled the serum concentration of insulin-like growth factor-I. rhGH improved clinical symptoms and exercise capacity significantly (New York Heart Association class 2.4+/-0.5 initially versus 1.4+/-0.5 at 3 months [mean+/-SD], P<0.05; VO2max 13.6+/-3.8 versus 17.4+/-5.4 mL. kg-1. min-1, P<0.05). Additionally, pulmonary capillary wedge pressures at rest and after submaximal exercise were reduced significantly. Cardiac output increased, particularly at rest (5.0+/-1.1 versus 5.8+/-1.3 L/min; P<0.05). Posterior wall thickness was increased (1.08+/-0.1 versus 1. 24+/-0.3 cm; P<0.05), and the end-diastolic and end-systolic volume indexes decreased significantly after rhGH treatment. There was no significant increase in left ventricular ejection fraction. The improvements were partially reversed 3 months after rhGH discontinuation. CONCLUSIONS: The administration of rhGH for 3 months in patients with ischemic cardiomyopathy results in significant improvement in hemodynamics and clinical function. The attenuation of left ventricular remodeling persisted 3 months after discontinuation of treatment.

Combined Modality Therapy↗

PubMed2005

Angiotensin-converting enzyme genotype is not associated with exercise capacity or the training effect of cardiac rehabilitation in patients after acute myocardial infarction.

BACKGROUND: The relationship of the genotype for the angiotensin-converting enzyme (ACE) with exercise capacity or training effects has been studied in athletes or healthy persons, but recently the ACE DD genotype was reported to be associated with decreased exercise capacity in patients with congestive heart failure. Therefore, in the present study the association between the ACE genotype and exercise capacity was investigated in patients with acute myocardial infarction (AMI) participating in cardiac rehabilitation (CR) for 3 months. METHODS AND RESULTS: The study population comprised 168 patients stratified as II (n=75), ID (n=67), and DD (n=26) according to ACE genotype. Baseline left ventricular ejection fraction (LVEF) was similar among the genotype groups. In all patients, exercise capacity (peak work rate (PWR) and peak oxygen uptake (PVO 2)) significantly increased after CR. However, no differences were observed in PWR and PVO2 among the genotype groups at baseline or after CR. The results were similar even when analyzed in 60 patients with left ventricular (LV) dysfunction (LVEF <45%). CONCLUSION: The present study suggests that there is no association between ACE I/D polymorphism and exercise capacity in patients after AMI, even with LV dysfunction. Furthermore, ACE genotype may have no influence on the effects of CR after AMI.

Exercise Test↗

PubMed2005

Tissue Doppler-derived indices predict exercise capacity in patients with apical hypertrophic cardiomyopathy.

BACKGROUND: Although impaired left ventricular (LV) diastolic function is a prominent feature of hypertrophic cardiomyopathy (HCM), diastolic function and its relation to exercise capacity in apical HCM (ApHCM) has not been explored previously. This study was sought to determine the relationship between diastolic mitral annular velocities combined with conventional Doppler indexes and exercise capacity in patients with ApHCM. PATIENTS: Twenty-nine patients with ApHCM (24 men; mean age +/- SD, 57 +/- 10 years) underwent supine bicycle exercise with simultaneous respiratory gas analysis and two-dimensional and Doppler echocardiographic study. RESULTS: The mitral inflow velocities (early filling [E], late filling, and deceleration time) were traced and measured. Early diastolic mitral annular velocity (E') was measured at the septal corner of mitral annulus by Doppler tissue imaging (DTI) from the apical four-chamber view. Pro-brain natriuretic peptide (proBNP) was measured at the time of echocardiography using a quantitative electrochemiluminescence immunoassay. E/E' ratio correlated inversely with maximal oxygen uptake (Vo(2)max) [r = - 0.47, p = 0.0106]. There was a significant positive correlation between E' and Vo(2)max (r = 0.41, p = 0.024). However, no correlation was found between conventional two-dimensional, Doppler indices, and proBNP and Vo(2)max). Of all the echocardiographic and clinical parameters assessed, E/E' ratio had the best correlation with exercise capacity (r - 0.47) and was the strongest independent predictor of Vo(2)max by multivariate analysis (p = 0.0106). CONCLUSIONS: DTI-derived indexes (E', E/E' ratio), an estimate of myocardial relaxation and LV filling pressures, correlate with exercise capacity in patients with ApHCM, suggesting that abnormal diastolic function may be a factor limiting exercise capacity.

