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Results for “Walk Test”

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PubMed1996

A six-minute walk test for assessing exercise tolerance in severely ill children.

OBJECTIVES: The primary objective of this study was to compare exercise tolerance, heart rate, and oxyhemoglobin saturation (Sao2) between a traditional progressive maximal exercise test and a self-paced, 6-minute walk test in severely ill children. STUDY DESIGN: Seventeen patients (9 to 19 years of age) performed a progressive maximal exercise test on a cycle ergometer and a self-paced, 6-minute walk test as part of the evaluation for possible heart, lung, or combined heart and lung transplantation. Physical work capacity and peak oxygen uptake were measured during the progressive cycle test. The walk test was performed in a hospital corridor, with patients trying to cover as much distance as possible in 6 minutes at their own pace. Oxyhemoglobin saturation and heart rate were monitored continuously by pulse oximetry and compared between the two tests. RESULTS: The distance walked in 6 minutes correlated with peak oxygen uptake (r = 0.70, p < 0.01) and physical work capacity (r = 0.64, p < 0.005). The minimum (Min) Sao2 on the bike test correlated significantly with Min Sao2 on the walk test (r = 0.82, p < 0.001), with 11 of 17 patients having a lower Min Sao2 on the walk test than the bike test (mean Min Sao2, 84% and 86%, respectively). The peak heart rate did not correlate significantly between the bike and walk tests (r = 0.25), although significantly lower (p < 0.01) values were observed on the walk (148 beats/min) than bike (169 beats/min) test. CONCLUSIONS: The results suggest that the 6-minute self-paced walk test may provide an alternative method for assessing functional capacity in severely ill children, and that Sao2 measured during progressive exercise testing on a cycle ergometer may not reflect the degree of oxyhemoglobin desaturation during self-paced walking in some patients with severe cardiopulmonary disease.

Adolescent↗

PubMed2001

A qualitative systematic overview of the measurement properties of functional walk tests used in the cardiorespiratory domain.

OBJECTIVE: To perform a qualitative systematic overview of the measurement properties of the most commonly utilized walk tests in the cardiorespiratory domain: the 2-min walk test (2MWT), 6-min walk test (6MWT), 12-min walk test (12MWT), self-paced walk test (SPWT), and shuttle walk test (SWT). DATA SOURCES: MEDLINE (1966 to January 2000) and CINAHL (1982 to December 1999) electronic databases were searched. Bibliographies of the retrieved articles were reviewed. STUDY SELECTION: Clinical trials and observational studies were included if they reported data on the validity, reliability, interpretability, or responsiveness of the 2MWT, 6MWT, 12MWT, SPWT, or SWT. Only studies conducted on patients with cardiac and/or respiratory involvement were included. RESULTS: Fifty-two studies examining measurement properties of the various walk tests were found: 5 studies on the 2MWT, 29 studies on the 6MWT, 13 studies on the 12MWT, 6 studies on the SPWT, and 4 studies on the SWT. Measurement properties were most strongly demonstrated for the 6MWT. Correlations of 6MWT distance and maximal oxygen consumption ranged from 0.51 to 0.90. A change in distance walked of at least 54 m was found to be clinically significant for the 6MWT. Reliability was shown to be optimized when the administration of walk tests was standardized and at least two practice walks were performed. Patients with increased likelihood of postoperative complications, hospitalization, and death were identified by analysis of distance walked. CONCLUSIONS: Measurement properties of the 6MWT have been the most extensively researched and established. In addition, the 6MWT is easy to administer, better tolerated, and more reflective of activities of daily living than the other walk tests. Therefore, the 6MWT is currently the test of choice when using a functional walk test for clinical or research purposes.

Adult↗

PubMed2005

Comparison of the 6-minute walk test with established parameters for assessment of cardiopulmonary capacity in adults with complex congenital cardiac disease.

