Rheumatic Fever & Heart Dxs Flashcards
Acute Rheumatic fever usually affects what age groups
Acute rheumatic fever usually affects children and young adults between the ages of 5 and 15 years.
Whats the pathophysiology of rheumatic heart dxs
Rheumatic fever is an autoimmune condition triggered by an immune-mediated response following an infection with specific strains of Group A Streptococcus bacteria. The pathogenesis involves several key steps:
- The initial trigger for rheumatic fever is an infection with Group A Streptococcus (GAS), particularly strains that are capable of producing certain antigens. These streptococcal bacteria are usually responsible for causing pharyngitis (strep throat).
- Some strains of Group A Streptococcus possess antigens that are structurally similar to certain proteins found in human tissues, particularly in the heart. The main antigens involved in this mimicry are M proteins of the streptococcus, which resemble cardiac myosin (a muscle protein in the heart) and sarcolemmal membrane proteins (membrane proteins of muscle cells).
- Because of this structural similarity, the immune system, when producing antibodies against the streptococcal antigens, inadvertently begins to target and attack the body’s own tissues, particularly those in the heart, joints, skin, and central nervous system.
- The antibodies produced against the streptococcal antigens cross-react with cardiac myosin and sarcolemmal membrane proteins, leading to an immune-mediated inflammatory response in the heart.
- This inflammation affects all layers of the heart: the endocardium (inner lining), myocardium (heart muscle), and pericardium (outer sac), resulting in pancarditis (inflammation of the entire heart).
In summary, rheumatic fever is a consequence of a delayed immune response to a Group A Streptococcus infection, where antibodies mistakenly attack the heart, joints, skin, and other tissues due to molecular mimicry. The resulting inflammation leads to damage in these tissues, particularly the heart, where Aschoff bodies are a distinctive feature. If left untreated or if the condition recurs, it can lead to chronic damage to the heart valves, known as rheumatic heart disease.
What are the hallmark of rheumatic carditis?
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- Aschoff nodules (or Aschoff bodies) are the hallmark of rheumatic carditis and are pathognomonic for rheumatic fever, meaning they are specifically associated with this condition and are not seen in other diseases.
- These nodules are composed of:
- Multinucleated giant cells: Large cells formed by the fusion of macrophages.
- Macrophages: A type of white blood cell that engulfs and digests cellular debris and pathogens.
- T lymphocytes: A type of immune cell involved in the immune response.
Aschoff nodules are typically seen where? And in what phase of the rheumatic carditis
- Aschoff nodules are typically seen in the heart muscle (myocardium) and develop as part of the inflammatory response. However, they are usually not present until the subacute or chronic phases of rheumatic carditis.
Rheumatic fever usually manifest __ to __ weeks after throat infection (pharyngitis) caused by Group A Streptococcus. However, in some cases, there may be no recollection or symptoms of the initial throat infection
2 to 3 weeks
What are the Common Clinical Features of Acute Rheumatic Fever
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General Symptoms:
- Fever: The most common presenting symptom.
- Anorexia and Lethargy: Patients may experience a loss of appetite and feel unusually tired.
- Joint Pain: Generalized body aches, especially joint pain, are common early symptoms.
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Arthritis:
- Frequency: Occurs in about 75% of patients.
- Characteristics: Typically presents as a migratory polyarthritis, which means that the pain and swelling move from one joint to another. The larger joints, such as the knees, ankles, elbows, and wrists, are most often affected.
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Carditis:
- Involvement: The heart may be involved in about 50% of cases, and this can affect the endocardium, myocardium, and pericardium.
- Symptoms: Patients might experience chest pain, shortness of breath, palpitations, and signs of heart failure. Rheumatic carditis can lead to chronic rheumatic heart disease if not properly managed.
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Skin Manifestations:
- Rashes: A specific type of rash known as erythema marginatum can appear. It is characterized by pink or red macules that spread outwards, leaving a central clearing. These rashes are often transient and non-itchy.
- Subcutaneous Nodules: These are small, painless lumps under the skin, usually found over bony prominences or tendons.
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Neurological Symptoms:
- Pancarditis: Inflammation affecting all layers of the heart, which can lead to severe complications.
The neurological symptoms on rheumatic fever is called?
- Chorea: Also known as Sydenham’s chorea, this is a neurological disorder characterized by rapid, involuntary, and irregular movements. It is more common in girls and typically occurs later in the disease course.
