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PubMed2005

Psychological outcomes of an outpatient pulmonary rehabilitation program in patients with chronic obstructive pulmonary disease.

STUDY/PRINCIPLES: The effects of an outpatient pulmonary rehabilitation program on psychological morbidity (anxiety and depressive symptoms) were examined in patients with chronic obstructive pulmonary disease (COPD). METHODS: The 26 rehabilitation patients with COPD were compared with 19 control patients with COPD similar in age, gender, COPD severity and other variables. Initial assessment included lung function testing, health status, exercise tolerance, dyspnea intensity and psychiatric interviews using Hamilton depression rating scale (HAM-D) and Hamilton anxiety rating scale (HAM-A). A pulmonary rehabilitation program was carried out during the following 2 months; psychiatric interviews and measurements of health status, exercise tolerance and dyspnea intensity were done again on completion of the study at 2 months. RESULTS: There was a decrease in HAM-A scores in the rehabilitation group and the decrease was statistically significant (P=0.010). On the contrary the HAM-A scores did not change in control group. The decrease in HAM-A scores in rehabilitation group was also statistically significant compared with the control group (P=0.042). There was no significant difference in HAM-D scores within the two groups and also there was no significant difference between the two groups in HAM-D scores. The health status, exercise tolerance and dyspnea intensity improved significantly in the rehabilitation group compared to the control group. CONCLUSION: This study shows that our outpatient rehabilitation program leads to a benefit in anxiety and depressive symptoms in COPD patients. The benefit was especially significant in anxiety symptoms. In addition to the improvement in psychological symptoms, the health status, exercise tolerance and dyspnea intensity were also significantly improved in COPD patients who underwent the rehabilitation program. This outpatient-based rehabilitation program was well accepted by the patients. The relatively simple design of the program makes it feasible independently of expensive equipment.

Aged↗

PubMed1995

[Effect of theophylline on disturbances of ventilation and of gas exchange during exercise in patients with pulmonary emphysema].

Factors limiting exercise were studied in 23 patients with pulmonary emphysema, and the effects of theophylline on exercise tolerance and on hypercapnic ventilatory response were studied in 16 patients with pulmonary emphysema. Exercise in these patients was limited by inability to increase tidal volume and by disturbances of gas exchange, as indicated by low PaO2, high AaDO2, and high PaCO2 during exercise, and by low diffusing capacity. Theophylline increased tidal volume during exercise, but it did not improve oxygenation during exercise. Theophylline improved exercise tolerance and hypercapnic ventilatory response. The percent increases in VEmax and in VO2max after theophylline administration correlated significantly with the percent increase in the ratio of mouth occlusion pressure to PACO2 during rebreathing. These results indicate that exercise tolerance in patients with pulmonary emphysema can be improved by theophylline, probably because of an increase in ventilatory drive.

Aged↗

PubMed1994

Quality of life in patients with chronic obstructive pulmonary disease improves after rehabilitation at home.

We have developed a rehabilitation programme at home and have investigated its effects on quality of life (QOL), lung function, and exercise tolerance in patients with chronic obstructive pulmonary disease (COPD). We studied 43 patients with severe airflow obstruction: forced expiratory volume in one second (FEV1) 1.3 +/- 0.4 l (mean +/- SD), FEV1/inspiratory vital capacity (IVC) 37 +/- 7.9%. After stratification, 28 patients were randomly allocated in a home rehabilitation programme for 12 weeks. Fifteen patients in a control group received no rehabilitation. The rehabilitation group received physiotherapy by the local physiotherapist, and supervision by a nurse and a general practitioner. Quality of life was assessed by the four dimensions of the Chronic Respiratory Questionnaire (CRQ). We found a highly significant improvement in the rehabilitation group compared to the control group for the dimensions dyspnoea, emotion, and mastery. Lung function showed no changes in the rehabilitation group. The exercise tolerance improved significantly in the rehabilitation group compared to the control group. The improvement in quality of life was not correlated with the improvement in exercise tolerance. Rehabilitation of COPD patients at home may improve quality of life; this improvement is not correlated with an improvement in lung function and exercise tolerance.

Breathing Exercises↗

PubMed1991

Acute and chronic antianginal efficacy of continuous twenty-four-hour application of transdermal nitroglycerin. Steering Committee, Transdermal Nitroglycerin Cooperative Study.

