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Flashcards in Heart Failure Deck (87)
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What is the definition of heart failure

An inability of the heart to generate a sufficient cardiac output to meet the demands of the body without an increased filling pressure
- this inability is secondary to an underlying cause


heart failure is a



syndrome means that in

- it is caused by something else - secondary to an underlying cause


How does the european society of cardiology define heart failure as

- symptoms consistent with heart failure
- objective evidence of cardiac dysfunction - systolic or diastolic
-if in doubt there is an improvement in symptoms with treatment


How many people have heart failure

- 900,000 heart failure suffers
- 65% caused by coronary artery disease and hypertension
- 1-2% of those under 70 and 10-20% of those over 70


why are women protected from heart failure

- female sex hormones
- other physiolgoical aspect


When do men and women tend to experience heart failure

= Women later than men as they are protected by sex hormones in comparison to men who experience its earlier


Describe what happens in acute heart failure

- Can be dramatic with flash pulmonary oedema - presents in extremis this requires a precipitant
- ischaemia
- arrhythmia
- intercurrent infection


Describe the gradual deterioration of acute heart failure

- Fluid accumulation
-falling exercise tolerance and fatigue
- orthopnoea and paroxysmal nocturnal dyspnoea


Name the other names for systolic heart failure

- Heart Failure with reduced Ejection Fraction (HFrEF) (usually less than 40%)
- Heart Failure with mildly reduced Ejection Fraction (HFmrEF)


Name the different levels of ejection fraction by echos

- mild = 46-55%
- moderate = 36-45%
- severe = less than 35%


if your ejection fraction is below 35% then your

risk of death month on month climbs more than if you have a higher ejection fraction


Name another name for diastolic heart failure

Heart Failure with preserved Ejection Fraction (HFpEF)


What happens in diastolic heart failure (Heart failure with preserved Ejection Fraction (HFpEF)

- increased stiffness in the ventricular wall and decreased left ventricular compliance leading to impairment of diastolic ventricular filling and decreased cardiac output


What does an echo look like in diastolic heart failure

- Left ventricular hypertrophy
- left atrial dilatation
- abnormal relaxation


what is maintained in diastolic heart failure

- Ejection fraction is maintained above 55%


What happens in left heart failure

- common clinical syndrome of Heart Failure with preserved Ejection Fraction (HFpEF) (diastolic heart failure)


What causes right heart failure

• left heart disease
• pulmonary hypertension (cor pulmonale)
• congenital heart disease and cardiomyopathy
- pulmonary stenos


What are the symptoms of right heart failure

- Peripheral oedema,
- nausea
- anorexia
- ascites
- facial engorgement
- epistaxis


what can the right heart not cope with

The right heart is a conduit to supply blood to the lungs and cannot cope with elevated pressures


What does a low output state mean

- patient has lots of fluid on board, peripherally shut down and capillary refill time is slow


What does a high output state mean

Heart is overworked
- physiological - pregnancy or athlete
- Pathophysiological - metabolic derangement - in those with thyrotoxosis or sickle cell disease

- failure occurs when the cardiac output fails to meet its needs
- there is initially features of RVF and later LVF


How does heart failure keep getting worse

Heart failure
- this causes decreased stroke volume and cardiac output
- this causes a neurohormonal response
- this leads activation of sympathetic system and renin angiotensin aldosterone system is activated
- this causes vasoconstriction, increased sympathetic tone, angiotensin II, endothelins, impaired nitric oxide release, sodium and fluid retention, increased vasopressin and aldosterone
- this causes further stress on the ventricular wall and dilatation leading to worsening of ventricular function
- this leads to further heart failure


Describe how the RAAS system works

- angiontensinogen is produced by the liver
- renin from the kidney acts on it and converts it to angiotensin I
- ACE in the lung then converts angiotensin I to angiotensin II
- angiotensin II causes vasoconstriction and enhanced sympathetic activity
- angiotensin II causes aldosterone release which causes sodium and water retention


describe the pathological process which happens when MI damage occurs

Myocardial damage
- causes activation of the sympathetic nervous system
- this can cause activation of the RAAS system leading to fluid retention and increased wall stress - this causes myocardial hypertrophy

- activation of the sympathetic system leads to vasoconstriction which causes increased wall stress which leads to increased myocardial oxygen demand and decreased contractility

- it also causes increased heart rate and contractility which leads to increased myocardial oxygen demand which leads to decreased contractility

- can cause direct cardiotoxicity which leads to myocyte damage


How do you would out cardiac output

cardiac output = heart rate x stroke volume


How is heart rate increased

via autonomic nervous system


describe how starlings law works

- as the preload increases this causes the heart to stretch
- this causes an increase in contractility
- at one point the heart has stretched too much and can no longer contract effectively


what does contractile function of the heart depend on

- velocity of muscle contraction
- amount of load being moved
- amount of stretch


What is the main cause of heart failure

• Ischaemic heart disease (35-40%)
• Dilated cardiomyopathy (30-35%)
• Hypetension (15-20%)