BACKGROUND: Objective assessment of the cardiopulmonary capacity in patients with complex congenital cardiac disease often remains difficult in clinical practice. The cardiopulmonary exercise test and determination of the levels of brain natriuretic peptide in the plasma are established tests, but expensive. The 6-minute walk test is also validated, but has not often been used in patients with heart failure due to congenital heart disease, nor compared with other tests. We sought to compare its value with the results of cardiopulmonary exercise testing and measuring the levels of brain natriuretic peptide in the plasma. METHODS: We carried out a standardized 6-minute walk test in 31 patients with complex congenital cardiac disease on the same day that they underwent cardiopulmonary exercise testing and determination of levels of brain natriuretic peptide in the plasma. Of the patients, 7 had functionally univentricular hearts, 9 had transposition, 9 had tetralogy of Fallot, 3 had common arterial trunk, and 3 had pulmonary atresia with intact interventricular septum. Uptakes of oxygen at peak exercise, and at the anaerobic threshold, were determined using cardiopulmonary exercise testing, and classified as suggested by Weber. The 6-minute walk test was performed according to a standard protocol. RESULTS: There was a significant correlation between brain natriuretic peptide, oxygen uptakes at peak exercise and 6-minute walk. The correlation between the 6-minute walk test and oxygen uptakes at the anaerobic threshold, however, was not significant. CONCLUSIONS: The 6-minute walk test can be performed easily, is inexpensive, widely available, and correlates well with measurements of brain natriuretic peptide and cardiopulmonary exercise testing, even in patients with corrected or palliated congenital cardiac malformations. A cut-off value of 450 metres in the 6-minute walk test allows a semi-quantitative classification in analogy to the classification suggested by Weber for cardiopulmonary exercise testing, and to a level of brain natriuretic peptide in the plasma of less or more than 100 picograms per millilitre.

Adult↗

PubMed2005

[Use of the six-minute walk test in cardiology].

The symptom-limited exercise test is nowadays the gold standard to assess the exercise tolerance and the effects of different treatments in patients with chronic heart failure (CHF). A simpler alternative to this test is the 6-minute walk test. The 6-minute walk test is easy to realize and well-tolerated. Moreover, it is reliable just after one familiarization practice and requires standardization. Indeed, its conduction, which is submitted to some security precautions, can be altered by variation factors. The distance walked during the 6 minutes was the only parameter studied during the test. This parameter could allow judging the CHF severity and prognostic. The analyse of cardiorespiratory parameters has shown that the 6-minute walk test relative intensity is near to the peak individual values. Moreover, the cardiac and ventilatory adaptation of patient during this test depends to his own functional capacity. Lastly, the 6-minute walk test is a submaximal constant-load exercise, which should be performed in complement to the symptom-limited exercise test in cardiac patients.

Exercise Test↗

PubMed1997

[Comparison of a shuttle walking test with an exertion test with cycloergometer in patients with COPD].

To validate a shuttle walking test in a group of patients with COPD, comparing responses to those produced by a conventional stress test limited by symptoms on the cycle ergometer, and to analyze the relation between the shuttle walking test and maximal effort parameters. We enrolled 20 patients with COPD, mean age 60 years (SD 7), FEV1/46.6% (SD 19.2) of theoretical value and FEV1/FVC% 47.3% (SD 11.2). All the patients underwent a maximal effort test on the cycle ergometer, determination of initial dyspnea by applying Mahler's baseline dyspnea index, and a quality of life questionnaire specific to COPD the Chronic Respiratory Disease Questionnaire). To compare the responses of patients to the two tests, we analyzed heart rate, dyspnea and lactic acid at the end of each test. To see the relations between the two tests, we examined distance walked and maximal effort parameters. The relation between the walking test and lung function parameters at rest, initial dyspnea and quality of life were also analyzed. No statistically significant differences were found for heart rate [128.2 (SD 19.8) versus 131.6 (SD 12.9)], dyspnea 17.1 (SD 1.78) versus 7.24 (SD 2.64)] or lactic acid [5.24 (SD 2.34) versus 6.19 (SD 2.12)] at the end of the tests. Distance covered on the shuttle walking test correlated significantly with V'O2ml/min/Kgmax (r = 0.71), as well as with the remaining parameters of maximal effort. There was only a slight relation between lung function at rest and quality of life. The COPD patient's cardiovascular, metabolic and subjective responses to the shuttle walking test are similar to those of the cycle ergometer test, and oxygen consumption is significantly correlated. The shuttle walking test gives a valid estimate of the functional capacity of COPD patients.

