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At least 19 recordsLinked to original sources
PubMed2005

Exercise tolerance, exercise hyperpnea and central chemosensitivity to carbon dioxide in sleep apnea syndrome in heart failure patients.

BACKGROUND: Sleep apnea syndrome (SAS) and exercise hyperpnea are common in patients with chronic heart failure (CHF), and although it is not known whether they are both regulated by the same mechanisms, the hypothesis of the present study was that they are related to augmented central chemosensitivity. METHODS AND RESULTS: The oxygen desaturation index (ODI) was evaluated in 29 patients and those with ODI > 5 times/h underwent polysomnography. Patients with an apnea-hypopnea index (AHI) > 15 /h without evidence of obstructive apnea were defined as central SAS (CSAS). Cardiopulmonary exercise testing was performed to determine peak oxygen uptake and the VE-VCO2 slope. A hypercapnic gas mixture (7% CO2/93% O2) was used to activate the central chemoreflex. Nine patients had central SAS (CHF-CSAS) and 20 did not have apnea (CHF-nonSAS). Patients with CHF-CSAS had a lower peak oxygen uptake than the CHF-nonSAS group (13.0+/-2.4 vs 16.9+/-4.3 ml x kg(-1) x min(-1), p < 0.05). There was a significant correlation between central chemosensitivity and the AHI (r = 0.63, p < 0.05), between central chemosensitivity and the VE - VCO2 slope (r = 0.50, p < 0.01), whereas the VE-VCO2 slope showed an insignificant tendency to correlate with AHI (r = 0.44, p = 0.07). Conclusion CHF-CSAS is associated with impaired exercise tolerance and elevated central chemosensitivity is the responsible mechanism for CSAS and exercise hyperpnea.

Aged↗
PubMed2003

Effects of oral magnesium therapy on exercise tolerance, exercise-induced chest pain, and quality of life in patients with coronary artery disease.

Previous studies have demonstrated that magnesium supplementation improves endothelial function in patients with coronary artery disease (CAD). However, the impact on clinical outcomes, such as exercise-induced chest pain, exercise tolerance, and quality of life, has not been established. In a multicenter, multinational, prospective, randomized, double-blind and placebo-controlled trial, 187 patients with CAD (151 men, 36 women; mean +/- SD age 63 +/- 10 years, range 42 to 83) were randomized to receive either oral magnesium 15 mmol twice daily (Magnosolv-Granulat, total magnesium 365 mg provided as magnesium citrate) (n = 94) or placebo (n = 93) for 6 months. Symptom-limited exercise testing (Bruce protocol) and responses given on quality-of-life questionnaires were the outcomes measured. Magnesium therapy significantly increased intracellular magnesium levels ([Mg]i) in a substudy of 106 patients at 6 months compared with placebo (35.5 +/- 3.7 vs 32.6 +/- 2.9 mEq/L, p = 0.0151). Magnesium treatment significantly increased exercise duration time compared with placebo (8.7 +/- 2.1 vs 7.8 +/- 2.9 minutes, p = 0.0075), and lessened exercise-induced chest pain (8% vs 21%, p = 0.0237). Quality-of-life parameters significantly improved in the magnesium group. These findings suggest that oral magnesium supplementation in patients with CAD for 6 months results in a significant improvement in exercise tolerance, exercise-induced chest pain, and quality of life, suggesting a potential mechanism whereby magnesium could beneficially alter outcomes in patients with CAD.

Administration, Oral↗
PubMed2001

Enhanced external counterpulsation improves exercise tolerance, reduces exercise-induced myocardial ischemia and improves left ventricular diastolic filling in patients with coronary artery disease.

