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PATHOLOGY & PATHOPHYSIOLOGY
DISORDERS OF THE HEART
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© DOUGANS INTERNATIONAL. All rights reserved.
DISORDERS OF THE HEART
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Disorders of the Heart
Ischaemia
Angina pectoris
Myocardial
infarction
Inflammation &
infection
Pericarditis
Endocarditis
Myocarditis
Degenerative
disorders
Heart failure
Heart valve
disorders
Congenital disorders
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DISORDERS OF THE HEART
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Incidence:
Heart disease is the most common cause of morbidity and
mortality today!
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RISK FACTORS FOR CARDIOVASCULAR DISEASES
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Controllable:
That which we have control over, e.g. lifestyle, stress and
smoking
Uncontrollable:
That which we have no
control over, e.g. age,
gender, family history and
race
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RISK FACTORS FOR CARDIOVASCULAR DISEASES
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Smoking:
A smoker’s risk of developing coronary artery disease is directly related to
the number of cigarettes smoked per day
Smoking decreases HDL levels and increase LDL levels
Smoking increases the levels of carbon monoxide in the blood which may
directly injure artery walls and lead to atherosclerosis
Smoking leads to constriction of arteries, aggravating the lack of blood flow
in areas where the arteries are already narrowed by atherosclerosis
Smoking increases the blood’s tendency to clot, thus increasing the risk for
stroke, heart attack and peripheral vascular disease
People who quit smoking have only half the risk of those who continue,
regardless of the number of years smoked before
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ISCHAEMIC HEART DISEASE (IHD)
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
IHD = heart disease due to ischaemia (i.e. problems in the
coronary arteries)
Causes 20 to 30% of deaths in the western world
Usually due to atherosclerosis in the coronary arteries
Ischaemia = a deficiency in the blood supply to a part of the
body
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ISCHAEMIC HEART DISEASE (IHD)
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Consequences of IHD:
Angina pectoris
Myocardial infarction
Sudden cardiac death due to
arrythmias (irregular heart
rhythm)
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ANGINA PECTORIS
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Definition:
Episodic chest pain caused by ischaemia of the myocardium
Pain goes away after a few minutes of rest
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ANGINA PECTORIS
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Management of angina pectoris:
Avoid risk factors for atherosclerosis
Medicines: nitrates (dilate the arteries)
Surgery if severe: coronary angioplasty, coronary artery bypass
(“bypass surgery”)
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MYOCARDIAL INFARCTION (MI)
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Definition:
Necrosis of the myocardium as a result of severe ischaemia
Signs and symptoms:
Chest pain (same area as angina),
dyspnoea, nausea, vomiting,
syncope (fainting)
The pain is typically described as a
severe crushing or constricting
sensation in the chest
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MYOCARDIAL INFARCTION (MI)
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Complications of MI:
Sudden death
Arrythmia (irregular heart rhythm)
Thrombosis inside the heart
Pericarditis
Chronic left heart failure
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MYOCARDIAL INFARCTION (MI)
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Management of MI:
Oxygen
Analgesia (pain medication)
Nitrates (dilates arteries)
Fibrinolytic therapy (breaks down blood clots)
Anticoagulants (prevents blood clots)
B-antagonists (lowers the heart rate)
ACE inhibitors (lowers blood pressure)
Bed rest for 24 to 48 hours
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DISORDERS OF THE HEART
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Angina Pectoris Myocardial infarction
Pathogenesis:
Temporary blockage with
no tissue death,
especially after exercise
Complete blockage
resulting in tissue
necrosis
Signs & symptoms:
Symptoms last a few
minutes - pain, nausea,
sweating, dizziness and
shortness of breath
Symptoms last longer
than 30 minutes - severe
crushing pain
Alleviation of pain: Rest, nitro-glycerine Nothing
Treatment: Lifestyle changes Surgery plus lifestyle
changes
Complications: MI Death
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INFLAMMATION OF THE HEART
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Pericarditis Myocarditis Endocarditis
Aetiology: Viral, e.g. influenza,
HIV Viral Bacterial
Complications:
Scar tissue and
adhesions can form
that restrict the
heart movements
Heart failure and
sudden death
Heart failure,
damage to heart
valves, Rheumatic
fever
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INFECTIVE ENDOCARDITIS
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
The presence of valvular disease, prosthetic heart valves or
congenital heart defects provides an environment conducive to
bacterial growth on the endocardium
The bacteria form vegetations on damaged valves
Complications:
Damage to the valves, acute heart failure, emboli, infections in
other areas of the body
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RHEUMATIC FEVER
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Definition: An immune disorder that may occur 2 to 3 weeks after a
streptococcal throat infection
Aetiology: Autoimmune
Pathogenesis: Starts with a streptococcal throat infection (tonsillitis or
pharyngitis)
In some people the antibodies produced to fight the streptococcal
bacteria also attack body proteins (they cross-react). If this happens
you develop rheumatic fever. Your own antibodies then attack your
heart, joints, subcutaneous tissues and blood vessels.