What’s the method for diagnosing Rheumatic fever?
The criterias
And some scenarios where you don’t use the method
The diagnosis of acute rheumatic fever relies on the revised Jones criteria, which include a combination of major and minor manifestations along with evidence of preceding streptococcal infection.
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Major Manifestations:
- Carditis
- Polyarthritis
- Chorea
- Erythema marginatum
- Subcutaneous nodules
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Minor Manifestations:
- Fever
- Arthralgia (joint pain without swelling)
- Elevated acute phase reactants (e.g., ESR, CRP)
- Prolonged PR interval on an ECG (suggesting heart block)
- Leukocytosis
- Typical Diagnosis: Requires either two major manifestations or one major and two minor manifestations, alongside evidence of a preceding streptococcal infection (such as a positive throat culture or elevated antistreptolysin O titers).
- Presumptive Diagnosis: In the absence of evidence of a preceding streptococcal infection, a presumptive diagnosis can be made in cases of isolated chorea or pancarditis after excluding other potential causes.
- Established Rheumatic Disease: In patients with a history of rheumatic heart disease or prior rheumatic fever, a diagnosis can be based on multiple minor criteria and evidence of preceding streptococcal infection.
Acute rheumatic fever can cause significant long-term morbidity, particularly through its effects on the heart, leading to rheumatic heart disease. Early recognition and treatment are essential to manage symptoms and prevent complications.
What are the clinical features of carditis caused by rheumatic fever
The severity and incidence of this inflammation vary with age, being more common in younger children and decreasing in frequency as patients grow older.
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Symptoms:
- Breathlessness: This can occur due to heart failure, which results from the weakened pumping function of the heart or from pericardial effusion (fluid accumulation around the heart).
- Palpitations: Patients might feel an abnormal or rapid heartbeat, often related to inflammation affecting the heart’s electrical system or to the heart struggling to compensate for valvular dysfunction.
- Chest Pain: This pain can arise from pericarditis (inflammation of the pericardium) or from generalized pancarditis. Pericarditis pain is often sharp and may worsen with deep breaths or lying down.
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Clinical Signs:
- Tachycardia: An increased heart rate that persists even when the patient is at rest. It may be one of the first signs of carditis.
- Cardiac Enlargement: The heart may become enlarged as it works harder to pump blood, especially if valves are damaged and blood flow is inefficient.
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New or Changed Heart Murmurs:
- Mitral Regurgitation: A common soft systolic murmur, which occurs when the mitral valve doesn’t close properly, allowing blood to flow backward into the left atrium during systole (the heart’s pumping phase).
- Carey Coombs Murmur: A soft mid-diastolic murmur caused by valvulitis (inflammation of the valve), typically affecting the mitral valve. The inflammation can cause nodules to form on the valve leaflets, affecting their function.
- Aortic Regurgitation: Occurs in about 50% of cases and is due to the aortic valve not closing properly, allowing blood to leak back into the left ventricle. This regurgitation leads to a distinctive diastolic murmur. The tricuspid and pulmonary valves are less frequently involved.
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Pericarditis:
- Chest Pain: Typically sharp and worsens with breathing or changes in position. It is a hallmark of pericardial inflammation.
- Pericardial Friction Rub: A characteristic sound heard with a stethoscope when inflamed pericardial layers rub against each other.
- Precordial Tenderness: Sensitivity or pain in the chest area over the heart.
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Heart Failure:
- Heart failure in this context can result from myocardial dysfunction (where the heart muscle itself is weakened) or valvular regurgitation (where faulty valves lead to inefficient blood flow and strain on the heart).
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ECG Changes:
- ST and T Wave Changes: These alterations can indicate myocardial involvement or inflammation in the heart. They are non-specific but suggest the presence of cardiac stress or injury.
- Conduction Defects: Such as AV block, where the electrical signals from the atria to the ventricles are delayed or blocked, leading to symptoms like syncope (fainting). AV block can range from mild delays in conduction to more severe forms that require urgent management.
Carditis in rheumatic fever is a serious complication that affects all layers of the heart, leading to various symptoms like breathlessness, palpitations, and chest pain. The condition can cause heart murmurs, heart failure, and changes in heart size and rhythm. Timely diagnosis and management are crucial to prevent long-term damage, such as chronic rheumatic heart disease.
