Pathology 2: Heart Failure

Question 1

Heart is similar to a pump, it’s composed of what components

Answer 1

1. Control components
2. Distribution components

Question 2

What are the control components

Answer 2

1. Myocardium
2. Valves
3. Conductive system

(Structure of the heart)

Question 3

What are the distribution components

Answer 3

1. Systemic circulation
2. Pulmonary circulation

Question 4

How does heart failure develops

Answer 4

Gradually and insidiously due to cumulative effects of disorders of various etiology

Question 5

CO depends on what

Answer 5

SV x HR

Question 6

What is SV

Answer 6

Amount of blood ejected from ventricle during systole

Question 7

What is the equation of SV

Answer 7

SV = EDV-ESV

Question 8

SV depends on what

Answer 8

1. Preload
2. After load
3. Myocardial contractility

Question 9

What is preload

Answer 9

• It’s the amount of blood ready to be pumped by the ventricle
• ventricular pressure at the end of diastole
• after the filling

(Same definition)

Question 10

What is after load

Answer 10

• Pressure during ventricular systolic contraction
• during ejection of blood

Question 11

What will happen to preload in heart failure

Answer 11

Decreased

Question 12

What happens to after load in heart failure

Answer 12

Increased

Question 13

When will SV increase

Answer 13

1. Increase in preload
2. Decrease in after load
3. Enhanced contractility

Question 14

What are the onset of heart failure

Answer 14

1. Acute
2. Chronic (congestive HF) (more common)

Question 15

What are the sides involved in heart failure

Answer 15

Left and right side

Question 16

What are the causes of left sided heart failure

Answer 16

1. Hypertension
2. Ischemic heart disease
3. Aortic stenosis
4. Moral incompetence

(1&2 are the most common)

Question 17

How can ischemia causes heart failure

Answer 17

Atherosclerosis of coronary arteries =

less blood supply to cardiac muscle =

chronic ischemia of cardiac muscle

Question 18

How can aortic stenosis causes heart failure

Answer 18

Narrowed aortic valve

= left ventricle will eject blood against increased resistance

= eventually will fail

Question 19

How does mitral incompetence causes heart failure

Answer 19

Mitral valve isn’t closing properly

= back flow of blood during systole from left ventricle into left atrium

= left sided failure

Question 20

What are the causes of right sided heart failure

Answer 20

1.COPD
2. LSHF (most common)
3. Pulmonary stenosis
4. Tricuspid stenosis

Question 21

How can LSHF causes RSHF

Answer 21

When left side fails = pressure increase = blood accumulate in pulmonary congestion = pulmonary hypertension = edema = RSHF

Question 22

How can COPD causes RSHF

Answer 22

any condition causes pulmonary fibrosis = fibrosis will cause pressure on pulmonary vasculature = pulmonary hypertension

Question 23

What are the physiological compensatory mechanism

(Like exercising,etc)

Answer 23

1. Dilation (to pump more blood)
2. Increased heart rate

Question 24

What is compensatory mechanism when there’s a pathological conditions

Answer 24

1. Increased HR
2. Dilation
3. Hypertrophy
4. Neuro-hormonal (RAAS)

Question 25

What is the mechanism of dilation

Answer 25

Increased ventricle size = increase contraction force

Question 26

What is the type of dilation in physiological condition

Answer 26

Active dilation (The ventricle aren’t forced to dilate)

Question 27

What is the type of dilation in pathological condition

Answer 27

Passive dilation

Question 28

What is the end result of passive dilation

Answer 28

= gradual decrease of contraction force = strength of muscular contraction decrease = incomplete emptying

Question 29

What happens when there’s increased heart rate in pathological conditions

Answer 29

The heart cannot empty it’s content completely = no sufficient time for complete emptying

Question 30

What is the end result of hypertrophy

Answer 30

Muscles become too big for blood supply & nutrients = incomplete emptying = further heart failure = more dilation

Question 31

What is the neurohormonal response in heart failure

Answer 31

= low CO = + SNS & +RASS = vasoconstriction + water & salt retention = further stress on the failing heart = further heart failure

Question 32

What are the effects of heart failure

Answer 32

1. Forward effects 2. Backward effects - impaired tissue perfusion - venous congestion - Edema

Question 33

What are the effects of LSHF

Answer 33

1. Impaired tissue perfusion 2. Pulmonary congestion & Edema

Question 34

What are the effects of RSHF

Answer 34

1. Low output to lungs (insignificant unless due to LSHF) 2. Systemic venous congestion 3. Generalised Edema

Question 35

What type of effects are more significant in RSHF

Answer 35

Backward effect

Question 36

What are the causes of chronic HF

Answer 36

1. Hypertension 2. Ischemic heart disease 3. COPD 4. Valve disease 5. Severe anemia

Question 37

What are the effects of chronic HF

Answer 37

1. Fully developed compensatory mechanism 2. Generalised venous congestion 3. Generalised Edema

Question 38

What are the causes acute HF

Answer 38

1. Coronary occlusion 2. Pulmonary embolism 3. Cardiac tamponade 4. Malignant hypertension 5. Acute mycocarditis

Question 39

What are the effects HF

Answer 39

1. No time for compensatory 2. Multi - organ failure 3. Acute pulmonary Edema