Exercise Test↗

PubMed2005

Assessing walking ability in subjects with spinal cord injury: validity and reliability of 3 walking tests.

OBJECTIVE: To assess the validity and reliability of 3 timed walking tests (Timed Up & Go [TUG], 10-meter walk test [10MWT], 6-minute walk test) in subjects with spinal cord injury (SCI). DESIGN: Cross-sectional study and repeated assessments. SETTING: The SCI center of a university hospital in Switzerland. PARTICIPANTS: Validity was assessed by using the data of 75 patients with SCI, and reliability was determined with 22 patients with SCI. INTERVENTION: Patients performed the timed tests and the Walking Index for Spinal Cord Injury II (WISCI II) on the same day. Three measurements within 7 days were taken to assess reliability. MAIN OUTCOME MEASURES: The measures were scatterplots, correlation coefficients ( r ), and the Bland-Altman plot. Validity was determined in patients with different walking abilities. RESULTS: Overall, correlation of the 3 timed walking tests was excellent with each other (| r |>.88) and moderate with the WISCI II (| r |>.60). The correlation between the timed tests for patients with poor walking ability remained high (| r |>.70) but decreased in WISCI II (| r |<.35). High correlation coefficients ( r >.97) were found for intra- and interrater reliability. However, TUG and 10MWT reliability were negatively influenced by a poor walking function. CONCLUSIONS: The 3 timed tests are valid and reliable measures for assessing walking function in patients with SCI.

Adolescent↗

PubMed2001

Feasibility of fitness tests in subjects with chronic pain (fibromyalgia): discordance between cycling and 2-km walking tests.

Altogether, 69 out of 98 fibromyalgia (FMS) patients who attended a 2-week multidisciplinary inpatient course and a 1-week control period 3 months later completed 2-km walking tests and stepwise-increased cycling tests at entry and after 3 months. The purpose was to compare the feasibility of the two fitness tests for assessment of FMS patients. The results showed a substantially lower fitness level in the results of the 2-km walking test than in the cycling test in the same patients: mean maximum VO2 was 28.5 ml/kg per min vs 34.6 ml/kg per min, respectively. At entry and after the 3-month training period, the correlations between the two tests were very poor, i.e., with Spearman's r coefficients of 0.37 and 0.34, respectively (P < 0.01), intraclass correlation coefficients (ICC) 0.20 (95% CI -0.29 to 0.50) and 0.47 (95% CI 0.15 to 0.67), reliability coefficients (alpha) 0.54 and 0.47, and Kendal-T coefficients 0.32 and 0.41 for ordinal correlation of the test results. The results did not correlate with pain, which remained at initial levels for the 3 months of follow-up. Principally, these tests should both measure the same property, i.e., the fitness of fibromyalgia syndrome (FMS) patients, but the results differed substantially. The 2-km walking test showed a markedly lower fitness level than the cycling test in the same patients. The primary explanation for this difference might be difficulties in controlling test performance. especially in walking. The 2-km walking test would not appear recommendable for subjects with chronic pain syndrome, e.g., fibromyalgia.

Adult↗

PubMedDate not supplied

A simple walk test to guide exercise programming of the elderly.

Exercise training programs are usually based on a maximal exercise stress test; however, this test is often difficult and sometimes frightening to older persons. This preliminary study reports on a fixed-distance, submaximal walk test and compares its usefulness for exercise prescription to that of the traditional maximal stress test. Ten cardiac patients, with an average age of 72 years (4 men), had recently clinically indicated maximal graded stress tests. Within one week, each had the walk test, which consisted of walking three times up and back 100 feet in the hospital corridor (total of 600 feet) as rapidly as possible, with a blood pressure cuff on their arm and carrying the electrocardiogram cable. Resting and peak heart rate, blood pressure, symptoms, and exercise electrocardiograms were compared for the walk test v the maximal stress test. Oxygen consumption was calculated from the peak workload on the maximal stress test and from walking speed on the walk test. The peak heart rates after the walk test were within the target heart rate zone (70-85%) for exercise programming, as obtained from the maximal stress test, in all patients except one. The calculated peak oxygen consumption from the walk test was also within the training zone (60-80%) obtained from the maximal stress test in all patients except one. This pilot study shows that a submaximal, steady state timed walk of 600 feet can be a feasible method of providing the information for exercise programming, possibly avoiding the need for a maximal stress test. This walk test can be performed easily by health-related staff without sophisticated facilities in an inpatient rehabilitation unit or nursing home; however, further study with a larger number of patients is necessary before this method of exercise prescription can be recommended.

