Cardiac Failure - Acute Heart Failure

Question 1

Acute left ventricular failure (ALVF) occurs when an acute event results in the left ventricle being unable to move blood efficiently through the left side of the heart and into the systemic circulation. What is the incidence of (ALVF)?

1 - 20,000 cases per 100,000
2 - 2000 cases per 100,000
3 - 200 cases per 100,000
4 - 20 cases per 100,000

Answer 1

3 - 200 cases per 100,000

Equally likely in men and women

Question 2

What age does the incidence of acute left ventricular failure (ALVF) typically peak at?

1 - >70
2 - >60
3 - >50
4 - >40

Answer 2

1 - >70

Question 3

Stroke volume (SV) is the volume of blood ejected from the heart per beat. How do we calculate SV?

1 - SVR / EDV
2 - SVR / ESV
3 - EDV - ESV
4 - EDV - EF

SVR = systemic vascular resistance
ESR = end systolic volume
EDV = end diastolic volume
EF = ejection fraction

Answer 3

3 - EDV - ESV

EDV = fully relaxed left ventricle filled with blood
occurring at the end of diastolic filling and heard at S1 closure of mitral and tricuspid valves

ESV = blood remaining in left ventricle after contraction, occurring at the end systole and heard at S2 closure of aortic and pulmonary valves

Question 4

Ejection fraction (EF) is a measure of left ventricular function. How can we calculate EF?

1 - EF = HR x SV
2 - EF = (HR / SVR) x 100
3 - EF = (SV / EDV) x 100
4 - EF = (SV / ESV) x 100

SV = stroke volume
HR = heart rate
EDV = end diastolic volume
ESV = end systolic volume

Answer 4

3 - EF = (SV / EDV) x 100

Normal EF = >55%
- 40-50% is borderline heart failure
- <40% is systolic heart failure

Question 5

The frank starling mechanism is useful to understand the relationship between systolic and diastolic function. What does the frank starling mechanism show?

1 - increased atrium filling means more ventricular contraction
2 - increased ventricular stretching results in greater stroke volume (SV)
3 - increased ventricular stretching results in reduced preload
4 - reduced ventricular filling increased afterload

Answer 5

2 - increased ventricular stretching results in greater stroke volume

• like a rubber band, the more the stretch the ventricle in diastole = a greater contract force and a larger SV in systole
• reduced stretching due to a dilated or weak left ventricle will cause a reduction in the SV

Question 6

All of the following can occur in acute left ventricular failure (ALVF), but which is typically the first sign?

1 - increased LV diastolic pressure
2 - increased end diastolic volume
3 - reduced ejection fraction
4 - reduced SV

Answer 6

4 - reduced SV

• weak heart so decreased left ventricle contractility

Question 7

In acute left ventricular failure (ALVF), stroke volume is decreased due to a weakened left ventricle (LV), causing more blood to remain in is left in the LV at the end of systole. Which of the following can this then cause?

1 - increased left atrium (LA) pressure
2 - increased pulmonary venous pressure
3 - pulmonary oedema
4 - all of the above

Answer 7

4 - all of the above

• More blood in LV means increased pressure in the LA to force blood into LV
• increased pressure in pulmonary veins needed to overcome pressure in LA
• fluid backs up into the lungs causing pulmonary oedema

Question 8

Decompensated chronic heart failure is the leading cause of acute left ventricular failure (ALVF). Which of the following is NOT a typical cause of this?

1 - ACS / IHD
2 - Hypertensive crisis (bilateral renal artery stenosis)
3 - Toxins
4 - Acute arrhythmia
5 - Valvular disease
6 - Iatrogenic (e.g., aggressive IV fluids in a frail elderly patient with impaired left ventricular function)
7 - Sepsis

Answer 8

3 - Toxins

De novo = 1st time
- Typically occurs in patients with no known heart failure, but have other health conditions that damage their heart. Most common is ischaemia that causes increased cardiac filling pressures and myocardial dysfunction

Question 9

De-novo, meaning 1st time occurs in patients with no known heart failure, but have other health conditions that can lead to acute left ventricular failure (ALVF). Which of the following is NOT a typical cause of this?