Arthritis is the most common and often an early manifestation of rheumatic fever. It typically occurs when the levels of antibodies against the streptococcal bacteria are high in the blood. This form of arthritis has several distinctive features:
- Acute Onset: The inflammation of the joints comes on suddenly and can be quite severe.
- Painful and Asymmetric: The arthritis is usually very painful and affects different joints on opposite sides of the body.
- Migratory Nature: The inflammation tends to “migrate” from one large joint to another. For instance, it might start in the knee, then move to the ankle, elbow, or wrist.
- Large Joints Affected: The most commonly affected joints include the knees, ankles, elbows, and wrists. These joints often become red, swollen, and tender.
- Duration: The inflammation in each joint can last from a single day to about four weeks. The joints may seem to be involved one after the other in quick succession.
Two types of skin lesions are associated with rheumatic fever: erythema marginatum and subcutaneous nodules.
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Erythema Marginatum:
- Incidence: This skin condition occurs in less than 5% of patients with rheumatic fever.
- Appearance: The lesions start as red spots (macules) that fade in the center but remain red around the edges. This gives them a ring-like appearance, which can be described as “margins.”
- Location: These lesions primarily appear on the trunk and the proximal parts of the limbs (closer to the body), such as the upper arms and thighs. They usually do not appear on the face.
- Behavior: The red rings or margins can merge together (coalesce) or overlap with one another, creating a distinctive pattern on the skin.
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Subcutaneous Nodules:
- Incidence: These nodules occur in about 5-7% of patients with rheumatic fever.
- Characteristics: The nodules are small, firm, and painless, typically measuring between 0.5 to 2.0 cm in size.
- Location: They are usually found over bony surfaces or tendons, particularly on the extensor surfaces (the parts of the body where bones are closer to the skin, like the outer parts of the arms and legs).
- Timing: These nodules tend to appear more than three weeks after the onset of other symptoms, which means they are more useful for confirming a diagnosis of rheumatic fever rather than making an initial diagnosis.
In rheumatic fever, arthritis and skin lesions are key clinical features. The arthritis is migratory and affects large joints, while the skin lesions include erythema marginatum, a ring-like rash, and subcutaneous nodules, small firm bumps under the skin. These symptoms, along with other criteria, help in diagnosing and managing rheumatic fever.
Whats the hallmark of chorea?
Choreiform Movements: The hallmark of Sydenham’s chorea is the appearance of purposeless, involuntary movements, known as choreiform movements. These movements are often rapid, jerky, and non-rhythmic, typically affecting the hands, feet, or face.
What are the key features of chorea? And it’s clinical representation
Here are the key features:
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Onset and Timing:
- chorea generally appears at least 3 months after the acute episode of rheumatic fever.
- By the time it develops, the other signs and symptoms of rheumatic fever may have completely disappeared.
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Prevalence:
- This condition occurs in up to one-third of patients who have had rheumatic fever, with a higher incidence in females.
- it usually resolves on its own
- This condition occurs in up to one-third of patients who have had rheumatic fever, with a higher incidence in females.
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Clinical Presentation:
- Emotional Lability: The first noticeable sign of Sydenham’s chorea is often emotional instability. This might manifest as sudden mood swings, irritability, or inappropriate emotional responses.
- Choreiform Movements: The hallmark of Sydenham’s chorea is the appearance of purposeless, involuntary movements, known as choreiform movements. These movements are often rapid, jerky, and non-rhythmic, typically affecting the hands, feet, or face.
- Speech Changes: Patients may also experience changes in speech, which can become explosive and irregular, with sudden interruptions or halting.
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Course and Prognosis:
- Spontaneous Recovery: In most cases, the symptoms of Sydenham’s chorea gradually resolve on their own, with recovery typically occurring within a few months.
- Long-term Outcomes: However, about 25% of individuals who experience Sydenham’s chorea will later develop chronic rheumatic heart disease, particularly affecting the heart valves.
Sydenham’s chorea is a delayed, neurological complication of rheumatic fever characterized by involuntary movements, emotional instability, and speech changes, with a tendency to recover spontaneously. However, it carries the risk of leading to chronic rheumatic heart disease in a significant proportion of cases.
While less common, rheumatic fever can also affect other organs, leading to additional systemic manifestations:
- Pleurisy: Inflammation of the pleura, the membrane surrounding the lungs, causing sharp chest pain that worsens with breathing.
- Pleural Effusion: Accumulation of fluid in the pleural space, which can cause difficulty breathing and chest discomfort.
