Effects Of Inspiratory Muscle Training By Fast Absorption And Slow Breathing On Exercise Endurance In Patients With Chronic Heart Failure

BackgroudChronic heart failure(CHF) is the terminal stage of most cardiovascular disease, which is the main cause ofdeath. Because of the reduced exercise endurance, symptoms of dyspnea,most of the CHF patients have to go to see doctors, which is often associated with the impaired systemic muscle function in the process of the disease and limited ventilation disorder caused by physical activity.According to statistics, 30% to 50% of patients with CHFwere inspiratory muscle weakness. The deteriorating of inspiratory muscle strength of CHF patients is a key factor forthe falling of exercise endurance and prognosis.Therefore, maintaining the inspiration function work well is quite important in the process of breathing in patients with CHF. Sotaking timely intervention for inspiratory muscle training in a specific phase is particularly important.At present, more and more foreign literature studies had explored the role of inspiratory muscle training in patients with CHF. Most studies reported that the inspiratory muscle training improved the symptoms of dyspnea, exercise endurance and the heart functional status. However,most of these studies use threshold breathing training apparatus, whichwere not suitable for patients to train at home, to quantitativedata, to insist for a long time.In addition, the domestic research is relatively limited, and they just focused on ways changes of breath training, such as abdominal breathing, deep breathing, lip breathing or by a combination of several ways.A little research have taken attention tothe respiratory muscle training, abdominal breathing in patients with dyspneais difficult to be implemented, if patients trained in a worry way, they were easily fatigue. While shrinkage lip breathing is hard to quantify and isnot easy to master by patients. According to the characteristics of the patients with CHF physiological changes, the object of this study is to improve and apply an inspiratory muscle training by fast absorption(inspiratory muscle) and slowly exhale(prolong exhale, lower lung capacity) in patients with CHF(this method has been confirmed that the effect of COPD) which accord toa study designedfor the patients with stability chronic obstructive pulmonary disease(COPD); and to explore its effect on the CHF patients exercise endurance, the correlation of clinical curative effect, in the process of the training. We hope to provide a long-term, effective and simple family breathing training method and finally improve the quality of life for CHF patients.ObjectiveTo evaluate the effects of inspiratory muscle training by fast absorption and slow breathing on exercise endurance which assessed by 6 minute walk test distance, heart function, resting heart rate, pulmonary function and quality of life in patients with chronic heart failure.Methods1. 100 hospitalized patients with chronic heart failure were collected from the cardiovascular department of the Third Affiliated Hospital of Suzhou University. According to the random number tables, they were randomly divided into the experimental group and control group, 50 cases in each group.2. During hospitalization, both of the experimental group and control group received the same routine treatment, such as prescribed medication, oxygen uptake on demand, health education, etc. In addition, the patients in the experimental group received inspiratory muscle training guided by specially trained nurses. Patients were suggested to do the training exercise in1 to 2 hours after each meal per day, 3 times/day, and 15 min per time. The participants were asked to insist to take inspiratory muscle training exercise after discharged; they should fill in the training diary which the nurse gave. Each of the researchers(total 10 nurses) was responsible for 5 participants. They followed up patients through telephone, every three days before the first two weeks, 1 week each time after 3-6 weeks, 2 weeks each after 7-12 weeks. The nurses should know about the patients’ conditions of breathing training and their experiences on training, whether they felt discomfort when doing the exercise and had some special condition changed. Meanwhile, the nurses should answer the patients or their family members’ questions about the breathing training and gave guidance and supervision to them. The participants insisted on training for 3 months. In the control group, they were followed up through telephone routinely only to ask about their state of disease and medication taking, without guidance for breathing training.3. 6 minute walk test distance, heart function, resting heart rate, quality of life and pulmonary function in hospitalization, after follow-up of 1 month and follow-up of 3 months were measured.Results1. There were no statistically significant differences(P > 0.05) between the experimental group and control group in baseline data such as patients’ age, gender, height, weight, culture degree, occupation, marital status, the course of the disease, medication situation. During the process, 8 cases in the intervention group withdrew and 11 cases withdrew in control group. A total of 81 patients finally completed the experiment, 42 cases in the experimental group and 39 cases in the control group.2. 