What are the 4 stages of congestive heart failure?

Four stages of congestive heart failure are Stage A, B, C, D. Stage A and B are pre heart failure stages when persons do not have symptoms but have predilection to heart failure such as Diabetes, Hypertension, obesity, alcohol abuse, heart blocks and family history of heart failure. Stage C is when persons have symptoms, diagnosed with heart failure and responding to treatment. Stage D is when persons have advanced symptoms that may not get better with treatment.