NURS 215 FINAL: heart, conduction, and circulation

what are the two circuits of the heart?

pulmonary and systemic

what is the pulmonary circuit?

low pressure system, rv to la. picks up oxygen at lungs

what is the systemic circuit?

high pressure system, lv to ra. delivers oxygen to body tissues

what is the SA node?

heart's natural pacemaker. initates electrical impulse

what is the AV node?

gatekeeper and briefly delays signal

what are the purkinje fibers?

they distribute impulse throughout ventricles

what is angina pectoris?

chest pain due to myocardial infarction. two types are unstable and chronic stable

what is unstable angina?

new episode or increased severity. cardiac tissue oxygen demands exceeds delivery. not relieved with rest. medical emergency. caused by myocardial ischemia

what is the pathophysiology of chronic stable angina?

consistent, chronic pain. caused by narrowing coronary arteries from atherosclerosis. chest pain occurs when exertion or stress, when the heart needs more oxygen. self medication with nitroglycerin.

what is myocardial ischemia?

blood clot, atherosclerotic plaque, coronary artery vasospasm, microvascular obstruction

what is prinzmetal's angina?

variant or vasoplastic angina. angina while at rest. unclear etiology

what is a acute myocardial infarction?

prolonged cardiac tissue ischemia due to atherosclerotic plaque, thrombus, or increased myocardial demand

what is a type 1 MI?

spontaneous due to plaque or thrombus

what is a type 2 MI?

lack of oxygen to meet demands

what is a type 3 MI?

mi death before cTn measurement

what is a type 4 MI?

mi due to stent insertion

what is a type 5 MI?

mi due to cabg

what are the complications of a MI?

dysrhythmias, papillary muscle rupture, and thromboembolism, ventricular aneurysm and rupture, pericarditis, heart failure

what is the pathophysiology of a dysrhythmia?

ischemic areas do not conduct impulses as expected. excitable activation occurs, disrupting normal rhythm