- Pneumonia: Inflammation of the lung tissue itself, though this is a rare complication in the context of rheumatic fever.
When arranging the signs and symptoms of rheumatic fever based on their time of onset, the presentation would look like this:
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Initial Symptoms (2–3 weeks after streptococcal infection):
- Fever: Typically accompanied by lethargy, anorexia, and general malaise.
- Joint Pain and Arthritis: Early onset, with acute, painful, asymmetric, and migratory inflammation of large joints like the knees, ankles, elbows, and wrists.
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Early Manifestations:
- Carditis: Symptoms like breathlessness due to heart failure or pericardial effusion, palpitations, chest pain from pericarditis, and new or altered heart murmurs. Other signs include tachycardia and potential cardiac enlargement.
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Skin Lesions:
- Erythema marginatum: Red macules that fade in the center but remain red at the edges, mainly appearing on the trunk and proximal extremities.
- Subcutaneous Nodules: Firm, painless nodules over extensor surfaces, appearing more than 3 weeks after the onset of other symptoms.
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Late Manifestation (At least 3 months after acute rheumatic fever):
- Sydenham’s Chorea (St. Vitus Dance): Characterized by emotional lability, followed by purposeless, involuntary movements of the hands, feet, or face, and potentially explosive, halting speech.
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Rare or Other Systemic Features:
- Pleurisy, Pleural Effusion, Pneumonia: These may occur but are less common.
This presentation order follows the typical progression of symptoms in rheumatic fever, from the initial signs that appear shortly after a streptococcal infection to the later and more chronic manifestations.
What are the investigations you will like to carry out in a patient suspended of rheumatic fever
When evaluating a patient suspected of having rheumatic fever, a series of investigations are typically performed to confirm the diagnosis, monitor the disease’s progress, and assess any complications, particularly cardiac involvement. Here’s a breakdown of the key investigations:
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Blood Tests:
- ** FBC:** To check for leukocytosis- ESR (Erythrocyte Sedimentation Rate) and CRP (C-Reactive Protein): These are nonspecific inflammatory markers that tend to be elevated in rheumatic fever. Monitoring these levels can help track the disease’s activity and response to treatment.
- Throat Culture: A throat swab is used to identify Group A Streptococcus, the bacteria responsible for the initial infection. However, because the streptococcal infection often resolves by the time rheumatic fever presents, throat cultures are only positive in about 10-25% of cases.
- Antistreptolysin O (ASO) Antibodies: This blood test detects antibodies produced against streptolysin O, a toxin produced by Group A Streptococcus. Raised ASO levels can provide supportive evidence of a recent streptococcal infection. However, it’s important to note that ASO levels might be normal in approximately 20% of adult cases of rheumatic fever and most cases of chorea.
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Echocardiography:
- Mitral Regurgitation: The most common echocardiographic finding in rheumatic fever is mitral regurgitation, often due to dilatation of the mitral annulus and prolapse of the anterior mitral leaflet.
- Aortic Regurgitation: This may also be present and can be detected via echocardiography.
- Pericardial Effusion: In some cases, fluid accumulation around the heart (pericardial effusion) can be seen.
Why would you like to do ESR and CRP test?
Both ESR (Erythrocyte Sedimentation Rate) and CRP (C-Reactive Protein) are essential tests in the context of rheumatic fever because they are markers of inflammation. Inflammatory processes in the body, such as those caused by an immune response to infection, result in elevated levels of these markers. Here’s why they’re particularly useful:
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Assessing Disease Activity:
- Rheumatic Fever: This disease is characterized by inflammation in various tissues, including the heart, joints, and skin. By measuring ESR and CRP levels, doctors can gauge the degree of inflammation present in the body. Elevated levels indicate active inflammation, which is typical during an acute episode of rheumatic fever.
- Monitoring Progress: As treatment for rheumatic fever progresses, ESR and CRP levels should decrease as the inflammation subsides. Monitoring these levels helps clinicians assess how well the patient is responding to treatment.
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Diagnostic Support:
- While ESR and CRP are nonspecific markers (meaning they can be elevated in many different conditions), their elevation in the context of other clinical signs and symptoms (e.g., joint pain, fever, and carditis) supports the diagnosis of rheumatic fever. They are part of the broader diagnostic workup, including clinical criteria like the Jones criteria, throat cultures, and serologic evidence of a recent streptococcal infection.
