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61.
62.
Cardiorespiratory responses to exercise training after orthotopic cardiac transplantation 总被引:12,自引:0,他引:12
We have tested the feasibility and effectiveness of a 2 year (average 16 +/- 7 months) walk/jog exercise program on 36 male orthotopic cardiac transplant patients (21 to 57 years old) seen initially 2 to 23 months after surgery. Comparison of initial exercise test results with those in 45 age-matched normal men showed the patients to have a lesser lean body mass (56 +/- 7 vs 63 +/- 8 kg, p less than .001), with a higher resting heart rate (104 +/- 12 vs 77 +/- 14 beats/min, p less than .001) and systolic (138 +/- 16 vs 129 +/- 17 mm Hg, p less than .001) and diastolic (95 +/- 14 vs 84 +/- 10 mm Hg, p less than .001) blood pressures. Peak power output was less than normal (101 +/- 27 vs 219 +/- 41 W, p less than .001), as was peak heart rate (136 +/- 15 vs 176 +/- 13 beats/min, p less than .001), peak oxygen intake (VO2max) (22 +/- 5 vs 34 +/- 6 ml.kg.min-1, p less than .001), and absolute anaerobic threshold (1.18 +/- 0.40 vs 2.04 +/- 0.40 liters.min-1, p less than .001). Peak ventilatory equivalent was higher (48 +/- 9 vs 37 +/- 61.1-1, p less than .001). Cardiac output (Q), as estimated by the CO2 rebreathing method, was slightly above normal at rest (p less than .01), but below normal at two submaximal work rates. The group's average weekly training distance was 24 km, with eight highly compliant patients progressing to 32 km or more weekly. After training, lean tissue increased (+2.4 +/- 3.1 kg, p less than .001), and resting values were reduced for heart rate (-4 +/- 11 beats/min, p less than .05), systolic (-13 +/- 20 mm Hg, p less than .001), and diastolic (-9 +/- 17 mm Hg, p less than .001) blood pressures. There were significant reductions in submaximal values for minute ventilation (VE), ratings of perceived exertion, and diastolic blood pressure at equivalent workloads. Peak values increased for power output (+49 +/- 34 W, p less than .001), VO2max (+4.0 +/- 6.0 ml.kg.min-1, p less than .001), VE (+20 +/- 20 l.min-1, p less than .001), and heart rate (+13 +/- 17 beats/min, p less than .001), and decreased for diastolic blood pressure (-8 +/- 15 mm Hg, p less than .001).(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
63.
Massimiliano Cadamuro Simone Brivio Joachim Mertens Marta Vismara Anja Moncsek Chiara Milani Christian Fingas Maria Cristina Malerba Giorgia Nardo Luigi DallOlmo Eleonora Milani Valeria Mariotti Tommaso Stecca Marco Massani Carlo Spirli Romina Fiorotto Stefano Indraccolo Mario Strazzabosco Luca Fabris 《Journal of hepatology》2019,70(4):700-709
64.
65.
Peak oxygen intake and cardiac mortality in women referred for cardiac rehabilitation 总被引:3,自引:0,他引:3
Kavanagh T Mertens DJ Hamm LF Beyene J Kennedy J Corey P Shephard RJ 《Journal of the American College of Cardiology》2003,42(12):2139-2143
OBJECTIVES: This study investigated the prognostic importance of measured peak oxygen intake (VO(2peak)) in women with known coronary heart disease referred for outpatient cardiac rehabilitation. BACKGROUND: Exercise capacity is a powerful predictor of prognosis in men with known or suspected coronary disease. Similar findings are described in women, but fewer studies have utilized measured VO(2peak), the most accurate measure of exercise capacity. METHODS: A single-center design took data from 2,380 women, age 59.7 +/- 9.5 years (1,052 myocardial infarctions, 620 coronary bypass procedures, and 708 with proven ischemic heart disease), who underwent cardiorespiratory exercise testing. They were followed for an average of 6.1 +/- 5 years (median 4.5 years, range 0.4 to 25 years) until cardiac and all-cause death. RESULTS: We recorded 95 cardiac deaths and 209 all-cause deaths. Measured VO(2peak) was an independent predictor of risk, values > or =13 ml/kg/min (3.7 multiples of resting metabolic rate) conferring a 50% reduction in cardiac mortality (hazard ratio [HR] 0.5, p = 0.001). Considered as a continuous variable, a 1 ml/kg/min advantage in initial VO(2peak) was associated with a 10% lower cardiac mortality. Adverse predictors were diabetes (HR 2.73, p = 0.0005) and antiarrhythmic therapy (HR 3.93, p = 0.0001). CONCLUSIONS: As in men, measured VO(2peak) is a strong independent predictor of cardiac mortality in women referred for cardiac rehabilitation. 相似文献
66.
Magura S Horgan CM Mertens JR Shepard DS 《Alcoholism, clinical and experimental research》2002,26(3):416-422
The article represents the proceedings of a symposium at the 2001 RSA Meeting in Montreal, Canada. The organizer/chair was Stephen Magura. The presentations examined: (1) How managed care organization policies may affect enrollees' use of alcohol and other drug (AOD) treatment, by Constance Horgan and associates; (2) The determinants of patients' access to and utilization of AOD treatment in a large health maintenance organization, by Jennifer R. Mertens and Constance Weisner; (3) The impact on treatment access and costs of a statewide carve-out for AOD treatment for Medicaid, by Donald Shepard and associates; and (4) The predictive validity of a new patient assessment technology developed, in part, to better justify AOD treatment in response to the demands of managed care, by Stephen Magura and associates. 相似文献
67.
