Characteristic pathological finding in carcinoid of heart –
**Core Concept**
The question is testing knowledge of the characteristic pathological findings associated with carcinoid heart disease, a complication of carcinoid tumors that secrete serotonin. Carcinoid heart disease primarily affects the right side of the heart, leading to fibrosis and valve damage.
**Why the Correct Answer is Right**
Carcinoid heart disease is characterized by fibrosis of the endocardium, particularly on the right side of the heart. This fibrosis results from the deposition of collagen and other connective tissue proteins in response to chronic exposure to serotonin (5-HT) and other vasoactive substances secreted by the carcinoid tumor. The fibrosis can lead to valve damage, particularly of the tricuspid and pulmonary valves. The characteristic pathological finding is the presence of "carcinoid plaques" or "carcinoid heart disease plaques" on the endocardial surface of the affected valves.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not specify a characteristic pathological finding associated with carcinoid heart disease.
**Option B:** This option is incorrect because it is too vague and does not accurately describe the specific pathological changes seen in carcinoid heart disease.
**Option C:** This option is incorrect because it is not a recognized pathological finding associated with carcinoid heart disease.
**Clinical Pearl / High-Yield Fact**
It is essential to remember that carcinoid heart disease is a complication of carcinoid tumors, particularly those that secrete serotonin. The presence of carcinoid plaques on the endocardial surface of the right heart valves is a key diagnostic feature of this condition.
**Correct Answer:** D.