@article {Borghi-Silva4705, author = {Audrey Borghi-Silva and Claudia Carrascossa and Cristino Oliveira and Adriano Barroco and Danilo Berton and Debora Villa{\c c}a and Edgar Lira-Filho and Dirceu R. de Almeida and Luis Eduardo Nery and Jos{\'e} Alberto Neder}, title = {Effects of proportional assist ventilation on skeletal muscle reoxygenation after high-intensity exercise in chronic heart failure}, volume = {40}, number = {Suppl 56}, elocation-id = {4705}, year = {2012}, publisher = {European Respiratory Society}, abstract = {Background: Respiratory muscle unloading can enhance the haemodynamic responses to exercise thereby allowing a closer matching between skeletal muscle O2 delivery and utilization in patients with chronic heart failure (CHF). Objective: To assess whether proportional assist ventilation (PAV), compared to sham ventilation, would improve the dynamic coupling between microvascular O2 delivery and O2 uptake (V{\textasciiacute}O2) during recovery from heavy-intensity exercise in patients with CHF. Methods- Twelve patients with CHF (NYHA class II and III and left ventricle ejection fraction= 26{\textpm}9\%) underwent two high-intensity, constant-work rate (80\% peak) cycle ergometer tests receiving PAV or sham ventilation. Off-exercise kinetics of the {\textquotedblleft}primary{\textquotedblright} component of V{\textasciiacute}O2, an index of fractional O2 extraction by near infrared spectroscopy (\~{}Δ[deoxy-Hb+Mb]) in the vastus lateralis) and cardiac output (QT) by impedance cardiography were assessed. Results: PAV speeded the recovery kinetics of all variables compared to sham ventilation.View this table:Table 1: Kinetic parameters for sham and PAV ventilation.Conclusions: These data indicate that PAV has beneficial effects on recovery of muscle metabolism and central haemodynamics after high-intensity exercise in CHF patients.Financial Support: FAPESP.}, issn = {0903-1936}, URL = {https://erj.ersjournals.com/content/40/Suppl_56/4705}, eprint = {https://erj.ersjournals.com/content/40/Suppl_56/4705.full.pdf}, journal = {European Respiratory Journal} }