Troponin-T is a marker of-
**Core Concept**
Troponin-T is a protein found in cardiac muscle cells, and its elevation in the blood is a sensitive indicator of cardiac damage. It is part of the troponin complex, which plays a crucial role in muscle contraction. The troponin complex includes **troponin C**, **troponin I**, and **troponin T**, each with distinct functions.
**Why the Correct Answer is Right**
Troponin-T is specifically associated with cardiac muscle and is released into the bloodstream when cardiac cells are damaged, as in **myocardial infarction**. This makes it a highly specific marker for cardiac injury. The sensitivity and specificity of troponin-T for detecting myocardial damage are high, making it a preferred diagnostic tool in clinical settings.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because while troponin-T is a marker of cardiac damage, the options are not provided to assess this statement directly.
**Option B:** Similarly, without the specific options, we cannot directly address why each might be incorrect, but generally, troponin-T's specificity to cardiac muscle damage makes other options less relevant.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that troponin levels can remain elevated for several days after a cardiac event, making them useful for diagnosing **myocardial infarction** even if the patient presents late.
**Correct Answer:** D. Myocardial infarction