Cardiac Enzyme Markers Flashcards
(18 cards)
What biomarker is the first to rise after myocardial injury?
myoglobin
Myoglobin is an early marker for myocardial infarction, indicating muscle injury.
What is the significance of CK-MB in myocardial infarction?
Useful to look for reinfarction as it returns to normal after 2-3 days
CK-MB is a specific enzyme that helps in assessing new infarctions due to its rapid normalization.
How long does it take for LDH to begin to rise after myocardial injury?
24-48 hours
LDH is less specific and takes longer to return to normal than other markers.
When does AST begin to rise after myocardial injury?
12-24 hours
AST can also rise in other conditions, making it a less specific marker.
What is the time frame for troponin T to rise after myocardial injury?
4-6 hours
Troponin T is a highly sensitive and specific marker for myocardial damage.
How soon does CK rise after myocardial injury?
4-8 hours
CK is another enzyme that indicates muscle injury but is less specific than troponins.
What is the normal oxygen saturation in the Right side of the heart?
70%
This represents the oxygenation level of deoxygenated blood returning to the heart.
What is the normal oxygen saturation in the Left side of the heart?
100%
This indicates fully oxygenated blood that is pumped to the systemic circulation.
What does Eisenmenger’s syndrome describe?
Reversal of a left-to-right shunt in a congenital heart defect due to pulmonary hypertension
This condition occurs when increased pressure in the pulmonary circulation leads to right-to-left shunting.
What congenital heart defects are associated with Eisenmenger’s syndrome?
- Ventricular septal defect
- Atrial septal defect
- Patent ductus arteriosus
These defects can lead to increased blood flow to the lungs and eventual pulmonary hypertension.
What are some features of Eisenmenger’s syndrome?
- Original murmur may disappear
- Cyanosis
- Clubbing
- Right ventricular failure
- Haemoptysis, embolism
These features arise from chronic hypoxia and heart failure due to increased pulmonary pressure.
What is the management required for Eisenmenger’s syndrome?
Heart-lung transplantation
This is often the only definitive treatment for severe cases.
What effect does an atrial septal defect have on the oxygen saturation of the Right side of the heart?
Causes a rise in oxygen saturation
This occurs due to left-to-right shunting of oxygenated blood from the left atrium.
What effect does a ventricular septal defect have on the oxygen saturation in the right ventricle and pulmonary artery?
Causes a rise only in the right ventricle and pulmonary artery
This is due to the shunting of blood from the left ventricle.
What effect does a patent ductus arteriosus have on oxygen saturation?
Causes only a rise in the pulmonary artery
This occurs as blood flows from the aorta to the pulmonary artery.
What effect does a ventricular septal defect have on left ventricular and aorta saturation?
Causes a decrease in left ventricular and aorta saturation
This is due to the mixing of oxygenated and deoxygenated blood.
What happens to aorta oxygen saturation in PDA with Eisenmenger’s syndrome?
Causes a decrease in aorta oxygen saturation
This results from right-to-left shunting due to elevated pulmonary pressures.
What effect does an atrial septal defect have on the oxygen saturation in the left atria, ventricle, and aorta?
Causes a decrease in the oxygen saturation
This is due to the dilution effect of shunted blood.
