Cardio 23 – Pathophysiology of Heart Failure
Anil Chopra
1. Definition of Heart Failure.
A complex syndrome that can result from structural or functional cardiac disorder that
impairs the ability of the heart to function as a pump, to support a physiological
circulation. The syndrome of heart failure is characterised by symptoms such as
breathlessness, fatigue and signs such as fluid retention.
Syndromes:
Acute Heart Failure- pulmonary oedema
Circulatory Collapse – cardiogenic “shock” (oliguria, hypotension)
Chronic Heart Failure – untreated, congestive, undulating, treated, compensated.
2. Epidemiology and Prognosis of heart failure
-
Prevalence 1-3%, Incidence 0.5-1% per annum
Becoming more common
Causes unpleasant symptoms
Identifiable (by national institute of Health and clinical excellence)
Poor prognosis – 50% dead in 3 years.
Treatable – expensive to NHS which uses 2% of its budget.
Peak age is 85 years
Same in men and women.
5% of acute hospital admissions 10% bed occupancy.
3. Aetiology of Heart Failure
Causes of heart failure include:
(1) Arrhythmias
(2) Valve disease
(3) Pericardial disease
(4) Congenital Heart disease
(5) Myocardial disease
Most common cause includes:
Coronary artery disease
Cardiomyopathy (dilated,
hypertrophic or restrictive) – this is
heart disease in the absence of a
known cause, particularly CHD,
valve disease or hypertension.
Hypertension.
Chain of events in coronary heart
disease
Risk
factors
Events and
syndromes
Causes of Dilated Cardiomyopathy





Idiopathic (cause unknown)
Genetic/familial
Metabolic disorders.
Autoimmune cardiomyopathies
Peri-partum cardiomyopathies.
Heart
failure
Atherosclerosis
Plaque growth
and instability
Myocardial damage
and remodelling
 Infectious disease ( HIV, bacteria, mycobacterium)
 Toxin/poison (Ethanol, metals, cocaine, hypoxia)
 Drugs (antivirals, chemotherapeutics)
4. Physiology of Heart Failure
Heart










Strength of heart beat reduced.
Remodelling (heart enlargement and hypertrophy)
Laplace’s Law
Starling’s Law – filling pressure raised
Heart become spherical rather than pair shaped
Peripheral Circulation
Neurohormonal response
Cytokine (inflammatory response)
Cachexia
Every Body organ is effected
Causes of Death
1) Progression of heart failure
a. Increased myocardial wall stress
b. Increased retention of sodium and water
2) Sudden Death
a. Opportunistic arrhythmia
b. Acute coronary event
3) Cardiac event e.g. myocardial
infarction
Progression of heart failure
4) Other cardiovascular even e.g.
Loss of myocardium
Bacterial invasion
stroke PVD.
Fall of BP - baroreceptors ergoreflexes
Immune & inflammatory response
& chemoreflexes activated
Maintains hormone activation
Onset of
heart
failure
5. Anatomy of Heart Failure
Cardiac monocytes are not able to be
replaced in such a way as to aid repair
of tissue.
 (tumours are rare, DNA turnover
not in normal myocardium or in
pathological states).
6. Pathophysiology of Heart Failure
See above diagram
7. Diagnosis of heart failure
Quality
of life
Onset of cachexia
Hastens demise
Progression
Sudden
death
Coronary
events
Mild
Moderate
Severe
Time
Death
Symptoms:
- Dysponoea
- Syncope
- Fatigue
- Palpitations
- Angina
Cardiovascular Events
- CHD
- Chest pain
- Coronary
bypass
- Thrombolysis
- Angioplasty
- Cardiac surgery
Other Risks
- Family history
- Smoking
- Diabetes
- Hyperlipidaemia
- Hypertension
8. Treatments for Heart Failure
(1) Prevention –
a. Prevent myocardial damage,
b. Prevent progression of the damage.
c. Prevent any other damage
(2) Relief –
a. Eliminating oedema and fluid retention
b. Increasing exercise capacity
c. Reduce fatigue and breathlessness
d. Lower left arterial pressure
(3) Prognosis –
a. Reduce mortality.
Ways of treating:
 Oxygen
 Intravenous diuretics
 Morphine
 Nitrates
 Vasodilators
 Surgery (inc. valve surgery)
 Implantable cardioverter, defibrillator
 Haemofiltration, peritoneal dialysis
 Aortic balloon pump
 Transplantation
Preventing
fun
cti
on
ala
ctivity.
ca
Ordin
ary
pa
physic Drugs and time in the treatment of CHD
alcit
activit
y y
physic
al
- Avoid alcohol
- Lower salt intake
- Lower Blood Pressure
- Increase Exercise
- Discourage smoking
- Change LDL/HDL ratio
- Immunisation form Flu
- Diet
9. Future Treatments
> Improved detection (screening)
> Wider use of drugs
> New Drugs
> Engineering (LV assist devices, synchronisation therapy)
> Biological solutions (cell regeneration, gene therapy, repair, transplant)
Lipid lowering
Hypotensive drugs
Aspirin
Asymptomatic
doesCHD
not
cause
undue
fatigu
e,
p
alpitat
ion,
dyspn
ea, or
angin
al
pain.
Aspirin
Thrombolytic agents
Heparin
Beta-blockers
ACE inhibitors
Acute myocardial
infarction
Lipid lowering
Aspirin
Beta-blocker
ACE inhibitor
Calcium antagonist
Nitrates
Anti-coagulant
Symptomatic
CHD
Diuretics
ACE inhibitors
Beta-blockers
? Digoxin
Others
Heart failure
Time