Session 9 Flashcards

(73 cards)

1
Q

What is heart failure?

A

A state in which the heart fails to maintain an adequate circulation for the needs of the body despite an adequate filling pressure

Failure of the pump action of the heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the primary cause of systolic heart failure?

A

ISCHAEMIC HEART DISEASE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Apart from ischaemic heart disease, what are some other causes of heart failure?

A
Hypertension 
Dilated cardiomyopathy 
Valve disease
Pericardial disease
Arrhythmias - e.g. persistent tachycardia 
High-output heart failure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What happens in high-output heart failure?

A

Heart can’t keep up with the amount of cardiac output the body needs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How can arrhythmias (persistent tachycardia) cause heart failure?

A

Persistent tachycardia —> Changes in structure of the heart —> Failure of pump action —> Heart failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How is heart failure progression classified by the NYHA functional classification?

A

Class I - Class IV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

In which classes of the NYHA functional classification of heart failure is there no symptoms at rest?

A

Classes I-III (class IV may have symptoms at rest)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Heart failure is classified by the NYHA functional classification based on the occurrence/absence of symptoms due to different levels of…

A

Physical activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the typical…

I) cardiac output 
II) stroke volume
III) LV ESV
IV) LV EDV 
V) Ejection fraction
A

5 litres/min

75 ml/beat

75 ml

150 ml

50% +

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

State 4 factors influencing cardiac output

A

Heart Rate
Venous Capacity (LV preload)
Aortic & Peripheral Impedance (afterload)
Myocardial Contractility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How can heart rate affect cardiac output?

A

Increasing heart rate, increases cardiac output up until a certain point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What functional and structural changes are seen in left ventricular systolic dysfunction?

A

Increased LV capacity —> Reduced LV cardiac output

Thinning of the myocardial wall (fibrosis/necrosis)
LV dilated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How can left ventricular systolic dysfunction affect the mitral valve?

A

LV dilation leads to cusps of valves being pulled apart and incompetence of the mitral valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the structural heart changes seen in heart failure (3)

A

Loss of muscle
Changes to the ECM (increased type III collagen)
Change of cell structure/function (e.g. Myocyte hypertrophy)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How can the structural heart changes seen in heart failure affect myocardial contraction?

A

Results in uncoordinated/abnormal myocardial contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the ventricular remodelling that occurs in…

I) diastolic heart failure
II) systolic heart failure

A

Hypertrophied heart

Dilated heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe the ventricular remodelling seen after acute infarction

A

Global remodelling and scarring to protect damaged areas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe the early role of the sympathetic nervous system (baroreceptor-mediated response) in heart failure

A

Works to improve cardiac output by increased contractility, HR (tachycardia) and arterial and venous vasoconstriction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What long term deleterious effects can activation of the sympathetic nervous system in heart failure have?

A

B-adrenoceptors become down-regulated/uncoupled
Noradrenaline induces cardiac hypertrophy, apoptosis and necrosis via a-adrenoreceptors
Noradrenaline induces up-regulation of the RAAS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

State long term deleterious effects of activation of the sympathetic nervous system in heart failure, with regards to the increased noradrenaline levels

A

Induces cardiac hypertrophy, myocyte apoptosis, myocyte necrosis via a-adrenoreceptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How can sympathetic nervous stimulation (in the long term) seen in heart failure affect the variability of the heart rate

A

Reduction in heart rate variability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Where is angiotensinogen produced?

A

Liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Angiotensinogen is clever to _______________ by the action of __________

A

Angiotensin I

Renin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Angiotensin I is clever to __________________ by the action of ___________________