- What It Measures: ESR measures the rate at which red blood cells (erythrocytes) settle at the bottom of a test tube over a specified period, usually one hour. Inflammation causes certain proteins in the blood to become elevated, making red blood cells stick together and settle faster.
- Function in Diagnosis: A higher ESR indicates that the red blood cells are settling faster than normal, which is often due to increased levels of fibrinogen and other acute-phase proteins that are elevated during inflammation. Therefore, a high ESR can suggest the presence of an inflammatory condition like rheumatic fever.
- What It Measures: CRP is a protein produced by the liver in response to inflammation. The level of CRP in the blood increases rapidly within hours after the onset of inflammation or infection.
- Function in Diagnosis: CRP is more specific and sensitive than ESR and can provide an early indication of inflammation. In the context of rheumatic fever, a high CRP level reflects ongoing inflammation and helps monitor the effectiveness of treatment.
In summary, ESR and CRP are key tests in rheumatic fever to detect and monitor inflammation. Elevated levels of these markers provide supportive evidence of active disease and help guide treatment decisions. By tracking their levels over time, healthcare providers can assess the severity of the disease and the response to therapy.
How do you manage a rheumatic fever patient
The management of rheumatic fever focuses on preventing further cardiac damage and alleviating symptoms. Here’s an overview of the management strategy:
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Bed Rest:
- Purpose: Bed rest helps reduce joint pain and decreases the heart’s workload, particularly important in patients with carditis.
- Duration: The duration of bed rest is determined by the patient’s symptoms and inflammatory markers (e.g., ESR, temperature, and white blood cell count). Once these have normalized, the patient can gradually resume normal physical activities. However, strenuous exercise should be avoided, especially in patients who have experienced carditis.
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Medications and Other Treatments:
- Anti-inflammatory medications (e.g., aspirin or corticosteroids) may be prescribed to reduce inflammation and alleviate pain.
- Antibiotics are given to eradicate any residual streptococcal bacteria and prevent further infection.
- In cases with severe carditis, heart failure management may be necessary, including diuretics and other heart failure medications.
For rheumatic fever, investigations like ESR, CRP, throat cultures, ASO titers, and echocardiography are essential for diagnosis and monitoring. Management primarily involves bed rest to reduce cardiac workload, monitoring inflammatory markers, and using medications to treat symptoms and prevent further complications.
How do you Treat Cardiac Failure in Acute Rheumatic Fever
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Medical Management:
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Heart Failure: In patients with acute rheumatic fever who develop cardiac failure due to severe mitral or aortic regurgitation, initial treatment focuses on managing the heart failure symptoms. This typically includes:
- Diuretics: To reduce fluid overload.
- ACE Inhibitors or ARBs: To reduce afterload and improve cardiac function.
- Beta-blockers: To manage heart rate and reduce myocardial oxygen demand.
- Valve Replacement: If medical treatment is ineffective and the patient has severe valve dysfunction (especially in adolescents), surgical intervention may be necessary. Valve replacement can significantly improve cardiac function and reduce symptoms.
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Heart Failure: In patients with acute rheumatic fever who develop cardiac failure due to severe mitral or aortic regurgitation, initial treatment focuses on managing the heart failure symptoms. This typically includes:
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Atrioventricular (AV) Block:
- AV Block: This may occur in acute rheumatic fever but is generally not progressive and often resolves on its own. Rarely, if the block is persistent and symptomatic, a pacemaker might be required.
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Initial Treatment:
- Benzathine Benzylpenicillin: Administer a single intramuscular dose of 1.2 million units. This is effective in eliminating any residual streptococcal infection and is crucial to prevent further attacks of rheumatic fever.
- Oral Phenoxymethylpenicillin: An alternative to benzathine benzylpenicillin, taken as 250 mg four times daily for 10 days.
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Penicillin Allergy: For those allergic to penicillin, alternatives include:
- Erythromycin: An effective substitute.
- Cephalosporins: Another option for those with penicillin allergy.
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Long-Term Prophylaxis:
- Purpose: To prevent recurrence of rheumatic fever, particularly important if the patient has a history of streptococcal infections.
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Regimen:
- Oral Phenoxymethylpenicillin: 250 mg twice daily.
- Benzathine Benzylpenicillin: 1.2 million units intramuscularly every month if adherence to oral medication is a concern.
- For Penicillin-Allergic Patients: Sulfadiazine or erythromycin can be used, though sulfadiazine is less effective for eradicating group A streptococci but helps prevent infections.
