Kazuto Omiya

Effect of the self-monitoring approach on exercise maintenance during cardiac rehabilitation: a randomized, controlled trial.

Izawa KP, Watanabe S, Omiya K, Hirano Y, Oka K, Osada N, Iijima S: Effect of the self-monitoring approach on exercise maintenance during cardiac rehabilitation: A randomized, controlled trial. Am J Phys Med Rehabil 2005;84:313–321. Objective:To evaluate the effect of the self-monitoring approach (SMA) on self-efficacy for physical activity (SEPA), exercise maintenance, and objective physical activity level over a 6-mo period after a supervised 6-mo cardiac rehabilitation (CR) program. Design:We conducted a randomized, controlled trial with 45 myocardial infarction patients (38 men, seven women; mean age, 64.2 yrs) recruited after completion of an acute-phase, exercise-based CR program. Patients were randomly assigned to an SMA group (n = 24) or control group (n = 21). Along with CR, the subjects in the SMA group self-monitored their weight and physical activity for 6 mos. The SMA used in this study was based on Bandura’s self-efficacy theory and was designed to enhance confidence for exercise maintenance. The control group participated in CR only. All patients were evaluated with the SEPA assessment tool. Exercise maintenance, SEPA scores, and objective physical activity (average steps per week) as a caloric expenditure were assessed at baseline and during a 6-mo period after the supervised CR program. Results:Mean period from myocardial infarction onset did not differ significantly between the SMA and control groups (12.1 ± 1.3 vs. 12.2 ± 1.2 mos, P = 0.692). All patients maintained their exercise routine in the SMA group. Mean SEPA score (90.5 vs. 72.7 points, P < 0.001) and mean objective physical activity (10,458.7 vs. 6922.5 steps/wk, P < 0.001) at 12 mos after myocardial infarction onset were significantly higher in the SMA than control group. SEPA showed significant positive correlation with objective physical activity (r = 0.642, P < 0.001). Conclusions:SMA during supervised CR may effectively increase exercise maintenance, SEPA, and objective physical activity at 12 mos after myocardial infarction onset.

Long-term exercise maintenance, physical activity, and health-related quality of life after cardiac rehabilitation

Izawa KP, Yamada S, Oka K, Watanabe S, Omiya K, Iijima S, Hirano Y, Kobayashi T, Kasahara Y, Samejima H, Osada N: Long-term exercise maintenance, physical activity, and health-related quality of life after cardiac rehabilitation. Am J Phys Med Rehabil 2004;83:884–892. Objective:The purpose of this study was to determine exercise maintenance rate, leisure-time objective physical activity level, and health-related quality of life in relation to exercise maintenance over the 6-mo period after a supervised 5-mo recovery-phase cardiac rehabilitation program in acute myocardial infarction patients. The study also investigated whether exercise maintenance resulted in reproducible health-related quality-of-life outcomes comparable with those of the Japanese normal population. Design:This observational study comprised 109 acute myocardial infarction patients (89 men, 20 women; mean age, 63.5 ± 10.1 yrs). Physiologic outcomes (peak oxygen uptake, handgrip, and knee-extension strength) measured at 1 and 6 mos after acute myocardial infarction onset were compared. Completed exercise maintenance and health-related quality-of-life questionnaires and results of electronic pedometer recordings to evaluate leisure-time objective physical activity level were assessed 6 mos after cardiac rehabilitation. Results:The mean period from acute myocardial infarction to evaluation of outcomes was 18.8 ± 3.4 mos. Ninety of 109 patients (82.6%) continued exercise for >6 mos after cardiac rehabilitation (exercise group); 19 patients (17.4%) quit exercise after cardiac rehabilitation (nonexercise group). Improvement in physiologic outcomes was noted at 6 mos vs. those at 1 mo, but outcomes were not significantly different between groups. The exercise group performed significantly better than the nonexercise group for leisure-time objective physical activity level and scored significantly higher than the nonexercise group for seven of eight health-related quality of life measures, attaining scores similar to those of the Japanese normal population. Conclusions:At >18 mos after acute myocardial infarction, the exercise maintenance rate in our patients remains high, and exercise maintenance may be one of the factors contributing to improvement of health-related quality of life and leisure-time objective physical activity level.