Aged↗

PubMed2000

Is the 6-minute walk test a reliable substitute for peak oxygen uptake in patients with dilated cardiomyopathy?

AIMS: The 6-min walk test may serve as a more simple clinical tool to assess functional capacity in congestive heart failure than determination of peak oxygen uptake by cardiopulmonary exercise testing. The purpose of the study was to prospectively examine whether the distance ambulated during a 6-min walk test (i) correlates with peak oxygen uptake, (ii) allows peak oxygen uptake to be predicted, and (iii) provides prognostic information similar to peak oxygen uptake in patients with dilated cardiomyopathy and left ventricular ejection fraction < or = 35%. METHODS AND RESULTS: In 113 patients (age: 54+/-12 years, NYHA: 2.2+/-0.8) with dilated cardiomyopathy (left ventricular ejection fraction 19+/-7%) a 6-min walk test and cardiopulmonary exercise testing were performed. The 6-min walk test and peak oxygen uptake were closely correlated at the initial visit (r=0.68, n=113), as well as after 263+/-114 (r=0.71, n=28) and 381+/-170 days (r=0.74, n=14). During serial exercise testing the 6-min walk test allowed peak oxygen uptake to be reliably predicted (r=0.76 between calculated and real peak oxygen uptake). After 528+/-234 days, 42 patients were hospitalized due to worsening heart failure and/or died from cardiovascular causes. Compared to clinically stable patients, these 42 patients walked a shorter distance (423+/-104 vs 501+/-95 m, P<0.001) and had a lower peak oxygen uptake (12.7+/-4.0 vs 17.4 + 5.6 ml x min(-1) x kg(-1), P<0.001). By univariate analysis the 6-min walk test outperformed other prognostic parameters such as left ventricular ejection fraction, cardiac index and plasma norepinephrine concentration and conferred a prognostic power similar to peak oxygen uptake. This predictive value could be further improved in a multivariate model, by combining the 6-min walk test with independent variables, such as left ventricular ejection fraction or cardiac index. CONCLUSION: The 6-min walk test correlated with peak oxygen uptake when tested serially over the course of the disease. Although both tests define two distinct domains of functional capacity, the 6-min walk test provides prognostic information very similar to peak oxygen uptake in congestive heart failure patients with dilated cardiomyopathy.

Aged↗

PubMed1999

[Reproducibility of the walking test in patients with cystic fibrosis].

OBJECTIVE: The walking test is a useful and objective method for evaluating the tolerance for exercise in patients with chronic bronchopulmonary diseases. Our objective was to check the reproducibility of this test and evaluate whether there are differences between tests of varying duration (2 and 6 minutes) in a group of patients with cystic fibrosis. PATIENTS AND METHODS: We utilized the walking test on 29 patients who were in a stable phase and under care in the Cystic Fibrosis Unit of our hospital. Two tests were carried out, one of 2 minutes and the other of 6 minutes duration, both of which were repeated after a 15-minute interval. RESULTS: The reproducibility of the walking test in this type of patient was very good and we found an excellent correlation between the two-minute test and the six-minute test. We did not observe a training effect when the test was repeated. CONCLUSIONS: The two minute walking test has a high reproducibility and we propose this test, because it is shorter and more comfortable for pediatric patients with cystic fibrosis, in order to evaluate the evolution, progressive deterioration of the of the patient and the response to different types of treatments.

Adolescent↗

PubMed2002

Can the cardiopulmonary 6-minute walk test reproduce the usual activities of patients with heart failure?