Aged↗

PubMed2002

A mechanistic investigation of ACE inhibitor dose effects on aerobic exercise capacity in heart failure patients.

BACKGROUND: Angiotensin converting enzyme inhibitors at high doses have been shown to improve prognosis of heart failure patients. Their beneficial effects on exercise capacity have been less convincing in large parallel group studies. The objective of this investigation was to explore the mechanisms involved in dose-related functional effects and to test the hypothesis that a trial recommended high dose of lisinopril would improve aerobic exercise capacity and cardiovascular function more than with a low dose. METHODS: Twelve patients with symptomatic heart failure completed a randomized double-blind crossover trial of lisinopril 5 mg o.d. and 20 mg o.d. for 24 weeks, crossing over the doses at 12 weeks. The primary end-point was aerobic exercise capacity, and the secondary end-points were cardiac performance at peak exercise and dobutamine stimulation. RESULTS: The aerobic exercise capacity (primary end-point) was significantly higher during the 5mg per day dosage compared to the 20 mg (1696 vs 1578 ml.min(-1), P=0.016), equivalent to a rise of 1.53 ml.kg(-1)min(-1) from the 19.6 ml.kg(-1)min(-1) with 20mg when normalized by body weight. Seventy-three percent of patients showed greater peak oxygen consumption and peak cardiac power output with the 5mg per day dose than the 20 mg, and none showed the opposite. In terms of cardiac performance, although the results were not statistically significant, there was a consistent pattern showing the same directional changes in favour of the lower dose in peak exercise cardiac power output and cardiac power output at maximal dobutamine. There were no significant differences in the resting values. A total of 24 adverse reactions were reported during the 5 mg phase compared to 38 during the 20 mg phase. CONCLUSIONS: Contrary to expectation, the aerobic exercise capacity of patients was found to be greater with the lower dose of lisinopril, suggesting that therapy with ACE inhibitors for heart failure may require tailoring the doses to the individual to optimize functional benefits in relation to the assumed prognostic benefits.

Aged↗

PubMed1997

Pre- and postoperative exercise capacity associated with hemodynamics in adult patients with atrial septal defect: a retrospective study.

OBJECTIVE: This study evaluated the pre- and postoperative exercise capacity in adult patients with atrial septal defect (ASD) associated with hemodynamic variables. METHODS: Adults (70) with ASD underwent symptom-limited exercise tests. Peak O2 uptake (Peak VO2) and % peak VO2, that is the percentage of predicted value, were measured. These patients were divided into three groups according to pulmonary-to-systemic flow ratio (Qp/Qs) and systolic pulmonary arterial pressure (PAs); Group A: Qp/Qs < or = 3, PAs < or = 50 mm Hg, Group B: Qp/Qs > 3, any PAs, Group C: Qp/Qs < or = 3, PAs > 50 mm Hg. Exercise test was repeated in 22 patients after surgical closure of ASD (mean 4.6 +/- 2.0 months). RESULTS: Peak VO2 was significantly lower in group B (P < 0.01) and group C (P < 0.01) than in group A (19.3 +/- 5.7, 17.6 +/- 3.6, 27.6 +/- 6.3 ml/min/kg, respectively). In patients except those in group C, there were a weak negative correlation between PAs and % peak VO2 (r = 0.61) and a significant negative correlation between Qp/Qs and % peak VO2 (r = 0.86). Postoperative peak VO2 increased significantly in group A (27.2 +/- 5.1-31.1 +/- 5.1 ml/min/kg, P < 0.05) and group B (16.7 +/- 3.3-21.5 +/- 2.1 ml/min/kg, P < 0.01). However, there was no significant difference between pre- and postoperative peak VO2 in group C (16.8 +/- 1.3-17.8 +/- 2.8 ml/min/kg, NS). CONCLUSIONS: In ASD patients except those with small or moderate left-to-right shunt and high pulmonary arterial pressure, there was a significant negative correlation between Qp/Qs and peak VO2 corrected by age and gender. Patients with large left-to-right shunt and/or high pulmonary arterial pressure had reduced exercise capacity. However, exercise capacity in patients with large left-to-right shunt increased after closure of ASD regardless of whether they had high pulmonary arterial pressure.

