Jean-Marie Casillas

Determining the Minimal Clinically Important Difference for the Six-Minute Walk Test and the 200-Meter Fast-Walk Test During Cardiac Rehabilitation Program in Coronary Artery Disease Patients After Acute Coronary Syndrome

OBJECTIVE To estimate the minimal clinically important difference (MCID) for the 6-minute walk test (6MWT) and the 200-m fast-walk test (FWT) in patients with coronary artery disease (CAD) during a cardiac rehabilitation program. DESIGN Prospective study using distribution- and anchor-based methods. SETTING Outpatients from a cardiac rehabilitation unit. PARTICIPANTS Stable patients with CAD (N=81; 77 men; mean±SD age, 58.1±8.7y) enrolled 31±12.1 days after an acute coronary syndrome (ACS). INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES 6MWT and 200-m FWT results before and after an 8-week cardiac rehabilitation program and at the 6th and 12th sessions. Patients and physiotherapists who supervised the training were asked to provide a global rating of perceived change in walking ability while blinded to changes in walk test performances. RESULTS Mean change in 6MWT distance (6MWD) in patients who reported no change was -6.5m versus 23.3m in those who believed their performance had improved (P<.001). This result was consistent with the MCID determined by using the distribution method (23m). Considering a 25-m cutoff, positive and negative predictive values were 0.9 and .63, respectively. Conversely, there was no difference in 200-m FWT performance between these 2 groups (0.1 vs -1.4s, respectively). There was poor agreement with the physiotherapists perceived change. CONCLUSIONS The MCID for 6MWD in patients with CAD after ACS was 25m. This result will help physicians interpret 6MWD change and help researchers estimate sample sizes in further studies using 6MWD as an endpoint.

Effects of low-frequency electrical stimulation of quadriceps and calf muscles in patients with chronic heart failure.

PURPOSE The aim of this preliminary study was to evaluate the effects of low-frequency electrical stimulation of quadriceps and calf muscles on global exercise capacities, skeletal muscle metabolism, calf muscle volume, and cardiac output in patients with chronic heart failure. METHODS Fourteen patients with chronic heart failure (mean age of 56.4 years +/- 9.1 SD; mean radionuclide left ventricular ejection fraction of 22.3% +/- 8.8 SD) underwent 5 weeks (1 hour per day, 5 days per week) of low-frequency electrical stimulation of quadriceps and calf muscles. RESULTS Low-frequency electrical stimulation was well tolerated. Exercise capacity and the calf muscles volumes increased significantly after rehabilitation in comparison with prior rehabilitation (the peak oxygen consumption increased from 17.2 mL/(kgmin) +/- 5.3 SD to 19.6 mL/(kgmin) +/- 5.9 SD; the anaerobic threshold increased from 12.3 mL/(kgmin) +/- 3.2 SD to 15.2 mL/(kgmin) +/- 3.3 SD; the 6-minute walking test increased from 419 m +/- 122 SD to 459 m +/- 114.3 SD; the gastrocnemius volume increased from 259.4 cm3 +/- 58 SD to 273.4 cm3 +/- 74 SD, and the soleus volume increased from 319 cm3 +/- 42.9 SD to 338 cm3 +/- 52.5 SD). The New York Heart Association class was improved after rehabilitation. The P-31 nuclear magnetic resonance spectroscopy of gastrocnemius muscle data were not significantly modified after rehabilitation, thereby inferring that no significant improvement of the muscle metabolism occurred. These data reinforce the hypothesis of an increased muscle mass during stimulation. It is noteworthy that the electrical stimulation did not increase cardiac output at any stage; an enormous asset in favor of this mode of rehabilitation. CONCLUSION These results suggest that low-frequency muscular electrical stimulation is well tolerated, induces an increased exercise capacity in patients with chronic heart failure, without an undesirable increase in cardiac output.