OBJECTIVES: We examined whether enhanced external counterpulsation (EECP) improves myocardial ischemia, exercise tolerance and cardiac function in patients with coronary artery disease (CAD). BACKGROUND: Enhanced external counterpulsation reduces angina and improves exercise tolerance in patients with CAD. Some objective improvements of ischemia by EECP have been reported, but they should be confirmed further. Detailed hemodynamic effects of EECP have been less well documented. METHODS: Enhanced external counterpulsation was performed for a total of 35 h in patients with stable CAD (n = 12) who showed evidence of exercise-induced myocardial ischemia despite conventional medical or surgical therapies. All patients had significant stenotic lesions in major coronary arteries. RESULTS: Enhanced external counterpulsation improved all exercise test parameters (p < 0.05): exercise duration, time to 1-mm ST segment depression, rate-pressure product at peak exercise and rate-pressure product at 1-mm ST segment depression. Moreover, the prevalence of exercise-induced reversible perfusion defects by thallium scintigraphy decreased after treatment (p < 0.01). Enhanced external counterpulsation did not alter systolic function but improved diastolic filling, left ventricular (LV) end-diastolic pressure (p < 0.05) by cardiac catheterization and LV peak filling rate end-diastolic volume/s (p < 0.01) and time to peak filling rate (p < 0.05) by radionuclide scintigraphy. These hemodynamic improvements were associated with decreased plasma brain natriuretic peptides levels after EECP (p < 0.05). CONCLUSIONS: Thus, EECP treatment improves exercise tolerance and reduced myocardial ischemia by thallium scintigraphy in association with improved LV diastolic filling in patients with stable CAD.

Aged↗
PubMed1987

Comparison of the effects of two doses of bisoprolol on exercise tolerance in exercise-induced stable angina pectoris.

Recently, bisoprolol has been investigated regarding its effects on exercise tolerance and the duration of action in patients with coronary heart disease (CHD) following single oral administration. It appears, however, that the extent of effects of 5 mg bisoprolol is not fully established yet. Therefore, the effects of 5 and 10 mg bisoprolol and the duration of action were assessed in 12 patients (10 male, 2 female; mean age 60.2 years) with stable angina pectoris due to CHD after repeated administration. Patients were given 5 or 10 mg bisoprolol once daily for 2 weeks according to a double-blind, randomized cross-over design. At entry one exercise tolerance test (ETT) served as baseline measurement and following each treatment period ETTs were performed before (24-hour value) and 3 hours after tablet intake. Exercise capacity (in W X min) was calculated until the onset of angina, 0.1 mV ST-segment depression and at peak exercise. Compared to baseline all workload values during active therapy were significantly improved (P less than or equal to 0.05) except for the workload till onset of angina with bisoprolol 5 mg at 24 hours. The effects at 3 hours were significantly stronger than those after 24 hours for both dosages. Significantly stronger effects were observed 3 hours as well as 24 hours after intake during treatment with 10 mg compared to 5 mg: at peak exercise on heart rate (P less than or equal to 0.05) and exercise capacity (P less than or equal to 0.01), at identical workload on heart rate (P less than or equal to 0.01) and rate-pressure product (P less than or equal to 0.01). It was found that bisoprolol 5 mg once daily leads to therapeutic effects with a clearly maintained duration of action over 24 hours, but further increase of peak exercise capacity may be achieved with 10 mg.

Administration, Oral↗
PubMed1999

Improvement in exercise tolerance and symptoms of congestive heart failure during treatment with candesartan cilexetil. Symptom, Tolerability, Response to Exercise Trial of Candesartan Cilexetil in Heart Failure (STRETCH) Investigators.

BACKGROUND: The renin-angiotensin system plays an important part in the pathogenesis of congestive heart failure (CHF). This study evaluated the effect of an angiotensin II type 1 receptor antagonist on exercise tolerance and symptoms of CHF. METHODS AND RESULTS: In this multicenter, double-blind, parallel-group study, 844 patients with CHF were randomized to 12 weeks' treatment with placebo (n=211) or candesartan cilexetil 4 mg (n=208), 8 mg (n=212), or 16 mg (n=213) after a 4-week placebo run-in period. Changes in exercise time, Dyspnea Fatigue Index score, NYHA functional class, and cardiothoracic ratio were determined. Candesartan cilexetil produced a dose-related improvement in exercise time. For the intention-to-treat population, the increase produced by candesartan cilexetil 16 mg was significantly greater than that produced by placebo (47.2 versus 30.8 seconds, P=0.0463). All doses of candesartan cilexetil significantly improved the Dyspnea Fatigue Index score relative to placebo. NYHA class improved more frequently in the candesartan cilexetil groups; the differences relative to placebo were not significant. The decrease in cardiothoracic ratio with candesartan 4 to 16 mg was small but statistically significant compared with placebo (all P<0.05). In all candesartan cilexetil groups, plasma renin activity and angiotensin II levels increased from baseline and aldosterone levels decreased in the 8- and 16-mg treatment groups. Candesartan cilexetil was well tolerated at all doses. CONCLUSIONS: In summary, treatment with candesartan cilexetil demonstrated significant improvements in exercise tolerance, cardiothoracic ratio, and symptoms and signs of CHF and was well tolerated.

