Week 238 - Heart Failure

Question 1

Describe the key features of left-sided heart failure

Answer 1

Dyspnoea / Orthopnoea / PND (pulmonary congestion / oedema)
Frothy sputum
Signs of decreased tissue perfusion (decreased CO)
Signs of cyanosis or hypoxia
Exercise intolerance

Question 2

Describe features of right-sided heart failure

Answer 2

(Congestion of peripheral tissues)
Reduced liver function / hepatomegaly
Reduced GI function (anorexia, GI distress, weight loss)
Ascites / oedema
Raised JVP

Question 3

What is the overarching pathology with right-sided HF?

Answer 3

Systemic venous congestion

Question 4

Which organ commonly causes right-sided HF?

Answer 4

Lungs / lung diesease e.g. COPD and PE

Question 5

What is the term used when HF is a mixed picture of left and right-sided pathology?

Answer 5

Congestive Cardiac Failure

Question 6

List 3 common causes of left-sided heart failure

Answer 6

Ischaemia
Valvular disease
HTN

Question 7

What is paroxysmal nocturnal dyspnoea?

Answer 7

What someone awakens in the night feeling horribly short of breath the the point that they might need to stick their head out of a window to get fresh air in their lungs

Question 8

What are the key investigations to be done in the suspected heart failure?

Answer 8

Blood tests - renal function, anaemia, Trop T, thyroid function, brain natriuretic peptide (BNP)
CXR - if congested yes; in not no!
ECHO - stiff walls (diastolic), poor/weak contraction (systolic), regional wall abnormality (e.g. Post MI)

Question 9

Why might you also want to perform a profusion scan / angiogram?

Answer 9

To check coronary perfusion

Question 10

What two overarching pathophysiology types cause systolic heart failure? Is the ejection fraction preserved or reduced?

Answer 10

Increased afterload
Reduced contractility

Ejection fraction is reduced

Question 11

Give 3 causes of impaired contractility

Answer 11

Coronary artery disease (MI, transient myocardial ischaemia)
Chronic volume overload (aortic or mitral regurgitation)
Dilated cardiomyopathies

Question 12

Give 2 causes of increased afterload leading to systolic heart failure

Answer 12

Uncontrolled severe HTN

Advanced aortic stenosis

Question 13

What type of heart failure results in preserved ejection fraction?

Answer 13

Impaired Diastolic Filling

Question 14

List 5 causes of impaired diastolic filling

Answer 14

LV hypertrophy 
Cardiac fibrosis 
Restrictive cardiomyopathy
Pericardial tamponade or constriction
Transient myocardial ischaemia

Question 15

List the three compensatory mechanisms that occur in response to early stage heart failure

Answer 15

Frank-Starling mechanism
Hypertrophy and remodelling
Neurohumoral Activation

Question 16

How does the Frank-Starling compensatory mechanism work?

Answer 16

Acts to preserve forward cardiac output by increasing contractility and therefore stroke volume in response to incomplete ventricular emptying

Question 17

How does hypertrophy and remodelling compensate for heart failure?

Answer 17

Increased wall stress leads to myocardial hypertrophy and extra cellular matrix deposition. Helps to preserve cardiac output

Question 18

How does an eccentric and concentric hypertrophy pattern result?

Answer 18

Eccentric - response to volume overload (mitral/aortic regurgitation)
Radius enlargement in proportion to wall thickening

Concentric - response to pressure overload
Wall thickness increases without proportional chamber dilatation reducing wall stress substantially

Question 19

How does the neurohumoral activation mechanism initially compensate for heart failure?

Answer 19

• Sympathetic NS (adrenergic stimulation)
• ADH secretion
• RAAS stimulation
  (Enhances release of vasoconstricting / sodium-retaining neurohorones e.g. Ang. II, noradrenaline, endothelin1 and ADH (arginine vasopressin) - serve to increase TPR and improve systemic perfusion)

Question 20

What signs on CXR are typical of heart failure?

Answer 20

• bilateral perihilar shadowing “bat wing appearance” (pulm. oedema)
• cardiomegaly
• upper zone dilated pulmonary vessels (pulmonary venous HTN)
• Kerley B lines (septal lines - specific sign of pulmonary oedema)
• costophrenic blunting (pleural effusion)

Question 21

What does BNP stand for and when is it released?

Answer 21

BNP = Brain Natriuretic Peptide
It is released from the ventricles in response to excessive stretching of cardiomyocytes
N.B. Recombinant BNP (Nesiritide) is not used in Mx in UK pts

Question 22

What is meant by the term Orthopnoea?

Answer 22

Difficulty breathing when lying flat

Question 23

What is Paroxysmal Nocturnal Dyspnoea (PND)?

Answer 23

Waking at night gasping for breath - may feel need to stick head out of a window to get air into lungs

Question 24

What are the key investigations for suspected heart failure?

Answer 24

CXR
ECHO
Bloods

Question 25

What bloods should you request in a patient with suspected HF?

Answer 25

U&Es 
BNP (brain natriuretic peptide)
Trop T
Thyroid function 
Hb (Anaemia)

Question 26

What might an ECHO tell you?

Answer 26

Whether there is wall stiffening (diastolic failure)
Weakness in contractility (systolic)
Valvular dysfunction (systolic)
Regional wall abnormalities

Question 27

Why might a cardiac perfusion scan / scintigraphy be useful in the investigation of HF?

Answer 27

It illustrates the blood supply to the myocardium highlighting areas of ischaemia or infarction, may help decide whether or not a bypass or stent will be necessary or beneficial. Might give an idea of the type / cause of HF being dealt with and direct your management

Question 28

Match these pairs of phrases:
Calcium reuptake Systole

Diastole. Calcium release

Answer 28

Calcium RELEASE is associated with SYSTOLE

Calcium REUPTAKE is associated with DIASTOLE