A

Angiotensin II

ACE - angiotensin converting enzyme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Angiotensin I and II can both be used to produce angiotensin III by the action of...
NEP
26
Angiotensin II carries out its effects via which receptors?
``` AT1 receptors (type 1) AT2 receptors (type 2) ```
27
Which receptors does angiotensin III act on?
Type 2 receptors
28
Which angiotensin II receptors lead to more beneficial effects for a patient?
Type 2 receptors
29
What effect can activation of the angiotensin II receptors have?
Vasodilator effect by increasing NO levels
30
Nitric oxide is a powerful _________________
Vasodilator
31
Name three deleterious effects of angiotensin II binding to type 1 receptors
Vasoconstriction ---> Increased afterload ---> Decreased CO ---> Stroke/Hypertension LV hypertrophy ---> Fibrosis/Remodelling ---> HF/MI Aldosterone release ---> Increased salt/water retention ---> Renal failure
32
Angiotensin II results in the release of ____________ which results in increased salt/water retention
Aldosterone
33
Why is the RAAS commonly activated in heart failure?
Reduced renal blood flow (perfusion pressure) in the kidneys
34
Atrial natriuretic peptides respond to _________ due to increased ____________
Stretch Volume
35
What effect do natriuretic hormones have? (4)
Constricts afferent arterioles VASODILATOR of efferent arterioles Decreases Na+ reabsorption in the collecting duct Inhibits secretion of renin/aldosterone
36
Where is brain natriuretic peptide produced? Where is atrial natriuretic peptide produced?
Ventricular myocytes (in the brain also) Atrial myocytes
37
Natriuretic peptides work to lower the blood pressure and work carried out by the heart by reducing...
The volume of blood
38
What can be used as a sensitive marker for heart failure?
Natriuretic hormones
39
Name two things that can result in hyponatraemia (water in excess of Na+ retention) in normal conditions
Increased water intake (thirst) | Action of ADH on V2 receptors in collecting duct
40
ADH acts on which receptors in which part of the kidney?
V2 receptors Collecting duct
41
Normally hyponatraemia _________ ADH release but ADH is ______________ in heart failure
Inhibits Increased
42
How can the increased ADH seen in heart failure affect water retention and cardiac output?
Increased water retention | Increased systemic resistance ---> Reduced cardiac output
43
Endothelial is secreted by...
Vascular endothelial cells
44
What effects does endothelin released from vascular endothelial cells have? By which mechanism does endothelin communicate with vascular endothelial cells?
VASOCONSTRICTOR effect Autocrine activity Activating the RAAS
45
Describe the changes in levels of endothelin you may see in a patient with heart failure
Increased endothelin in HF
46
What effect can prostaglandins E2 and I2 have? What are they stimulated by?
VASODILATORS on afferent renal arterioles Noradrenaline/RAAS
47
Nitric oxide is a potent ________________ produced by ________________ cells by the action of...
Vasodilator Endothelial Nitric oxide synthase
48
How can NO synthase be affected in heart failure? What effect does this have?
Reduced activity in heart failure Loss of vasodilation
49
What does bradykinin promote? (2)
Natriuresis | Vasodilation
50
Bradykinin stimulates the production of...
Prostaglandins
51
Describe the levels of tumour necrosis factor seen in heart failure. What effect can these have on the heart?
Increased in HF Represses myocardial function
52
What symptom is a tell-tale sign of heart failure?
Oedema
53
What is oedema?
Excessive volume of fluid within the tissues in the interstitium an intracellularly
54
Net filtration pressure = ...
Hydrostatic pressure - osmotic pressure
55
How does heart failure affect net filtration pressure and cause oedema?
Increased capillary hydrostatic pressure ---> Increased net filtration pressure More fluid into the interstitium
56
How is skeletal muscle blood flow affected in heart failure? What consequence can this have on skeletal muscle mass? What symptoms can this result in?
Reduced Reduction in skeletal muscle mass Fatigue Exercise intolerance
57
Diastolic HF is a less common form of heart failure. What is another name for it? In which patients is it more common?
Heart Failure with Preserved Ejection Fraction Elderly + Women
58
In diastolic heart failure there is ___________ LV function with ______________ remodelling
Normal Concentric
59
What happens in heart failure with preserved ejection fraction?
Reduced LV compliance and impaired myocardial relaxation. Impaired diastolic LV filling. LV filling becomes dependent on high LA pressure. RV dysfunction can result from high LA/PA pressure.
60
What can result from the high LA/PA pressures seen in diastolic heart failure?
RV dysfunction
61
In diastolic heart failure, LV filling becomes dependent on...
High LA pressure
62
Describe what happens to cardiomyocytes in diastolic heart failure. What causes a reduced LV compliance in diastolic HF?
Thicker and shorter cardiomyocytes - impaired relaxation Increased deposition of collagen
63
In diastolic HF there is impaired...
Diastolic LV filling
64
State 4 common symptoms of left sided heart failure
``` Fatigue Exertional dyspnoea Orthopnea Paroxysmal nocturnal dyspnoea Tachycardia Cyanosis ```
65
What is dyspnoea? What is orthopnea? What is paroxysmal nocturnal dyspnoea?
Shortness of breath Shortness of breath when lying flat Attacks of shortness of breath at night
66
What is the name given to failure of both sides of the heart (ventricles)?
Biventricular (congestive) cardiac failure
67
Describe the term given to heart failure due to... I) 'pump failure' II) 'failure of LV relaxation)
Left ventricular systolic dysfunction Heart failure with preserved ejection fraction
68
Right sided heart failure is often secondary to... Can also result from...
Left sided heart failure Chronic lung disease, PE, pulmonary hypertension
69
Right sided heart failure results in fluid accumulation in areas drained by systemic veins. State some symptoms of RSHF.
``` Fatigue Dyspnoea Nausea Anorexia Weight Gain DEPENDENT PITTING OEDEMA Enlarged liver/spleen Visible jugular vein ```
70
What is heart failure?
Where the heart fails to maintain an adequate circulation for the needs of the body despite an adequate filling pressure
71
What is chronic heart failure?
Clinical syndrome caused by abnormality of the heart and recognised by a characteristic pattern of renal, neural and hormonal responses
72
Heart failure incidence is ______________ while prevalence is ____________
Decreasing Increasing
73
Give an example of a mineralocorticoid receptor antagonist. How do they work?
Spironolactone Acts as a competitive inhibitor for aldosterone receptors