Optoelectronic Pletysmography and Diaphragmatic Thickness in Heart Failure Patients

The investigators aimed to evaluate the effects of cardiomegaly associated with inspiratory muscle weakness on tricompartmental distribution of chest wall volumes, on the thickness of the right hemidiaphragm and on the contraction speed of the respiratory muscles. As method of the present research, a pilot cross-sectional study was conducted with fourteen (14) patients with heart failure, functional class II and III, clinically stable, with cardiomegaly. Two groups were formed: one group with inspiratory muscle weakness (WG) (maximal inspiratory pressure - MIP \<70% predicted MIP) and a control group without weakness (CG). The pulmonary and respiratory muscle functions were assessed by spirometry and manometer, respectively. Before and after maximal exercise test, optoelectronic plethysmography was performed to evaluate the distribution of volumes, the kinematics and the contraction speed of chest wall muscles. The high-resolution ultrasonography was also used before and after the maximum test for obtaining diaphragmatic thickness