摘要:

It is generally agreed that ventilatory impairment is the primary abnormality responsible for exercise limitation in patients with chronic obstructive pulmonary disease (COPD). However, there is not a close relationship between the degree of ventilatory impairment and the exercise tolerance of these patients. Many patients with COPD have a decreased right ventricular ejection fraction (RVEF), either at rest or during exercise, and some have suggested that therapeutic measures should be directed at improving the RVEF. The purpose of this study was to determine the relationship between the exercise tolerance, as reflected by the maximum oxygen consumption (&OV0312;o2max), and the RVEF in patients with COPD when the degree of ventilatory impairment was taken into consideration. Pulmonary function testing, incremental upright cycle ergometer exercise tests to a symptom-limited maximum, and equilibrium-gated radionuclide RVEF at rest and at approximately 75% of the maximum workload were performed on 37 patients. The mean ± SD of the values obtained from the 37 patients were as follows: Age = 60 ± 6 yrs; o2max= 1100 ± 320 ml/min; FEV1 = 1490 ± 590 ml; rest RVEF = 38 ± 13%; exercise RVEF = 41 ± 13%. Data were analyzed using regression analysis with the &OV0312;o2maxas the dependent variable. The &OV0312;o2maxwas significantly correlated with the FEV1 (r = 0.53, P < 0.01), the FVC (r = 0.54, P < 0.01), and the FEV1/FVC (r = 0.57, P < 0.01). The &OV0312;o2maxwas not significantly correlated with the rest RVEF (r = −0.03), the exercise RVEF (r = 0.16) or the change in the RVEF from rest to exercise (r = 0.24). When multiple regression analysis was performed, the addition of the RVEF to the analysis did not significantly increase the correlation coefficients. In addition, the &OV0312;o2maxdid not differ significantly between groups of patients with or without right ventricular dysfunction either at rest (1.16 vs 1.05 L/min) or during exercise (1.15 vs 1.08 L/min). From this study, we conclude that although many patients with COPD have right ventricular dysfunction manifested by a low RVEF at rest or less than a 5% increase from rest to exercise, there is no significant correlation between this RV dysfunction and exercise tolerance.

ISSN:0883-9212    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Cost/benefit analysis suggests that exercise can be an economically effective measure in both secondary and tertiary cardiac rehabilitation. The direct and indirect costs of cardiac disease are enormous; exercise is a safe, effective, and pleasant treatment, with moderate costs relative to some alternative forms of therapy. Specific costs of exercise depend on the scale of facilities and the level of supervision that is proposed, but with most programs a substantial factor is foregone opportunity. The estimated economic benefit varies with the values chosen for discount rate, exercise compliance, and therapeutic impact, together with the type of allowance that is made for any increase in quality-adjusted survival. Estimates of the benefit from a reduction of premature death range from $5.63 to $90 per worker-year in secondary prevention, and from $10 to $120 per worker-year in tertiary prevention. In the symptom-free adult, the economic impact of an exercise program is probably much larger in terms of an immediate improvement of perceived health; this lessens the demand for medical services by up to $450 per worker-year, and also greatly improves industrial performance (lesser absenteeism, improved productivity, lower turnover rates, total impact about $500 per worker-year). If account is taken of these additional factors, there is ample economic justification for both secondary and tertiary rehabilitation programs.

ISSN:0883-9212    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

The purpose of this study was to evaluate a stationary cycle ergometer that was designed for controlling the heart rate (HR) of cardiac patients during an exercise training program. The cycle has the capability of maintaining a prescribed training HR (±5 beats/min) by adjusting power output. Twenty healthy subjects (44 ± 7 years) and 25 cardiac patients (59 ± 8 years) volunteered as participants. The patients had documented myocardial infarction, coronary artery bypass graft surgery, or percutaneous transluminal coronary angioplasty. Exercise protocols included a 5-minute warm-up function followed by either a continuous or an interval training program (12 minutes) and concluded with a 3-minute active recovery. Data were collected at 1-minute intervals at rest, during exercise, and at recovery. Evaluation of the cycle was based upon: continuous HR recordings of the cycle compared to a Quinton 2000 electrocardiographic (ECG) system, the cycle's capability of maintaining the appropriate target HR; and the effect of arrhythmias on the cycle's HR monitoring device and its capability of maintaining the prescribed HR. Validity coefficients between the HR from the cycle compared with the ECG system for all exercise phases were high (r = 0.97 to 0.99). Observed HRs were not significantly different (P > 0.05) from the target HR. Adjustments in the power output were not affected by arrhythmias. These data indicated that the cycle is a valid, safe instrument and is acceptable for home use by selected cardiac patients and in cardiac rehabilitation centers.

ISSN:0883-9212    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

In patients treated with beta-adrenergic blocking agents, the practice of estimating exercise heart rate (HR) from postexercise pulse count may be invalid if beta-adrenergic blockade (BB) shortens the time course of heart rate recovery (heart rate recovery kinetics or HRK) after acute exposure to exercise. To determine the effect of nonspecific BB on HRK in nine healthy, drug-free men, HR was calculated from ECG recordings during submaximal (70. % HR max reserve) cycle ergometer exercise and every 4 seconds for 2 minutes of recovery under both BB (80 mg propranolol) and placebo (PL) treatments (random order, double-blind); half-times of the HR recovery curves were subsequently calculated. Data analysis (2 ± 31 randomized block factorial ANOVA; critical P < 0.05) revealed that: (1) HR was significantly reduced by BB, (2) HR decreased significantly by the twelfth second of recovery, and (3) the treatment-by-time interaction term was not significant suggesting parallelism of the BB and PL HR recovery curves. Polynomial regression demonstrated that a second-order function provided optimal fit of the HRK data under both treatment conditions. In addition, HR recovery curve half-times were similar between treatments (ANOVA, P > 0.05). Finally, HRs calculated from the last 15 seconds of exercise and the first 15 seconds of recovery were not significantly different; ingestion of BB did not affect this finding, although exercise and recovery HRs were reduced by BB treatment. These results demonstrate that HRK is unaffected by acute ingestion of nonspecific BB, and, if the pulse count is completed within the first 15 seconds after exercise cessation, estimating exercise HRs from postexercise pulse counts remains a valid procedure for patients receiving BB.

ISSN:0883-9212    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Behavior modification relating to coronary risk factors was analyzed in 48 post coronary bypass (CABG) patients who participated in an inpatient cardiac rehabilitation program followed by a 12-week home-monitored exercise program. This analysis took place 4 years (± 52.9 months) after the completion of the home-monitored exercise program. Thirty-nine patients (81 %) were available for the 4-year follow-up evaluation. At follow-up, eight (44 %) of the 18 patients who smoked cigarettes continued to smoke (P = <0.01). Twenty-three (59%) of 39 (P = <.05) did not participate in a regular exercise program. Twenty-nine (74%) of 39 patients did not adhere to the American Heart Association (AHA) prudent diet (P = <.01). Six (26%) of 23 hypertensive patients were unaware of their current blood pressure. Twenty-six (81 %) of the 32 patients with elevated cholesterol were unaware of their current cholesterol level. Twenty-nine (74%) overweight patients continued to be over their ideal body weight, and three additional patients exceeded their actual ideal body weight, increasing from ± 79.9 Kg to 82 Kg. The authors conclude that inpatient coronary risk factor education followed by a 12-week home-monitored exercise program does not necessarily enhance long-term risk factor modification in post CABG patients.

ISSN:0883-9212    

出版商:OVID    

年代:1989

数据来源: OVID

ISSN:0883-9212    

出版商:OVID    

年代:1989

数据来源: OVID