Adult↗

PubMed1999

Contribution of lung function to exercise capacity in patients with chronic heart failure.

BACKGROUND: The importance of exercise capacity as an indicator of prognosis in patients with heart disease is well recognized. However, factors contributing to exercise limitation in such patients have not been fully characterized and in particular, the role of lung function in determining exercise capacity has not been extensively investigated. OBJECTIVE: To examine the extent to which pulmonary function and respiratory muscle strength indices predict exercise performance in patients with moderate to severe heart failure. METHODS: Fifty stable heart failure patients underwent a maximal symptom-limited cardiopulmonary exercise test on a treadmill to determine maximum oxygen consumption (VO2max), pulmonary function tests and maximum inspiratory (PImax) and expiratory (PEmax) pressure measurement. RESULTS: In univariate analysis, VO2max correlated with forced vital capacity (r = 0.35, p = 0.01), forced expiratory volume in 1 s (r = 0.45, p = 0.001), FEV1/FVC ratio (r = 0.37, p = 0.009), maximal midexpiratory flow rate (FEF25-75, r = 0. 47, p < 0.001), and PImax (r = 0.46, p = 0.001), but not with total lung capacity, diffusion capacity or PEmax. In stepwise linear regression analysis, FEF25-75 and PImax were shown to be independently related to VO2max, with a combined r and r2 value of 0. 56 and 0.32, respectively. CONCLUSIONS: Lung function indices overall accounted for only approximately 30% of the variance in maximum exercise capacity observed in heart failure patients. The mechanism(s) by which these variables could set exercise limitation in heart failure awaits further investigation.

Adult↗

PubMed2004

Improving exercise capacity, 6 wk training tends to reduce circulating endothelin after heart transplantation.

Short-term survival is no longer the pivotal issue after heart transplantation but, most heart-transplant (Htx) patients still present with increased circulating endothelin-1 (ET) and reduced exercise capacity. ET-1 limits both exercise-induced vasodilation and blood flow redistribution toward acting muscles and might be accessible to training. This study was performed to investigate the effect of training on ET-1 and whether an eventual training-induced improvement in exercise capacity may be related to reduced baseline or exercise circulating ET-1 in Htx patients. Five Htx patients performed a maximal bicycle exercise test and an endurance exercise test before and after a training program of 18 exercises sessions during 6 wk. ET-1 was determined by radioimmunoassay at rest, end endurance exercise and 30 min recovery, before and after training. Training improved significantly Htx's maximal oxygen uptake (+13.1 +/- 4.8%; p < 0.05) and also reduced significantly the endurance exercise-induced heart rate increase. Resting ET-1 was increased in Htx (5.98 +/- 1.88 vs. 1.61 +/- 0.25 pmol/L in controls; p < 0.01) but although ET-1 modulation might participate in training-induced beneficial effects, training failed to modulate either resting or exercise ET-1 plasma level. Training-induced improvement in exercise capacity might not mainly due to decreased ET-1 after heart transplantation. Further supporting the usefulness of training, these preliminary data suggest that improved exercise capacity may not be mainly due to decreased ET-1 in Htx patients. Further, larger scale studies will be needed to investigate whether an impaired nitric oxide pathway stimulation might explain such results and whether a longer training program can reduce local ET-1, arising from working muscles after heart transplantation.

Adult↗

PubMed1996

Breathlessness and exercise capacity in heart failure: the role of bronchial obstruction and responsiveness.

