The stmemum is anterior (ventral) to the heart. Meaning it is in front of the heart.
The manubrium
The sternum is a bone in the chest (thorax). It is part of the skeletal system.
On an animals body the thorax is located between the head and abdomen. The thorax is a main division of an insects body. In mammals, thorax is formed by the stemum, thoracic vertebra and ribs.