This is a pattern for a more-or-less anatomically correct human heart. It is made by crocheting the ventricles and right and left atria as separate pieces which are then stitched together.

It includes instructions for the major blood vessels (pulmonary veins and arteries, vena cava and aorta) as well as coronary blood vessels.

You can use any DK yarn, and you’ll need some toy stuffing too.

The gauge isn’t important!