The cause of the breathlessness and reduced exercise capacity that occur in patients with chronic heart failure remains obscure. We examined the hypothesis that airway obstruction and bronchial hyper-responsiveness, which are recognised features of chronic heart failure, might contribute to the breathlessness and reduced exercise capacity in this condition. We studied 37 patients (7 female) with chronic heart failure, of mean age 61 years. Each patient underwent: (i) lung function testing with spirometry and expiratory flow volume loops. (ii) Measurement of bronchial responsiveness to methacholine. (iii) Symptom-limited treadmill exercise capacity using both incremental and fixed workload protocols, with measurement of Borg scores for breathlessness. Lung function was not significantly related to either exercise time, or Borg symptom scores in either exercise protocol. Bronchial hyper-responsiveness to methacholine was demonstrated in 12 patients. Exercise time did not correlate with the degree of bronchial hyper-responsiveness in these 12 patients. Group mean exercise time and Borg scores were not significantly different in these 12 patients when compared to the 25 patients in whom bronchial hyper-responsiveness was not found. We conclude that airway obstruction and bronchial hyper-responsiveness are not likely to be important determinants of reduced exercise capacity and breathlessness in chronic heart failure.

Airway Obstruction↗

PubMed1991

Cardiac function and exercise capacity of diabetic patients.

To evaluate the relationship between cardiac function at rest and the exercise capacity of diabetic patients, left ventricular function and exercise capacity were evaluated in 15 non-insulin-dependent male diabetic patients. Isovolumic relaxation time (IRT) and the PEP/LVET ratio were obtained by simultaneous echophonocardiograms, electrocardiograms, and recordings of the carotid arterial pulse. VO2 at anaerobic threshold was obtained from a cycle ergometer exercise test with expired gas analysis. Patients were divided into two groups: those with IRT less than 90 msec (Group 1) and those with IRT greater than or equal to 90 msec (Group 2). Group 2 patients had a lower VO2 at anaerobic threshold than Group 1 (Group 1: 17.4 +/- 3.6, Group 2: 12.9 +/- 2.5 ml/min/kg; M +/- SD, p less than 0.05). There was a good correlation between the IRT at rest and delta HR, defined as the change in heart rate from rest to anaerobic threshold (r = 0.666, p less than 0.01), and between delta HR and the beat-to-beat variation in R-R interval at rest (r = 0.637, p less than 0.02). There was also a good correlation between VO2 at anaerobic threshold and IRT (r = 0.555, p less than 0.05), and between VO2 at anaerobic threshold and delta HR (r = 0.858, p less than 0.01). Our data suggests that both left ventricular diastolic function and cardiac sympathetic nervous system reflexes, reflected by delta HR, may affect the exercise capacity of diabetic patients. Thus, IRT obtained by a non-invasive method may provide a useful index for cardiovascular response to exercise in diabetic patients without coronary artery disease.

Adult↗

PubMed1993

Reduction of mismatch of global ventilation and perfusion on exercise is related to exercise capacity in chronic heart failure.

BACKGROUND: The inability to match lung perfusion to ventilation because of a reduced cardiac output on exercise contributes to reduced exercise capacity in chronic heart failure. OBJECTIVE: To quantify ventilation to perfusion matching at rest and at peak exercise in patients with chronic heart failure and relate this to haemodynamic and ventilatory variables of exercise capacity. DESIGN: Eight men in New York Heart Association class II underwent maximal bicycle ergometry with expired gas analysis. MAIN OUTCOME MEASURES: On separate days, ventilation and perfusion gamma camera imaging was performed at rest, and at 80% of previous peak exercise heart rate during bicycle ergometry. The vertical distribution of mismatch between ventilation and perfusion (V/Q) was estimated from subtracted profiles of activity (ventilation and perfusion) to derive a numerical index of global mismatch. RESULTS: Maximal mean (SD) oxygen consumption on bicycle ergometry was 16.0 (4.5) ml min-1 kg-1. There was a reduction in the global V/Q mismatch index from 23.96 (5.90) to 14.88 (7.90) units (p < 0.01) at rest and at peak exercise. Global V/Q mismatch index at peak exercise correlated negatively with maximal minute ventilation (R = -0.90, p < 0.01) and with maximal mean arterial pressure (R = -0.79, p < 0.05), although no relation was seen with maximal oxygen consumption. The reduction in global V/Q mismatch index from rest to peak exercise correlated with maximal oxygen consumption (R = 0.88, p < 0.01), and with maximal minute ventilation (R = 0.87, p < 0.01). CONCLUSIONS: During exercise in patients with chronic heart failure, there is a reduction in the global V/Q mismatch index. A lower global V/Q mismatch index at peak exercise is associated with higher maximal ventilation. The reduction in global V/Q mismatch index on exercise correlates well with maximal exercise capacity. This may imply that the inability to perfuse adequately all regions of lung on exercise and match this to ventilation is a factor determining exercise capacity in chronic heart failure.