Bioenergetic comparison of a new energy-storing foot and SACH foot in traumatic below-knee vascular amputations

In this study, the metabolic performances of a new energy-storing foot (Proteor) and of the solid-ankle cushion heel (SACH) are compared. Twelve patients with traumatic below-knee amputations (mean age: 50.0 +/- 19.9 years) and 12 patients with vascular below-knee amputations (mean age: 73 +/- 7 years) were studied. Oxygen uptake (VO2) was measured in all the subjects on a walkway at a self-selected velocity; only the subjects with traumatic amputation were tested on a level treadmill (progressive speed: 2.4-4 and 6 km/h), and then in two randomized trials: incline (+5%) and decline walking treadmill test at 4 km/h. Vascular explorations were done in the vascular patients: distal pressure measurements, pulse plethysmography, transcutaneous oxygen tension. Free walking was improved in subjects with traumatic amputation using the energy-storing foot (+6%), with a better bioenergetic efficiency (0.24 +/- 0.4mL/kg.m vs 0.22 +/- 0.04mL/kg.m). However, in subjects with vascular amputation, this foot did not produce an increased free velocity nor an improved energy cost. During the level treadmill test, the traumatic amputee subjects showed a decrease of energy expenditure with the new prosthetic foot, more significant at sufficient speed (4 km/h): 17.00 +/- 3.42 vs 14.67 +/- 2.05 mL/kg/min (p < .05). The same effect is shown during the incline (19.31 +/- 2.80 vs 16.79 +/- 2.32 mL/kg/min-p < .02) and decline walking tests (14.13 +/- 3.64 vs 11.81 +/- 1.54mL/kg/min-p < .02). There is no significant difference in cardiocirculatory effects between the two types of prosthetic foot. Despite a lower velocity, the subjects with vascular amputation exceed 70% of the maximal heart rate, with the cardiocirculatory factor being the main cause of walking restriction. The energy-storing foot should be reserved for active and fast walkers, whereas the SACH foot seems more suitable for elderly patients with amputation with a slow walk.

Poststroke Disposition and Associated Factors in a Population-Based Study The Dijon Stroke Registry

Background and Purpose— The organization of poststroke care will be a major challenge in coming years. We aimed to assess hospital disposition after stroke and its associated factors in clinical practice. Methods— All cases of stroke from 2006 to 2010 were identified from the population-based Stroke Registry of Dijon, France. Demographic features, risk factors, and prestroke treatments were recorded. Admission stroke severity was assessed using the National Institutes of Health Stroke Scale score. At discharge, we collected dementia, disability using the modified Rankin Scale, length of stay, and hospital disposition (home, rehabilitation, convalescent home, and nursing home). Multivariate analyses were performed using logistic regression models to identify associated factors of postdischarge disposition. Results— Of the patients with 1069 stroke included, 913 survived acute care. Among them, 433 (47.4%) returned home, whereas 206 (22.6%) were discharged to rehabilitation, 134 (14.7%) were admitted to a convalescent home, and 140 (15.3%) to a nursing home. Old patients, those under anticoagulants before stroke, those with severe stroke on admission, severe disability at discharge, dementia, or prolonged length of stay were less likely to return home. Moreover, advanced age, severe initial stroke, severe disability at discharge, and dementia were associated with admission to convalescent and nursing homes rather than rehabilitation centers. Conclusion— This population-based study demonstrated that postdischarge destinations are associated with several factors. Our findings may be useful to establish health policy concerning the organization of poststroke care.

Healing of open stump wounds after vascular below-knee amputation : plaster cast socket with silicone sleeve versus elastic compression

OBJECTIVE To assess the effect of a plaster cast socket on the healing of open wounds and on temporary prosthesis fitting after below-knee amputation because of arterial occlusive disease. DESIGN Randomized controlled trial. SETTING Rehabilitation center, university hospital. PATIENTS All included patients had undergone recent (in the previous 3 months) below-knee amputation because of arterial disease and initially had an open stump. Patients were randomly assigned to two groups of 28 subjects each. The sizes of the amputation scars were 8 to 24 cm2. Ischemia of the stump was eliminated as a probable cause of delayed wound healing by the inclusion criterion of transcutaneous oxygen tension (TcPO2) of >35 mmHg. The average age in group I (the experimental group) was 65.2 +/- 12.4 (SD) years and in group II (the control group) 66.8 +/- 10.8 years (not significant). INTERVENTION A plaster cast (supracondylar-type) socket was fitted on the stumps of group I patients, interposed with a silicone sleeve. The patients were gradually trained to wear this cast for up to 5 hours a day. They were provided with elastic compression bandages for the remainder of the time. Patients in group II wore elastic compression bandages, which were only removed for dressing changes. MAIN OUTCOME MEASURES Time required for stump healing, length of time between amputation and ability to walk wearing a contact socket, and length of hospital stay. RESULTS Group I had a quicker average healing time (71.2 +/- 31.7 [SD] days compared to the control groups 96.8 +/- 54.9 days) and a shorter average length of hospital stay (99.8 +/- 22.4 days compared to the control groups 129.9 +/- 48.3 days). CONCLUSION Use of a plaster cast socket leads to more rapid healing of the open stump and to a shorter hospitalization. If there is no stump ischemia, this plaster cast technique is safe.

