Welcome to health care magic forum..
There are various causes which can lead to increase in the size of your heart such as
normally though aerobic exercise
and strength training, Pathologically hypertension, cardiovascular diseases, chronic obstructive pulmonary disease
, cardiac fibrosis, connective tissue
disorders can lead to increase in size of your heart..So Based on the type on disease which has lead to increase in the size of heart various treatment modalities are available. I would advice you to consult a cardiologist
and discuss the further management of your condition.
Hope this helps..