Aged↗

PubMed2005

Effect of fuels on exercise capacity in muscle phosphoglycerate mutase deficiency.

BACKGROUND: Muscle phosphoglycerate mutase deficiency (PGAMD) is a rare, recessively inherited metabolic myopathy that affects one of the last steps of glycolysis. Clinically, PGAMD resembles muscle phosphorylase deficiency (McArdle disease) and phosphofructokinase deficiency (PFKD). However, it is unknown whether PGAMD is associated with a second-wind phenomenon during exercise, as in McArdle disease, and whether patients with PGAMD, like patients with PFKD and McArdle disease, benefit from supplementation with fuels that bypass the metabolic block. OBJECTIVE: To investigate whether fuels that bypass the metabolic block can improve exercise capacity or whether exercise capacity improves during sustained exercise. DESIGN: Single-blind, placebo-controlled investigation of the effects of glucose, lactate, and intralipid on work capacity in patients with PGAMD. SETTING: National University Hospital, University of Copenhagen, and Neuromuscular Center, Institute for Exercise and Environmental Medicine. Patients Two unrelated men (21 and 26 years old) with PGAMD who since their teens had experienced muscle cramps, muscle pain, and episodes of myoglobinuria provoked by brief vigorous exercise, 4 patients with McArdle disease (mean +/- SD age, 32 +/- 5 years) with 0% residual phosphorylase activity in muscle, and 6 healthy, untrained male volunteers (mean +/- SD age, 23 +/- 1 years) were studied. INTERVENTIONS: Using constant and variable workload protocols on a cycle ergometer, it was investigated whether a spontaneous second wind occurs during exercise in patients with PGAMD, and using a constant workload protocol followed by an incremental load to exhaustion, it was tested whether infusion of lactate, glucose, or intralipid alters the exercise tolerance in PGAMD. MAIN OUTCOME MEASURES: Whether a second wind occurs during exercise and whether fuels that bypass the metabolic block can improve exercise and oxidative capacity. RESULTS: In contrast to patients with McArdle disease, with whom they share many clinical features, in patients with PGAMD, cycle exercise and oxidative capacity are virtually normal, a second wind does not occur, and lipid and lactate supplements do not improve exercise capacity. CONCLUSION: Although the clinical manifestations of PGAMD mimic McArdle disease with respect to the presence of exertional muscle cramps, rhabdomyolysis, and myoglobinuria, this study shows that cycle exercise responses are strikingly different.

Adult↗

PubMed2000

Impact of Doppler-derived left ventricular diastolic performance on exercise capacity in normal individuals.

BACKGROUND: Doppler-derived left ventricular (LV) diastolic indexes have been shown to correlate with exercise capacity in patients with heart diseases as well as healthy individuals. However, it is uncertain whether they predict exercise capacity independent of noncardiac factors. METHODS: To clarify the impact of the LV diastolic index on exercise capacity, 160 healthy individuals were investigated. All underwent Bruce protocol treadmill stress testing and 2-dimensional and Doppler echocardiography. Estimated metabolic equivalent was calculated from exercise time (metabolic equivalent = 1.11 + 0.016 x exercise time). Diastolic performance was assessed by Doppler transmitral flow velocity pattern. Pulmonary function tests and complete blood cell count were also performed. RESULTS: LV diastolic indexes correlated well with metabolic equivalent (peak transmitral filling velocity (A): r = -0.51, P <.0001; ratio of early and late transmitral filling velocities (E/A): r = 0.58, P <. 0001). However, there was no significant correlation between LV systolic indexes and metabolic equivalent. Independent predictors for a higher metabolic equivalent by multivariate analysis were higher E/A (P <.0001), higher vital capacity (P =.001), smaller body mass index (P =.0003), younger age (P =.0050), and higher hemoglobin concentration (P =.0026). CONCLUSION: Doppler-derived LV diastolic index may help in predicting exercise capacity in normal individuals independent of other cardiac and extracardiac factors.

