Apex of the heart

Overview
The apex of the heart is the lowest superficial part of the heart.

It is directed downward, forward, and to the left, and is overlapped by the left lung and pleura.

External anatomy
It lies behind the fifth left intercostal space, 8 to 9 cm. from the mid-sternal line, slightly medial to the midclavicular line.

Alternately, it can be found about 4 cm. below and 2 mm. to the medial side of the left mammary papilla. It's function is to pump blood from the left atruim