OBJECTIVE: The 6-minute walk test is an way of assessing exercise capacity and predicting survival in heart failure. The 6-minute walk test was suggested to be similar to that of daily activities. We investigated the effect of motivation during the 6-minute walk test in heart failure. METHODS: We studied 12 males, age 45 +/- 12 years, ejection fraction 23 +/- 7%, and functional class III. Patients underwent the following tests: maximal cardiopulmonary exercise test on the treadmill (max), cardiopulmonary 6-minute walk test with the walking rhythm maintained between relatively easy and slightly tiring (levels 11 and 13 on the Borg scale) (6EB), and cardiopulmonary 6-minute walk test using the usual recommendations (6RU). The 6EB and 6RU tests were performed on a treadmill with zero inclination and control of the velocity by the patient. RESULTS: The values obtained in the max, 6EB, and 6RU tests were, respectively, as follows: O2 consumption (ml.kg-1.min-1) 15.4 +/- 1.8, 9.8 +/- 1.9 (60 +/- 10%), and 13.3 +/- 2.2 (90 +/- 10%); heart rate (bpm) 142 +/- 12, 110 +/- 13 (77 +/- 9%), and 126 +/- 11 (89 +/- 7%); distance walked (m) 733 +/- 147, 332 +/- 66, and 470 +/- 48; and respiratory exchange ratio (R) 1.13 +/- 0.06, 0.9 +/- 0.06, and 1.06 +/- 0.12. Significant differences were observed in the values of the variables cited between the max and 6EB tests, the max and 6RU tests, and the 6EB and 6RU tests (p < 0.05). CONCLUSION: Patients, who undergo the cardiopulmonary 6-minute walk test and are motivated to walk as much as they possibly can, usually walk almost to their maximum capacity, which may not correspond to that of their daily activities. The use of the Borg scale during the cardiopulmonary 6-minute walk test seems to better correspond to the metabolic demand of the usual activities in this group of patients.

Activities of Daily Living↗

PubMed1992

Development of a shuttle walking test of disability in patients with chronic airways obstruction.

BACKGROUND: The aim was to develop a standardised and externally paced field walking test, incorporating an incremental and progressive structure, to assess functional capacity in patients with chronic airways obstruction. METHODS: The usefulness of two different shuttle walking test protocols was examined in two separate groups of patients. The initial 10 level protocol (group A, n = 10) and a subsequent, modified, 12 level protocol (group B, n = 10) differed in the number of increments and in the speeds of walking. Patients performed three shuttle walking tests one week apart. Then the performance of patients (group C, n = 15) in the six minute walking test was compared with that in the second (modified) shuttle walking test protocol. Heart rate was recorded during all the exercise tests with a short range telemetry device. RESULTS: The 12 level modified protocol provided a measure of functional capacity in patients with a wide range of disability and was reproducible after just one practice walk; the mean difference between trial 2 v 3 was -2.0 (95% CI -21.9 to 17.9) m. There was a significant relation between the distance walked in the six minute walking test and the shuttle walking test (rho = 0.68) but the six minute walking test appeared to overestimate the extent of disability in some patients. The shuttle test provoked a graded cardiovascular response not evident in the six minute test. Moreover, the maximal heart rates attained were significantly higher for the shuttle walking test than for the six minute test. CONCLUSIONS: The shuttle walking test constitutes a standardised incremental field walking test that provokes a symptom limited maximal performance. It provides an objective measurement of disability and allows direct comparison of patients' performance.

Aged↗

PubMedDate not supplied

Shuttle versus six-minute walk test in the prediction of outcome in chronic heart failure.

We prospectively analysed the potential usefulness of a symptom-limited walk test, the shuttle walk test (SWT), in the prediction of major cardiac events in 46 consecutive patients with chronic heart failure (NYHA class II-IV, ejection fraction <0.40) and compared it with that of a time-limited walk test, the six-minute walk test (6-MT). After a mean follow-up of 17 months (range, 8-28 months), 15 of 46 patients (33%) experienced a major cardiac event, defined as a cardiac death, urgent transplantation, or hospital admission for continuous inotropic or mechanical support. Distance walked in the SWT was shown to be a predictor of outcome at one year of follow-up (P=0.03), but distance ambulated in the 6-MT was not (P=0.07). In multivariate analysis, percentage of age-gender predicted peak oxygen uptake was the best predictor of major cardiac events. When patients were divided into tertiles according to performance in both walk tests, there was an overall difference in event-free survival at 12 months among SWT tertiles (P=0.004), but not among 6-MT tertiles (P=0.09). A low performance in the SWT (distance ambulated <450 m) allowed identification of a subgroup of patients with a high risk for major cardiac events at short-term. We conclude that, in patients with chronic heart failure, distance ambulated in the SWT predicts event-free survival at one year better than that in the 6-MT.