Adult↗
PubMed2001

[Chronic obstructive pulmonary disease: evaluation of exercise tolerance using three different exercise tests].

The clinical usefulness of simple exercise tests in patients with chronic obstructive pulmonary disease (COPD) continues to give rise to debate. Questions remain about whether these tests assess maximum effort or only exercise tolerance (submaximal effort). To determine the levels of stress reached during the six-minute walking (6MW) test and stair climbing (SC) test and their relation to maximum aerobic capacity, 50 patients with COPD (FEV1 49 +/- 19%) were studied. Data collected included spirometric variables and VO2, heart rate (HR), ventilatory response and dyspnea during the progressive effort ergometric cycle (PEEC) test. Two 6MW and SC tests were completed on two separate days, with distance, number of steps, HR and dyspnea recorded. HR was higher during the PEEC test. Among the simple tests, SC caused a faster HR than did the 6MW test. Likewise, a significant linear relation was observed between VO2/kgpeak during the 6MW test (r2 = 0.27; p < 0.05) and the SC test (r2 = 0.33; p < 0.01). We therefore conclude that exercise tolerance in patients with COPD can be evaluated using simple stress tests. The SC test is probably the best simple way to determine maximum functional capacity, whereas the 6MW test can be reserved for measurement of exercise tolerance.

Aged↗
PubMed2002

[Relation between pulmonary ventilation parameters, exercise tolerance and quality of life in patients with chronic obstructive lung disease].

Patients with chronic obstructive pulmonary disease (COPD) do usually have decreased tolerance of exercise capacity and impaired quality of life. Several studies have shown that exercise capacity is related relatively weakly to lung functions in this group of patients. The aim of the present study was to find parameter which could better reflect or predict maximal exercise capacity. 19 patients with the diagnosis COPD with mean value of forced expiratory volume in one second (FEV1) 46% predicted (range 21-79%) entering pulmonary rehabilitation program were included into the study. Enrolled patients were chosen to cover the whole range of airway obstruction severity. Post-bronchodilator static and dynamic ventilation parameters were used for evaluation and calculation. Quality of live was measured using St. George's respiratory questionnaire (SGRQ), evaluating symptoms, activity and impact of the disease with range from 0 (the best level) to 100 (the worst level). Values of FEV1 (p < 0.001) and ratio of FEV1 to vital capacity (FEV1/VC, p < 0.001) were significantly positively correlated with 6 minute walking distance (6MWD). FEV1/VC were closely related to 6MWD then FEV1. The degree of hyperinflation expressed by residual volume (RV, p < 0.005) and by ratio of residual volume to total lung capacity (RV/TLC, p < 0.001) significantly negatively correlated with 6MWD. Maximal occlusion mouth pressures (PImax, p < 0.05) were positively related to 6MWD. Total score of SGRQ correlated significantly to maximal exercise capacity. Pulmonary function tests and respiratory muscle function have important impact on exercise tolerance in patients with COPD. Tolerance of exercise capacity is significantly reflected by total score of quality of life in this group of patients.

Aged↗
PubMed1994

Cardiopulmonary exercise testing in the evaluation of patients with ventilatory vs circulatory causes of reduced exercise tolerance.