To resolve the controversies surrounding the antianginal use of chronic, continuous 24-hour transdermal nitroglycerin therapy, a double-blind, placebo-controlled, randomized, parallel-group study was designed. Eligible patients had chronic angina pectoris with symptom-limited, reproducible treadmill tests and were responsive to sublingual nitroglycerin (n = 562). Patients were randomly assigned to placebo or 1 of 7 doses of active treatment (15, 30, 45, 60, 75, 90 and 105 mg/24 hours). In the active drug groups, treatment was initiated with 15 mg/24 hours during the first week of double-blind dosing with subsequent weekly increases until the assigned dose was reached, after which the dose was held constant. Treadmill tests were performed 0, 4 and 24 hours after the initial double-blind patches were applied, after each titration step and after 8 weeks. At the end of double-blind therapy, a sublingual nitroglycerin exercise challenge was repeated. Exercise tolerance in patients using the active patch increased 34 seconds (p less than 0.05) over patients taking placebo 4 hours after the initial application of double-blind therapy, but there was no statistically significant difference in exercise time between placebo and active drug groups by 24 hours after the first application or for the remaining 8 weeks of the trial. Increasing the dose did not overcome the loss of effect. A partial attenuation of the response to a sublingual nitroglycerin challenge seen on exercise tolerance testing also occurred, with patients who received the highest dose showing the greatest attenuation. There were no differences in angina frequency among the groups, although in a post hoc analysis, patients with greater than 7 attacks per week had a reduction in anginal frequency of 6 to 7 attacks per week with active treatment versus 2 attacks per week with placebo. The study showed that (1) tolerance to the exercise effects of continuous transdermal nitroglycerin develops within 24 hours after application; and (2) increasing the dose does not overcome this tolerance. The observation that symptomatic improvement may occur in the absence of increases in exercise tolerance seems deserving of further study.

Administration, Cutaneous↗

PubMed1993

[Congenital isolated complete atrioventricular block: long-term experience with 38 patients].

BACKGROUND: The management of patients with isolated congenital complete heart block is controversial, and indications for cardiac pacing are not clearly defined. In the present study we report our long-term experience in the management of patients with this disease. METHODS: Thirty-eight consecutive patients aged 2 days to 28 years (mean age 10 years) were studied and followed up for 130 +/- 57 months (range 18 to 274). They underwent an extensive evaluation including history, physical examination, electrocardiography and echocardiography; thirty-seven patients had Holter monitoring and exercise test. Electrophysiologic study was performed in 24 patients. RESULTS: Twenty-two patients were asymptomatic, sixteen had symptoms as syncope or presyncope (7 patients), marked exercise intolerance (1 patient), presyncope and marked exercise intolerance (1 patient), heart failure (1 patient), mild dyspnea on exertion (6 patients). Electrocardiograms showed a narrow QRS in all patients. Holter monitoring showed a marked bradycardia (awake heart rate < or = 55 beats/min in infants, < or = 40 beats/min in children and adults) in 15 patients and junctional pauses of > 3 seconds in 9 of them. The exercise test showed a markedly reduced exercise tolerance in 2 patients and exercise-induced complex ventricular arrhythmias in 3 patients. Echocardiography showed a structurally normal heart and a normal left ventricular function in all patients. The electrophysiologic study always showed a suprahisian site of block. Twenty patients (53%) underwent cardiac pacing at a median age of 14 +/- 10 years and were followed up for 110 +/- 59 months (range 18 to 253) after pacing; prophylactic pacing was performed in 10 patients. Indications for cardiac pacing were: syncope or presyncope (7 patients), presyncope and marked exercise intolerance (1 patient), neonatal heart failure (1 patient), marked exercise intolerance (1 patient), neonatal marked bradycardia (2 patients), marked bradycardia with junctional pauses of > 3 seconds and/or complex ventricular arrhythmias (7 patients), complex ventricular arrhythmias (1 patient). No death occurred during the follow-up. In 9 of 20 patients who had cardiac pacing, indication for this procedure appeared during the follow-up (development of symptoms, marked bradycardia and/or complex ventricular arrhythmias). Complications of pacing were infrequent (9 complications in 7 patients) and mainly occurred in the first years of our experience. At present 12 patients have an atrioventricular sequential pacing and 8 have a rate-responsive ventricular one. All patients who had pacing showed an improvement of exercise tolerance; 11 of them underwent exercise test after pacing which showed a significant increase in exercise duration (from 11.1 +/- 1.9 to 15.3 +/- 1.1 min, p < 0.01). In the 3 patients with complex ventricular arrhythmias we observed their suppression after atrioventricular sequential pacing. At present 35 patients are asymptomatic and 3 have mild dyspnea on exertion. CONCLUSIONS: Our results confirm that patients with isolated congenital complete heart block often have symptoms and/or signs of electric instability without symptoms. Cardiac pacing relieves symptoms and improves working capacity. Although in this study we are not able to draw conclusions on the therapeutic value of prophylactic pacing, our favourable follow-up results suggest that this therapeutic approach may prevent complications.

