Lecture 17/18 ish

Question 1

what is the mitral valve between

Answer 1

the left atrium and left ventricle (mitral valve = bicuspid)

Question 2

what is the AV valve between

Answer 2

the aorta and left ventricle

Question 3

what happens in mitral valve regurgitation

Answer 3

failure of mitral valve to close properly during systole results in backflow from the left ventricle into the left atria

• systolic murmur
• increased pressure in the LA causes increased pulmonary venous pressure which leads to pulmonary edema

Question 4

what happens during AV valve regurgitation

Answer 4

aortic valve doesn’t close properly during diastole so blood flows back into the left ventricle from the aorta

-diastolic murmur

Question 5

what happens to pulse pressure if there is a decrease in compliance

Answer 5

pulse pressure will increase
decreased compliance = vessels are stiffer

Question 6

what happens to the pulse pressure in a patient with PDA

Answer 6

it would increase b/c there is lower diastolic pressure and higher systolic pressure

Question 7

hormone released when atrial stretch is reduced
- enhances water reabsorption in renal tubules &
- vasoconstricts peripheral resistance vessels

Answer 7

ADH (anti-diuretic hormone)

Question 8

what hormones result in an increased retention of fluids

Answer 8

renin
aldosterone
angiotensin II
ADH

Question 9

what is VSD

Answer 9

ventricular septum defect = hole in interventricular septum

• during systole, blood flows from the left ventricle into the right ventricle
• The right ventricle gets close to the same pressure as LV (since its getting blood from both the right atrium and LV) which elevates pulmonary artery pressure and flow

-RV hypertrophy and mild LV hypertrophy

-systolic murmur

Question 10

explain PDA
what type of murmur
what happens

Answer 10

continuous murmur b/c
- during systole, aortic pressure is much higher than the pressure in the pulmonary artery so blood flows from the aorta to the pulmonary artery (backwards)

-during diastole, the aortic pressure remains higher than the pulmonary artery pressure thus maintaining the murmur

Question 11

what happens to the EDV in VSD

Answer 11

EDV increases b/c there is an increased volume of blood in the ventricles

Question 12

what happens to the ESV in VSD

Answer 12

ESV increases due to the increased volume of blood still remaining in ventricles after systole

Question 13

what happens to SV in VSD

Answer 13

SV decreases as hypertrophy and an increased afterload makes it harder for the ventricles to pump out the blood volume

Question 14

explain the atrial receptor reflex and what happens when it is active vs less active

Answer 14

atrial receptor reflex are stretch receptors in the L&R atria and pulmonary veins that respond to changes in volume

an increased volume in the atria activates the receptors (increases rate of APs)
—> ANP release
—- vasodilates and inhibits renin

a decreased volume in atria would reduce the rate of APs at the receptors
—> ADH release which stimulates renin release
—> increased thirst

Question 15

what things affect TPR

Answer 15

local controls (O2, CO2, pH)
arteriolar radius
blood viscosity
blood vessel length

Question 16

explain what happens during the defense alarm reaction

Answer 16

baroreceptor reflex undergoes a change in setpoint in order to maintain a high BP

increased sympathetic (NE, EPi release)
release of Angiotensin II and ADH
increased BP, SV, HR
vasoconstriction of non-critical organs
vasodilation of coronary vessels and working muscle

Question 17

what is the CV systems response to exercise?

Answer 17

the increased demand for O2 and CO2 removal is met by an increased CO and redirection of blood flow

Question 18

hormone released when plasma osmolarity or blood pressure is low that causes arteriolar vasoconstriction and increases the reabsorption of water in the kidneys

Answer 18

ADH/AVP (vasopressin)

Question 19

what is the effect of epinephrine on B2 adrenergic receptors?

Answer 19

causes the relaxation of smooth muscle at arterioles and skeletal muscle

Question 20

what hormone would be released in a hypovolemic state (fluid loss)

Answer 20

ADH
- increases kidney ability to reabsorb water
- causes vasoconstriction

Question 21

what hormone(s) would be released in a hypervolemic state (excess fluid)

Answer 21

ANP
- targets kidneys to decrease Na+ reabsorption
- promotes vasodilation
- inhibits renin release

Question 22

explain the effect of dehydration on arterial pressure

Answer 22

decreased CO b/c preload decreases which decreases SV
TRP increases b/c the rest of the arterioles constrict to minimize fall in arterial pressure and divert blood to essential organs

Question 23

what would the effect of reduced contractility have on ESV and systolic ventricular pressure

Answer 23

both would increase

Question 24

explain the cause of fluid retention and peripheral edema / pulmonary congestion in heart failure

Answer 24

reduced blood flow during heart failure activates neurohormonal systems (renin, angiotensin II, aldosterone, ADH) which cause fluid retention

increased capillary hydrostatic pressure favors filtration which causes pulmonary congestion and peripheral edema

Question 25

how do skeletal muscles help maintain venous return and cardiac output during exercise

Answer 25

by compressing underlying veins in order to increase blood flow back to the heart (skeletal muscle pump)

Question 26

where are alpha receptors located

Answer 26

in the cell membranes of smooth muscle cells in all arterioles and veins of abdominal organs

Question 27

what is the effect of activation of alpha receptors by NE

Answer 27

vasoconstriction
increased TPR
increase in arterial blood pressure

Question 28

where are B2 receptors found and what is the effect of them being activated by NE/Epi

Answer 28

found on arterioles in coronary circulation and skeletal cells

activation of B2 causes relaxation of vascular muscle and dilation of the arterioles

Question 29

what type of edema can right ventricle heart failure lead to

Answer 29

system edemas in the abdominal organs
- peripheral edema
- ascites (fluid in peritoneal cavity)

Question 30

what type of edema can left ventricle heart failure lead to

Answer 30

pulmonary edema
- pleural effusion