Systems Pathology: Heart Failure Flashcards Preview

Medicine 2 Week 6 - 11 > Systems Pathology: Heart Failure > Flashcards

Flashcards in Systems Pathology: Heart Failure Deck (22)
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1
Q

Heart failure

A

Condition caused by impairment of heart’s function as pump

2
Q

Clinical manifestations of heart failure

A
Fluid congestion (backward failure)
Inadequate blood flow to tissues (forward failure)
3
Q

Compare acute and chronic heart failure

A

In acute failure, events are rapid and consequence is forward failure (shock)

In chronic, compensatory mechanisms are brought into play and backward failure dominates (congestion)

4
Q

Compensatory mechanisms in chronic heart failure

A

Ventricular chamber enlargement - increases amount of blood in ventricle, so more is ejected at cost of fluid retetion

Muscle mass increase - Can eject more but more O2 required for larger muscle

Sympathetic stimulation - Increase in heart rate and contractility, redistribution and retention of fluid

5
Q

Cardiac remodelling that occurs in heart failure

A

Hypertrophy in response to greater demand

Adrenergic stimuli, cytokines & angiotensin II mediate effects

These increase cardiac output at cost of adverse effects

6
Q

Benefit/Harm from adrenergic signals to remodel heart after failure

A

Benefit

  • Contractility
  • Hypertrophy

Harm

  • Myocyte apoptosis
  • Myocyte toxicity
7
Q

Benefit/Harm from angiotensin II to remodel heart after failure

A

Benefit
- Hypertrophy

Harm
- Changed expression of contractile proteins

8
Q

Benefit/Harm from Cytokines (TNFa) to remodel heart after failure

A

Benefit
- Hypertrophy

Harm

  • Remodelling of matrix
  • Dilatation
9
Q

What does a dilating chamber indicate

A

A dilating chamber is a failing chamber

10
Q

Main 3 Types of heart failure

A

Left Ventricular Failure
Right Ventricular Failure
Congestive cardiac failure

11
Q

Consequences of LV failure

A

Raised end diastolic pressure –> raised LA pressure –> Raised pulmonary capillary pressure –>

Increased diffusion barrier for gas exchange & pulmonary oedema leading to breathlessness

12
Q

NY heart association - classification of heart failure

A

Class I No limitation of physical activity
Class II Slight limitation of activity (breathlessness/fatigue with moderate exercise)
Class III Marked limitation of activity (breathlessness with minimal exercise)
Class IV Severe limitation of activity (symptoms at rest)

13
Q

LVF on CXR

A
Alveolar oedema
kerly B Lines
Cardiomegaly
Dilated Upper lobe vessels
pleural Effusion

(ABCDE)

14
Q

Causes of LVF

A
Acute ventricular dysrythmias (VF)
MI/Ischaemic heart disease
Longstanding hypertension
Valve disease (Left side)
Cardiomyopathies & Drugs
Congenital heart disease
15
Q

Consequences of RV Failure

A

Raised end diastolic pressure –> raised RA & jugular venous pressures –> Raised central venous pressures –>

Hepatomegaly (abdominal discomfort) & pulmonary oedema

16
Q

Causes of RVF

A
Left Heart Disease
Lung disease
Thromboemboli
Haematopathologies
Pulmonary Arterial Hypertension (rare)
17
Q

RVF due to LV disease

A

Coronary artery disease causes myocyte damage; LV dilates & fails, increasing backward pressure in RA and pulmonary capillary bed
Pressure increases in pulmonary arteries to compensate leading to further damage to pulmonary arterial wall and greater resistance

18
Q

Emphysema causing RVF

A

Destruction of alveolar walls and loss of lung capillaries; failure of lung ventilation so hypoxia constricts pulmonary arteries and causes pulmonary hypertension and RVF

19
Q

Cor pulmonale

A

RVF as result of respiratory disease

20
Q

Congestive heart failure and causes

A

Combination of both LVF & RVF

Commonest cause of CCF is ischaemic heart disease followed by other causes of LVF
Also cardiomyopathies/drugs

21
Q

High Output Cardiac Failure

A

Heart muscle essentially normal but output cannot adequately perfuse tissue

22
Q

Consequences of High Output Cardiac Failure

A

Arteriovenous fistula - blood bypasses tissue
Septic shock
Anaemia
Thyrotoxicosis

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