Handgrip strength as a predictor of prognosis in Japanese patients with congestive heart failure.

Background Whether upper-extremity and lower-extremity muscle strength can predict a prognosis of congestive heart failure (CHF) patients is unclear. This study evaluated the impact of muscle strength on long-term mortality in patients with CHF. Design Prospective observational study of male Japanese CHF patients. Methods Clinical characteristics (age, body mass index, left ventricular ejection fraction, heart failure etiology, and medications) were obtained from hospital records of 148 male outpatients with stable CHF. Brain natriuretic peptide was determined as an index of disease severity. Peak oxygen uptake ( V . O 2 ), handgrip, and knee extensor muscle strength were also determined. Results After 1331.9 ± 700.3 days of follow-up, 13 cardiovascular-related deaths occurred, and the patients were divided into two groups: survival (n = 135) and nonsurvival (n = 13). No significant differences were found between the groups in clinical characteristics, brain natriuretic peptide levels, and knee extensor muscle strength. Peak ( V . O 2 ) (P = 0.011) and handgrip strength (P = 0.008) were significantly lower in the nonsurvival versus survival group. Left ventricular ejection fraction, peak ( V . O 2 ), and handgrip strength were found by univariate Cox proportional hazards analysis to be significant prognostic indexes of survival. Multivariate analysis, however, revealed handgrip strength to be an independent predictor of prognosis. A handgrip strength cutoff value of 32.2 kgf was determined by the analysis of receiver-operating characteristics and was assessed. Kaplan-Meier survival curves after log-rank test showed significant prognostic difference between the two groups (P = 0.008). Conclusion Handgrip strength may be useful for forecasting prognosis in patients with CHF. Eur J Cardiovasc Prev Rehabil 16:21-27

Heart rate and blood pressure response to ramp exercise and exercise capacity in relation to age, gender, and mode of exercise in a healthy population.

BACKGROUND The responses of heart rate (HR) and blood pressure to the ramp exercise test are not known and the current understanding of peak oxygen uptake and anaerobic threshold (AT) values in the normal Japanese population is insufficient. METHODS AND RESULTS A total of 749 healthy Japanese subjects aged 20-78 years underwent a cardiopulmonary exercise test using a cycle ergometer or treadmill ergometer with ramp protocols. HR, systolic blood pressure (SBP), and oxygen uptake VO2 at rest, at AT, and at peak exercise were determined. HR and SBP at peak exercise in a cycle ergometer and treadmill ergometer test decreased with age. Work rate at peak exercise in a cycle ergometer increased with body weight and decreased with age. VO2 at AT and at peak exercise were higher in treadmill ergometer testing than in cycle ergometer testing, and were not affected by exercise protocol. Both of these decreased with age. CONCLUSIONS The normal responses of HR and SBP to ramp exercise testing are reported for the first time. AT, peak VO2, and VO2 at each stage are shown for a healthy population. Some of these parameters were influenced by weight, gender, and age, as well as mode of exercise and the protocol used. These results provide useful reference values for interpreting the results of cardiopulmonary exercise testing.

Muscle strength in relation to disease severity in patients with congestive heart failure.

Izawa KP, Watanabe S, Yokoyama H, Hiraki K, Morio Y, Oka K, Osada N, Omiya K: Muscle strength in relation to disease severity in patients with congestive heart failure. Am J Phys Med Rehabil 2007;86:893–900. Objective:Indices of exercise capacity such as peak oxygen uptake (&OV0312;O2peak) and muscle strength are important in association with reduced mortality. The present study compared differences in &OV0312;O2peak and muscle strength indices (grip strength and knee extensor and flexor muscle strength) with disease severity and investigated the relation of these variables in congestive heart failure (CHF) patients. Design:The study comprised 102 patients with stable CHF (93 men, age 61.4 ± 10.2 yrs) with left ventricular ejection fraction (LVEF) <40% by echocardiography. We used New York Heart Association (NYHA) functional class to index disease severity. &OV0312;O2peak, grip strength, knee extensor, and flexor muscle strength were determined. Patients were divided into three groups by NYHA class: class I (n = 39), class II (n = 49), and class III (n = 14). Results:Age, sex, and LVEF did not differ according to NYHA class. &OV0312;O2peak and all muscle strength indices decreased with increases in NYHA class (P < 0.05). &OV0312;O2peak correlated positively with all muscle strengths (P < 0.05). Stepwise linear regression analysis revealed that grip and knee extensor strength were important in predicting &OV0312;O2peak. Conclusions:Exercise capacity and disease severity in CHF patients may be influenced not only by lower-limb but also upper-limb muscle strength.