Adolescent↗

PubMedDate not supplied

[The electrocardiogram during physical stress and Holter monitoring in the detection of asymptomatic myocardial infarct].

INTRODUCTION: In patients with myocardial infarction acute myocardial ischaemia could be manifested by characteristic ischaemic symptoms or noncharacteristic symptoms such as cardiac insufficiency or heart rhythm disturbances. Sometimes myocardial ischaemia is not followed by any symptom. This condition is known as asymptomatic myocardial ischaemia. Asymptomatic myocardial ischaemia usually could be detected by treadmill exercise tolerance test or 24-hour Holter ECG monitoring. PATIENTS AND METHODS: We analyzed a group of 58 patients suffering from myocardial infarction with ST segment depression during the treadmill exercise tolerance test. All patients were on Holter 24-hour ECG monitoring. As a criterion of myocardial ischaemia during Holter monitoring ST segment depression of 1 mm and more, lasting 1 minute and more, and 0.08" of J point was accepted. RESULTS: During the treadmill exercise tolerance test segment depression was not followed by any symptom in 18 (31%) patients. There were no differences in the number of patients with hypertension in the group with symptoms and the group without symptoms. Diabetes mellitus was more frequent in the group with asymptomatic myocardial ischaemia. The average values of maximum ST segment depression and heart rates during treadmill tests were not statistically significant in both groups (with and without symptoms). During daily activities myocardial ischaemia was found in 30 (51%) patients by a 24-hour Holter ECG monitoring. We observed 198 episodes of myocardial ischaemia of which 138 (69.1%) were asymtomatic. The amplitude of ST segment depression and duration of these changes were significantly greater in the group with symptomatic episodes than in the group with asymptomatic episodes of myocardial ischaemia. DISCUSSION: Asymptomatic myocardial ischaemia is an often appearance in patients with myocardial ischaemia. Almost in 25% of persons in whom sudden death occurred obstructive changes in coronary arteries during the autopsy were found. Asymptomatic myocardial ischaemia could be found even an a "completely healthy person" without any complaints. Asymptomatic myocardial ischaemia is usually detected in a "completely healthy person" by casual diagnosis, in patients with stable and non stable angina pectoris, in patients with stenosis of the coronary arteries proved by angiography, and in patients after myocardial infarction. Some authors considered that treadmill exercise tolerance testing is less reliable to discover asymptomatic myocardial ischaemia comparing to the continuous 24-hour Holter ECG monitoring. It is know that in patients with diabetes mellitus neuropathy precedes the onset of symptomatic myocardial ischaemia. Asymptomatic myocardial ischaemia has the same predictive value for prognosis of the disease as symptomatic myocardial ischaemia. In some patients "anginal alarm system" is defective, and perception and conduction of pain sensations are disturbed. CONCLUSION: 1. In 31% of patients who suffered from myocardial infarction with ST segment depression during the treadmill testing asymptomatic myocardial ischaemia was found. 2. By Holter monitoring ischaemia ST segment depression during the exertion is observed in 52% of patients. Most of ischaemic episodes were asymptomatic. 3. The amplitude of ST segment depression is significantly greater and duration of depression is significantly longer in symptomatic episodes of myocardial ischaemia comparing to asymptomatic myocardial ischaemia obtained by Holter ECG monitoring.

