The human body contains three main coronary arteries that provide oxygen and nutrients to the heart and multiple smaller coronary arteries. The smaller coronary arteries branch off from the main ones.
The heart receives all of its oxygen and nutrients from the three coronary arteries. The left side of the heart receives the oxygen and nutrients from the left coronary artery and the circumflex artery. The left coronary artery comes from the left aortic sinus and the right coronary artery comes from the right aortic sinus. Compared to other arteries in the human body, the coronary arteries are relatively small.