Three-dimensional echocardiographic assessments of exercise-induced changes in left ventricular shape and dyssynchrony in patients with dynamic functional mitral regurgitation

AIMS Left ventricular (LV) shape and LV dyssynchrony are two cofactors associated with functional mitral regurgitation (MR) in patients with heart failure. Both can be accurately examined by real-time three-dimensional echocardiography (3DE). We examined the relationship between dynamic MR and exercise-induced changes in LV shape and synchronicity using 3DE. METHODS AND RESULTS Fifty patients with systolic LV dysfunction underwent 2D and 3D quantitative assessment of LV function, shape, and synchronicity at rest and during symptom-limited exercise test. According to the magnitude of change in MR, patients were divided into EMR group (15 patients, 30%), if the degree of MR increased during test, and NEMR group. During exercise, the changes in LV volumes and ejection fraction were similar in both groups, whereas changes in mitral valvular deformation parameters, in LV sphericity index, and in the extent of LV dyssynchrony were more pronounced in the EMR group. At rest, only the 3D sphericity index could distinguish the two groups. By stepwise multiple regression model, dynamic changes in the systolic dyssynchrony index, sphericity index, and coaptation distance were associated with dynamic MR (r(2) = 0.45, P = 0.012). CONCLUSION Dynamic MR during exercise is related to the 3D changes in LV shape and in LV synchronicity.

Changes in mitral regurgitation and left ventricular geometry during exercise affect exercise capacity in patients with systolic heart failure.

AIMS exercise may dramatically change the extent of functional mitral regurgitation (MR) and left ventricular (LV) geometry in patients with chronic heart failure (CHF). We hypothesized that dynamic changes in MR and LV geometry would affect exercise capacity. METHODS AND RESULTS this study included 30 CHF patients with functional MR who underwent symptom-limited bicycle exercise stress echocardiography and cardiopulmonary exercise testing for quantitative assessment of MR (effective regurgitant orifice; ERO), and pulmonary artery systolic pressure (PASP). LV sphericity index was obtained from real-time three-dimensional echocardiograms. The patients were stratified into exercised-induced MR (EMR; n = 10, an increase in ERO by ≥13 mm(2)) or non-EMR (NEMR; n = 20, an increase in ERO by <13 mm(2)) group. At rest, no differences in LV volume and function, ERO, and PASP were found between the two groups. At peak exercise, PASP and sphericity index were significantly greater (all P < 0.01) in the EMR group. The EMR group revealed lower peak oxygen uptake (peak VO(2); P = 0.018) and greater minute ventilation/carbon dioxide production slope (VE/VCO(2) slope; P = 0.042) than the NEMR group. Peak VO(2) negatively correlated with changes in ERO (r = -0.628) and LV sphericity index (r = -0.437); meanwhile, VE/VCO(2) slope was well correlated with these changes (r = 0.414 and 0.364, respectively). A multivariate analysis identified that the change in ERO was the strongest predictor of peak VO(2) (P = 0.001). CONCLUSION dynamic changes in MR and LV geometry contributed to the limitation of exercise capacity in patients with CHF.