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Duration:
- Typically, prophylaxis continues until the patient is 21 years old or 10 years after the last episode of rheumatic fever, whichever is later.
- For those with residual heart disease, it extends until 10 years after the last episode or until the patient reaches 40 years of age, whichever is later.
- In high-risk areas or occupations with high exposure, prophylaxis might be extended.
- Note: Long-term antibiotic prophylaxis prevents recurrent rheumatic fever but does not prevent infective endocarditis.
In managing acute rheumatic fever, treatment of cardiac failure focuses on symptom control and may require valve replacement if severe. Antibiotic therapy is crucial both initially to treat any remaining streptococcal infection and as long-term prophylaxis to prevent recurrence. Adherence to prophylactic regimens is vital, especially in high-risk situations or for patients with residual heart disease.
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Initial Treatment:
- Benzathine Benzylpenicillin: Administer a single intramuscular dose of 1.2 million units to eliminate any residual streptococcal infection.
- Oral Phenoxymethylpenicillin: Alternatively, 250 mg four times daily for 10 days can be used.
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Penicillin Allergy Alternatives:
- Erythromycin: Can be used if the patient is allergic to penicillin.
- Cephalosporins: Another alternative for penicillin-allergic patients.
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Long-Term Prophylaxis:
- Oral Phenoxymethylpenicillin: 250 mg twice daily.
- Benzathine Benzylpenicillin: 1.2 million units intramuscularly monthly if adherence to oral medication is a concern.
- For Penicillin-Allergic Patients: Sulfadiazine or erythromycin. Note that sulphonamides are not effective in eradicating group A streptococci but can prevent infection.
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Duration of Prophylaxis:
- Typically: Continue until the patient is 21 years old or for 10 years after the last episode of rheumatic fever, whichever is later.
- In High-Risk Situations: If an attack occurred in the last 5 years, or if the patient lives in an area with high prevalence or has a high-risk occupation, prophylaxis may need to be extended.
- With Residual Heart Disease: Prophylaxis should continue until 10 years after the last episode or until the patient reaches 40 years of age, whichever is later.
- Limitations: Long-term prophylaxis prevents further attacks of rheumatic fever but does not protect against infective endocarditis.
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Purpose:
- Relief of Arthritis Symptoms: Rapid relief of arthritis symptoms is typically observed with aspirin, and a response within 24 hours can help confirm the diagnosis of acute rheumatic fever.
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Dosage:
- Children: Start with 60 mg/kg body weight/day, divided into six doses.
- Adults: May require 100 mg/kg per day, up to a maximum of 8 g per day, depending on tolerance.
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Side Effects:
- Mild: Nausea, tinnitus, and deafness.
- Serious: Vomiting, tachypnea, and acidosis.
- Duration: Continue until the ESR (Erythrocyte Sedimentation Rate) has decreased and then gradually taper off.
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Purpose:
- Rapid Symptomatic Relief: Glucocorticoids provide more rapid relief of symptoms compared to aspirin, particularly in cases with carditis or severe arthritis.
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Dosage:
- Prednisolone: 1.0–2.0 mg/kg per day in divided doses.
- Duration: Continue until the ESR is normal, then taper off.
- Note: Long-term use of glucocorticoids has not shown additional benefit in rheumatic fever management.
The treatment of acute rheumatic fever involves antibiotics to eradicate residual streptococcal infection and prevent recurrence. Long-term prophylaxis with penicillin or alternatives is critical, especially in high-risk scenarios. Symptomatic relief for arthritis and carditis is achieved with aspirin and glucocorticoids. Monitoring and adjusting treatment based on patient response and laboratory markers like ESR is essential for effective management.
Over __ of patients with chronic rheumatic heart disease have mitral valve involvement
Over 90%
List the types of heart dxs caused by chronic rheumatic fever
Prevalence:
- Occurrence: Develops in about 50% of patients who have experienced rheumatic fever with carditis.
- Gender Distribution: More common in women, with approximately two-thirds of cases occurring in females.
- History: Some patients may not have a recognized history of rheumatic fever or chorea, making it challenging to trace back to an initial episode.
Valvular Involvement:
1. Mitral Valve:
- Most Commonly Affected: Over 90% of patients with chronic rheumatic heart disease have mitral valve involvement.
- Types of Damage:
- Mitral Stenosis: Accounts for about 25% of cases, where the valve narrows and impedes blood flow.