Exercise Test↗

PubMed2005

[Efficacy of the 6-minute walk test in evaluating ambulatory oxygen therapy].

OBJECTIVE: To compare oxyhemoglobin saturation (SpO2) observed during the 6-minute walk test with that of pulse oximetry carried out during activities of daily living (ADLs). The efficacy of the 6-minute walk test for determining adequate oxygen flow to prevent arterial desaturation during ADLs was also analyzed. PATIENTS AND METHODS: We studied 37 patients diagnosed with chronic obstructive pulmonary disease (COPD)--mean (SD) forced expiratory volume in 1 second, 26% (9%) of predicted--and compared SpO2 values obtained in the 6-minute walk test with those obtained with ambulatory pulse oximetry during ADLs. Eleven of the 20 patients with exercise-induced desaturation agreed to use portable liquid oxygen and were randomized to ambulatory pulse oximetry on 2 consecutive days, both with and without the administration of oxygen. Oxygen flow was adjusted on successive 6-minute walk tests until a mean SpO2 greater than 85% was reached. RESULTS: The mean SpO2 for all patients was 84% (7%) during the 6-minute walk test and 89% (4%) during ADLs (P<.001). Cumulative percentages of time with SpO2 less than 90%, 88%, and 85% were higher during the 6-minute walk test than during ADLs (P<.001). During the walk test, desaturation was detected in 27% of patients, but was not confirmed by ambulatory pulse oximetry during ADLs. In the subgroup of 11 patients using portable liquid oxygen no significant differences were found between SpO2 values recorded during the walk test and during ADLs with the appropriate oxygen flow. CONCLUSION: The 6-minute walk test is an effective method for detecting desaturation during ADLs and for establishing the oxygen flow needed to correct exercise-induced desaturation.

Aged↗

PubMed2005

[Walking tests: a step forward for functional cardiorespiratory assessment].

Exercise testing provides information on physical capacity during exercise in addition to spirometric measures of lung function or assessment on treadmills or ergonomic cycle. The "gold standard" assessment of exercise tolerance is measured in the laboratory using treadmills or ergonomic cycle but the necessary equipment is expensive and may not be readily accessible; such tests require people used to work with children. Walking tests are field tests providing a valid and easily accessible method of measuring function-limited exercise tolerance in patients with respiratory or cardiac chronic diseases. These walking tests are non-threatening, inexpensive, easy to perform and to understand for children. Walking tests performed in daily practice are the following: "time-based" tests (2-, 6- or 12-min walking test), 3-min step test (on a step) and the shuttle walking test. It may be a useful measure to assess therapeutic intervention and provide information on the prognosis. They are simple and safe methods to evaluate quality of life in these patients.

Adolescent↗

PubMed1997

Cross validation of the 1-mile walking test for men with mental retardation.

The purpose of this study was to cross validate the equation developed by Rintala et al. (1992) to estimate the cardiorespiratory efficiency of men with mental retardation (MR). Subjects were 19 healthy men (27 +/- 8 yr) with MR (IQ = 58 +/- 12). Following familiarization, a graded maximal treadmill test and two 1-mile walk tests (Rockport Fitness Walking Test, RFWT) were administered. The peak VO2 value was the criterion measure used to cross validate the equation. The equation was: Peak VO2 (ml.kg-1.min-1) = 101.92 - 2.356 (MILE)-0.420 (WEIGHT). The mean differences were 2.04 (MILE1)(P = 0.02) and 2.43 (MILE2)(P = 0.004) ml.kg-1.min-1. A significant positive correlation was found between measured peak VO2 and predicted peak VO2 on both 1-mile walks (r = 0.91 and 0.93). For both predicted peak VO2 values, the Total Error (TE) was greater than standard error of estimate (SEE), indicating a systematic difference between the measured and predicted peak VO2 values. Moreover, only 58% of the measured peak VO2 values fell within the prespecified range. Test-retest reliability of RFWT was R = 0.96. However, the prediction equation underestimated the actual cardiorespiratory levels in 74% and 79% of the subjects, depending on the trial. Because the equation developed in this research underestimates the measured VO2 values for the majority of these subjects, the test is probably not statistically valid, even if reliable, and the prediction formula needs to be revised for this population.