Adult↗

PubMed2002

Does lung diffusion impairment affect exercise capacity in patients with heart failure?

OBJECTIVE: To determine whether there is a relation between impairment of lung diffusion and reduced exercise capacity in chronic heart failure. DESIGN: 40 patients with heart failure in stable clinical condition and 40 controls participated in the study. All subjects underwent standard pulmonary function tests plus measurements of resting lung diffusion (carbon monoxide transfer, TLCO), pulmonary capillary volume (VC), and membrane resistance (DM), and maximal cardiopulmonary exercise testing. In 20 patients and controls, the following investigations were also done: (1) resting and constant work rate TLCO; (2) maximal cardiopulmonary exercise testing with inspiratory O2 fractions of 0.21 and 0.16; and (3) rest and peak exercise blood gases. The other subjects underwent TLCO, DM, and VC measurements during constant work rate exercise. RESULTS: In normoxia, exercise induced reductions of haemoglobin O2 saturation never occurred. With hypoxia, peak exercise uptake (peak O2) decreased from (mean (SD)) 1285 (395) to 1081 (396) ml/min (p < 0.01) in patients, and from 1861 (563) to 1771 (457) ml/min (p < 0.05) in controls. Resting TLCO correlated with peak O2 in heart failure (normoxia < hypoxia). In heart failure patients and normal subjects, TLCO and peak O2 correlated with O2 arterial content at rest and during peak exercise in both normoxia and hypoxia. TLCO, VC, and DM increased during exercise. The increase in TLCO was greater in patients who had a smaller reduction of exercise capacity with hypoxia. Alveolar-arterial O2 gradient at peak correlated with exercise capacity in heart failure during normoxia and, to a greater extent, during hypoxia. CONCLUSIONS: Lung diffusion impairment is related to exercise capacity in heart failure.

Blood Gas Analysis↗

PubMed2004

Effects of cardiac rehabilitation on exercise capacity in Type 2 diabetic patients with coronary artery disease.

AIM: To determine whether Type 2 diabetic patients with coronary disease can obtain, after cardiac rehabilitation, a similar benefit on exercise capacity to non-diabetic coronary individuals. RESEARCH DESIGN AND METHODS: Fifty-nine Type 2 diabetic patients and 36 age-matched non-diabetic patients were enrolled in a 2-month cardiac rehabilitation programme, after an acute coronary event. At the beginning and at the end of the cardiac rehabilitation programme, each subject underwent a cardiopulmonary exercise test to assess exercise capacity as measured by peak workload, duration of test, maximal heart rate, peak VO2 and anaerobic threshold. The two groups of patients were not different in age, sex ratio, type of coronary event or left ventricular ejection fraction. RESULTS: The baseline exercise capacity parameters were not different between diabetic and non-diabetic subjects. After cardiac rehabilitation, improvement of exercise capacity was significantly less in patients with diabetes compared with those without diabetes: peak workload (19% vs. 29%, P = 0.022), peak VO2 (13% vs. 30%, P = 0.002), anaerobic threshold (12% vs. 31%, P = 0.017). In the diabetic patients, a significant inverse relation between fasting blood glucose and change in peak VO2 was observed on both univariate (r = -0.40, P = 0.002) and multivariate (P = 0.001) analyses. CONCLUSIONS: The benefit of cardiac rehabilitation, after an acute ischaemic heart event, in exercise capacity is significantly lower in Type 2 diabetic patients. The response to cardiac rehabilitation in those with diabetes appears to be influenced by blood glucose levels.

Cholesterol↗

PubMedDate not supplied

Relationship between different indices of exercise capacity and clinical measures in patients with chronic obstructive pulmonary disease.

