Cardiovascular Flashcards
Blood flow is controlled related to the ____ needs?
Tissue needs
What creates turbulent blood flow?
Sharp vascular turns, atherosclerotic disease, unhelathy endothelium, narrowing (CAD), valvular disease
Blood flow equation?
Q = ^P/R Q = flow, ^P = pressure gradient, R = resistance
Flow and pressure gradient have a ____ relationship?
Symbiotic relationship - increase or decrease together
Flow and resistance have a ____ relationship?
Inverse. An increase in one causes a decrease in the other
An increase in viscosity cause a ____ in flow
Decrease. Increase in viscosity causes an increase in resistance
Increasing diameter of vessels causes an _____ in flow?
increase
What is capacitance?
Quantity of blood to store. Distensibility X volume
S/s of arterial disease?
Decreased pulse, cool lower extremities. Pain with walking. Pallor or Rubor. Hairless. Arterial or ischemic ulcers.
S/s of venous disease?
Edematous lower extremities. Dark pigmentation all the way around the leg. Painless venous ulcers. Can progress to lymph disease.
What is the function of the hydrostatic pressure in fluid shifts?
Hydrostatic pressure = BP. Pushes fluid out of the vascular space into the interstitial space.
What is the function of the plasma protein osmotic pressure?
Also known as oncotic pressure. Plasma proteins (albumin) pulls fluids back into the vascular space.
What is lab value to measure osmotic pressure?
Sodium.
What is lymph made of?
Interstitial fluid. Salts, fats, glucose, water, WBCs.
Short term control of blood flow is regulated by…
increased metabolism rate or decreased oxygen availability
What are the local vasodilators?
Adenosine, lactate, CO2, histamine, ADP, hydrogen
What is autoregulation?
The ability of each tissue to adjust its vascular resistance to maintain normal blood flow
What does shear stress cause?
Uses more oxygen, metabolic rate
Cardiac output is what?
The sum of all local tissue flows
Arterial pressure regulation is independent of?
Local blood flow control and cardiac output control
What factor plays the greatest role in determining blood flow?
Diameter of the vessel!
LaPlace’s Law:
Wall tension increases as radius increases = wall thickness decreases
Long term regulation of blood flow occurs by…
Increase in size and number of vessels (angiogenesis)
Angiogenesis is stimulated by
oxygen!
What are the humoral vasodilators?
Bradykinin, serotonin, nitric oxide, histamine, prostaglandins
Sympathetic controls…
Circulation
Parasympathetic controls…
Heart function!
Equation for arterial pressure is
cardiac output x total peripheral resistance
Alpha 1 stimulates….
Vasoconstriction
Alpha 2 stimulates…
Vasodilation
Beta 1 stimulates…
+ Inotropy, chronotrophy, dromotrophy (speed of AV node conduction), secretes renin
Beta 2 stimulates…
Bronchodilator, smooth muscle relaxation, decrease in GI motility
What are chemoreceptors stimulated by?
Decrease in 02, increase in CO2, increase in H+
What does aldosterone stimulate?
Na and water retention = increase in volume = increase in BP
Normal BP parameters?
< 120/<80
Stage 1 HTN parameters?
140-159 / 90-99
Stage 2 HTN parameters?
> 160/ > 100
What are the two types of renal artery stenosis?
Fibromuscular dysplasia (females) & atherosclerosis (men)
S/s of pheochromocytoma?
Intermittent HTN, palpitations, sweating, anxiety (s/t secretion of catecholamines)
Lab values found in hyperaldosteronism?
High sodium, low potassium w/ HTN.
List the functions of nitric oxide…
Vasodilation (direct and indirect), anti-thrombotic, Anti-inflammatory, Anti-proliferative (prevents hyperplasia)
List the risk factors for atherosclerosis
Age (men > 45, women > 55). DM, HTN, HLD, Smoking, Genetics
What does LDL cholesterol do?
Transports cholesterol from the liver, deposits it into the cells. “Bad”
What does HDL cholesterol do?
Transports cholesterol from the arteries back the liver “Good”.
What do triglycerides do?
Transports lipids to be stored as adipose tissue.
What do statins inhibit?
HMG CoA Reductase - a step in the process of cholesterol metabolism
The process of atherosclerotic plaque development
Monocyte -> intimal layer -> macrophage -> ingests lipids -> becomes foam cell -> inflammation, growth
What is chronic stable angina?
Atherosclerotic lesions have narrowed lumen. Increased 02 demand (exercise) causes reversible ischemia.
What happens in ACS?
Rupture of unstable plaque causes platelet aggregation, clotting, blockage.
What happens during formation of an aneurysm?
Chronic inflammation, hypertension, shear forces cause weakening and remodeling. Plaque formation further erodes vessel wall.
What is a type A dissection?
Involves the ascending aorta.
What are the three things needed for reentry dysrhythmia?
Dual pathway, retrograde conduction, and a block
What are acyanotic defects?
Left to right shunt
Examples of acyanotic defects?
PDA, ASD, VSD
What are cyanotic defects?
Right to left shunt
Examples of cyanotic defects?
Tet of fellot, tricuspid atresia
