PBL 7 - Heart Failure Flashcards

1
Q
  1. Blood tests on Mr. Williams would include measurement of B-type Natriuretic peptide (BNP). Where does BNP originate and what is the significance of its blood level? (2 marks)
A

BNP is secreted from the ventricles when they are stretched (1 mark). Increased BNP levels in the blood indicate overstretched or enlarged ventricles (1 mark)

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

Explain why Mr. Williams has a raised jugular venous pressure (2 marks)

A

He has right heart failure (1 mark) which means his right heart cannot pump out the blood delivered to it; thus blood and pressure build up in the great veins and venous circulation (1 mark)

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

What imaging tests would Mr. Willams receive? (1 mark) What might the imaging tests show to confirm a diagnosis of heart failure? (2 marks)

A

Chest x-ray and echocardiogram (1/2mark each) echocardiogram would show a dilated, poorly contractile left ventricle. (1 mark) CXR should show heart enlargement (1 mark) and evidence of pulmonary oedema such as Kerley B lines (1 mark)

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

List three classes of drug which would be ‘first line’ therapy for Mr. Williams. Explain the rationale for each drug class. (3 marks)

A

A diuretic (1/2 mark), most likely a loop diuretic such as frusemide (1/2 mark) . This would reduce the venous blood volume and thus preload on the heart, reducing its workload (1/2 mark).

A beta blocker (1/2 mark) could be introduced as long as there is no evidence for metabolic syndrome or type II diabetes in Mr. Houseman. This would also reduce the work of the heart by reducing contractile force (1/2 mark)

An  ACE inhibitor (1/2 mark) will  reduce blood pressure and also reduce sodium retention; this will reduce both preload and afterload on the heart (1/2 mark). Angiotensin receptor antagonists (ARBs) may be used instead of ACE inhibitors, and will have similar  effects (marks for either ACE inhibitors or ARB’s but not both)
A vasodilator  (1/2 mark)  such as isosorbide dinitrate  can be used. This lowers peripheral resistance and reduces the work of the heart  (1/2 mark)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is heart failure (2)

A

When the heart cannot supply enough blood to meet the metabolic demands of the body
Usually due to a reduction in stroke volume
Occurs when the heart becomes enlarged –> less ejection pressure –> lower stroke volume and increased end systolic ventricular volume

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

How is Heart failure diagnosed? (1) (how many minor and major)

A

either 2 major criteria or 1 major and 2 minor criteria.

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

Name 3 major and 3 minor criteria from the Framingham criteria (3)

A
Major
= Paroxysmal nocturnal dyspnea
= Weight loss 4.5kg in 5 days after treatment
= Hepatojugular reflux
= S3 gallop
= Rales (crackles in lungs)
Minor
= Nocturnal cough 
= Dyspnea on ordinary exertion
= Pleural effusion
= Tachycardia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Explain why Mr. Williams was tired, short of breath? (2)

A

left ventricle may be able to pump out
sufficient blood at rest, when the patient takes even mild exercise the cardiac output is
insufficient to supply the metabolic requirements of the exercising skeletal muscles.

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

Explain why were Mr Williams’ ankles swelled? (1)

A
Indicates Right heart failure.
raised central venous pressure disrupting the Starling
Mechanism in the systemic capillaries. 
 worse in the evenings because it is
gravitational in nature.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is pulsus alternans and what does it indicate? (2)

A

alternating strong and weak pulse. It indicates left ventricular
impairment, and could be a sign that aortic stenosis or aortic valve disease is contributing
to the left heart failure.

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

Name 3 abnormalities you could identify in a clinical examination of someone with HF? (2)

A
  • Small pulse volume (reduced ejection fraction)
  • Elevated venous pressure
  • Left ventricular enlargement
  • 3rd and 4th heart sounds
  • Heart murmur due to mild mitral regurgitation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What abnormalities would you see on the echocardiogram and X-ray in HF? (2)

A
X-ray 
- Heart size enlarged
- Pulmonary Oegema
- Interstitial oedema (kerley B-lines)
ECHO
- Dilated, poorly contractile left ventricle (L A dilated)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What surgical treatments could man have? (1)

A

Revascularisation
Valve replacement/repair
Heart transplant

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

What is the non-pharmacological treatment he could have and why is it given? (2)

A

Oxygen

Non-invasive positive pressure ventilation, dietary sodium and fluid restriction, physical activity , weight loss

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

What is the life expectancy of patients with HF and what do they die of? (2)

A
Poor - 50% 5 year mortality
Ventricular arrhythmia (sudden cardiac death)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Causes of heart failure

A

poor left ventricular function

due to ischaemic heart disease, cardiomyopathy or valvular heart disease.

17
Q

What causes right heart failure

A

Right heart failure often
follows on from chronic left heart failure: Pulmonary edema and hypoxia due to left heart
failure causes pulmonary arteriolar constriction and a raised pulmonary arterial pressure.
This in turn puts a strain on the right ventricle which eventually enlarges

The enlarged and
weakened right ventricle has a reduced stroke volume and cannot cope with the volume of
blood (preload) being delivered by the central venous system. The result is a raised central venous pressure.

18
Q

What is congestive heart failure

A

Both sides of the heart are failing

19
Q

What is paroxysmal nocturnal dyspnea

A

Waking up suddenly with a feeling of severe anxiety and breathlessness

20
Q

Why does the patient have tachycardia

A

a sign that the
sympathetic nervous system is attempting to compensate for a reduced stroke volume by
increasing heart rate.

21
Q

What is ejection fraction

A

the amount, or percentage, of blood that is pumped (or ejected) out of the ventricles with each contraction

22
Q

How do you measure CO

A

Heart Rate x Stroke Volume

23
Q

What is compensation in HF

A
o	Compensation (makes it worse)
	Peripheral vasoconstriction - higher resistance – increased failure – decreased perfusion to organs specifically kidneys – activates RAAS – end in fluid retention – increase BP – back up of fluid
24
Q

Left heart failure

A

Unable to contract with enough force

= Pulmonary congestion/oedema, SOB, PND

25
Q

Right heart failure

A

Pumping higher against pressure in pulmonary vessels
(COPD, LVH)
Nutmeg liver, fatigue, weight gain/loss, ascites, enlarged liver, spleet

26
Q

Systolic and diastolic dysfunction

A

 Systolic –ventricular dysfunction– LV ejection fraction <40%
 Diastolic – ventricles fail to fill up adequately – normal ejection fraction due to wall thickness increasing/reduced preload.