Block 3 - ACS Flashcards
What is CAD?
Reduced oxygen and nutrients supplied to myocardium as a result of reduced blood flow
What is CHD?
Buildup of plaque in coronary arteries
What is coronary circulation?
Blood flow to and from myocardium through coronary arteries and cardiac veins
What is angina pectoris?
Chest pain and discomfort due to heart not being able to receive enough perfusion of blood
What is myocardial ischemia?
Restriction of blood supply to heart muscle tissues, causing a shortage of oxygen and nutrients
What is MI?
an area of tissue death, or necrosis, related to obstructed blood flow to the myocardium
What causes MI?
atherosclerosis leading to a thromboembolism
What is auto regulation?
The brain maintains constant blood flow despite changes in perfusion pressure
What does the process of oxygenation consist of?
Ventilation, diffusion, and perfusion are essential for gas exchange to occur
Who are more at risk of CHD deaths?
Women, AA
What are Life’s simple 7 points?
- BP
- Physical activity
- Cholesterol
- Diet
- Weight
- Smoking status
- Blood glucose level
What are the medications used of CAD?
- AntiHTN
- Statins
- Insulin
Lifestyle modifications ____ risk factors for CAD
Lower
What is the function of coronary arteries?
Blood vessels that deliver necessary supplies of oxygen and nutrients required by myocardial cells to function and survive
Most blood flow to the myocardium is delivered during _____
Ventricular diastole
What does the left coronary artery supply blood to?
- Left atrium
- Left ventricle
- intervetricular septum
- AV bundles
What does the right coronary artery supply blood to? Why is it important?
- Right atrium
- Right ventricle
- interventriculat septum
- SA and AV nodes
Helps with cardiac conduction
What is the purpose of coronary collateral circulation?
Preserves function by enabling an alternative route for delivery of blood to the myocardium
When O2 exchange is insufficient, coronary arteries ___ to ___ blood flow
Dilate; increase
What can lead to narrowing of coronary arteries?
Atherosclerotic plaque → decrease BF → asymptomatic until blood is obstructed
Why is O2 balance important in cardiac tissue?
- Key to the production of sufficient arterial pressure to perfuse systemic and coronary circulation
- Coronary artery flow is reduced during systole
- Blood is delivered through the coronary arteries during diastole
What is coronary perfusion pressure?
The pressure of blood through coronary circulation from a pressure gradient between aortic and right atrial pressure
What factors are determined by MC O2 demand and consumption?
- HR
- Systolic pressure
- Left ventricular contractility
Injury of heart muscle can decrease blood flow leading to _____
hypoxia of myocardial cells
What happens to the heart if the blood supply is compromised for 10-15 minutes?
Myocardial cell injury is reversible and can recover to normal function
What happens to the heart if the blood supply is compromised for over 20 minutes?
- Death of myocardial fibers
- Irreversible injury is dependent of coronary collateral circulation
What factors accelerate myocardial injury?
- Increased MC O2 requirement (hypotension, vasospasm, tachycardia)
- Low O2 delivery (Hypotension, anemia)
Describe irreversible injury progression?
Subendocardium (inner) → subepicardium (outer)
A person may experience brief periods of ___ QD w/o ____
Ischemia; myocardial necrosis
What is stroke volume?
Amount of blood pumped from the ventricle during one contraction
What is preload?
Amount of volume in the right or left ventricle at the end of diastole
What is after load?
Pressure that the heart has to contract against to eject blood from the ventricle during systole