title: Inspiratory muscle training in patients with heart failure: meta-analysis of randomized trials.
abstract: Patients with chronic heart failure (CHF) may have lower inspiratory muscle strength and endurance, which may contribute to exercise intolerance. Inspiratory muscle training (IMT) can have beneficial effects on these patients. Thus, the aim of this study was to systematically review the effects of IMT compared to control groups (placebo-IMT or another intervention) in patients with CHF. A search of databases (MEDLINE, Cochrane CENTRAL and PEDro) and references of published studies, from 1960 to 2011, was conducted. Randomized trials comparing IMT to control groups in the treatment of patients with CHF were included. The GRADE approach was used to determine the quality of evidence for each outcome. Of 119 articles identified, 7 studies were included. IMT increased the distance walked in the six-minute walk test [69 m (95% CI: 7.21 to 130.79)] (very low evidence) and maximal static inspiratory pressure [23.36 cmH20 (95% CI: 11.71 to 35.02)] (low evidence) compared to control groups. However, IMT provides a significant improvement in peak oxygen consumption only in the studies that performed IMT for 12 weeks against no inspiratory load in patients with inspiratory muscle weakness [3.02 ml/kg/min-1 (95% CI: 0.43 to 5.61)]. IMT improves functional capacity and inspiratory muscle strength thereby deserving consideration as an additional intervention in patients with CHF. Larger and better-designed studies, however, are needed to clarify the potential benefit of IMT in this patient population.
authors.affiliation: Departamento de Fisioterapia, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS, Brazil. roplentz@yahoo.com.br
authors.forename: Rodrigo Della Méa
authors.initials: RD
authors.lastname: Plentz
authors.forename: Graciele
authors.initials: G
authors.lastname: Sbruzzi
authors.forename: Rodrigo Antonini
authors.initials: RA
authors.lastname: Ribeiro
authors.forename: Janaína Barcellos
authors.initials: JB
authors.lastname: Ferreira
authors.forename: Pedro
authors.initials: P
authors.lastname: Dal Lago
mesh_terms: D001945:Breathing Exercises; D005080:Exercise Test; D006333:Heart Failure / Q000628:therapy*; D006801:Humans; D053580:Muscle Strength / Q000502:physiology; D010101:Oxygen Consumption / Q000502:physiology; D016032:Randomized Controlled Trials as Topic; D012132:Respiratory Muscles / Q000503:physiopathology