Maria Bäck

Effects of High Frequency Exercise in Patients before and after Elective Percutaneous Coronary Intervention

Background: The aim of this study was to evaluate the effects of high frequency exercise for patients before and after an elective percutaneous coronary intervention (PCI), with special reference to maximal aerobic capacity, muscle function, health related quality of life (HRQoL), waist–hip ratio (WHR) and restenosis. Methods: A randomised, controlled study was performed in Sweden between 2004 and 2006 in thirty-seven patients (five women) with stable coronary artery disease (CAD), age 63.6 ± 6.9 years, randomised to either high frequency exercise or control group. The patients in the training group performed three endurance resistance exercises and trained on a cycle ergometer 30 min, 5 times a week for 8 months at 70% of VO2max. Results: Patients in the training group significantly improved their maximal aerobic capacity (15 (9–46) vs. 8 (0–18)% p ≤ 0.05), shoulder flexion (p ≤ 0.01), shoulder abduction (p ≤ 0.01) and heel-lift (p ≤ 0.05) compared to the control group. There were no significant differences between the groups in HRQoL, WHR and restenosis. Conclusion: High frequency exercise in patients treated with PCI seems to improve maximal aerobic capacity and muscle function, which may reduce the risks of further progression of atherosclerosis. However, further larger studies are needed to fully investigate the effects of exercise in patients with PCI.

The impact on kinesiophobia (fear of movement) by clinical variables for patients with coronary artery disease.

BACKGROUND The impact on kinesiophobia (fear of movement) for patients with coronary artery disease (CAD) is not known. The aims were to describe the occurrence of kinesiophobia in patients with CAD, and to investigate the influence on kinesiophobia by clinical variables. MATERIALS AND METHODS In total, 332 patients, mean age, 65 ± 9.1 years diagnosed with CAD at a university hospital were included in the study. The Tampa Scale for Kinesiophobia Heart (TSK-SV Heart) was used to assess kinesiophobia. Comparisons between high versus low levels of kinesiophobia were measured for each variable. Binary logistic regression analyses were performed with a high level of kinesiophobia (TSK-SV Heart>37) as dependent variable, and with the observed variables as independent. The study had an exploratory, cross-sectional design. RESULTS A high level of kinesiophobia was found in 20% of the patients. The following variables decreased the odds ratio (OR) for a high level of kinesiophobia: Attending cardiac rehabilitation (yes vs no: -56.7%), level of physical activity (medium vs high: -80.8%), Short-Form 36: general health (-4.3%), physical functioning (-1.8%). Two variables increased the OR for a high level of kinesiophobia: heart failure as complication at hospital (yes vs no: 418.7%), anxiety (19.2%). Previous heart failure (yes vs no) was unexpectedly found to reduce kinesiophobia (-88.3%) due to suppression. CONCLUSIONS Several important clinical findings with impact on rehabilitation and prognosis for patients with CAD were found to be associated with a high level of kinesiophobia. Therefore, kinesiophobia needs to be considered in secondary prevention for patients with CAD.

Increasing exercise capacity and quality of life of patients with heart failure through Wii gaming : The rationale, design and methodology of the HF-Wii study; A multicentre randomized controlled trial

Exercise is known to be beneficial for patients with heart failure (HF), and these patients should therefore be routinely advised to exercise and to be or to become physically active. Despite the beneficial effects of exercise such as improved functional capacity and favourable clinical outcomes, the level of daily physical activity in most patients with HF is low. Exergaming may be a promising new approach to increase the physical activity of patients with HF at home. The aim of this study is to determine the effectiveness of the structured introduction and access to a Wii game computer in patients with HF to improve exercise capacity and level of daily physical activity, to decrease healthcare resource use, and to improve self‐care and health‐related quality of life.

Validation of a questionnaire to detect kinesiophobia (fear of movement) in patients with coronary artery disease.

OBJECTIVE To investigate the validity and reliability of the Tampa Scale for Kinesiophobia Heart (TSK-SV Heart), a brief questionnaire to detect kinesiophobia (fear of movement) in patients with coronary artery disease. DESIGN Methodological research (cross-sectional study). SUBJECTS A total of 332 patients, mean age 65 years (standard deviation 9.1) diagnosed with coronary artery disease at a university hospital were included in the study. METHODS The psychometric properties of the TSK-SV Heart were tested. The tests of validity comprised face, content, and construct validity. The reliability tests included composite reliability, internal consistency and stability over time. RESULTS In terms of reliability, the TSK-SV Heart was found to be stable over time (intra-class correlation coefficient 0.83) and internally consistent (Cronbachs alpha 0.78). Confirmatory factor analysis provided acceptable fit for a hypothesized 4-factor model with inclusion of a method factor. CONCLUSION These results provide support for the reliability of the TSK-SV Heart. The questionnaire appears to be valid for use in patients with coronary artery disease. However, some items require further investigation due to low influence on some sub-dimensions of the test. The sub-dimensions of kinesiophobia require future research concerning their implications for the target group.