Does eccentric endurance training improve walking capacity in patients with coronary artery disease? A randomized controlled pilot study:

Objective: To examine the effect of eccentric endurance training on exercise capacities in patients with coronary artery disease. Design: Randomized parallel group controlled study. Setting: Cardiac rehabilitation unit, Dijon University Hospital. Participants: Fourteen patients with stable coronary artery disease after percutaneous coronary intervention. Intervention: Patients followed 15 sessions of training (1 session per day, 3 days a week), either in the concentric group, following a standard programme, or in the eccentric group, performing eccentric resistance exercises using both lower limbs on a specifically designed ergometer. Main outcomes measured: Symptom-limited Vo2, peak workload, isometric strength of leg extensor and ankle plantar flexors, distance covered during the 6-minute walk test and time to perform the 200-m fast walk test in both groups, before and after the training period. Results: Patients did not report any adverse effects and were highly compliant. All measured parameters improved in eccentric and concentric group, except for 200-m fast walk test: symptom-limited Vo2 (+14.2% versus +4.6%), peak workload (+30.8% versus +19.3%), 6-minute walk test distance walked (+12.6% versus +10.1%) and leg extensor strength (+7% versus +13%) improved to a similar degree in both groups (P<0.01); ankle plantar flexor strength improved in both groups with a significantly greater increase in the eccentric group (+17% versus +7%, P<0.05). Conclusion: Patients with stable coronary artery disease can safely engage in eccentric endurance training, which appears to be as efficient as usual concentric training, with reduced oxygen consumption.

Comparative analysis of oxygen uptake in elderly subjects performing two walk tests: the six-minute walk test and the 200-m fast walk test

Objective: A novel walk test is proposed to assess the ability of elderly subjects to sustain a submaximal effort in ecological surroundings. Vo2 uptake during this test was compared with that of a six-minute walk test and maximal exercise test. Design: Descriptive laboratory study. Setting: Rehabilitation department, Dijon University Hospital. Subjects: Thirty-one subjects, aged from 70 to 85 years, free from any chronic disease. Intervention: Three tests to assess physical capacities: the 200-m fast walk test (200 mFWT), the six-minute walk test (6 MWT) at self-paced speed, and one maximal cardiorespiratory exercise test on an ergocycle. Main measures: Distance walked on the 6 MWT, time to perform the 200 mFWT. Heart rate (HR) and oxygen uptake (Vo2) were measured for each test. Results: All subjects successfully completed the two walk tests without any complaints. They walked more quickly during the 200 mFWT than during the 6 MWT (mean (SD) speed respectively 1.60 (0.17) versus 1.23 (0.16) m/s, P<0.001). Compared with the maximal exercise test, the relative intensity was much higher during the 200 mFWT than during the 6 MWT (mean (SD) Vo2 uptake 86.8 (8.9)% versus 67.4 (10.7)% of peak Vo2, mean (SD) HR 89.9 (9.4) versus 76.2 (0.8)% of peak HR; P<0.001). Conclusion: In healthy elderly subjects, the 200 mFWT requires a more sustained effort than the 6 MWT. This test is simple, ecological and well tolerated. In addition to the 6 MWT, the 200 mFWT could be a useful tool to build up and evaluate training or rehabilitation programmes, especially when interval training is planned

Low-Frequency Electric Muscle Stimulation Combined With Physical Therapy After Total Hip Arthroplasty for Hip Osteoarthritis in Elderly Patients: A Randomized Controlled Trial

OBJECTIVE To assess the effects of low-frequency electric muscle stimulation associated with usual physiotherapy on functional outcome after total hip arthroplasty (THA) for hip osteoarthritis (OA) in elderly subjects. DESIGN Randomized controlled trial; pre- and posttreatment measurements. SETTING Hospital rehabilitation department. PARTICIPANTS Subjects (N=29) referred to the rehabilitation department after THA for hip OA. INTERVENTIONS The intervention group (n=16; 78+/-8 y) received simultaneous low-frequency electric muscle stimulation of bilateral quadriceps and calf muscles (highest tolerated intensity, 1h session, 5 d/wk, for 5 weeks) associated with conventional physical therapy including resistance training. The control group (n=13; 76+/-10 y) received conventional physical therapy alone (25 sessions). MAIN OUTCOME MEASURES Maximal isometric strength of knee extensors, FIM instrument, before and after; a six-minute walk test and a 200 m fast walk test, after; length of stay (LOS). RESULTS Low-frequency electric muscle stimulation was well tolerated. It resulted in a greater improvement in strength of knee extensors on the operated side (77% vs 23%; P<.01), leading to a better balance of muscle strength between the operated and nonoperated limb. The low-frequency electric muscle stimulation group also showed a greater improvement in FIM scores, though improvements in the walk tests were similar for the 2 groups, as was LOS. CONCLUSIONS Low-frequency electric muscle stimulation is a safe, well-tolerated therapy after THA for hip OA. It improves knee extensor strength, which is one of the factors leading to greater functional independence after THA.