68.
HELICS: a European project to standardise the surveillance of hospital acquired infection, 1994-1995
Mertens R Van Den Berg JM Fabry J Jepsen OB 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》1996,1(4):28-30
During the 1990s several European countries began to set up national or regional networks for the surveillance of hospital acquired infections. Most of these networks were based on the US Centers for Disease Control and Prevention (CDC) National Nosocomia 相似文献
69.
Oxygen uptake versus exercise intensity: a new concept in assessing cardiovascular exercise function in patients with congenital heart disease
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Reybrouck T Mertens L Brusselle S Weymans M Eyskens B Defoor J Gewillig M 《Heart (British Cardiac Society)》2000,84(1):46-52
OBJECTIVE—To assess the relation between exercise intensity and oxygen uptake during graded exercise in paediatric patients who underwent surgical repair of congenital heart disease, and to compare it with conventional measures of aerobic exercise function.
DESIGN—Cross sectional study. Exercise testing was performed on a treadmill and gas exchange was measured on a breath by breath basis.
PATIENTS—29 patients who underwent an atrial switch operation for transposition of the great arteries (TGA) (mean (SD) age at testing 10.3 (2.5) years) and 30 patients who underwent total repair of tetralogy of Fallot (TF) (age 12.1 (3.3) years) performed graded exercise testing. Exercise responses were compared with data obtained in 24 normal controls (age 11.4 (2.6) years).
RESULTS—The slope of oxygen uptake versus exercise intensity averaged 1.50 (0.64) ml O2/min2/kg in the patients with TGA and 1.68 (0.75) ml O2/min2/kg after TF repair, both lower (p < 0.005) than in normal controls (2.42 (0.68) ml O2/min2/kg). The lower slope of oxygen uptake was correlated with a subnormal value for ventilatory anaerobic threshold, which averaged 78.0 (13.3)% of normal in TGA and 85.1 (10.6)% in TF. This was associated with a steeper slope (p = 0.001) of carbon dioxide output versus oxygen uptake above the ventilatory anaerobic threshold in TGA (1.26 (0.20)) and TF (1.20 (0.18)) compared with the normal controls (1.05 (0.13)), and also a steeper slope of ventilation versus carbon dioxide in TGA (47.0 (15.4)) and TF (41.5 (13.7)) than in the controls (30.3 (8.5)).
CONCLUSIONS—Calculation of the steepness of the slope of oxygen uptake versus exercise intensity is a valid measurement of oxygen flow to the exercising tissues, which may be limited in congenital heart disease.
Keywords: congenital heart disease; exercise testing; oxygen uptake; oxygen uptake kinetics 相似文献
DESIGN—Cross sectional study. Exercise testing was performed on a treadmill and gas exchange was measured on a breath by breath basis.
PATIENTS—29 patients who underwent an atrial switch operation for transposition of the great arteries (TGA) (mean (SD) age at testing 10.3 (2.5) years) and 30 patients who underwent total repair of tetralogy of Fallot (TF) (age 12.1 (3.3) years) performed graded exercise testing. Exercise responses were compared with data obtained in 24 normal controls (age 11.4 (2.6) years).
RESULTS—The slope of oxygen uptake versus exercise intensity averaged 1.50 (0.64) ml O2/min2/kg in the patients with TGA and 1.68 (0.75) ml O2/min2/kg after TF repair, both lower (p < 0.005) than in normal controls (2.42 (0.68) ml O2/min2/kg). The lower slope of oxygen uptake was correlated with a subnormal value for ventilatory anaerobic threshold, which averaged 78.0 (13.3)% of normal in TGA and 85.1 (10.6)% in TF. This was associated with a steeper slope (p = 0.001) of carbon dioxide output versus oxygen uptake above the ventilatory anaerobic threshold in TGA (1.26 (0.20)) and TF (1.20 (0.18)) compared with the normal controls (1.05 (0.13)), and also a steeper slope of ventilation versus carbon dioxide in TGA (47.0 (15.4)) and TF (41.5 (13.7)) than in the controls (30.3 (8.5)).
CONCLUSIONS—Calculation of the steepness of the slope of oxygen uptake versus exercise intensity is a valid measurement of oxygen flow to the exercising tissues, which may be limited in congenital heart disease.
Keywords: congenital heart disease; exercise testing; oxygen uptake; oxygen uptake kinetics 相似文献
70.
E K Verbeken M Cauberghs I Mertens J Clement J M Lauweryns K P Van de Woestijne 《Chest》1992,101(3):793-799
As part of a study of the structural-functional correlations of excised human lungs obtained at autopsy, the parenchyma and peripheral airways were examined by means of morphometric techniques. Among the 30 lungs characterized by the absence of fibrosis, ten differed from the normal and emphysematous lungs by a homogeneous dilatation of the airspaces, in excess of the dimensions predicted on the basis of age. Study of the standard deviations of the mean linear intercepts showed that the airspace dilatation was more regular than in emphysematous lungs; in addition, there was no clear-cut destruction, as estimated from the number of alveolar attachments. These lungs were characterized in addition by an increased thickening of alveolar septa, without inflammation or fibrosis, normal size of the diameter, and reduced density of the membranous bronchioles. Since these lungs were from people older than 60 years, it is assumed that they represent cases of exaggerated airspace enlargement of the aging lung, differing from emphysema by the absence of destruction of alveolar walls. The term "senile lung" is proposed or this condition. 相似文献