Inspiratory Muscle Training in Stroke Patients With Stable Congestive Heart Failure: a Prospective Randomized Controlled Trial.

A total of forty stroke patients with stable CHF, NYHA (New York Heart Association) class I-III, aging between 20 to 85 year-old, will be eligible and randomly assigned into IMT and control group. The diagnosis of CHF is according to framingham Criteria. Consensus will be completed before our intervention. All technicians who performed the different measurements and assessed the outcomes were blinded to group assignments.

Both of groups will receive a conventional stroke rehabilitation program. Exclusion criteria Patients who can't tightly place their lips over the mouthpiece or have air leakage during inhaling or exhaling through the threshold device, have COPD, a history of recent exacerbation, unstable angina, decompensated CHF, complicated arrhythmias, at risk or history of pneumothorax, large bullae on chest radiograph, marked osteoporosis together with a history of spontaneous rib fractures, a history of recent lung surgery (ie, within 12 months), or use of long-term oxygen therapy.

The Institutional Review Board of Chang Gung Memorial Hospital, Kaohsiung Medical Center will approve the study protocol and all patients provided informed consent.

IMT training: Inspiratory muscle training will be performed by using a pressure threshold device (Threshold® IMT HS730, RESPIRONICS Inc, Cedar Grove, NJ, USA). During training, patients will be in a sitting position with a nose-clip and instructed to place their lips around the mouthpiece, inhale with enough force to open the valve, exhale through the mouthpiece, and then continue inhaling and exhaling without removing the device from their mouth. During the initial training session, patients will be encouraged to start at a resistance equal to 30% of their MIP or at a load the patient can tolerated, and then the loading will be gradually increased 2cm H2O per week or as symptom tolerated and according to the RPE scale. Throughout the first session training, the monitoring of oxygen saturation will be applied. And the load will be minimized if there is any decrease in oxygen saturation during loaded breathing Patients will take intermittent periods of rest if they feel uncomfortable; and if the patient cannot tolerate the increased resistance or the patients who are unable to finish full session training, and then those of last part of training will be continued. Patients will be warned to expect transient delayed-onset muscle soreness, a consequence of muscle adaptation to an unaccustomed activity. And training will be immediately stopped if they experience severe sharp pain on inspiration.

Patient will be trained daily, total 30 minutes or 15 minutes twice per day, at least 5 times a week, for 4 weeks; then readmitted to hospital 2 weeks later . For checking the compliance of IMT at home, patients will be monitored by making a phone call to them twice a week. Or patient will receive an outpatient program about 10 weeks if they are not readmitted to our hospital, or patient will directly receive outpatient program if they cannot be admitted in the hospital..