Electrocardiography↗

PubMed2006

Sitaxsentan for treatment of pulmonary hypertension.

OBJECTIVE: To review the literature pertinent to the efficacy and safety of sitaxsentan, a selective endothelin (ET)-A receptor antagonist under evaluation for the treatment of pulmonary arterial hypertension (PAH). DATA SOURCES: Articles were identified through searches of the MEDLINE (1966-November 2006) and International Pharmaceutical Abstracts (1970-November 2006) databases, using the key words endothelin antagonist, pulmonary arterial hypertension, pulmonary hypertension, sitaxsentan, and TBC11251. Searches were limited to articles published in English. STUDY SELECTION AND DATA EXTRACTION: Due to the limited number of articles on sitaxsentan, all studies captured in the search results were evaluated. DATA SYNTHESIS: Four studies of sitaxsentan in humans with PAH have been published to date. An uncontrolled open-label study and a randomized placebo-controlled study (STRIDE-1; Sitaxsentan to Relieve Impaired Exercise-1) showed sitaxsentan to improve exercise tolerance in patients with PAH, as evidenced by significant increases in the distance walked in 6 minutes. Significant hepatotoxicity developed in patients receiving sitaxsentan 300 mg. The benefits of sitaxsentan with respect to exercise tolerance and hemodynamics were sustained in a one year extension of the placebo-controlled study. The results of a multicenter, randomized, placebo-controlled trial of 2 doses of sitaxsentan with an open-label bosentan arm (STRIDE-2) suggested that only the 100 mg dose provided superior benefit in exercise tolerance and improvement in functional class. Treatment-related adverse effects were similar for all groups. CONCLUSIONS: Sitaxsentan appears to be superior to placebo in improving exercise tolerance in patients with PAH but may produce therapeutic outcomes similar to those of bosentan, a comparator agent. The optimal dose of sitaxsentan appears to be 100 mg once daily. Information about the use of sitaxsentan in a greater number of patients with PAH for longer periods is necessary to further define its place in the treatment of PAH.

Animals↗

PubMed2003

Mid-term results of combined transmyocardial laser revascularization and coronary artery bypass.

BACKGROUND: Transmyocardial laser revascularization is increasingly used to treat intractable angina in the absence of graftable vessels; however, its role in combination with coronary artery bypass grafting remains undefined. The aim of this pilot study was to investigate the outcome of the combination therapy at mid-term follow-up. METHODS: Patients (n = 20) who had elective coronary artery bypass with one or more nongraftable coronary arteries were prospectively randomized to have either coronary artery bypass grafting alone or combination coronary artery bypass grafting plus transmyocardial laser revascularization with a holmium:YAG (yttrium-aluminum-garnet) laser to nongraftable areas. All patients had an exercise tolerance test preoperatively and at 6, 18, and 36 months follow-up. Stress echocardiography was performed on 17 patients at 18 months postoperatively, and regional wall motion score index was calculated in lased and nonlased nonrevascularizable myocardium of the left ventricle at rest and with dobutamine stress. RESULTS: Both groups of patients were similar in preoperative demographics and operative data. There was no perioperative death. There was no difference between the two groups in angina scoring at 6, 18, and 36 months follow-up. Exercise tolerance improved by a mean of 46.8 +/- 20.0 seconds in the coronary artery bypass grafting group versus 199.2 +/- 66.5 seconds per patient in the coronary artery bypass grafting plus transmyocardial laser revascularization group (p = 1.8 x10(-6)) at 6 months; this benefit was maintained at 18 months (157 +/- 46.3 versus 61 +/- 39.2 seconds; p = 4 x10(-4)) but was lost at 36 months (57.2. +/- 42.1 versus 68.1 +/- 46.7 seconds; p = 0.70). The mean values for wall motion score index in the lased and nonlased regions at each stage of dobutamine stress at 18 months after surgery were not statistically significant. CONCLUSIONS: The combination of coronary artery bypass and transmyocardial laser revascularization improved exercise tolerance in patients in whom complete revascularization could not be achieved by bypass grafting alone in the short term, but this benefit was lost by 36 months postoperatively. The transient improvement in exercise tolerance cannot be explained by changes in contractility in the lased areas.