6 Minute Walk DistanceIn the experimental group, the 6 minute walk distances were significantly improved compared with baseline [(-14.23±19.96) m, P<0.01] at the first month after discharged. After three months of intervention, the 6 minute walk distances were still significantly improved compared with baseline [(-36.69±23.05), P<0.01]. While in the control group, the 6 minute walk distances were significantly improved compared with baseline [(-5.41±10.07) m, P<0.01]at the first month after discharged but they were declined after three months[(3.15±16.64)m, P>0.05]. When compared the first month with the third month, there were statistical difference both in the two groups[the experimental group(-22.45±16.48)m, P<0.01, the control group(8.56±14.09)m, P<0.01]. There was no statistical difference between the two groups in the first month but there was statistical difference between the two groups after the third month.3. Resting Heart RateAfter the first month of intervention, the average of resting heart rate both in the experimental group and the control group was declined compared with their baseline [The experimental group:(8.45±8.76)/min, P<0.01;the control group:(6.18±7.19)/min, P<0.01]. There was no statistical difference between the two groups in the first month. After three months of intervention, the average of resting heart rate both in the experimental group and the control group was still declined compared with the first month[The experimental group:(12.35±9.68)/min, P<0.01;the control group: [(1.82±3.69)/min, P<0.05]. There was statistical difference between the two groups after the third month(P<0.01).4. Heart function gradingAfter the first month of intervention, the heart function of patients both in the experimental group and control group were significantly improved compared with the baseline(P<0.01). When compared the first month with the third month, there was statistical difference only in the experimental group(P<0.05). After the first month of intervention, there was no statistical difference between the experimental group and control group(P>0.05). After three months of intervention, the heart function of patients in the experimental group were improved better than the control group, and there was statistical difference(P<0.01).5. Pulmonary functionAfter the first month of intervention, the indicators of pulmonary function FVC、FEV1、MVV in the experimental group were higher than its baseline, there was statistical difference(P<0.05). The indicators of pulmonary function FVC、FEV1、MVV in the control group were higher than its baseline, but there was no statistical difference(P>0.05). The indicators of pulmonary function FVC、FEV1、MVV in the experimental group improved more than the control group and there was statistical difference between the two groups(P<0.05). After three months of intervention, the indicators of pulmonary function FVC、FEV1、MVV in the experimental group were still higher than its baseline, there was statistical difference(P<0.05). The indicators of pulmonary function FVC、FEV1 in the control group were higher than its baseline, but there was no statistical difference(P>0.05). The indicator of MVV was declined a little than its baseline, there was no statistical difference(P>0.05). When compared the first month with the third month, there were statistical difference of FVC, FEV1, MVV in the experimental group(P<0.05), but only MVV had statistical difference in the control group. The indicators of pulmonary function FVC、FEV1、MVV in the experimental group improved more than the control group and there was statistical difference between the two groups(P<0.01)after three months.6. Quality of life(MLHFQ)After the first month of intervention,in the experimental group,the average score of all the domains of the MLHFQ were significantly declined compared with the baseline(P<0.01); In the control group, the average of total score and emotional field were significantly declined compared with the baseline(P<0.01). There was no statistical difference between the two groups. After three months of intervention, the average score of all the domains of the MLHFQ were still significantly declined compared with the baseline(P<0.01) in the experimental group, but there was no statistical difference in the control group compared with the baseline(P>0.05). When compared the first month with the third month, there was statistical difference of the physical field, emotional field and the total score in the experimental group(P<0.01), and there was statistical difference of the physical field and the total score in the control group. There was statistical difference between the two groups after three months.Conclusion1. Inspiratory muscle training by fast absorption and slow breathing could increase the 6 minute walk distance, decline the rest heart rate and improve the heart function so to enhance the exercise tolerance and quality of life of the patients with chronic heart failure.2. Inspiratory muscle training by fast absorption and slow breathing could be a safe and effective auxiliary rehabilitation treatment for chronic heart failure patients.