Cardio - Chf

Front 1

What is low output heart failure?

Back 1

Decreased cardiac output

Front 2

What causes congestion?

Back 2

Pathologic elevation of preload
- fluid retention
- venous vasoconstriction

Front 3

What is high output heart failure?

Back 3

Increased cardiac output - but increased blood flow demand from tissues, or decreased oxygen carrying capacity

Front 4

How would you develop LCHF due to mitral valve insufficiency?

Back 4

Left ventricle would need to eject more blood to keep up with the right ventricle

Front 5

Increased left ventricular preload is synonymous with what?

Back 5

pulmonary venous congestion

Front 6

What are 4 causes of LV volume overload?

Back 6

1. mitral insufficiency
2. aortic insufficiency
3. VSD
4. PDA
All of these result in a decrease SV so the heart will compensate by increasing preload so that SV can equal that of the RV

Front 7

What are 3 causes of RV volume overload?

Back 7

1. tricuspid regurgitation
2. pulmonic regurgitation
3. atrial septal defect

Front 8

What causes pressure overload of the LV?

Back 8

Aortic stenosis
Systemic hypertension

Front 9

What are the results of pressure overload of the LV?

Back 9

Heart needs to generate excessive high pressure to maintain forward CO
Concentric hypertrophy - relative ischemia, loss of compliance, dysdynamic myocardial failure
Compensatory mechanisms - abnormal loading, high HR, autonomic imbalance - pulmonary congestion

Front 10

What are common causes of pressure overload of RV?

Back 10

Heartworm - anything that elevates pulmonary pressure
LCHF - pulmonary congestion causes RV pressure overload

Front 11

What is the result of RV pressure overload?

Back 11

loss of compliance, RV concentric hypertrophy, muscular outflow obstruction

Front 12

What are the causes and clinical signs of myocardial disease that cause loss of inotropy?

Back 12

toxic, metabolic, viral, genetic etc
LCHF and RCHF - Left predominates

Front 13

What type of disfunction results from myocardial diseases which cause loss of inotropy or loss of compliance?

Back 13

Inotropy = systolic
Complaince = diastolic

Front 14

What is the prototypical example of a myocardial disease that causes loss of inotropy OR loss of compliance?

Back 14

Inotropy - Idiopathic dilated cardiomyopathy
Compliance - hypertrophic cardiomyopathy

Front 15

What is the role of the SNS in heart failure?

Back 15

1. Compensatory - Diminished distention of arterial, thoracic baroreceptors of the carotid sinus and great vessels activates SNS
2. Maladaptive - b receptors down regulated, increased myocardial O2 consumption, depleted catecholamines and increased NE

Front 16

How does the PNS contribute to heart failure?

Back 16

PNS efferent withdrawal - increased HR and HR variability
Normally baroreceptors decrease SNS and increase PNS in response to high pressure - blunted in CHF

Front 17

What are three stimulators for renin release?

Back 17

1. decreased renal afferent arteriole distention
2. increased renal sympathetic stimulation
3. decreased Na+

Front 18

What are 5 effects of angiotensin on the heart?

Back 18

1. catecholamine release
2. increased inotropy
3. cardiac vasoconstriction
4. impaired diastolic relaxation
5. myocyte hypertrophy

Front 19

What are 4 effects of ANF?

Back 19

1. Kidney - increase GFR - diuresis, natriuresis
2. suppresses aldosterone + ADH
3. coronary vasodilation
4. sympathoinhibitory effect

Front 20

What happens to ANF in CHF?

Back 20

First it is elevated by atrial distention
Eventually heart is unresponsive to ANF

Front 21

What is the most important feature of BNF?

Back 21

Can be used as a biomarker for CHF

Front 22

What are 3 stimulants for AVP release?

Back 22

1. increase osmolarity
2. decreased BP
3. decreased blood volume

Front 23

What happens to AVP in CHF?

Back 23

Activated in severe CHF by nonosmotic mechanisms - retention of water, hyponatremia, hypochloremia

Front 24

What does the plasma ET level tell you about CHF?

Back 24

Correlates HF functional class + severity of pulmonary hypertension

Front 25

What are 3 functions of ET?

Back 25

1. vasoconstriction
2. positive inotrope - causes reflex bradycardia
3. neuroendocrine release - ANF, PGs, renin, aldosterone, AVP

Front 26

Name stimulators of ET release.

Back 26

ATII, EPI, AVP, Thrombin, IL1, OFR, TGF-B

Front 27

What might be a contributory factor to cardiac cachexia in late stage CHF?

Back 27

TNF

Front 28

Why does hypertrophy of heart occur? What are different types that occur?

Back 28

compensatory -return forces needed to be generated by the myocardium to normal
Volume overload - dilation of heart w/ proportional ventricular wall thickness
Pressure overload - dysproportional ventricular hypertrophy

Front 29

What are 3 consequences of hypertrophy?

Back 29

1. myocardial failure - muscle dysfuction = HF
2. coronary insufficiency - coronary can't keep up demand by myocardium
3. increased preload - decrease compliance makes increase preload necessary

Front 30

How does the kidney response to high ATII levels?

Back 30

vasoconstriction of efferent arteriole - decrease blood flow, peritubular capillary pressure, increased capillary pressure, GFR, fluid resorption

Front 31

What are the levels of ATII and aldosterone in CHF? What is the result?

Back 31

abnormally increased
decreased ability to excrete Na+

Front 32

What are 3 reasons peripheral vascular resistance increases in CHF?

Back 32

1. increased sympathetic tone
2. increase in circulating vasoconstrictor neurohormones
3. impaired NO

Front 33

What are three results of venous vasoconstriction?

Back 33

1. elevation of venous pressure
2. increased cardiac preload
3. increased CO

Front 34

What is the result of pathologic elevation in venous pressure?

Back 34

Definition of congestion!
Organ dysfunction, damage, edema

Front 35

What are 5 consequences of LCHF?

Back 35

1. pulmonary congestion
2. increased pulmonary vessel size
3. interstitial then alveolar pulmonary edema
4. pleural effusion (in cat - drained by visceral pulmonary lymphatics)
5. Respiratory problems - orthopnea, nocturnal dyspnea, cardiac asthma

Front 36

What is Cheyne-Stokes respiration?

Back 36

alternating phates of apnea and hyperventilation - lengthening of circulation time between lungs and respiratory centers due to decreased CO

Front 37

How can LCHF be diagnosed?

Back 37

cardiac catheterization - elevation of pulmonary venous pressure

Front 38

What is the cardinal feature of RCHF?

Back 38

Systemic venous engorgement

Front 39

What are 3 clinical signs of RCHF?

Back 39

1. jugular venous distention
2. hepatomegaly/splenomegaly
3. ascites, pleural effusion, pericardial effusion