I always thought having a "big heart" was a good thing!

It would depend on which "side" the heart was swelling and if any other health problems exsist.  The most common reason for swelling or "enlargement" of the left side of the heart is high blood pressure.  Over time, the constant pumping of the left side of your heart (the left ventricle) against high pressure, could cause the muscle to thicken (this wouldn't really be "swelling" so much as "thickening").  Sometimes people don't know thay have high blood pressure, so it goes uncontrolled over a  long period of time.

Folks at age 44 don't normally check their blood pressure regularly and it isn't uncommon to find high blood pressure in this group.

More information would be helpful.