Aged↗

PubMed1996

An individualized protocol is more accurate than a standard protocol for assessing exercise capacity after heart transplantation.

BACKGROUND: Subjective improvement and normalization of exercise tolerance are reported by most of patients after heart transplantation. However, objective measurements often do not confirm the subjective improvement. This disparate observation may be related to the methods used to test exercise tolerance. We postulated that an individualized, more gradual exercise protocol might allow a more accurate assessment of exercise tolerance than standard protocols for patients with transplanted, denervated hearts. METHODS: Eleven stable heart recipients exercised on a treadmill using two different protocols. Protocol A was a standard Naughton's protocol, and protocol B was an individualized Naughton's protocol, in which the slope of the treadmill was increased only after a steady state in heart rate and oxygen consumption had been achieved and maintained for 30 seconds. RESULTS: Patients exercised longer and reached a higher workload with protocol B than with protocol A. Time to anaerobic threshold was significantly prolonged by protocol B. Minute ventilation and oxygen consumption at anaerobic threshold were significantly higher with protocol B than with protocol A. At peak exercise, heart rate, oxygen consumption, oxygen pulse, and minute ventilation were similar with the two protocols and exceeded 75% of the predicted corresponding maximal values for a normal matched population. CONCLUSIONS: The use of an individualized, gradual exercise protocol for heart transplant recipients detected a significantly better submaximal exercise capacity than a standard protocol, which is more consistent with the subjective improvement in functional capacity in this population.

Adult↗

PubMed2002

Pharmacological treatment of coronary artery disease with recombinant fibroblast growth factor-2: double-blind, randomized, controlled clinical trial.

BACKGROUND: Single-bolus intracoronary administration of fibroblast growth factor-2 (FGF2) improved symptoms and myocardial function in a phase I, open-label trial in patients with coronary artery disease. We conducted the FGF Initiating RevaScularization Trial (FIRST) to evaluate further the efficacy and safety of recombinant FGF2 (rFGF2). METHODS AND RESULTS: FIRST is a multicenter, randomized, double-blind, placebo-controlled trial of a single intracoronary infusion of rFGF2 at 0, 0.3, 3, or 30 microg/kg (n=337 patients). Efficacy was evaluated at 90 and 180 days by exercise tolerance test, myocardial nuclear perfusion imaging, Seattle Angina Questionnaire, and Short-Form 36 questionnaire. Exercise tolerance was increased at 90 days in all groups and was not significantly different between placebo and FGF-treated groups. rFGF2 reduced angina symptoms as measured by the angina frequency score of the Seattle Angina Questionnaire (overall P=0.035) and the physical component summary scale of the Short-Form 36 (pairwise P=0.033, all FGF groups versus placebo). These differences were more pronounced in highly symptomatic patients (baseline angina frequency score < or =40 or Canadian Cardiovascular Society score of III or IV). None of the differences were significant at 180 days because of continued improvement in the placebo group. Adverse events were similar across all groups, except for hypotension, which occurred with higher frequency in the 30-microg/kg rFGF2 group. CONCLUSIONS: A single intracoronary infusion of rFGF2 does not improve exercise tolerance or myocardial perfusion but does show trends toward symptomatic improvement at 90 (but not 180) days.

Adult↗

PubMed1988

Impaired myocardial perfusion in patients with hypertrophic cardiomyopathy: assessment with digital subtraction coronary arteriography.

To study the clinical significance of abnormal myocardial perfusion in patients with hypertrophic cardiomyopathy (HCM), we performed a computerized washout analysis of digital subtraction coronary arteriograms in 28 patients with HCM and 16 control subjects. The contrast disappearance half-life (T1/2) was calculated from a time-density curve generated in the four sectors of the myocardium perfused by the left anterior descending coronary artery and the mean T1/2 was calculated by averaging T1/2 values for these four sectors. Patients with HCM demonstrated longer T1/2 in the ventricular septal region than control subjects. Thirteen (46%) of the patients with HCM presented abnormally longer mean T1/2 values, suggesting impaired myocardial perfusion. Family histories of HCM were more frequent in patients with abnormal mean T1/2 values (92% vs 47%; p less than 0.05). On the exercise stress test, patients with abnormal T1/2 values presented significantly lower exercise tolerance with more frequent exercise-induced ST segment depression (62% vs 13%; p less than 0.05). However, there were no significant differences between the two groups with regard to ventricular wall thickness, left ventricular end-diastolic pressure, or the severity of systolic narrowing of the coronary arteries. These findings suggest that 13 (46%) of the patients with HCM have impaired myocardial perfusion, which may be a manifestation of intramural coronary artery disease in addition to left ventricular hypertrophy, elevated left ventricular end-diastolic pressure, or systolic narrowing of the coronary arteries. Additionally, significant association of the prolonged T1/2 with a familial occurrence of HCM and depressed exercise tolerance with ST segment depression imply that impaired myocardial perfusion could be an important inherent pathophysiological state leading to myocardial ischemia during exercise.

