Myocardium rhymes with:
chriptosporidium, compendium, cryptosporidium, idiom, indium, iridium, medium, nephridium, odiaum, palladium, plasmodium, podium, presidium, radium, rhodium, sodium, stadium, tedium, vanadium
Myocardium sounds like:
macartney, majordomo, mccartan, mccarten, mccartin, mccartney, mccrudden, microdyne, migration, miscreation, miseration, mozartean