Who is most at risk of getting rheumatic fever ?
School-aged children in developing countries
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STREPTOCOCCAL PHARYNGITIS (TONSILLITIS)
Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Signs and symptoms:
Sore throat, swollen tonsils
Throat is beefy red
Enlarged cervical lymph nodes
Fever
Headache
Nausea and vomiting
Rapid heartbeat
Malaise
In some children scarlet fever can develop: paleness around the mouth,
rest of face flushed. Red rash, redness in the skinfolds (rash is not itchy or
painful). Tongue white with red papillae (strawberry tongue).
Cough, laryngitis and a stuffy nose is not usually symptoms.
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Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Complications of rheumatic fever:
Heart valves can be damaged
Years after a bout of rheumatic fever, the patient can suffer from
heart disease due to the long-term effect of damaged valves on
the functioning of the heart
RHEUMATIC FEVER
Prevention of rheumatic fever:
When a child has tonsillitis or pharyngitis, the doctor should test
if it is a streptococcal infection. If it is, the child will require
antibiotics to prevent rheumatic fever
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Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Aetiology:
Congenital
Rheumatic fever
Endocarditis
Degeneration with ageing
HEART VALVE DISORDERS
Types of heart valve disorders:
Stenosis: This is abnormal rigidity of a valve
Regurgitation/incompetence: Failure of a valve to close fully
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Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Consequences of heart valve disorders:
HEART VALVE DISORDERS
If the valves are not working
properly, it means that the
heart has to work harder to
compensate
A serious valve disorder will
eventually lead to heart
failure
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Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
When the heart can not keep up with the demand of the body
Left sided heart failure or right sided heart failure or both
HEART/CARDIAC FAILURE
Aetiology:
Hypoxia, e.g. coronary artery disease, anaemia
Increased pressure: Left ventricle can fail if it has to pump against high
systemic blood pressure. Right ventricle can fail if it has to pump against
high pulmonary blood pressure.
Increased volume in the heart: aortic, tricuspid or mitral incompetence
Myocardial necrosis, e.g. MI
Deficient filling of the heart, e.g. mitral stenosis or pericarditis
Cardiomyopathy
Arrythmias
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Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Leads to increase pulmonary blood pressure and pulmonary
oedema
Signs and symptoms:
Dyspnoea on exertion
Orthopnoea
Paroxysmal nocturnal dyspnoea
Chronic cough
Tachycardia
Cyanosis
LEFT VENTRICULAR FAILURE
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Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Usually secondary to left cardiac failure
Signs and symptoms:
Ankle/sacral oedema
Increased JVP
Cyanosis
Enlarged and tender liver
Proteinuria
Nocturia
RIGHT CARDIAC FAILURE
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Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
Prevalence: Relatively common - 8 out of 1,000 live births
Aetiology:
Sporadic – no teratogenic factors can be identified
Maternal factors: Maternal rubella, maternal alcohol abuse,
intrauterine radiation, maternal use of certain medicines, e.g.
thalidomide
Genetic abnormalities ,e.g. Down’s syndrome
CONGENITAL HEART DISEASE
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Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
The most common congenital abnormality
Small or large defects
Management: Small defects often close spontaneously. Larger
defects will lead to cardiac failure, thus surgery is necessary.
VENTRICULAR SEPTAL DEFECTS
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Learner Study Guide – Pathology & Pathophysiology, Chapter 7, pages 55-62
VENTRICULAR SEPTAL DEFECTS
Source: www.dhg.org.uk,
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QUESTIONS