It is hard to say from what information you gave. Heart Failure
is kind of a generic term that could cover a lot of areas. Myocardial infarction
is the blockage of the coronary arteries. When this happens a part of the heart muscle dies. This makes the heart less and less able to pump blood. A valve defect is caused by certain blood bacterial infections, which can cause an otherwise healthy heart not to be able to pump blood in the right direction. This can be catastrophic if it is bad enough. Congestive Heart failure is caused by fluid accumulation in the lungs which makes the heart work very hard to pump blood through it or to get oxygen
to the blood.
I would ask the doctor for clarification if possible.