Heart failure

Question 1

Most common causes of heart failure?

Answer 1

Iscahemic heart disease

HTN

Valve disease

Shock; insufficient blood flow across body

Question 2

Define heart failure.

Answer 2

When the heart fails to pump blood at a RATE

equal to the requirement of metabolising tissues

Or when the heart can only pump enough at elevated filling pressures

Question 3

CO = HR x SV. What factors influence each of these?

Answer 3

HR - SNS, RAS, NA+A

SV - ventricular dilatation, venous return

Question 4

What are 3 ways the heart changes to different stimuli?

Answer 4

Physiological changes - increasing HR and contractility for exercise

Adaptive changes (compensation)- normal; cell hypertrophy in response to protein synthesis and physiological hypertrophy in response to exercise. both can reverse i.e. when stop exercise.

Non adaptive changes (decompensation) - HF

Question 5

What are the 2 broad categories of causes of heart failure? and the 3 subcategories?

Answer 5

1. LOW OUTPUT;
   Myocardial dysfunction
   Volume/pressure overload
2. HIGH OUTPUT;
   overwork

Question 6

What are the 3 broad categories of things you would find in someone with heart failure

Answer 6

Pathological changes;
non specific and specific features

Molecular changes

Myocardial remodelling (macroscopic)

Question 7

What are some non specific and specific features of heart failure you would see on histology ?

Answer 7

Non specific;
interstitial fibrosis, cell hypertrophy, nuclei changes
(non specific because can be caused by anything)

Specific;
infective agent, amyloid, iron overload
(specific i.e this finding will point to one particular cause or disease)

in other words finding amyloid means that amyloidosis is the cause of the HF etc.

Question 8

What are some molecular changes seen in HF?

Answer 8

Fetal genes - switch from alpha myosin to beta myosin

Production of cytokines and neurohormones by myocytes - lead to auto and paracrine ‘loops’ action which can lead to myocyte damage

Abrnomal protein synthesis - bad excitation contraction coupling.

Question 9

What are 4 examples of myocardial remodelling seen in HF?

Answer 9

Cell hypertrophy

Changes in the ECM - i.e. fibrosis

Myocyte death

Globular heart - makes mechanics of heart sub optimal

• so these are things that arent molecular but can be seen at macroscopic level!

Question 10

What 4 areas of the heart can be affected in Heart disease?

Answer 10

Myocardium
Endocardium
Pericardium
Valves

Question 11

What are 3 patterns of cardiomyopathies?

Answer 11

Dilated pattern - 3 I’s; Inflamation , Infarction, Idiopathic, dystrophies. Most common

Hypertrophic pattern - gym life heart .. HOCM

Restrictive pattern - stiff heart muscles - amyloid, idiopathic

Question 12

Another name for inflammatory cardiomyopathy?

Answer 12

Myocarditis

Question 13

Name the causes, pathogenesis and changes sen on the heart for the different cardiomyopthies?

Answer 13

See lecture

Question 14

What does HOCM stand for?

Answer 14

Familial hypertrophic cardiomyopathy

Question 15

Name 3 types of amyloid involved in causing restrictive cardiomyopathy.

Which conditions are these amyloids usually present?

Answer 15

SA - found in ageing people
senial atrial

Systemic amyloid;
AL - myeloma (haem conditions)

AA - rheumatoid arthiritis (chronic inflam conditions)

Question 16

How do some endocardial disease impact heart function?

Answer 16

Endomyocardial fibrosis - prevents ventricles from contracting properly as endocardium lines inside of heart.

Question 17

Mitral regurgitation causes which type of overload?

Answer 17

Fluid overload of left ventricle

Question 18

Aortic regurgitation causes which type of overload?

Answer 18

Fluid overload of left ventricle

Question 19

Aortic stenosis causes which type of overload?

Answer 19

pressure overload on left ventricle

Question 20

What is one example of congenital heart disease and how can it cause HF?

Answer 20

Ventriculoseptal defect

ventricle pumps at high pressure, blood forced into right ventricle which will hypertrophy due to thin walls - eventual failure

Question 21

Name some extrinsic conditions causing hf?

Answer 21

Pulmonary hypertension

systemic HTN

Question 22

What changes would hypertensive conditions cause on the heart?

Answer 22

systemic htn - left sided HF

Pulmonary htn - right sided hf

Pathological changes - hypertrophy

Question 23

Examples of lung disease leading to pulmonary HTN?

Answer 23

Obstruction/Destruction of pulmonary vessels;

• pulm thromboemoblic disease
• pulm fibrosis

Chronic Hypoxia;

• copd
• cystic fibrosis
• lung fibrosis

Question 24

What are the local complications of heart failure?

Answer 24

Arrhythmias - can lead to sudden cardiac death

Ischaemic damage to myocardium

Question 25

What are the systemic complications of heart failure?

P.S. divide into left and right sided hf

Answer 25

Left sided;

1. Forward failure; Hypoperfusion
2. Backward failure; Pulmonary oedema and overload

Right sided;
1. Forward failure; minor
2. Backward failure;
    A. Systemic oedema
    B. Organ congestion (i.e. nutmeg liver)

Question 26

In a pulmonary oedema caused by HF, which cells would you see in the lungs and why? which stain is used?

Answer 26

Cells filled with iron as a result of micro haemorrhage in lungs due to fluid overload
Pearl stain - detects iron