Did they indicate if any permanent tissue damage had occurred during the heart attack?
If they believe the damage is reversible, then over time the muscle will recover and improve output from the left ventricle. If dilation has occurred through overworking of the left ventricle, trying to compensate, then it will take a little longer.
What are the pressures in the left ventricle from the echo report? Usually there are two, one when it reaches the same pressure as the left atrium closing the valve and one when it reaches its peak for pushing against the pressure in the aorta.
Ed is exactly correct, but I question the comment it will take longer if the heart is dilated.
My heart reversed remodeling quickly. The remodeling (enlarged left ventricle) was due to inhalation of fumes and dust from a toxic environment that triggered the heart failure (diagnosed as having had a heart attack). I believe heart chamber dilatation can happen very quickly, and can return quickly with proper treatment.
An EF 33% after heart attack indicates your husband's heart function was/is not in the red zone of 29% or less that would cause heart failure. Heart failure can lead to congested lungs (edema) and effect normal breathing and possibly chest pain (angina). More than 6 years ago, I was in ICU with congested heart failure following a prior heart attack. With medication and a stent my heart returned to normal size and EF is now 59%.
If your husband's health history includes an enlarged heart which is the most likely scenario, the enlarged heart reduces the heart's contractility and the lower EF, and based on the medication your doctor has prescribed, it appears your doctor concludes your husband has an ischemic (lack of blood flow) underpinning for weaker than normal EF. Increase the perfusion of a good blood supply from stents and medication can return the heart function to normal.
As ed asks, has the test indicated any necrotic (dead) heart cells. If so, there may be permanent damage. Frequently, the heart cells are stunned and that would cause the low EF, and stunned cells sometimes recover...that has been my experience.
Thanks for sharing, and if you have any followup questions you are welcome to respond. Take care.