cardiomegaly causes

  On a recent echo my doctor discovered I had slight enlargment of the heart muscle
  (cardiomegaly).  I am about 70 lbs. overweight.  He wants me to lose weight to
  see if the extra weight caused the heart to enlarge before he diagnoses any
  kind of cardiomyopathy.  He also told me to avoid strenuous exercise.  I got a
  respiratory virus about 4 or 5 years ago and was hospitalized for a week.  During
  that time I was given large doses of steroids and antibiotics.  I also had
  an episode of attrial fibrillation which was caught by the doctor and had an
  echo done at that time (my first).  It showed mitral valve prolapse.  I also have
  an irregular heartbeat.  I think the steroids aggravate it (my opinion).  Ever since
  that time, I have had asthma and have had 2 other hospitalizations.  I can't find
  anything on the Internet to indicate that being 70 lbs. overweight can cause
  cardiomegaly.  I'm really rather worried that this might be cardiomyopathy, especially
  since heart disease runs in my family (grandparents and others).  Any information
  you can offer would be so appreciated.
Dear Cheryl
A slight degree of heart enlargement can be seen in obese patients, especially when there is concomitant high blood pressure. The more important concern is whether the heart pumping function is abnormal - this is more of a determinant in whether you have a cardiomyopathy.
You certainly could have asthma. You should be aware, though, that heart failure can sometimes masquerade as asthma. A good echocardiogram would resolve this situation.
I hope this has been useful. I wish you the best of luck.
If you would like to make an appointment at the Cleveland Clinic Heart Center, please call 1-800-CCF-CARE or inquire online by using the Heart Center website at www.ccf.org/heartcenter.   The Heart Center website contains a directory of the cardiology staff that can be used to select the physician best suited to address your cardiac problem.