INTRODUCTION: Cardiopulmonary exercise testing (CPX) is considered a useful procedure in the evaluation of circulatory, ventilatory, or mixed origin of reduced exercise tolerance. Our study was designed to compare CPX and a standard clinical-instrumental approach in the evaluation of patients with cardiopulmonary disorders. METHODS: Fifty-seven patients (31 male, 26 female; mean [+/- SE] age, 60 +/- 2 years) were studied. Each patient was evaluated by two different observers: one used standard clinical criteria, the other used gas exchange indexes, monitored during a maximal incremental CPX, performed on a cycle ergometer. Cardiac output (CO), at rest and at submaximal work level, was also obtained. RESULTS: In 46 patients (80.7 percent), a concordant evaluation was reached by the two observers (24 were found to have a predominant ventilatory disorder, 22 to have a circulatory disorder); among these, in subjects considered to have circulatory impairment, the maximal CO/maximal workload ratio was significantly lower than in the ventilatory group; in those with ventilatory impairment, the reduced exercise tolerance correlated with the resting spirometric values. In the remaining 11 patients (19.3 percent), CPX better defined the underlying pathophysiology of exercise limitation: in 10 of them, clinically classified as having a mixed or predominantly ventilatory disorder, a greater importance of the circulatory component was detected; 4 had evidence of pulmonary vascular impairment (high VE/VCO2 at anaerobic threshold). CONCLUSIONS: Our study confirmed the sensitivity of CPX in the evaluation of a reduced exercise tolerance in dyspneic patients with cardiopulmonary conditions; when compared with a clinical-laboratory approach, in some patients it allowed the detection of an underestimated circulatory component causing exercise limitation.

Aged↗
PubMed1989

Exercise tolerance and cardiorespiratory response to exercise before and after the Fontan operation.

To determine the effect of the Fontan operation on exercise tolerance and cardiorespiratory response to exercise, we compared the preoperative and postoperative responses to graded exercise to maximal effort in 20 patients who underwent a modified Fontan procedure. The mean interval between preoperative and postoperative exercise testing was 1.8 years. Postoperatively, total work performed, duration of exercise, and maximal oxygen uptake were significantly increased. Although cardiac output increased during exercise, the response was subnormal, and stroke volume was unchanged. The heart rate and systolic blood pressure during maximal exercise were not significantly changed from preoperative values, but the diastolic blood pressures during rest and maximal exercise were significantly increased postoperatively. Systemic arterial blood oxygen saturation increased after the modified Fontan operation, but during exercise, a mild but significant desaturation occurred (93% compared with 90%). The ventilatory equivalent for oxygen decreased toward normal during exercise. The respiratory rate and oxygen consumption during resting remained unchanged from preoperative values. For this subset of patients, these data indicate that exercise tolerance improves, cardiac output and stroke volume responses to exercise are subnormal, and ventilatory response to exercise decreases toward normal after the modified Fontan operation.

Adolescent↗
PubMed1986

Exercise tolerance and cardiorespiratory response to exercise after the Fontan operation for tricuspid atresia or functional single ventricle.

To determine the impact of the Fontan operation on exercise tolerance and on the cardiorespiratory response to exercise, we compared the results of graded exercise to maximal effort of 81 patients with tricuspid atresia or single functional ventricle studied preoperatively with those of 29 patients studied postoperatively. Postoperatively, the values for total work performed, duration of exercise and maximal oxygen uptake increased significantly. Regardless of operative status, the maximal heart rate during exercise was reduced. The cardiac output and stroke volume response to exercise were subnormal after operation. Systemic arterial blood oxygen saturation was reduced markedly preoperatively both at rest and during exercise; postoperatively, it was significantly greater than the preoperative value but it remained slightly abnormal. The ventilatory response to exercise (respiratory rate, minute ventilation and ventilatory equivalent for oxygen) decreased toward normal after operation. Exercise tolerance and the cardiorespiratory responses to exercise improve after the Fontan operation. Formal exercise testing is essential to quantitate the degree of improvement.

Adolescent↗
PubMed1999

[Role of right-to-left atrial shunt in exercise tolerance of patients with Ebstein anomaly].

