How did heart come to refer to the shape?

The History of the Heart Shape

The origin of the heart shape ideograph as a symbol of love

Heart symbol - Wikipedia

How the Heart Shape Got Its Name and Why it Looks Nothing Like the Human Heart

Million Hearts has leaf that look like heart shape mean give million hearts to be loved Stock Photo - Alamy

Referred pain - Wikipedia

doodle heart shape - Clip Art Library

Heart Hollow Unfinished Wood Shape Piece Cutout for DIY Craft Projects

Origins of the Love Heart Symbol

Enlarged Heart (Cardiomegaly): Causes, Treatment, and More

Basic Heart Shape - ClipArt Best