NUR 339 Exam 5 - Answer impaired coronary blood flow 2. other na...

NUR 339 Exam 5

• What is coronary heart disease caused by?

Answer impaired coronary blood flow

• other names for coronary heart disease

Answer ischemic heart disease or coronary artery disease

• main cause of coronary heart disease

Answer atherosclerosis

• What dose coronary heart disease include?

Answer angina myocardial infarction

cardiac dysrhythmias and conduction defects heart failure sudden death

• What structure do the left and right coronary arteries arise from?

Answer aortic arch just past aortic valve

• What does the left coronary artery split into?

Answer left anterior descending artery circumflex

• What does the left anterior descending artery supply?

Answer the LV, ant. portion of septum, and the papillary muscle 1 / 3

• what does the circumflex supply?

Answer left lateral wall of LV

• What does the right coronary artery supply?

Answer the SA node and RV

• What is the SA nodes job?

Answer pacemaker of the heart starts the impulse

• what does the posterior descending artery supply?

Answer the posterior septum, ventricle, and posterior papillary muscle

• Where do the coronary arteries lie?

Answer on the outside of heart with smaller branches moving thru to supply circulation to subendocardium (inner layer of the heart)

• When are the coronary arteries mostly perfused?

Answer diastole

• What are the coronary arteries affected by?

Answer HR

Aortic pressure - autoregulation allows constant blood flow to coronary arteries at mean arterial pressure of 60-180

• What is the effect of tachycardia on coronary artery perfusion?

Answer 2 / 3

shortens the diastolic time when it gets fast

not enough diastolic time = not enough time for heart to be perfused (ischemic)

• What is the effect of severe hypotension on coronary artery perfusion?

Answer -

decreased coronary artery perfusion

• metabolic control of coronary circulation

Answer heart muscle needs fatty acids & aerobic metabolism to meet energy needs blood flow regulated by O2 needs of myocardium

• how do periods of strenuous exercise affect the blood flow thru the coro- nary arteries?

Answer coronary arteries can increase blood flow 4-5 x to meet demands needed

• What is released from the myocardial cells in response to decrease O2 supply r/t demand?

Answer metabolic mediators (K, lactic acid, CO2, & adenosine) cause vasodilation

• What factors are secreted by endothelial cells lining the coronary arteries that affect blood

flow?

Answer vasodilating factors

vasoconstricting factors anti-thrombogenic factors

• When is nitric oxide released (vasodilating factors)?

Answer when the endothelium comes in contact with aggregating platelets, thrombin, products of mast

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