Cardiac Markers Overview

Study Notes

Creatine Kinase (CK)

Normal range for males: 55–170 units/L
Normal range for females: 30–135 units/L
CK is found in cardiac muscle, skeletal muscle, and brain
Elevated CK levels indicate injury to muscle cells
CK levels peak 4–6 hours after muscle injury, remain elevated for 12–24 hours, and return to normal within 3–4 days

Creatine Kinase-MB (CK-MB)

CK-MB is a specific type of CK found primarily in cardiac muscle
CK-MB levels are usually less than 6% of total CK levels
Elevated CK-MB levels indicate cardiac injury, such as acute myocardial infarction (AMI), cardiac ischemia, myocarditis, cardiac contusion, and/or defibrillation
CK-MB levels peak 4–6 hours after cardiac injury, remain elevated for 18–24 hours, and return to normal within 3–4 days

Cardiac Troponin T

Cardiac troponin T is a protein found specifically in cardiac muscle
Elevated cardiac troponin T levels indicate AMI and/or unstable angina
Levels rise 1–3 hours after cardiac injury, remain elevated for 12–16 hours, and return to normal within 10–14 days

Cardiac Troponin I

Cardiac troponin I is a protein found exclusively in cardiac muscle
Normal range: 0.1–0.5 ng/mL
Elevated cardiac troponin I levels also indicate AMI and/or unstable angina
Levels rise 1–3 hours after cardiac injury, remain elevated for 12–16 hours, and return to normal within 5–9 days

Creatine Kinase

Creatine Kinase (CK) is an enzyme found in cardiac muscle, skeletal muscle, and the brain
Elevated levels indicate muscle cell injury
Normal ranges for males: 55–170 units/L
Normal ranges for females: 30–135 units/L

Creatine Kinase-MB (CK-MB)

CK-MB is a specific subtype of CK found primarily in cardiac muscle
Elevated levels indicate cardiac injury, such as acute myocardial infarction (AMI), cardiac ischemia, myocarditis, cardiac contusion, and/or defibrillation
Normal range: 0–6% of total CK

Cardiac Troponin T

Cardiac Troponin T is a protein found in cardiac muscle
Elevated levels indicate AMI and/or unstable angina
Normal range: <0.1 ng/mL

Cardiac Troponin I

Cardiac Troponin I is a protein found in cardiac muscle
Elevated levels indicate AMI and/or unstable angina
Normal range: 0.1–0.5 ng/mL

Time Course of Elevations

CK and CK-MB:
- Peak levels: 4-6 hours after injury
- Return to normal levels: 12-24 hours after injury
- May remain elevated for 3-4 days
Cardiac Troponin T:
- Peak levels: 1-3 hours after injury
- Return to normal levels: 12-16 hours after injury
- May remain elevated up to 10-14 days
Cardiac Troponin I:
- Peak levels: 1-3 hours after injury
- Return to normal levels: 12-16 hours after injury
- May remain elevated up to 5-9 days

Description

This quiz covers key information about cardiac markers such as Creatine Kinase (CK), Creatine Kinase-MB (CK-MB), and Cardiac Troponin T. You will learn about normal ranges, significance of elevated levels, and the timing of peaks after muscle and cardiac injuries. Test your understanding of these important biomarkers in cardiac health.