Pathophys of Heart Failure - HF 1

Question 1

heart failure most commonly characterized by

Answer 1

• fluid retention

- elevations in ventricular filling pressures

Question 2

some causes of heart failure

Answer 2

• hypertension
• MI
• cardiomyopathy
• arrhythmia
• congenital heart disease
• valvular disease

Question 3

the true problem from heart failure results from

Answer 3

• maladaptive neurohormonal responses to decreased cardiac performance

Question 4

pathophys causes of heart failure

Answer 4

• impaired contractility
• increased afterload
• increased volume
• impaired ventricular filling

Question 5

impaired contractility caused by

Answer 5

• ischemic and dilated cardiomyopathy

Question 6

increased afterload caused by

Answer 6

• longstanding hypertension

- aortic stenosis

Question 7

increased volume caused by

Answer 7

• aortic/mitral insufficiency

Question 8

impaired ventricular filling caused by

Answer 8

• hypertrophy

Question 9

what is the most common cause of heart failure

Answer 9

• MI

Question 10

ischemic cardiomyopathy - the primary/secondary disease process

Answer 10

• primary - coronary arteries

- secondary - heart muscle

Question 11

dilated cardiomyopathy - the primary disease process

Answer 11

• primary - heart muscle

Question 12

decreasing contractility has what effect on stroke volume

effect on cardiac output

Answer 12

• decreasing contractility decreases stroke volume

- decreased cardiac output

Question 13

physiological adaptations to decreased stroke volume

Answer 13

• increased preload (frank starling)

- increased wall thickness

Question 14

what happens if we increase preload beyond that of the adaptive response

Answer 14

• we get pulmonary edema

Question 15

most common symptoms of heart failure

Answer 15

• dyspnea

Question 16

how is preload regulated

Answer 16

• venous tone
• blood volume
• body position

Question 17

venous tone is regulated by

Answer 17

• sympathetic activity increasing tension in walls of veins and venules

Question 18

blood volume increased by

Answer 18

• RAS
• Sympathetic nervous system
• ADH
• fluid intake

Question 19

result of increased sympathetic tone

Answer 19

• beta 1 stimulation increases HR and contractility
• alpha 1 stimulation increases venous return and decreases venous compliance
• increased renin release, salt and fluid retention and vasoconstriction

Question 20

cardio response to chronic beta-AR stimulation

Answer 20

• down regulation of beta AR
• energy starvation
• cardiomyocyte death
• ventricular arrhythmias
• fibrosis

Question 21

RAAS response to decreased stroke volume

Answer 21

• kidneys sense decreased EABV
• increase renin from JGA
• increase angiotensin II and aldosterone levels
• increases blood volume and vasoconstriction

Question 22

heart failure result on RAAS

Answer 22

• disrupts negative feedback loop

- excessive fluid retention

Question 23

role of ANP and BNP

Answer 23

• counteract maladaptive hormones

Question 24

how chronic hypertension leads to heart failure

Answer 24

• chronically elevated BP increases LV pressure
• leads to hypertrophy of ventricle
• remodeling and dilation

Question 25

effect of chronic hypertension and aortic stenosis on afterload

Answer 25

- increase afterload

Question 26

what is the easiest component of afterload to modify

Answer 26

- systemic vascular resistance

Question 27

myocyte impact in pathological hypertrophy - what type of hypertrophy

Answer 27

- increase myocyte width | - concentric hypertrophy

Question 28

myocyte impact in cardiac dilatation - what type of hypertrophy

Answer 28

- increase myocyte length | - eccentric hypertrophy

Question 29

what defines pathologic remodeling

Answer 29

- fibrosis

Question 30

impact of fibrosis on the heart

Answer 30

- impairs ability to contract and relax | - leads to heart failure

Question 31

effect on a dilated and remodeled heart on afterload

Answer 31

- increases afterload

Question 32

2 mechanism that increase afterload contributing to heart failure

Answer 32

- ventricular remodeling and dilatation leading to increased volume - increased SVR in response to low stroke volume

Question 33

result of chronically high afterload

Answer 33

- leads to decreased stroke volume and heart failure

Question 34

contractility, stroke volume and preload with heart failure

Answer 34

- decreased contractility - decreased stroke volume - increased preload

Question 35

pressures in diastolic dysfunction

Answer 35

- stiff ventricle - high ventricular pressure leading to increased left atrial pressure - causes pulmonary edema

Question 36

contractility, stroke volume, and stiffness in systolic dysfunction

Answer 36

- decreased contractility - decreased stroke volume - increased stiffness

Question 37

contractility, stroke volume, and stiffness in diastolic dysfunction

Answer 37

- normal contractility - decrease stroke volume - increased stiffness

Question 38

pressure/volume effect on heart failure

Answer 38

- heart failure develops due to high LVEDP/left atrial pressure at low volume

Question 39

effect of ANP released by

Answer 39

- vasodilator - increase salt output in urine - released by atrial myocytes

Question 40

effect of BNP released by

Answer 40

- also counters RAAS | - released by ventricular myocytes

Question 41

what lab test can we use to diagnose heart failure?

Answer 41

- check BNP levels - if high, means heart failure - if low, dyspnea is due to some other thing