Serum enzyme used for MI –
**Question:** Serum enzyme used for MI -
A. Creatine Phosphokinase (CPK)
B. Alkaline Phosphatase
C. Aspartate Aminotransferase (AST)
D. Alanine Aminotransferase (ALT)
**Core Concept:**
Cardiovascular diseases, particularly myocardial infarction (MI), involve damage to the myocardium, leading to an increase in serum enzymes due to the leakage from the damaged cells. Cardiac-specific enzymes are more reliable for diagnosing MI compared to general enzymes like alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase, which are commonly found in various tissues and organs.
**Why the Correct Answer is Right:**
Creatine Phosphokinase (CPK) is a group of enzymes found in various tissues, including heart, brain, and skeletal muscles. In MI, CPK levels rise due to myocardial damage, making it a useful biomarker for diagnosing and monitoring the disease.
**Why Each Wrong Option is Incorrect:**
1. Alkaline Phosphatase (B) is primarily found in the liver and bile ducts and is not specific to the heart. Elevated alkaline phosphatase levels are often seen in liver diseases, biliary disorders, and some malignancies.
2. Aspartate Aminotransferase (C) is involved in amino acid transport and is primarily found in the liver and skeletal muscles. AST elevation is commonly seen in liver diseases, viral hepatitis, and myocardial infarction.
3. Alanine Aminotransferase (D) is involved in amino acid transport and is primarily found in the liver, pancreas, and skeletal muscles. ALT elevation is commonly seen in liver diseases, alcoholic hepatitis, and myocardial infarction.
**Clinical Pearl:**
Diagnosis and monitoring of myocardial infarction frequently involve utilizing cardiac-specific enzymes like creatine phosphokinase, troponins, and myoglobin. While these enzymes are more specific to the heart, their levels can be influenced by various factors. A comprehensive interpretation of these markers, along with clinical, electrocardiographic, and echocardiographic findings, helps in making a definite diagnosis of myocardial infarction.