PURPOSE: The purpose of this study was to make comparisons between different types of exercise tests used in chronic obstructive pulmonary disease (COPD) to better interpret the results and to select the most suitable testing procedure. Therefore, we evaluated the relationship between exercise capacity and other clinical measures and their relative contributions to exercise capacity in patients with COPD. METHOD: We studied 36 patients with stable COPD. All patients underwent baseline pulmonary function testing. Dyspnea during activities of daily living was assessed with the Oxygen Cost Diagram (OCD). The Hospital Anxiety and Depression Scale and the St George's Respiratory Questionnaire were used to assess psychologic status and health-related quality of life, respectively. All patients performed the 6-minute walking test, progressive cycle ergometry, and the cycle endurance test. RESULTS: Each exercise capacity result correlated significantly with pulmonary function, the OCD, and the Activity and Total scores of the St George's Respiratory Questionnaire. Multiple regression analyses revealed that the OCD was an important predictor of exercise capacity, especially for the walking test. Diffusing capacity was also a significant predictor on progressive cycle ergometry. Body mass index was the most significant predictor of the endurance time. CONCLUSION: The 3 different exercise tests had similar characteristics in relation to pulmonary function, dyspnea, and health-related quality of life in patients with COPD. However, some differences were found in the aspects they evaluated.

Aged↗

PubMed2006

Long-term neurodevelopmental outcome and exercise capacity after corrective surgery for tetralogy of Fallot or ventricular septal defect in infancy.

BACKGROUND: The purpose of this prospective study was to assess whether neurodevelopmental status and exercise capacity of children 5 to 10 years after corrective surgery for tetralogy of Fallot or ventricular septal defect in infancy was different compared with normal children and influenced by the preoperative condition of hypoxemia or cardiac insufficiency. METHODS: Forty unselected children, 20 with tetralogy of Fallot and hypoxemia and 20 with ventricular septal defect and cardiac insufficiency, operated on with combined deep hypothermic circulatory arrest and low flow cardiopulmonary bypass at a mean age of 0.7 +/- 0.3 years (mean +/- SD), underwent, at mean age 7.4 +/- 1.6 years, standardized evaluation of neurologic status, gross motor function, intelligence, academic achievement, language, and exercise capacity. Results were compared between the groups and related to preoperative, perioperative, and postoperative status and management. RESULTS: Rate of mild neurologic dysfunction was increased compared with normal children, but not different between the groups. Exercise capacity and socioeconomic status were not different compared with normal children and between the groups. Compared with the normal population, motor function, formal intelligence, academic achievement, and expressive and receptive language were significantly reduced (p < 0.01 to p < 0.001) in the whole group and in the subgroups, except for normal intelligence in ventricular septal defect patients. Motor dysfunction was significantly higher in the Fallot group compared with the ventricular septal defect group (p < 0.01) and correlated with neurologic dysfunction, lower intelligence, and reduced expressive language (p < 0.05 each). Reduced New York Heart Association functional class was correlated with lower exercise capacity and longer duration of cardiopulmonary bypass (p < 0.05 each). Reduced socioeconomic status significantly influenced dysfunction in formal intelligence (p < 0.01) and academic achievement (p < 0.05). Preoperative risk factors such as prenatal hypoxia, perinatal asphyxia, and preterm birth, factors of perioperative management such as cardiac arrest, lowest nasopharyngeal temperature, and age at surgery, and postoperative risk factors as postoperative cardiocirculatory insufficiency and duration of mechanical ventilation were not different between the groups and had no influence on outcome. Degree of hypoxemia in Fallot patients and degree of cardiac insufficiency in ventricular septal defect patients did not influence the outcome within the subgroups. CONCLUSIONS: Children with preoperative hypoxemia in infancy are at higher risk for motor dysfunction than children with cardiac insufficiency. Corrective surgery in infancy for tetralogy of Fallot or ventricular septal defect with combined circulatory arrest and low flow bypass is associated with reduced neurodevelopmental outcome, but not with reduced exercise capacity in childhood. In our experience, the general risk of long-term neurodevelopmental impairment is related to unfavorable effects of the global perioperative management. Socioeconomic status influences cognitive capabilities.

Child↗