Heart: Electrical Conduction & Blood Flow Flashcards
Electrical Conduction:
- Sinoatrial (SA) node
pacemaker
the upper chambers of the heart begins to squeeze and generates impulses
Electrical Conduction:
- Atrioventricular (AV) node
electricity travels slower in the AV node and the slowing effect gives the ventricles enough time to expand and fill up with blood
the impulses pause at the AV node
Electrical Conduction:
- Bundle of His
extends outward from the AV node and travels down the center of the heart
because it conducts electricity faster than surrounding tissue, it functions much like a lightning rod, directing the electrical cascade further into the heart
Electrical Conduction:
- Bundle Branches
bundle of his splits into two branches
the branches carry the electrical cascade to the outer areas of the heart, especially the ventricles
Electrical Conduction:
- Purkinje Fibers
electricity travels down and then spreads out at the bottom of the heart
electricity then travels upward and along the outer areas of the heart
(heart pumps blood upward and out of the heart)
disrupts flow of oxygenated blood to tissues
S/S:
pallor
pain
weak or absent pulse
poor capillary refill
cool skin
tissue dysfunction
Peripheral Arterial Abnormalities
disrupts blood return to the heart
S/S:
edema
brown skin discoloration
tissue dysfunction (stasis ulcers)
Peripheral Venous Abnormalities
blood flow in the heart
superior/inferior vena cava
right atrium
tricuspid valve
right ventricle
pulmonary valve
pulmonary artery
(lungs - deoxygenated blood to become oxygenated)
pulmonary vein
left atrium
mitral valve
left ventricle
aortic valve
aorta
(systemic - spread oxygenated blood to the body)
Tough, fibrous, double-walled sac that surrounds and protects heart
Pericardium
Muscular wall of heart
It does the pumping
Myocardium
Thin layer of endothelial tissue that lines inner surface of heart chambers and valves
Endocardium