The aim of this study was to assess cardiorespiratory tolerance to exercise in children with non-operated, paucisymptomatic and untreated froms of Ebstein's anomaly. The authors undertook a prospective study in 11 children, mean age 9.6 years, who had lung function tests, cardiorespiratory exercise stress tests (bicycle ergometry N = 8, treadmill N = 3) and contrast echocardiography. All parameters of spirometry were normal. Contrast echocardiography showed a right-to-left interatrial shunt in 7 children (group 1) whereas the remaining 4 children had no shunt (group 2). The resting oxygen saturation was 97.4 +/- 2%, with no difference between the two groups. On the other hand, oxygen saturation at peak VO2 (VO2 max) was 90 +/- 9.5%, significantly lower in group 1 than in group 2 (85.7 +/- 2.2% vs 98.2 +/- 1.2%; p = 0.03). In group 1, the VO2 max was correlated to oxygen saturation (r = 0.98; p < 0.001, N = 6). The oxygen desaturation was correlated with presence of a right-to-left interatrial shunt (p = 0.01). The reduced exercise tolerance of non-operated, paucisymptomatic children with Ebstein's anomaly is due to a right-to-left interatrial shunt. In patients with poor exercise tolerance, contrast echocardiography is advised for the detection of these atrial shunts.

Adolescent↗
PubMed2001

Validation of a specific activity questionnaire to estimate exercise tolerance in patients referred for exercise testing.

BACKGROUND: Physical activity and symptom questionnaires have been used as surrogates for exercise testing to estimate a patient's functional capacity and to individualize an exercise testing protocol in accordance with exercise testing guidelines. To validate these approaches, they must be compared with measured oxygen uptake (peak VO (2)). METHODS: Before exercise testing was performed, a brief, self-administered questionnaire (Veterans Specific Activity Questionnaire [VSAQ]) was given to 337 patients referred for exercise testing for clinical reasons. The VSAQ was used to estimate exercise tolerance on the basis of symptoms during daily activities to individualize ramp rates on the treadmill so that the test duration would be approximately 10 minutes. Clinical and demographic variables were added to the VSAQ responses in a stepwise regression model to determine their ability to predict both directly measured peak VO (2) and peak metabolic equivalents (METs) predicted from the treadmill workload. RESULTS: The mean exercise time was 9.6 +/- 3 minutes. Responses to the VSAQ and age were the strongest predictors of both measured and predicted exercise capacity. Small but significant contributions to the explanation of variance in both measured and estimated METs were made by resting heart rate, forced expiratory volume in 1 second expressed as a percentage of normal, exercise capacity predicted for age, and body mass index. The multiple R values from the regression equations for measured and estimated METs were 0.58 and 0.72, respectively. CONCLUSIONS: Estimating a patient's symptoms associated with daily activities along with age are the strongest predictors of a patient's exercise tolerance. The VSAQ, combined with pretest clinical data, predicts the estimated MET value from treadmill speed and grade better than directly measured METs do. When used for estimating a patient's symptom limits to individualize ramp rates on a treadmill, this approach yields an appropriate test duration in accordance with recent exercise testing guidelines.

Activities of Daily Living↗
PubMed1994

Relationship between exercise tolerance, hemodynamics at rest and during exercise and ejection fraction, and their prognostic relevance in asymptomatic postinfarction patients.

In 309 postmyocardial infarction patients (age 40 +/- 7.7 years) without persistent ischemia there is only a weak correlation between ejection fraction (EF) and exercise tolerance (r = 0.45, p < 0.01), and between EF and maximum cardiac output (CO; r = 0.41, p < 0.01) and maximum pulmonary capillary wedge pressure (PCWP; r = -0.32, p < 0.001). The same was true for exercise tolerance and maximum PCWP (r = -0.53, p < 0.001). A big scattering of individual values could be observed. Although we found a high positive correlation between maximum CO and exercise tolerance (r = 0.80, p < 0.001), in individual cases a low CO could be related to high exercise tolerance and vice versa. In the multivariate analysis, only the heart volume/kg body weight and maximum PCWP could be shown to be of independent prognostic importance for survival and/or mortality in the following years (chi 2 = 5.9, p < 0.015 and chi 2 = 7.2, p < 0.007, respectively).

Adult↗
PubMed1997

Effects of high-dose ipratropium bromide and oral aminophylline on spirometry and exercise tolerance in COPD.