Secondary prevention in coronary artery disease. Achieved goals and possibilities for improvements

AIM To describe presence of risk indicators of recurrence 6 months after hospitalisation due to coronary artery disease at a university clinic. METHODS The presence of risk indicators, including tobacco use, lipid levels, blood pressure and glucometabolic status, including 24-hour blood pressure monitoring and an oral glucose-tolerance test, was analysed. RESULTS Of 1465 patients who were screened, 402 took part in the survey (50% previous myocardial infarction and 50% angina pectoris). Mean age was 64 years (range 40-85 years) and 23% were women. Present medications were: lipid lowering drugs (statins; 94%), beta-blockers (85%), aspirin or warfarin (100%) and ACE-inhibitors or angiotensin II blockers (66%). Values above target levels recommended in guidelines were: a) low density lipoprotein (LDL) in 40%; b) mean blood pressure (day or night) in 38% and c) smoking in 13%. Of all patients, 66% had at least one risk factor (LDL or blood pressure above target levels or current smoking). An abnormal glucose-tolerance test was found in 59% of patients without known diabetes. If no history of diabetes, 85% had either LDL or blood pressure above target levels, current smoking or an abnormal glucose-tolerance test. However, with treatment intensification to patients with elevated risk factors 56% reached target levels for blood pressure and 79% reached target levels for LDL. CONCLUSION Six months after hospitalisation due to coronary artery disease, despite the high use of medication aimed at prophylaxis against recurrence, the majority were either above target levels for LDL or blood pressure or continued to smoke.

Fear-avoidance beliefs and cardiac rehabilitation in patients with first-time myocardial infarction.

OBJECTIVE The aim of this study was to examine fear-avoidance beliefs in patients after first-time myocardial infarction and to determine how such beliefs change over time. A further aim was to analyse fear-avoidance beliefs and physical activity levels in patients attending exercise-based cardiac rehabilitation led by a registered physiotherapist, compared with a control group. DESIGN Prospective cohort study. PATIENTS A total of 62 patients after first-time myocardial infarction were consecutively included in the study, mean age 61 years (range 42-73). Thirty-four patients chose exercise-based cardiac rehabilitation and 28 carried out the exercise regime on their own (controls). At follow-up, 57 patients (n = 30 and n = 27, respectively) responded. METHODS The Fear-Avoidance Beliefs Questionnaire and the Exercise and Physical Activity questionnaires were completed at 1 and 4 months post-infarction. RESULTS Clinically relevant fear-avoidance beliefs were seen in 48% of all patients at baseline, compared with 21% at follow-up (p = 0.01). Corresponding baseline values were 62% for the cardiac rehabilitation group and 29% for controls (p = 0.02). At follow-up, 4 months post-infarction, the difference between the groups was no longer seen. The total amount of physical activity increased over time for the cardiac rehabilitation group (p = 0.03), and this was also significant compared with the control group (p = 0.02). CONCLUSION Compared with controls, patients attending exercise-based cardiac rehabilitation led by a registered physiotherapist, demonstrated higher levels of fear-avoidance beliefs at baseline, which decreased over time. Furthermore, attendees increased their level of physical activity and exercise over time. Participation in exercise-based cardiac rehabilitation is therefore strongly recommended for patients with myocardial infarction, especially for those with increased fear of movement.

Physical activity in relation to cardiac risk markers in secondary prevention of coronary artery disease

BACKGROUND The relationship between physical activity and cardiac risk markers in secondary prevention for patients with coronary artery disease (CAD) is uncertain. The aims of the study were therefore to examine the level of physical activity in patients with CAD, and to investigate the association between physical activity and cardiac risk markers. METHODS In total, 332 patients, mean age, 65 ± 9.1 years, diagnosed with CAD at a university hospital were included in the study 6 months after their cardiac event. Physical activity was measured with a pedometer (steps/day) and two questionnaires. Investigation of cardiac risk markers included serum lipids, oral glucose-tolerance test, twenty-four hour blood pressure and heart rate monitoring, smoking, body-mass index (BMI), waist-hip ratio, and muscle endurance. The study had a cross-sectional design. RESULTS The patients performed a median of 7,027 steps/day. After adjustment for confounders, statistically significant correlations between steps/day and risk markers were found with regard to; high-density lipoprotein cholesterol (HDL-C) (r=0.19, p<0.001), muscle endurance measures (r ranging from 0.19 to 0.25, p=0.001 or less) triglycerides (r=-0.19, p<0.001), glucose-tolerance (r=-0.23, p<0.001), BMI (r=-0.21, p<0.001), 24-h heart rate recording during night (r=-0.17, p=0.004), and average 24-h heart rate (r=-0.13, p=0.02). CONCLUSIONS A relatively high level of physical activity was found among patients with CAD. There was a weak, but significant, association between pedometer steps/day and HDL-C, muscle endurance, triglycerides, glucose-tolerance, BMI and 24-h heart rate, indicating potential positive effects of physical activity on these parameters. However, before clinical implications can be formed, more confirmatory data are needed.

