What are the 4 stages of congestive heart failure?

Stage 1-Ordinary physical activity does not cause dyspnea ,fatigue and palpitations . Stage 2-comfortable at rest but ordinary physical activity cause dyspnea ,fatigue and palpitations . stage 3-comfortable at rest ,less than ordinary physical activity cause dyspnea ,fatigue and palpitations . Stage 4-uncomfortable at rest ,unable to carry out any physical activity without discomfort .