This project deals with exercise in acute heart failure in three different groups (conventional medical treatment; exercise with non-invasive ventilation and exercise with placebo of non-invasive ventilation).

All of the subjects performed an individualized clinical evaluation right after hospital admission on day 1 (D1) by the cardiologist and physiotherapis involved in the study. Pulmonary function tests (spirometry), blood sample (brain natriuretic peptide [NT-proBNP] and high sensitive C-reactive protein [hs-CRP]), six-minute walk test (6MWT), and maximal inspiratory pressure (MIP) test were performed.

After the clinical tests were performed, the patients were randomized into three groups, and all received standard medical treatment.

The control group (CTL) received medical treatment and did not perform aerobic exercise training; the ET+NIV group performed aerobic exercise training associated with NIV once a day, for 8 consecutive days; and the ET+Sham group performed aerobic exercise with placebo NIV once a day, for 8 consecutive days. The ET+NIV and ET+Sham groups also received medical treatment.

After eight consecutive days, all of the patients underwent a new clinical evaluation (D10). After D10, all of the patients continued to receive only conventional treatment, and they were followed up for main outcomes (hospital discharge, worsening HF, or death). Worsening HF was considered when a patient needed to be transferred to the intensive care unit.

Inclusion Criteria:

• established diagnosis of acute HF; previous Doppler echocardiography with left ventricle ejection fraction (LVEF) <30%, and NYHA Class IV.

Exclusion Criteria:

• unstable angina, complex cardiac arrhythmias, pacemaker, cardiac resynchronization therapy or left ventricle assist device, myocardial infarction within the previous 12 months, oxygen saturation by pulse oximetry (SpO2) at rest < 88% without oxygen supplementation, acute pulmonary edema with clinical indications for mechanical ventilation