GENDER-RELATED DIFFERENCES IN CLINICAL CHARACTERISTICS AND PHYSIOLOGICAL AND PSYCHOSOCIAL OUTCOMES OF JAPANESE PATIENTS AT ENTRY INTO PHASE II CARDIAC REHABILITATION

OBJECTIVE To examine gender differences in clinical characteristics and physiological and psychosocial outcomes at entry into phase II cardiac rehabilitation. DESIGN Cross-sectional study. SUBJECTS The study comprised 442 consecutive patients with cardiac diseases assessed at entry into a phase II cardiac rehabilitation programme. METHODS Clinical characteristics of the patients, such as age, education, marital status, employment and body mass index, were obtained from hospital records. Oxygen uptake, handgrip and knee extensor muscle strength were measured to assess physiological outcomes. Self-efficacy for physical activity, hospital anxiety depression scale and health-related quality of life assessed by Short Form-36 were evaluated to assess psychosocial outcomes. RESULTS The number of married women and their levels of education, employment and body mass index were significantly lower, and their ages higher, than those of the men. Measures of physiological outcome in women were significantly lower than those in men. Measures of self-efficacy for physical activity and Short Form-36 physical and emotional subscale scores were lower and anxiety levels higher in women than in men. CONCLUSION Cardiac rehabilitation programmes exclusively for women focusing on physiological outcomes, group counselling, and training to enhance physical and emotional domains may encourage increased participation by women in cardiac rehabilitation.

The exercise training effects of skeletal muscle strength and muscle volume to improve functional capacity in patients with myocardial infarction

BACKGROUND No previous studies have fully investigated the exercise training effect on the skeletal muscle strength and volume to improve the exercise capacity in patients with myocardial infarction (MI). The present study was performed based on a hypothesis that the relationship between exercise capacity, skeletal muscle strength and volume might be changed by the amount of skeletal muscle volume in MI patients up to 3 months after the onset. METHODS Seventy patients with MI underwent symptom-limited cardiopulmonary exercise testing using a treadmill. The lower limb muscle volume (MV) was evaluated according to electrical impedance analysis and the maximal knee extension strength (Peak torque: PT) was measured by a Biodex. All patients participated in 12-week exercise training program. The subjects were divided into 2 groups on the basis of MV: Group H, MV>==22 kg; Group L, MV<22 kg. Delta values were calculated as follows: the value at 3 months minus the value at 1 month. RESULTS A positive and significant correlation was observed between the delta PT and delta peak VO(2) (r=0.50, p<0.005) only in the L group. No significant correlation was observed between the delta peak VO(2) and the delta lower limb MV or between the delta lower limb MV and the delta PT in the 2 groups. CONCLUSIONS Cardiac rehabilitation program combined with resistance and aerobic training improved exercise capacity and increased not the skeletal muscle volume but the skeletal muscle strength in patients with MI in their recovery phase. It was presumed that the improvement of exercise capacity was determined by the skeletal muscle strength not by the muscle volume especially in MI patients with low muscle volume.

Age-related differences in physiologic and psychosocial outcomes after cardiac rehabilitation.

Izawa KP, Watanabe S, Oka K, Hiraki K, Morio Y, Kasahara Y, Osada N, Omiya K, Iijima S: Age-related differences in physiologic and psychosocial outcomes after cardiac rehabilitation. Objective:To examine differences in physiologic and psychosocial outcomes between age groups after an exercise-based supervised-recovery phase II cardiac rehabilitation outpatient program. Design:This is a longitudinal observational study. The study assessed 442 consecutive cardiac patients. Patients were divided into the middle-aged group (<65 yrs, n = 242) and older-age group (≥65 yrs, n = 200). Peak oxygen uptake, handgrip and knee extensor muscle strength, upper- and lower-body self-efficacy for physical activity, and physical component summary and mental component summary scores as assessed by SF-36 were measured at 1 and 3 mos after the onset of acute myocardial infarction or cardiac surgery and were compared. Results:All physiologic and psychosocial outcomes increased significantly between months 1 and 3 in both groups. However, increases were greater in the middle-aged vs. older-aged group in peak oxygen uptake (+13.1% vs. +8.7%, P < 0.01), knee extensor muscle strength (+17.6% vs. +13.3%, P = 0.01), lower-body self-efficacy for physical activity (+17.3% vs. +12.7%, P = 0.02), and physical component summary score (+5.4% vs. +2.7%, P = 0.02). Conclusions:Age-related differences in various physiologic and psychosocial measures indicated greater improvement from an exercise-based supervised recovery-phase II cardiac rehabilitation outpatient program in middle-aged vs. older-aged patients. Older adults may derive equal mental or emotional benefit from such a cardiac rehabilitation program but do not experience as much improvement in physiologic outcomes as middle-aged adults.