Adolescent↗

PubMed1988

Enhancing sexual performance in COPD.

The fear of dyspnea and reduced exercise tolerance in patients with chronic obstructive pulmonary disease (COPD) are often limiting factors in their participation in sexual activity. When the patient and health care practitioner approach sexual activity as any other physical activity, factors can be identified that promote sexual performance. Initial evaluation includes the patient's preferences, priorities and current physical capacity. The phases of sexual intercourse can be correlated with the energy requirements of other activities, such as walking or household tasks, to determine an individual's activity tolerance. Energy conservation techniques and breathing retraining can then be coordinated with sexual activity. In addition, cardiopulmonary reconditioning exercises are initiated to increase overall activity tolerance. Throughout this process, education is critical to assure the patient that well-tolerated exercise may include dyspnea, and that dyspnea during sex is not more dangerous than during other well-tolerated exercise.

Dyspnea↗

PubMed2005

How to assess physical activity? How to assess physical fitness?

Regular aerobic physical activity (PA) increases exercise capacity and physical fitness (PF), which can lead to many health benefits. Accurate quantification of PA and PF becomes essential in terms of health outcome and effectiveness of intervention programmes. In this manuscript we present a review regarding the assessment of physical activity and fitness. Three types of PA assessment methods can be distinguished: criterion methods, objective methods and subjective methods. Criterion methods like doubly labelled water, indirect calorimetry and direct observation are the most reliable and valid measurements against which all other PA assessments methods should be validated, but they also hold important drawbacks. Objective PA assessment methods include activity monitors (pedometers and accelerometers) and heart rate monitoring. Finally, questionnaires and activity diaries are considered subjective methods. For the assessment of PF, we distinguish field tests and laboratory tests. The Eurofit for Adults is a test battery that is designed to assess health-related fitness of individuals, communities, sub-populations and populations. It is mainly used for evaluating the morphological component, the muscular component, the motor component and the cardio-respiratory component. In the laboratory, exercise capacity is preferentially assessed through maximal incremental exercise testing. Cardio-pulmonary exercise testing is a well-established procedure that provides a wealth of clinically diagnostic and prognostic information. The peak oxygen uptake is the gold standard in the assessment of exercise tolerance. When maximal exercise is contraindicated or not achievable, the VAT or the submaximal slopes provide reasonable alternatives.

Adult↗

PubMed2001

Stress-induced blood pressure reactivity and incident stroke in middle-aged men.

BACKGROUND AND PURPOSE: Exaggerated blood pressure reactivity to stress is associated with atherosclerosis and hypertension, which are known stroke risk factors, but its relation to stroke is unknown. Previous work also indicates that the association between reactivity and cardiovascular diseases may be influenced by socioeconomic status. METHODS: The impact of blood pressure reactivity and socioeconomic status on incident stroke was examined in 2303 men (mean age, 52.8+/-5.1 years) from a population-based, longitudinal study of risk factors for ischemic heart disease in eastern FINLAND: Reactivity was calculated as the difference between blood pressure measured during the anticipatory phase of an exercise tolerance test (before exercise) and resting blood pressure, measured 1 week earlier. Mean systolic reactivity was 20 mm Hg (+/-15.9), and mean diastolic reactivity was 8.6 mm Hg (+/-8.5). Socioeconomic status was assessed as years of education. One hundred thirteen incident strokes (90 ischemic) occurred in 11.2 (+/-1.6) years of follow-up. RESULTS: Men with exaggerated systolic reactivity (>/=20 mm Hg) had 72% greater risk of any stroke (relative hazard ratio [RH], 1.72; 95% CI, 1.17 to 2.54) and 87% greater risk of ischemic stroke (RH, 1.87; 95% CI, 1.20 to 2.89) relative to less reactive men. Moreover, men who were high reactors and poorly educated were nearly 3 times more likely to suffer a stroke than better educated, less reactive men (RH, 2.90; 95% CI, 1.66 to 5.08). Adjustment for stroke risk factors had little impact on these associations. Diastolic reactivity was unrelated to stroke risk. CONCLUSIONS: Excessive sympathetic reactivity to stress may be etiologically important in stroke, especially ischemic strokes, and low socioeconomic status confers added risk.