Kinesiophobia mediates the influences on attendance at exercise-based cardiac rehabilitation in patients with coronary artery disease

ABSTRACT Purpose: To identify predictors of attendance at exercise-based cardiac rehabilitation (CR) and to test the hypothesis that kinesiophobia mediates the influence on attendance at CR in patients with coronary artery disease (CAD). Patients: In total, 332 patients (75 women; mean age 65 ± 9.1 years) with a diagnosis of CAD were recruited at Sahlgrenska University Hospital, Sweden.Methods: The patients were tested in terms of objective measurements, self-rated psychological measurements, and level of physical activity. A path model with direct and indirect effects via kinesiophobia was used to predict participation in CR. An exploratory selection of significant predictors was made. Results: A current incidence of coronary bypass grafting (p < 0.001) and a diagnosis of ST-elevation myocardial infarction (p = 0.004) increased the probability of attendance at CR, while kinesiophobia (p = 0.001) reduced attendance. As a mediator, kinesiophobia was influenced by four predictors and the following indirect effects were found. General health and muscle endurance increased the probability of attendance at CR, while self-rated anxiety and current incidence of heart failure had the opposite effect. Conclusions: This study suggests that kinesiophobia has an influence on and a mediating role in attendance at CR. The results need to be further investigated in relation to clinical practice.

High frequency home-based exercise decreases levels of vascular endothelial growth factor in patients with stable angina pectoris.

Background In coronary artery disease (CAD), circulating angiogenic factors have been seen to increase, possibly as a response to ischaemia. Regular physical activity (PA) is recommended for prevention and treatment of CAD, but more research is needed to optimise PA regimes. We investigated the effect of home-based high frequency exercise (HFE) on angiogenic cytokines and cardiac markers in patients with stable CAD. Design This was a randomised case-control study Methods Sixty-two patients, with stable CAD, were randomised to HFE (n = 33), (aerobic exercise 70% of max, 30 min, five times/week and resistance exercise three times/week), performed at home, or usual lifestyle (control, n = 29). After eight weeks, percutaneous coronary intervention (PCI) was performed in both groups, and the HFE group continued another six months of exercise. Serum vascular endothelial growth factor (VEGF) and stromal derived factor-1 (SDF-1), plasma N-terminal-brain natriuretic peptide (NT-proBNP), high-sensitive troponin T (TnT) and copeptin were analysed. Results Data are presented as median (25th, 75th percentile) of relative changes (%) from baseline. Values of p are given for the difference between the HFE and controls. HFE decreased circulating VEGF levels, before PCI (−5% (−15%, −2%)), while VEGF levels increased in the control group (5% (−3%, 20%) p = 0.004). A significant difference in VEGF remained at three months post-PCI (HFE (−1%(−12%, 5%), control (7% (0%, 14%), p = 0.04), but not at six months after PCI. SDF-1, NT-proBNP, TnT and copeptin levels did not differ significantly. In addition, VEGF levels were positively correlated to NT pro-BNP. Conclusions Home-based HFE decreased circulating VEGF in patients with stable CAD, suggesting a reduced ischaemic burden. HFE does not increase markers of cardiac dysfunction, suggesting that it is a safe therapeutic intervention in these patients.

Test–retest reliability and responsiveness to change of clinical tests of physical fitness in patients with acute coronary syndrome included in the SWEDEHEART register:

Background: To maximise the benefits obtainable from exercise-based cardiac rehabilitation, an evaluation of physical fitness using reliable, clinically relevant tests is strongly recommended. Recently, objective tests of physical fitness have been implemented in the SWEDEHEART register. The reliability of these tests has, however, not been examined for patients with acute coronary syndrome. Aims: The aim of this study was to assess the test–retest reliability and responsiveness to change of the symptom-limited bicycle ergometer test, the dynamic unilateral heel-lift test and the unilateral shoulder-flexion test in patients with acute coronary syndrome. Methods: In a longitudinal study design, a total of 40 patients (mean age 63.8 ± 9.5 years, five women), with ACS, aged < 75 years, were included at a university hospital in Sweden. The intra-class correlation coefficient (ICC) with a 95% confidence interval, standard error of measurement (SEM) and responsiveness in terms of the minimal detectable change were calculated. Results: Excellent reliability was found, showing ICC values of 0.98 (0.96–0.99), SEM 4.71 for the bicycle ergometer test, ICC 0.87 (0.75–0.93), SEM 4.62 for the shoulder-flexion test and ICC 0.84 (0.71–0.91), SEM 2.24 for the heel-lift test. The minimal detectable change was 13 W, 13 and 6 repetitions for the bicycle ergometer test, shoulder-flexion and heel-lift tests respectively. Conclusions: The test–retest reliability of clinical tests evaluating physical fitness in patients with acute coronary syndrome included in the SWEDEHEART register was excellent. This makes the future comparison and evaluation of treatment effects in large unselected clinical populations of acute coronary syndrome possible.