- Mixed Mitral Stenosis and Regurgitation: Found in approximately 40% of cases, involving both narrowing and leakage of the mitral valve.
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Aortic Valve:
- Second Most Commonly Affected: After the mitral valve, the aortic valve is the next most frequently involved.
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Tricuspid and Pulmonary Valves:
- Less Common: Involvement of the tricuspid and pulmonary valves is less frequent compared to the mitral and aortic valves.
Clinical Manifestations:
- Symptoms: Patients may experience symptoms related to the specific valves affected, such as dyspnea, palpitations, or signs of heart failure.
- Diagnosis: Typically involves echocardiography to assess valve structure and function, along with clinical history and examination findings.
Management:
- Treatment: Includes managing heart failure symptoms, possibly using medications such as diuretics, and, in severe cases, valve repair or replacement surgery.
Key Points:
- Chronic rheumatic heart disease can be a long-term sequela of rheumatic fever, affecting various heart valves with varying degrees of severity.
- Mitral valve involvement is most common, with both stenosis and regurgitation often observed.
- A thorough clinical assessment and imaging are crucial for diagnosis and management of the condition.
Whats the Pathogenesis of Chronic Rheumatic Heart Disease
Main Pathological Process:
- Progressive Fibrosis: This is the central pathological process in chronic rheumatic heart disease. The inflammatory response from rheumatic fever leads to fibrosis of the heart valves, pericardium, and myocardium.
Valvular Involvement:
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Mitral Valve:
- Fusion of Commissures: The edges of the mitral valve leaflets may fuse together.
- Shortening of Chordae Tendineae: The chordae tendineae, which anchor the valve leaflets to the heart muscle, may become shortened.
- Resulting in Mitral Stenosis: These changes lead to narrowing of the mitral valve, causing mitral stenosis, which may occur with or without associated regurgitation (backflow of blood).
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Aortic and Tricuspid Valves:
- Distortion and Rigidity: Similar fibrotic changes in these valves result in distortion and increased rigidity.
- Resulting in Stenosis and Regurgitation: These changes cause aortic and tricuspid stenosis (narrowing of the valve openings) and regurgitation.
Additional Contributions:
- Pericardium: Fibrosis may also involve the pericardium (the outer lining of the heart), contributing to pericarditis and related symptoms.
- Myocardium: The heart muscle itself can be affected by fibrosis, which may lead to heart failure and conduction disorders, further complicating the disease.
Pathological Cycle:
- Altered Hemodynamic Stresses: Once a valve is damaged, the altered blood flow (hemodynamic stresses) across the valve can perpetuate and extend the damage.
- Chronic Damage: This can continue even if the initial rheumatic process has resolved, leading to ongoing valve dysfunction and worsening symptoms.
Summary:
- Chronic rheumatic heart disease is characterized by progressive fibrosis affecting heart valves and other cardiac structures.
- The mitral valve is most commonly affected, leading to stenosis and/or regurgitation.
- Similar fibrotic changes in other valves can cause significant functional impairment.
- The damage perpetuates through altered blood flow dynamics, leading to long-term complications and disease progression.
Whats mitral stenosis
What are the consequences or complications of it
Mitral stenosis is a condition where the mitral valve in the heart becomes narrowed, restricting blood flow from the left atrium to the left ventricle. It is most commonly caused by rheumatic fever, though it can also result from severe calcification of the valve in older adults or be congenital.
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Rheumatic Origin:
- Fibrosis and Calcification: In rheumatic mitral stenosis, the valve leaflets undergo progressive fibrosis and calcification. This causes the valve to thicken and stiffen, reducing its opening.
- Fusion of Cusps: The edges of the mitral valve leaflets can fuse together, further narrowing the valve orifice.
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Normal vs. Stenotic Valve Area:
- Normal Mitral Valve: The mitral valve orifice is about 5 cm² during diastole (when the heart relaxes and fills with blood).
- Severe Mitral Stenosis: The valve orifice can become less than 1 cm² in severe cases. Symptoms typically become noticeable when the orifice is reduced to less than 2 cm².
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Impact on Heart Function:
- Decreased Filling: As the mitral valve narrows, the left ventricle receives less blood during diastole. Consequently, left atrial contraction becomes crucial for filling the left ventricle.
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Left Atrial Pressure: Increased difficulty in filling the left ventricle leads to increased pressure in the left atrium. This pressure can cause:
- Left Atrial Dilation: The left atrium enlarges due to the increased pressure.
