Understanding Lab Tests for Heart Attack (Myocardial Infarction)
Written by Private MD Labs Medical Writing Team • Last Updated: September 8, 2025
A heart attack, medically known as myocardial infarction, occurs when blood flow to part of the heart muscle is blocked, causing tissue damage. While heart attacks are primarily diagnosed through clinical symptoms, EKGs, and imaging studies, blood tests play a crucial supporting role in confirming the diagnosis and assessing the extent of heart muscle damage.
Recommended Test
Lactic Acid Dehydrogenase (LD) (LDH)
LDH is an enzyme that becomes significantly elevated in the bloodstream following a heart attack. When heart muscle cells are damaged during a myocardial infarction, they release LDH and other enzymes into the blood. Measuring LDH levels helps assess the extent of heart muscle damage and can aid in confirming the diagnosis, particularly when used alongside other cardiac markers and clinical findings.
2907 reviews
The Role of Blood Tests in Heart Attack Diagnosis
When heart muscle cells are damaged during a heart attack, they release specific enzymes and proteins into the bloodstream. Blood tests can detect these cardiac markers, providing valuable information about the timing, severity, and extent of heart muscle damage. These tests are fundamental for confirming the diagnosis and monitoring recovery.
Understanding Your Results
Elevated LDH levels following suspected heart attack symptoms can indicate heart muscle damage. However, LDH can also be elevated due to other conditions affecting various organs. For this reason, it's typically interpreted alongside other cardiac-specific markers and clinical findings to provide a complete picture of heart health.
Important Considerations
The information here is for educational purposes only and is not a substitute for professional medical advice. Heart attack is a medical emergency requiring immediate attention. Always consult with a healthcare provider for diagnosis and treatment.
