CARDIO EXAM

Question 1

different qualities of the vessels

Answer 1

-veins- carry most blood volume, low pressure, high capacitance
-arteries- highest velocity, diameter
-capillaries- highest area, decreased flow

Question 2

blood pressure

Answer 2

-pulsates due to diastole and systole up until arterioles
-arterioles unaffected by contraction pressure changes
-drop in pressure at arterioles
-MAP- average pressure in complete cardiac cycle
-pressure decreases as you move through the system due to energy loss to overcoming frictional resistances

Question 3

sympathetic affect on cardiovascular

Answer 3

-alpha 1 adrenergic- vasoconstriction including skeletal
-beta 2 adrenergic- vasodilation in skeletal muscle
-beta 1- increase HR, increase contractility, increase velocity conductance (increase rate of phase 4 depolarization in SA)

Question 4

selective perfusion

Answer 4

-not all capillaries have blood at all times
-depends on metabolic needs of the tissues
-regulate via constriction and dilation of arterioles

Question 5

factors affecting blood flow

Answer 5

-1. pressure difference in vessel (driving force)- high difference, high flow
-2. resistance- high resistance, low flow
-3. area of the vessel (large vessels have low area and small have high) -> increased area has low flow

Question 6

factors affecting resistance

Answer 6

-1. viscosity- high viscosity, high resistance
-2. length of vessel- increased length, high resistance
-3. diameter- small diameter, high resistance
-poiseuille equation

Question 7

TPR

Answer 7

-sequential/series flow- flow is equal at all levels BUT pressure decreases as it flows through (greatest drop at arterioles)
-parallel blood flow- no pressure loss in major arteries BUT flow through each organ is fraction of total blood flow
-in parallel blood flow the total peripheral resistance is < any individual resistance

Question 8

anemia

Answer 8

-low viscosity -> low resistance -> high flow
-higher turbulence bc low viscosity
-high OC

Question 9

thrombi

Answer 9

-increase velocity AT THE SITE of the thrombi -> increase turbulence

Question 10

shear

Answer 10

-shear is highest at wall (large difference in flow)
-no sheer in middle -> all at same speed
-shear breaks up clusters of RBCs -> decrease viscosity
-RBC clumps and viscosity is lowest at walls bc the high sheer

Question 11

diastole

Answer 11

-we are in diastole more than we are in systole

Question 12

sympathetic and parasympathetic innervation

Answer 12

-beta 1- HR, contractility, conduction, venoconstriction
-beta 2- vasodilation, bronchodilation
-alpha 1- vasoconstriction (peripheral)
-increased parasympathetic- decreases Ca, decrease HR

Question 13

refractory period

Answer 13

-absolute- no stimulus can generate
-effective- not enough inward current to conduct to next site
-relative- large stimulus required
-supranormal period- less current required

Question 14

aortic stenosis

Answer 14

-decrease SV
-decrease systolic, pulse, and mean arterial pressure
-increase afterload

Question 15

arteriosclerosis

Answer 15

-decrease diameter, increase resistance
-increase systolic, pulse, and mean arterial pressure
-increase afterload

Question 16

ventricle/atria depolarization

Answer 16

-Na inward

Question 17

SA node depolarization

Answer 17

-inward Ca
-no sustained plateau

Question 18

phases of cardiac cycle

Answer 18

-atrial systole- ventricular filling - P WAVE, PR
-isovolumetric ventricular contraction- ventricles contract, ventricular pressure increase, volume is constant, all vales close -> QRS + S1
-rapid ventricular ejection- ventricles contract, decrease volume, aortic pressure increase -> ST segment
-reduced ventricular ejection- ventricular volume at lowest, aortic pressure drops -> T WAVE
-isovolumetric ventricular ejection- ventricles relaxed all valves close -> S2
-rapid ventricular filling- ventricles are relaxed and fill passively -> S3
-reduced ventricular filling (diastasis)- ventricles relaxed

Question 19

venoconstriction

Answer 19

-decrease compliance
-decrease unstressed volume
-increased stressed volume
-increase MAP
-(arteriole constriction decreases CO)

Question 20

positive staircase

Answer 20

-each beat increases Ca which increase tension which increases contractility

Question 21

postextrasystole potentiation

Answer 21

-extrasystole (early) is not forceful bc Ca is lacking
-postextrasystole has increased force due to extra build up of Ca from extrasystole (pts feel this beat)

Question 22

positive ionotropic drugs

Answer 22

-digoxin
-cardiac glycosides
-class work

Question 23

preload

Answer 23

-volume in ventricle before contraction
-increase preload increase CO

Question 24

WNL

Question 25

things that affect blood pressure

Answer 25

-blood volume
-stressed and unstressed volume
-<4 L of blood -> MAP=0

Question 26

hydrostatic pressure

Answer 26

-arteriolar dilation
-venous constriction
-increase venous pressure
-heart failure
-ECF volume expansion