Adult↗

PubMed2000

Influence of valve replacement on plasma endothelin-1 level in mitral stenosis.

BACKGROUND AND AIM OF THE STUDY: The rise of pressure in the pulmonary circulation during the course of mitral stenosis leads to pathomorphological changes and a reduction in vascular compliance. Endothelial dysfunction is also promoted, with increased expression of endothelin. This aim of this study was to evaluate whether the increase in endothelin-1 levels in pulmonary hypertension due to advanced mitral stenosis is reversible after valve replacement. METHODS: Thirty-nine patients with isolated, longlasting post-rheumatic mitral stenosis were enrolled. During preoperative Swan-Ganz catheterization blood samples were withdrawn from the pulmonary artery and capillaries for measurement of endothelin-1 (ET-1). Similar examinations were performed six months after mitral valve replacement. Hemodynamic parameters were measured also during 25-W exercise effort. RESULTS: The mean preoperative hemodynamic parameters of the pulmonary circulation were moderately increased. Mean plasma levels of ET-1 were about three-fold higher than normal. Capillary levels of ET-1 were significantly higher than those in the pulmonary artery (1.78+/-1.22 versus 1.03+/-1.16 pg/ml, p <0.05). There was no significant correlation between ET-1 level and any hemodynamic or clinical parameters, except NYHA functional class. After surgery, pulmonary capillary levels of ET-1 fell significantly, but were still high (1.78+/-1.22 versus 1.41+/-1.00 pg/ml); ET-1 levels in the pulmonary artery were unchanged. Patients with persistently high ET-1 levels had significantly worse exercise hemodynamic parameters, especially of pulmonary arterial compliance. CONCLUSION: In patients with long-lasting, severe mitral stenosis, ET-1 levels remained increased and the ET-1 concentration gradient across the pulmonary circulation persisted for six months after valve replacement. High ET-1 capillary levels are correlated with poor exercise tolerance and poor exercise compliance of the pulmonary vessels.

Endothelin-1↗

PubMed1995

[Effect of supplemental oxygen on exercise performance in patients with chronic obstructive pulmonary disease and an arterial oxygen tension over 60 Torr].

The effects of supplemental oxygen on exercise tolerance and exercise-induced dyspnea in patients with chronic obstructive pulmonary disease (COPD) and an arterial oxygen tension (PaO2) over 60 Torr were studied. Twenty two men who met the criteria stated above underwent three 6-minute walk tests while breathing room air, compressed air, or supplemental oxygen, in a double-blind randomized crossover fashion. The distance walked in 6 minutes was recorded, and the degree of dyspnea during exercise was quantified on a visual analog scale with a questionnaire that had eight descriptors of dyspnea sensations. The distances walked were: 535 +/- 27 (SE) for room air, 545 +/- 27 for compressed air, and 563 +/- 23 m for O2. These data indicate a significant placebo effect and an effect of supplemental oxygen. The data regarding dyspnea also indicated both a significant placebo effect and an effect of supplemental oxygen, but the descriptors for the placebo effect differed from those for the effect of supplemental oxygen. Patients in whom arterial desaturation (below 88%) developed during exercise with compressed air benefited from supplemental oxygen: they walked significantly farther and their dyspnea scores for two of the eight descriptors were significantly lower. However, patients in whom arterial desaturation (below 88%) did not develop during exercise with compressed air did not benefit from supplemental oxygen. Nonetheless, the degree of dyspnea during exercise with compressed air could not be used to predict the beneficial effect of supplemental oxygen.