Nuclear magnetic resonance evidence of different muscular adaptations after resistance training

OBJECTIVE To evaluate muscle bioenergetics, muscle cross-sectional area (CSA), and soreness when the gastrocnemius was subjected to concentric and concentric/eccentric resistance training modes. DESIGN Prospective study, before and after training. The subjects served as their own controls. SETTING Rehabilitation center and nuclear magnetic resonance spectroscopy unit of a university hospital. PARTICIPANTS Sixteen healthy young volunteers from the local physiotherapist school. INTERVENTION Two distinct resistive training programs were evaluated on the gastrocnemius: a protocol consisting of concentric contractions only and a mixed concentric/eccentric program. MAIN OUTCOME MEASURES Maximal isometric resistance was measured after each training session. Before and after training, muscle CSA was appreciated using magnetic resonance imaging, whereas changes in muscle pH, phosphorus metabolite ratios, maximal oxidative power (Pmax), and oxidative phosphorylation were studied using 31P nuclear magnetic resonance spectroscopy at rest and during an incremental exercise protocol. RESULTS Magnetic resonance imaging revealed a significant increase (7.1%) in the gastrocnemius CSA in the concentric-eccentric group only. The PCr/Pi (8.3 +/- 0.9 vs 10.4 +/- 1.7) and PCr/ATP (3.68 +/- .36 vs 4.07 +/- .27) resting ratios increased significantly (p = .008) after concentric-eccentric resistance training. Pmax was significantly improved in the concentric-eccentric group (7.0 +/- 2.1W vs 8.4 +/- 1.8W: p < .02). This mixed protocol also reduced the incidence of muscular soreness. CONCLUSION The data suggest that the improved oxidative mechanical power output could be due mainly to a greater muscle cross-section in the concentric-eccentric group, with circumstantial evidence suggesting a relatively higher type IIa fiber activity.

Comprehensive cardiac rehabilitation improves the control of dyslipidemia in secondary prevention.

BACKGROUND Secondary prevention is an important goal of cardiac rehabilitation in patients with coronary heart disease (CHD). Dyslipidemia is one of the major risk factors that is important to control to reduce the incidence of future ischemic coronary events. The aim of the present study was to assess whether control of dyslipidemia, in secondary prevention, could be improved by a comprehensive cardiac rehabilitation program. METHODS Fifty-two newly diagnosed hyperlipidemic men, who had experienced a recent CHD event, were separated in two equal groups of 26 patients: group CR+, in which patients were included in a 2-month cardiac rehabilitation program including an extensive educational program on cardiovascular risk factors, lipids, and diet, and group CR-without any cardiac rehabilitation. Mean age, body mass index, initial levels of total cholesterol, triglycerides, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, and LDL/HDL ratio were not significantly different between the 2 groups. In both groups, each patient was referred to a dietitian and to the same lipidologist to start an appropriate hypolipidemic treatment. Treatment of coronary event, type of hyperlipidemia, and hypolipidemic treatment were not different between the two groups. RESULTS Lipid measurements, performed 3 months after the beginning of the hypolipidemic treatment, showed that patients from the CR+ group, compared with those from the CR-group, had a significantly greater reduction of total cholesterol (23% versus 13%; P < 0.001), of LDL cholesterol (28% versus 12%; P < 0.001), of LDL/HDL ratio (34% versus 13%; P < 0.01) and of triglycerides (33% versus 21%; P = 0.05). CONCLUSIONS Patients with CHD included in a comprehensive cardiac rehabilitation program showed a significantly better response to the hypolipidemic treatment than patients without cardiac rehabilitation. These results could be attributable to the extensive educational program on secondary prevention performed during cardiac rehabilitation, leading to optimized knowledge on lipid-lowering diet and to improved diet and drug adherence. A secondary prevention educational program must be an important part of any comprehensive cardiac rehabilitation program in patients with CHD.