Exercise tolerance in chronic obstructive pulmonary disease (COPD) patients treated with oral aminophylline may be different from those treated with high-dose inhaled ipratropium bromide. The purpose of this study was to compare the effects of therapeutic doses of oral aminophylline with high-dose ipratropium bromide on spirometry and exercise tolerance. The study was conducted on three consecutive days in a double-blind, randomized, crossover fashion. Baseline studies obtained on each study day included vital signs, simple spirometry and a symptom-limited maximal cardiopulmonary stress test, after which patients received one of the following treatments on each day: Treatment 1, inhaled ipratropium (total dose of 144 micrograms) with placebo tablets; Treatment 2, inhaled placebo with oral aminophylline (400 mg); Treatment 3, inhaled placebo and placebo tablets. Simple spirometry was repeated at 60 and 120 min after baseline. Vital signs and cardiopulmonary stress testing was repeated at 120 min. Eighteen patients were enrolled in the study, and 17 of these completed the study. There was a significant (P < 0.05) increase in both forced expiratory volume in 1 s (FEV1), from 0.75 (0.21) to 0.92 (0.3), and forced vital capacity (FVC), from 1.8 (0.79) to 2.11 (0.84), with high-dose ipratropium despite prior beta-agonist therapy. Lack of improvement in exercise capacity was noted with ipratropium despite improvement in spirometry. These results suggest that elderly patients with severe COPD may have exercise limitation that is not directly dependent on severity of airflow obstruction. Ipratropium bromide and aminophylline demonstrated no acute effects on exercise capacity.

Administration, Oral↗
PubMed2005

Significant ventilatory functional restriction in adolescents with mild or moderate scoliosis during maximal exercise tolerance test.

STUDY DESIGN: A prospective evaluation of cardiopulmonary tolerance to maximal exercise in adolescent idiopathic scoliosis. OBJECTIVES: To evaluate ventilatory functional restrictions during a maximal exercise tolerance test in idiopathic scoliosis patients with mild and moderate curves and to compare them with the results obtained in healthy adolescents matched in age undergoing similar test. SUMMARY OF BACKGROUND DATA: Adolescents with idiopathic scoliosis with mild curves do not exhibit significant restrictions in ventilatory parameters measured by conventional static spirometry. Few reports have dealt with cardiorespiratory response to maximal exercise in adolescent idiopathic scoliosis with mild to moderate curves. Although results seem to show a reduced exercise tolerance in these patients, the frequency and signification of the restricted work capacity is uncertain because of important design limitations in previous studies. METHODS: Thirty-seven girls diagnosed with adolescent idiopathic scoliosis with a mean age of 13 years (range, 11-16) and an average scoliotic curve of 32.8 degrees Cobb (range, 20-45 degrees) were studied by basal spirometry and dynamic ventilatory parameters during a maximal exercise tolerance test. Similar studies were performed in a control group of 10 healthy girls matched in age. Exercise test consisted of a ramp protocol on treadmill starting at a speed of 0.75 m/second (2.7 km/hour) with increments of 0.2 m/second (0.72 km/hour) per minute. All subjects completed the test to exhaustion to determine maximal oxygen uptake (VO2 max) and ventilatory efficiency parameters. RESULTS: There were no differences between scoliotic and healthy girls in basal ventilatory parameters (FVC, FEV1). However, adolescents with idiopathic scoliosis showed worse tolerance to exercise test with lower maximal speed average (9.4 km/hour versus 11.5 km/hour, P < 0.005), lower ventilatory efficiency at maximal exercise (VE: 68.9 L/minute versus 82.3 L/minute, P < 0.01), early anaerobic threshold, and a lower aerobic power expressed by 23% decreased body weight normalized VO2 max (38.6 mL/kg/minute versus 49.0 mL/kg/minute, P < 0.001). VEmax values were correlated to the severity of the scoliotic curve. Patients with more severe curves had greater limitation of ventilatory capacity (r = -0.374, P < 0.05). Maximal breath frequency was higher in scoliotic girls (54 versus 47, P < 0.05) suggesting a compensatory mechanism adopted in response to the lower ventilatory capacity during demanding exercise. When ventilatory efficiency was considered by the VE/VO2 ratio, scoliotic girls disclosed higher values than control (average 35.2 versus 29.6, P < 0.001) indicating an inefficiency in their ventilation. Patients wearing a brace at the time of ventilatory functional assessment did not exhibit any difference in the parameters investigated both at basal spirometry and during exercise tolerance test. CONCLUSION: Although patients with mild or moderate scoliosis do not exhibit cardiopulmonary restrictions in basal static conditions, they do show a significant lower tolerance to maximal exercise. Respiratory inefficiency together with lower ventilation capacity and lower VO2 max may be responsible for reduced exercise tolerance in adolescents with idiopathic scoliosis. Exercise deconditioning in scoliotic patients cannot be attributed to brace treatment.