Adult↗

PubMed1999

A shuttle walk test for assessment of functional capacity in chronic heart failure.

BACKGROUND: Peak oxygen uptake (peak VO(2)) is a reference parameter in the assessment of functional capacity of patients with chronic heart failure, but the procedure for cardiopulmonary exercise testing with expired gas analysis is complex and expensive, so more simple and available methods are desirable. METHODS: We compared the usefulness of a time-limited walk test, the 6-minute walk test (6-MT), with that of a symptom-limited walk test, the shuttle walk test (SWT), in the evaluation of patients with moderate to severe chronic heart failure. We prospectively studied 46 clinically stable patients in New York Heart Association class II to IV heart failure with left ventricular ejection fraction <40% (aged 53 +/- 10 years, ejection fraction 23% +/- 8%, New York Heart Association functional class 2.8 +/- 0.7). Each patient performed two 6-MT, two SWT and a cardiopulmonary exercise testing within 2 weeks. RESULTS: We found a close correlation between distance walked in SWT and peak VO(2 ) (r = 0.83, P <.001) and a moderate correlation between distance in 6-MT and peak VO(2) (r = 0.69, P <.001). Both walk tests showed to be reproducible after just one practice walk. All patients who walked > 450 m in SWT had a peak VO(2) >14 mL/kg/min. The overall discriminatory accuracy for SWT distance was greater than that for 6-MT distance for predicting a peak VO(2 ) <14 mL/kg/min (area under receiver operator characteristic curves 0.97 and 0.83 respectively, P =.02). Stepwise multivariate regression analysis, including clinical, exercise testing, echocardiographic, radionuclide-angiographic, and rest hemodynamic data, showed that distance walked in SWT was the only independent predictor of peak VO(2) (P <.001) and the strongest predictor of percent achieved of age- and sex-predicted peak VO(2) (%PVO(2)) (P <.001), with only age offering additional information (P =.02). CONCLUSIONS: The SWT shows to be a feasible and safe method to evaluate patients with chronic heart failure that strongly and independently predicts peak VO(2) and %PVO(2.) This symptom-limited walk test seems to be more useful than 6-MT in the assessment of functional capacity in these patients.

Adult↗

PubMed2002

Functional walk tests in individuals with stroke: relation to perceived exertion and myocardial exertion.

BACKGROUND AND PURPOSE: Functional walk tests such as the 6- and 12-Minute Walk Test (ie, 6MWT and 12MWT, respectively) are submaximal measures used to determine functional capacity in individuals with compromised ability. The purpose of this study was to determine the relationship between these walk tests and measures of exertion (perceived and myocardial), in addition to impairment in individuals with stroke. The relationship among the 6MWT, 12MWT, and the more traditionally assessed measure of self-paced gait speed (generally assessed over a short distance, eg, 10 m) was also evaluated. METHODS: Twenty-five community-dwelling individuals with stroke were evaluated for the following: 12MWT distance, 6MWT distance, self-paced gait speed over 8 m, plantarflexion strength, Berg Balance Scale, Ashworth Scale of Spasticity, and Chedoke-McMaster Stroke Assessment. Heart rate (HR), rate-pressure product (RPP), and perceived exertion were assessed during the functional walk tests. Correlational analysis quantified the relationship between gait, impairment measures, and physiological responses during the functional walk tests. RESULTS: HR reached a steady state after 6 minutes and reflected a moderate exercise intensity of 63% of age-predicted maximum HR. The 6MWT, 12MWT, and self-paced gait speed were all highly correlated with one another (r>0.90) and were all also related to the severity of impairments. The functional walk distances did not relate either to perceived exertion or actual exertion (increase in the myocardial oxygen demand as measured by RPP). CONCLUSIONS: Stroke-specific impairments are the major limitations to the distance walked in individuals with stroke. If the functional walk test is used to assess performance of an individual over time (eg, in response to an intervention), we recommend that both exertion (eg, increase in RPP or HR) and distance be measured.

Aged↗