- Pulmonary Congestion: Elevated left atrial pressure causes blood to back up into the pulmonary veins, leading to congestion and breathlessness.
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Effects of Increased Heart Rate and Cardiac Output:
- Shortened Diastole: Faster heart rates shorten the diastolic phase (when the mitral valve is open), causing a further increase in left atrial pressure.
- Increased Demands: Situations that require increased cardiac output, such as pregnancy or exercise, exacerbate the left atrial pressure and are poorly tolerated by the patient.
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Atrial Fibrillation (AF):
- Common Occurrence: Atrial fibrillation is a frequent complication due to the progressive enlargement of the left atrium.
- Impact on Symptoms: AF can lead to rapid heart rates and loss of coordinated atrial contraction, causing a sudden rise in left atrial pressure and pulmonary edema.
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Pulmonary Hypertension:
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Compensatory Mechanism: In some cases, elevated pressure in the pulmonary circulation helps prevent pulmonary edema. However, it also leads to:
- Right Ventricular Changes: Right ventricular hypertrophy and dilation.
- Tricuspid Regurgitation: The tricuspid valve may leak, leading to right heart failure.
- Patients’ Rhythm: Less than 20% of patients with mitral stenosis remain in sinus rhythm. Many who do have severe pulmonary hypertension and a small fibrotic left atrium.
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Compensatory Mechanism: In some cases, elevated pressure in the pulmonary circulation helps prevent pulmonary edema. However, it also leads to:
Mitral stenosis causes the mitral valve to narrow due to rheumatic fever-related fibrosis and calcification. This narrows the valve orifice, increasing left atrial pressure and causing symptoms like breathlessness. Increased heart rate and cardiac output needs can worsen these symptoms. Complications include atrial fibrillation and pulmonary hypertension, which further impact heart function and patient symptoms.
What are the Clinical Features of Mitral Stenosis
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Effort-Related Dyspnoea (Breathlessness):
- Cause: Due to reduced cardiac output and pulmonary congestion. Initially, breathlessness occurs with exertion but can progress to occurring at rest as the disease advances.
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Fatigue:
- Cause: Low cardiac output resulting from the impaired filling of the left ventricle.
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Hemoptysis (Coughing Up Blood):
- Cause: Pulmonary congestion and, in severe cases, pulmonary hypertension.
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Thromboembolism:
- Cause: Atrial fibrillation (AF) can lead to the formation of blood clots in the left atrium, which may dislodge and cause emboli. Before anticoagulant therapy, thromboembolism was a significant cause of death.
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Other Symptoms:
- Pulmonary Oedema: Fluid accumulation in the lungs due to left heart failure.
- Ascites and Oedema: Fluid retention and swelling in the abdomen and other parts of the body due to right heart failure.
- Palpitations: Often due to atrial fibrillation.
- Cough: Caused by pulmonary congestion.
- Chest Pain: Related to pulmonary hypertension.
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Atrial Fibrillation:
- Cause: Due to left atrial dilation and increased pressure.
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Mitral Facies/ Malar flush:
- Description: A characteristic flush seen in some patients due to low cardiac output.
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Auscultation Findings:
- Loud First Heart Sound (S1): Due to increased pressure forces closing the mitral valve.
- Opening Snap: Audible if the valve is not heavily calcified; moves closer to the second heart sound (S2) as stenosis worsens.
- Mid-Diastolic Murmur: Low-pitched, caused by turbulent blood flow through the narrowed valve. This murmur is accentuated by exercise and during atrial systole (pre-systolic accentuation).
- Pansystolic Murmur: If mitral regurgitation is present, it extends from the first heart sound and radiates towards the axilla.
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Additional Signs:
- Pulmonary Crepitations: Due to pulmonary oedema.
- Pleural Effusions: Fluid in the pleural space due to left heart failure.
- Right Ventricular Heave and Loud P2: Result from pulmonary hypertension, which can cause right ventricular hypertrophy and dilatation.
Mitral stenosis is characterized by a range of symptoms related to impaired blood flow through the heart and resulting complications, such as breathlessness, fatigue, and possible hemoptysis. Physical examination often reveals distinctive auscultatory findings, including a loud first heart sound, an opening snap, and a mid-diastolic murmur. These symptoms and signs reflect the progression and severity of the valve obstruction and associated complications like atrial fibrillation and pulmonary hypertension.