There are 3 main heart arteries: Left Anterior Descending (LAD), Circumflex (Circ) and Right Coronary Artery (RCA)) and their respective branches each supply a designated portion of the heart. The Left Anterior Descending (LAD) supplies blood to the front (anterior) portion of the heart and the septum. The Circ supplies the back (posterior) portion of the left ventricle. The RCA supplies the bottom (inferior) portion of the ventricle and also the right ventricle in 90% of cases. In the other 10%, the Circ sends a branch to the inferior wall of the LV.
Here are a couple articles you may want to review:
Angioplasty and Stents
Anterior Heart Arteries