Aged↗

PubMedDate not supplied

[Effectiveness of long-term ACE-inhibition on pulmonary diffusion and ventilation-perfusion ratio in chronic heart failure: correlation with physical performance].

Pulmonary dysfunction contributes to exercise intolerance in patients with chronic heart failure, and ACE-inhibition improves the functional capacity of these subjects. In this study, we investigated whether and how ACE-inhibitors affect pulmonary function and ventilatory response during exercise in chronic heart failure. Twenty patients with idiopathic dilated cardiomyopathy and left ventricular ejection fraction < 35% underwent pulmonary function tests and exercise evaluation with analysis of expired gases before and after 1 year of treatment with enalapril (10 mg bid). To explore whether or not the respiratory influence of ACE-inhibitors is peculiar to the syndrome of cardiac failure, we also studied 19 subjects with mild, untreated primary hypertension who followed the same protocol. In this group, enalapril exerted a neutral effect on pulmonary function. In chronic heart failure patients, lung volumes were abnormal and did not improve after enalapril treatment; on the contrary, alveolar diffusing capacity for carbon monoxide increased towards normal values. Exercise tolerance time, peak exercise oxygen consumption, ventilation, and tidal volume also improved and the dead space to tidal volume ratio was reduced at the peak exercise and intermediate exercise phases (20, 60 W). Changes in carbon monoxide diffusion were positively correlated to those occurring during peak exercise oxygen consumption. A negative correlation was found between the variations in oxygen consumption and those in dead space to tidal volume ratio at peak exercise. We conclude that in patients with chronic heart failure, ACE-inhibition restores diffusing lung properties and improves ventilation-perfusion matching during exercise. In this syndrome, sustained reduction in gas exchange resistance is a fundamental therapeutic property of this class of drugs.

Adult↗

PubMed1999

Cardiopulmonary exercise testing in patients with 21mm St. Jude Medical aortic prosthesis.

BACKGROUND AND AIM OF THE STUDY: Small-sized prostheses may be associated with high transprosthetic gradients, particularly in patients with a body surface area (BSA) >1.70m2, affecting left ventricular mass regression, symptom improvement and long-term survival. However, the influence of such gradients on exercise tolerance has not been clearly defined. The study aim was to verify the utility of cardiopulmonary exercise testing (CPX) in detecting patient-prosthesis mismatch, and to identify the clinical and echocardiographic data that predict exercise tolerance at CPX in patients with a 21mm St. Jude Medical (SJM) aortic prosthesis. METHODS: Twenty patients (one male, 19 females; mean age 66 +/- 9 years) with a 21 mm SJM prosthesis were evaluated by means of 2D echocardiography and CPX at 36 +/- 10 months after operation. Patients were divided into groups on the basis of a BSA of <1.70 m2 (group 1, n = 12) or > or =1.70 m2 (group 2, n = 8). RESULTS: At echocardiography, left ventricular mass reduction was 16 +/- 10% versus 9 +/- 6% in groups 1 and 2, respectively, mean gradient (MG) was 15 +/- 6 versus 17 +/- 4 mmHg (p = NS), effective orifice area index (EOAi) 0.86 +/- 0.10 versus 0.79 +/- 0.09 cm2/m2 (p = 0.05). At CPX, group 2 patients showed a significantly lower exercise duration (p = 0.02), maximum workload (p = 0.02), peak O2 uptake (p = 0.01), anaerobic threshold (AT) (p = 0.03), ventilatory equivalent for CO2 at AT (p = 0.007), and O2 cost of work (p = 0.03). Group 1 patients showed a ventilatory origin for their effort dyspnea, while group 2 patients showed a significant circulatory component. At multivariate analysis, BSA, age, EOAi and MG were independent predictors of CPX results. CONCLUSIONS: In patients with a 21 mm aortic SJM prosthesis and a BSA > or =1.70m2, CPX allows detection of patient-prosthesis mismatch, in terms of impaired exercise tolerance due to circulatory causes. CPX results can be anticipated on the basis of the patient's BSA, age, EOAi and MG. In these patients, technical solutions allowing implantation of a larger prosthesis should be considered whenever an active lifestyle is anticipated after aortic valve replacement.

Aged↗