6- Pathophysiology of Congestive Heart Failure

Question 1

define heart failure

Answer 1

inability of heart to meet metabolic demands of body

Question 2

classic 3 symptoms of heart failure

Answer 2

dyspnea, increased fatigue, and fluid accumulation

Question 3

structural abnormality of cardiac tissue

Answer 3

cardiomyopathy

Question 4

New York Heart association CHF classification

Answer 4

1-4 with 4 worst = symptoms at rest

Question 5

HF with preserved ejection fraction

Answer 5

compensated heart failure

Question 6

heart failure with low ejection fraction (40%) =

Answer 6

cardiac congestion

Question 7

cardiac congestion =

Answer 7

more volume staying in the ventricular chamber with each heart beat

Question 8

causes of cor pulmonale (right HF)

Answer 8

• vascular dysfunction
• hypoxia
• parenchymal disease within lungs
• left heart failure

Question 9

how does left heart failure cause right heart failure

Answer 9

severe left-sided congestion results in right sided dysfunction as pulmonary edema and pulmonary venous pressure alter the afterload of the right heart

Question 10

compensatory mechanism to offset reduction in stroke volume

Answer 10

ventricular hypertrophy

Question 11

maladaptive consequences of ventricular hypertrophy

Answer 11

• regurgitation
• calcium contractiity imbalance
• increased metabolic demand of myocardium

Question 12

cochanges in calcium cycling imparis…

Answer 12

contractiona nd relaxation of myocytes

can contribute to exercise intolerance because the heart is functionally unable to match increased demand

Question 13

the _________ nervous system is activated in HF. the ________ is defective

Answer 13

symp activated

para defective

• this increases peripheral vascular resistance

Question 14

the _______- reflex is blunted while the _________ is augmented

Answer 14

baroreflec is blunted (an inhibitory reflex) and teh chemoreflex (excitatory) is augmented

Question 15

why is treament with beta adrenergic blockers beneficial in HF

Answer 15

because the receptors are desensitized leading to a decreased response to adrenergic stimualtion

Question 16

compensatory processes try to mitigate the reducation in SV by…

Answer 16

increasing preload (by increasing venous return) and also increasing contractility of heat

Question 17

hwo does vasodilator treatment help with HF?

Answer 17

redues afterload, so the heart can eject a larger SV

Question 18

does diastolic dysfunction happen right away in HF?

Answer 18

no - occurs with time as hypertrophy and other remodeling compromise ventricular relaxation

Question 19

true or false: disatolic dysfunctioin reduces stroke volume

Answer 19

FALSE

not at first at least, it generates higher diatolic pressures within the ventricles which can lead to impaired filling

Question 20

central venous pressure is _________– in HF

Answer 20

elevated

Question 21

target of diuretic HF treatment

Answer 21

reduce volume

Question 22

target of ACEi, ARB

Answer 22

reduce remodeling, afterload, myocardial metabolic demand

Question 23

target of beta blocker

Answer 23

counter sympathetic effects

Question 24

target of statins

Answer 24

dyslipidemia and pleiotropic effects

Question 25

(equation) ejection fraction =

Answer 25

SV/ EDV

Question 26

what part of RAAS is associated with vasoconstriction, hypertrophy, proliferation and increases in hormones, salts?

Answer 26

AT1

inflammation, growth, vasoconstriction, thrombosis

Question 27

what part of RAAS is associated with aldosterone and heart structue and kidney changes?

Answer 27

ATII

fibrosis, electrolyte imbalance, heart faiulre

Question 28

3 compensations for systolic dysfunction

Answer 28

1. increase preload
2. increase contractility (symp)
3. ventricular hypertrophy, elasticity

Question 29

• decreased tissue compliance
• increased passive stiffness
• delayed myocyte relaxation
• depressed ATP levels
• diastolic calcium leak

Answer 29

diastolic dysfunction

HF

Question 30

ventricular hormone released in response to strecth

Answer 30

b type natriutetic peptide

can differentiate from pulmonary failure