1 - ACS / IHD
2 - Viral myopathy
3 - Toxins
4 - Valvular dysfunction

Answer 9

1 - ACS / IHD

Question 10

Acute left ventricular failure (ALVF) can cause dyspnoea. Does this then cause type 1 or 2 respiratory failure?

Answer 10

• Type 1 respiratory failure
  Essentially low oxygen
  <8kPa with normocapnia

Question 11

All of the following may be observed during the examination of a patient with Acute left ventricular failure (ALVF), EXCEPT which one?

1 - Bradycardia
2 - Tachypnoea
3 - Hypertension (RAAS activation)
4 - Valvular heart disease with murmur
5 - 3rd heart sound on auscultation
6 - Bilateral basal crackles (pulmonary oedema)
7 - Raised JVP (increased RA pressure)
8 - Peripheral oedema

Answer 11

1 - Bradycardia

Tachycardia is more common

In severe cases ALVF can lead to cardiogenic shock and hypotension

JVP and peripheral oedema are most common in right sided heart failure

Question 12

The following are key symptoms of Acute left ventricular failure (ALVF), EXCEPT which one?

1 - Breathlessness, worse by exertion
2 - RUQ pain and mass
3 - Dry cough (may be frothy white/pink)
4 - Orthopnoea
5 - Paroxysmal nocturnal dyspnoea
6 - Peripheral oedema
7 - Fatigue

Answer 12

2 - RUQ pain and mass
Hepatomegaly is NOT a common symptom

Orthopnoea = breathlessness when lying flat, patients often sleep with lots of pillows

Paroxysmal nocturnal dyspnoea = being woken by the feeling of drowning/severe SOB when asleep

Question 13

Which blood test has the best sensitivity for detecting heart failure early and is now the 1st line test for heart failure?

1 - brain natriuretic peptide (BNP)
2 - troponin
3 - creatine Kinase MB
4 - N-terminal pro b-type natriuretic peptide (NT-proBNP)

Answer 13

4 - N-terminal pro b-type natriuretic peptide (NT-proBNP)

Typically released by left ventricle due to excessive fluid, stretching and strain

• Longer half life so remains in blood for longer
• Better sensitivity to detect heart failure early

Question 14

N-terminal pro b-type natriuretic peptide (NT-proBNP) and brain natriuretic peptide (BNP) are released from the left ventricle in response to heart strain. What do these 2 hormones then do?

1 - signal the heart to slow contractions
2 - reduce ADH release by hypothalamus
3 - reduce aldosterone release by adrenal glands
4 - reduce Na+ and H2O retention in kidney

Answer 14

4 - reduce Na+ and H2O retention in kidney

Question 15

Normal levels of N-terminal pro b-type natriuretic peptide (NT-proBNP) and brain natriuretic peptide (BNP) are:

• NT-proBNP = <400 pg/ml (47 pmol/litre)
• BNP = <100 pg/ml (29 pmol/litre)

High levels = specialist assessment including transthoracic echocardiography <2 weeks

Raised levels = specialist assessment including transthoracic echocardiography <6 weeks

Answer 15

Referral is based on NT-proBNP = <400 pg/ml and BNP levels

Very high NT-proBNP and BNP = poor prognosis

Question 16

N-terminal pro b-type natriuretic peptide (NT-proBNP) and brain natriuretic peptide (BNP) are sensitive (confirm presence of disease) to heart failure, but are they specific (rule out disease in those who do not have it)?

Answer 16

• No

NT-proBNP and BNP can be raised in:
- Tachycardia
- Sepsis
- Pulmonary embolism
- Renal impairment
- COPD

Question 17

ECGs can provide information about patients with heart failure. Which of the following traits is NOT commonly observed?

1 - Tall complexes (‘LV hypertrophy’)
2 - narrow QRS complexes (‘Left bundle branch block’)
3 - T wave inversion
4 - Tachycardia

Answer 17

2 - narrow QRS complexes (‘Left bundle branch block’ (LBBB)

Typically causes broad QRS complex common in LBBB

• Tachycardia = aims to increased cardiac output

Question 18

What is the 1st line imaging for suspected heart failure?

