It's the coronary blood supply.
the veins supply the heart and the heart pumps the blood around the body
If the blood supply to the heart muscles is blocked, a heart attack is likely.
The coronary blood supply is the arteries which supply the heart itself; in order for the heart to function it needs a good supply of oxygen just the same as any other organ/muscle. Without the coronary blood supply the heart would not be able to pump blood around the body, a disruption in this blood supply would cause a heart attack.
To provide the heart with a blood supply.
When blood supply to the heart is blocked what happens is a myocardial infarction which can result in death.
Blood
The heart purifies the impure blood and supply the pure blood to all the organs of the body
Veins. Veins carry unoxygenated blood towards the heart.
The heart muscle that has its own supply of blood from vessels is called the myocardium. It receives its blood supply primarily through the coronary arteries, which branch off from the aorta. This blood supply is crucial for delivering oxygen and nutrients to the heart muscle, enabling it to function effectively.
Oxygen to the heart.
When blood supply to the heart is blocked what happens is a myocardial infarction which can result in death.
The heart is made up of an intricate web of blood vessels (coronary arteries) that ensure an adequate supply of blood rich in oxygen and nutrients.