The original meaning of the heart is that of two phi based shells united to form a heart. See image below. So it is a metaphor of the unity achieved after conflict. Five, an odd number, plus 5, equals 10 an even number. The riddle of numerology is as such: 5 or phives next phase is 6 or six which is another code for sex or the unity of material forms. In many images, Venus is seen emerging from the shell.
The heart as an occult image makes up a group of symbols know as Veve's. These symbols are Venusian and often used in Yoruban ritualistic practices. The heart symbol acts as a beacon, as all symbols do, to attract specific spirits in the genus of the Lao. In this case a type of spirit who is generally related to carnal pleasures, luxury, beauty and so forth (Erzulie). Such symbols are used to draw these forces down to Earth especially during the new Moon. Sacrifices and offerings are generally placed on top of them, in the instance of clothes the offering is generally wearing them.