Welcome to HCM,
After going through your history effect of anaemia
on heart depends on severity of anaemia and duration of the disease.In other words it depends on cause if it can be removed and iron can be replenished.
If your anaemia is due to low iron level and if you take treatment your haemoglobin
will improve very fast provided there is no other cause so your heart will not be affected.Once you start feeling better you can start light exercise with out going breathless.
In the mean time take care of your diet and medicine like Iron and vitamin supplements.
If it is only iron deficiency
rapid correction of iron can be done with injectable forms giving IV.
Even if it is appropriate a Blood transfusion
may be given in consultation of physician which will correct anaemia and will give you iron for stores also.
Please take care of yourself.