Adolescent↗
PubMed1998

[The impact of 2-year rehabilitation on exercise tolerance and transcutaneous oxygen saturation during exercise in patients with chronic obstructive pulmonary disease].

We compared results of symptom-limited exercise test (ET) and percutaneous oxygen saturation (SaO2) during ET in rehabilitated COPD patients (R) and in control COPD patients (C) before and after 2 years of study. Group of R consisted of 27 patients (FVC 2.15 l, FEV1 1.17 l, mean age 58, range 32-76 years) who underwent comprehensive, in-hospital and domestic R, group C consisted of 19 patients (FVC 1.95 l, FEV1 1.42 l, mean age 68, range 55-83 years). The studied groups did not differ in their FVC and FEV1, but R patients were younger (p = 0.05), had more sustained ET (p = 0.0002) and greater number of METs achieved during ET (p = 0.0008). After study we found increased number of METs during ET from 3.94 to 4.77, p = 0.003, improved 10 grade Borg score in 3' ET from 4.0 to 2.5, p = 0.05 and tendency to decrease maximal drop of SaO2 during ET from 6.8 to 3.1% (NS). Patients in C group failed to improve results of ET: from 2.7 to 2.5 METs (NS), and pulse oximetry: maximal drop in SaO2 during ET from 3.1 to 3.07%, NS) and also 10-grade Borg score in 3'ET (from 2.0 to 2.8, NS). In conclusion, although differences in age and in initial exercise tolerance between studied groups could influence the results of this study, it seems that long term rehabilitation can improve both exercise tolerance and oxygen saturation during exercise in COPD patients.

Adult↗
PubMed2000

Worsening of left ventricular diastolic dysfunction during exercise causes decreased exercise tolerance in hypertension.

BACKGROUND: Exercise tolerance is reduced in hypertension. Hypertension affects left ventricular (LV) diastolic filling by causing abnormal relaxation and decreasing compliance. HYPOTHESIS: This study was designed to determine whether worsening of LV diastolic dysfunction during exercise causes decreased exercise tolerance in hypertension. METHODS: Left ventricular diastolic filling parameters were examined at mitral valve by Doppler echocardiography at rest and at peak exercise in hypertensive patients and were compared with those of age- and gender-matched normotensive individuals. Treadmill exercise stress test was performed according to the Bruce protocol and the exercise time was recorded. RESULTS: Exercise time was significantly shorter in the hypertensive group than that in the normotensive group (320 +/- 29 vs. 446 +/- 38 s, p 0.03). The hypertensive group demonstrated abnormal relaxation pattern of diastolic mitral inflow at rest, which became pseudonormal at peak exercise (E/A velocity ratio, rest 0.86 +/- 0.06 vs. exercise 1.19 +/- 0.09, p < 0.001). The diastolic mitral inflow pattern remained normal at peak exercise in the normotensive group. The deceleration time and the pressure half time of early mitral inflow at peak exercise were significantly shorter in the hypertensive group than those in the normotensive group (deceleration time, 182 +/- 20 vs. 238 +/- 22 ms, p 0.02: pressure half time, 54 +/- 5 vs. 70 +/- 12 ms, p 0.01). CONCLUSIONS: This study demonstrates that reduced exercise tolerance in hypertension is associated with worsening of diastolic dysfunction during exercise consistent with an increase in left atrial pressure.

Compliance↗