Coronary blood flow (Right ventricle), true is:
**Core Concept**
Coronary blood flow regulation is crucial for maintaining cardiac function, particularly in the right ventricle, which has a higher oxygen demand due to its thick walls and high-pressure output. The regulation of coronary blood flow is primarily governed by the autoregulatory response to changes in myocardial oxygen demand.
**Why the Correct Answer is Right**
In the right ventricle, coronary blood flow is predominantly supplied by the right coronary artery (RCA), which is responsible for perfusing the right ventricular free wall. The RCA branches into smaller vessels, including the posterior descending artery (PDA), which supplies the posterior aspect of the right ventricle. The autoregulatory response to increased oxygen demand is mediated by the release of vasodilatory substances, such as adenosine and nitric oxide, which cause blood vessels to dilate and increase blood flow to the right ventricle. This ensures that the right ventricle receives adequate oxygenation to maintain its high-energy demands.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not specify the primary artery responsible for perfusing the right ventricle.
**Option B:** This option is incorrect because it mentions the left coronary artery, which primarily supplies the left ventricle.
**Option C:** This option is incorrect because it mentions the left anterior descending artery (LAD), which is a branch of the left coronary artery and primarily supplies the anterior wall of the left ventricle.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the right coronary artery is the primary supplier of blood to the right ventricle, and its compromise can lead to right ventricular ischemia and dysfunction.
**Correct Answer: C. Left anterior descending artery (LAD) primarily supplies the anterior wall of the left ventricle.**