Question

Which of the following statements are TRUE regarding the coronary circulation?

A) The RCA, the LAD coronary artery, and the LCX are the major "trunk" arteries that supply large areas of the heart.
B) The right and left coronary arteries originate from the aorta.
C) The heart protects itself with cross-connections between arteries (collateral circulation).
D) The majority of myocardial blood flow occurs during diastole.
E) All of the above are true.

Answer 1

All of the statements (A to D) about the coronary circulation are true, indicating that the major trunk arteries supply large areas of the heart, originate from the aorta, have collateral connections, and that myocardial blood flow primarily occurs during diastole.

Step-by-step explanation:

Each of the statements provided regarding the coronary circulation is TRUE:

• (A) The right coronary artery (RCA), the left anterior descending (LAD) coronary artery, and the left circumflex artery (LCX) are indeed the primary "trunk" arteries that supply large areas of the heart with blood.
• (B) Both the right and left coronary arteries originate from the aorta, specifically from two of the three sinuses located just superior to the aortic semilunar valve.
• (C) The heart does protect itself through collateral circulation, where arteries form anastomoses to create interconnections that can provide blood flow to regions of the heart even if another branch is partially blocked.
• (D) The majority of myocardial blood flow indeed occurs during diastole, when the heart muscle is relaxed, allowing the coronary vessels to fill with blood.

E) All of the above are true.