check this out:

http://www.mannosidosis.org/alexarticle3.htm

One of the symptoms associated with this conditions is cardiomegally (swollen heart). Basically your lysomes (organelles in cells that act a bit like the cells stomach) are missing an enzyme required to digest a particular type of sugar. This sugar them builds up in tissues and causes problems.

Generically these conditions are known as "Lysosomal Storage Diseases".
http://www.sas-centre.org/genetic/genpages/lysstodisindex.html

[Edited by Dr_simon on 02-01-2004 at 01:46 PM]