heart failure

Question 1

What is heart failure

Answer 1

A state where the heart fails to maintain an adequate CO to meet the demands of the body

Question 2

What is the equation

Answer 2

CO=HR*SV

Question 3

What is preload

Answer 3

The degree of stretching of the cardiomyocytes at the end of diastole prior to the next contraction and it is dictated by venous return.

Question 4

What is afterload

Answer 4

the resistance against which the ventricles contract to eject blood

Question 5

What factors affect preload

Answer 5

Venous tone, the volume of circulating blood and decreases with blood volume loss and vasodilation.

Question 6

What is the frank starling law

Answer 6

An increase in the volume of blood filling the heart stretches the heart muscle fibres which causes greater contractile forces which, in turn, increases the stroke volume. This is true only up to a certain point.

Question 7

What is low output HF

Answer 7

due to systolic or diastolic HF

Question 8

What is high output HF

Answer 8

Occurs in the context of other medical conditions which increases the demands on the CO.
The heart itself is functioning normally but cannot keep up with the high demand for blood to one or more organs in the body, e.g. pregnancy, sepsis

Question 9

What are the causes of systolic HF

Answer 9

Ischaemic injury
volume overload
pressure overload

Question 10

What are the causes of diastolic HF

Answer 10

Sig left ventricular hypertrophy
infiltrative disorders
constrictive pericarditis
restrictive cardiomyopathy

Question 11

What is systolic HF and diastolic HF

Answer 11

Progressive deterioration myocardial contractile function.
Diastolic HF is the inability of the heart chamber to relax, expand and fill sufficiently during diastole to accommodate an adequate blood volume.

Question 12

What are the causes of HF

Answer 12

CHD, hypertensive HD, vascular HD, myocardial HD, congenital HD.

Question 13

What is a cardiomyopathy

Answer 13

Diffusion disease of the heart muscle leading to functional impairment.

Question 14

What are the 3 types of cardiomyopathy

Answer 14

Dilate cardiomyopathy
hypertrophic cardiomyopathy- affects young people and athletes (hereditary)
restrictive cardiomyopathy- almost impossible to treat

Question 15

What are the types of HF

Answer 15

Left side, right side and biventricular failure
acute or chronic HF
compensated and decompensated HF

Question 16

What are the causes of LSHF

Answer 16

cant get blood out of the LA so it backs up to the pulmonary circulation which leads to pulmonary oedema
causes: IHD, hypertension, VHD and myocardial disease.

Question 17

What does LSHF lead to

Answer 17

increase in breathlessness, increase in orthopnoea (breathlessness lying flat) and dyspnoea (extreme attacks at night, bordering suffocation).

Question 18

How does LVF affect the kidneys?

Answer 18

A decrease in renal perfusion activated the RAAS which in turn increases salt and water retention which increase blood volume which in turn increases BP.

Question 19

Outline causes of RHF

Answer 19

a common cause is LHF, VHD and CHD

Question 20

What are the systemic effects of RHF

Answer 20

congestive splenomegaly, ascites, peripheral oedema and congestive hepatomegaly

Question 21

What are clinical presentations of HF

Answer 21

Dyspnoea, orthopnoea, oedema, hepatic congestion, ascites

due to a reduction in CO
Fatigue and weakness

Question 22

What are clinical signs of cardiac failure

Answer 22

cool, pale, tachycardia, elevated JVP, displaced apex, peripheral oedema, ascites and hepatomegaly

Question 23

What are clinical tests in HF

Answer 23

ECG, blood investigations, echocardiogram, coronary angiography

Question 24

Current drug treatment for HF

Answer 24

ACEi, aldosterone antagonists and ARBs, beta-blockers, SA node blockade and diuretics

Question 25

What is the effect of loop diuretics and give an example

Answer 25

Frusemide: inhibits sodium reabsorption in the PCT, decreased absorption of potassium in the DCT

Question 26

What is an example of an ACE inhibitor and what do they do

Answer 26

Ramipril: decreases the RAAS which leads to vasodilation, decreased BP and less cardiac work.

Question 27

What is an example of a beta-blocker and what do they do

Answer 27

bisoprolol: decrease HR and BP, blocks the action of adrenaline and noradrenaline.

Question 28

Give an example of a SA node blockade and its effects

Answer 28

blocks a channel in the SA node and decreases HR, causes bradycardia and a visual aura.