The myocardium receives its blood supply directly from the

The myocardium receives its blood supply directly from the

(a) aorta,

(b) coronary arteries,

(c) coronary sinus,

(d) pulmonary arteries.

The Correct Answer and Explanation is :

The correct answer is (b) coronary arteries.

Explanation:

The myocardium, which is the muscular layer of the heart, receives its blood supply from the coronary arteries. The coronary arteries are responsible for delivering oxygen-rich blood to the heart muscle, ensuring it has the necessary nutrients and oxygen to function effectively.

Here’s how the process works:

• Aorta: The aorta is the large artery that carries oxygenated blood from the left ventricle of the heart to the rest of the body. While the aorta distributes blood throughout the body, it does not supply blood directly to the heart muscle itself.
• Coronary arteries: The heart’s blood supply comes specifically from two main coronary arteries, which branch off from the aorta just above the aortic valve. These arteries are the left coronary artery (LCA) and the right coronary artery (RCA). The left coronary artery further divides into the left anterior descending (LAD) and circumflex arteries, which supply the majority of the left side of the heart, including the left ventricle. The right coronary artery primarily supplies the right side of the heart and parts of the atria.
• Coronary sinus: The coronary sinus is a large vein that collects deoxygenated blood from the heart muscle and drains it into the right atrium of the heart. It is not responsible for delivering oxygenated blood to the myocardium.
• Pulmonary arteries: The pulmonary arteries carry deoxygenated blood from the right ventricle to the lungs for oxygenation. They do not supply blood to the myocardium.

Therefore, the coronary arteries are crucial for providing the oxygenated blood needed by the myocardium to contract and pump blood effectively throughout the body. Any obstruction or blockage in these arteries (such as in coronary artery disease) can impair the heart’s function and lead to serious health issues, including heart attacks.