1 - transthoracic echocardiogram (TEE)
2 - CT pulmonary angiogram (CTPA)
3 - MRI
4 - percutaneous coronary intervention

Answer 18

1 - transthoracic echocardiogram (TEE)

Able to assess:
- LV dimensions/function
- LV ejection fraction
- Estimate intra-cardiac pressures
- Investigate for valvular heart disease
- RV dimensions/Function
- Estimation of pulmonary hypertension

Question 19

Transthoracic echocardiogram (TEE) is the 1st line diagnosis for chronic heart failure, but what can we typically see on a chest X-ray?

1 - cardiomegaly
2 - pulmonary congestion
3 - kerley B lines
4 - bat wings sign (oedema)
5 - all of the above

Answer 19

5 - all of the above

Question 20

Do all patients with acute left ventricular failure (ALVF) require hospital admission?

Answer 20

• Typically yes

Patients with severe pulmonary oedema or cardiogenic shock may require admission to the high dependency unit or intensive care unit.

Question 21

Patients who present with acute left ventricular failure (ALVF) should be treated with which of the following approaches?

1 - Sit up
2 - Oxygen
3 - Diuretics
4 - Intravenous fluids should be stopped
5 - Underlying causes need to be identified and treated (e.g., myocardial infarction)
6 - Monitor fluid balance (urine output, U&Es etc)
7 - all of the above

Answer 21

7 - all of the above

Essentially spells out the mnemonic SODIUM

Sitting up helps patients breath as fluid not spread over such a large area.

ABG can guide oxygen therapy

Furosemide is the diuretic of choice to relieve fluid overload

Nitrates may be given alongside furosemide

Question 22

In severe cases of acute left ventricular failure (ALVF) all of the following may be used with specialist input:

• IV opiates = pain and act as vasodilators
• IV nitrates = act as vasodilators, may be suitable in severe hypertension IHD
• Inotropes (dobutamine) = improved cardiac output and contractility
• Vasopressors (noradrenalin) = improved BP by causing vasoconstriction
• Non‑invasive ventilation
• Invasive ventilation (involving intubation and sedation)

Question 23

B-blockers are used in chronic heart failure. When should this drug be stopped in acute heart failure?

1 - HR <50bpm
2 - 2nd degree Mobitz heart block
3 - 3rd degree Mobitz heart block
4 - cardiogenic shock
5 - all of the above

Answer 23

5 - all of the above

Question 24

In a patient with chronic heart failure that decompensates and becomes acute heart failure, should their medications such as ACI-I, B-blockers and potassium sparing medications be stopped?

Answer 24

• No

They need to be reviewed, but should not be stopped

Question 25

In a patient with an acute presentation of acute left sided heart failure due to an MI for example, the LV is dysfunction. This increases LA and pulmonary vein pressure, increasing pulmonary capillaries and causing pulmonary oedema. What must the pressure in the capillaires be at in order to cause pulmonary oedema?

1 - >25mmHg
2 - <100mmHg
3 - <5mmHg
4 - <10mmHg

Answer 25

1 - >25mmHg

• serum albumin is 25 g/L, so it must be higher than this
• causes increased hydrostatic pressure

Question 26

What is the most common cause of right sided heart failure?

1 - left sided heart failure
2 - IHD
3 - liver failure
4 - CKD

Answer 26

1 - left sided heart failure

• right sided heart failure is typically a chronic presentation

Question 27

In right sided heart failure in addition to oedema in the peripheries, fluid typically collects in all of the following EXCEPT?

1 - abdomen (ascites)
2 - pleural effusion
3 - elevated JVP
4 - cranial cavity

Answer 27

4 - cranial cavity

Question 28

n a patient with acute myocardial infarction there is an increase in pressure in LV which is transmitted backward into pulmonary capillaries causing oedema in the lungs. Which of the following are a sign of cardiogenic shock?

1 - thready and weak pulse
2 - BP = <90mmHg
3 - cold and clammy
4 - all of the above

Answer 28

4 - all of the above

• most common cause of cardiogenic shock is an MI

Question 29

If the RV fails, the pressure in the RA increases as it has to work harder to pump blood in the RV. Increased RA pressure can cause a raised JVP. Although this can cause a lot of things to happen, the 1st and most obvious sign this is occurring is what?

1 - cor pulmonale
2 - hepatomegaly
3 - splenomegaly
4 - peripheral oedema

Answer 29

4 - peripheral oedema

• can be sign of right sided heart failure