The heart has its own blood vessels, that surround it and carry oxygenated blood to it. These form a mostly closed loop, from the lungs to the heart and back again.
Nice diagram here.
The vessels supplying the heart come straight from the lungs because the heart is arguably the most essential bodily organ.
One aspect of this is that the exact layout of blood vessels to the heart is not consistent from one person to another. Almost everybody has two primary arteries, the "right" and "left" epicardial coronary arteries (bringing oxygen to the right and left sides of the heart, respectively). But beyond this basic structure, coronary arteries can vary a lot from one person to another.
It doesn't matter that the blood vessel layout varies, as long as each heart gets the oxygen it needs. Some hearts truly don't have enough blood supply, requiring surgery and treatment for the individual affected. The much bigger risk to most people as they get older is that the arteries supplying their heart with oxygen will get clogged by fatty deposits -- leading to death of some of the heart muscle tissue, angina or cardiac arrest.
Nice diagram here.
The vessels supplying the heart come straight from the lungs because the heart is arguably the most essential bodily organ.
One aspect of this is that the exact layout of blood vessels to the heart is not consistent from one person to another. Almost everybody has two primary arteries, the "right" and "left" epicardial coronary arteries (bringing oxygen to the right and left sides of the heart, respectively). But beyond this basic structure, coronary arteries can vary a lot from one person to another.
It doesn't matter that the blood vessel layout varies, as long as each heart gets the oxygen it needs. Some hearts truly don't have enough blood supply, requiring surgery and treatment for the individual affected. The much bigger risk to most people as they get older is that the arteries supplying their heart with oxygen will get clogged by fatty deposits -- leading to death of some of the heart muscle tissue, angina or cardiac arrest.