Cardiac biomarkers are substances released into the bloodstream when the heart is damaged or stressed. Measurements of these biomarkers are used to help diagnose acute coronary syndrome (ACS) and cardiac ischemia, conditions associated with insufficient blood flow to the heart. Tests for cardiac biomarkers can also be used to help determine a person’s risk of having these conditions or to help monitor and manage someone with suspected ACS and cardiac ischemia.
The main causes of ACS and cardiac ischemia are usually plaque build up in the walls of the arteries and hardening of the arteries (atherosclerosis). This can result in severe narrowing of the arteries leading to the heart or sudden blockage of blood flow through these coronary arteries.
Cardiac ischemia is caused when the blood supply to the heart tissue is not enough to meet the needs of the heart. When there is not enough blood in the heart, it can cause chest pain (angina), shortness of breath, sweating, and other symptoms. Typical angina pectoris occurs when the coronary arteries are gradually narrowed over time. The pain starts when a person is active, making the heart work harder, and is quickly relieved by rest or by medications that increase blood flow to the heart, such as nitroglycerin.
ACS is caused by the rupture of a plaque coming from atherosclerosis. Fracture of the plaque causes the formation of blood clots (thrombi) in the coronary arteries, which results in a sudden drop in the amount of blood and oxygen that reaches the heart. A sudden drop in the heart’s blood supply can cause prolonged chest pain called unstable angina, which often occurs at rest or is not relieved by rest or nitroglycerin.
When blood flow to the heart is blocked or significantly reduced over a longer period of time (usually more than 30-60 minutes), it can cause the heart cells to die and is called an acute myocardial infarction (AMI or attack in the heart). This leads to the death of the affected part of the heart muscle with permanent damage and heart pain and can sometimes cause sudden death-causing irregular heart contractions (arrhythmia). Unstable angina and AMI are collectively called acute coronary syndrome as both are due to a very sharp drop in blood flow to the heart.
It is important to distinguish heart attacks from angina, heart failure, or other conditions that may have similar signs and symptoms because treatments and monitoring requirements are different. Cardiac biomarker tests have been ordered to help detect the presence of ACS and cardiac ischemia and assess their severity. Increases in one or more indicators of cardiac biocardia in the blood can identify persons with ACS or cardiac ischemia, allowing rapid and accurate diagnosis and appropriate treatment of their condition.
For ACS, prompt medical intervention is essential to prevent death and minimize heart damage and future complications. Finally, multiple cardiac biomarker tests are performed over several hours to ensure that an increase in blood level is not missed and to assess the severity of a heart attack.
- Troponin-I quantum
- hsCRP quantum
- CK-MB quantum.