Introduction:
Myocardium is the muscular tissue of the heart that is responsible for the relaxation and contraction of the heart. It is responsible for pumping blood from the heart. The muscle tissue is made up of specialized cells called cardiomyocytes. The cardiomyocytes enable efficient pumping action. The myocardium receives the blood supply from the blood vessels of the heart. The blood vessels from the heart deliver oxygen to the heart's cells, allowing them to function properly. The myocardium is crucial for maintaining normal heart function. Normal heart function is influenced by many factors, such as lifestyle habits and other medical conditions. The cardiomyocytes are interlinked by intercalated discs that allow the synchronized contraction of the myocardium.
What Are the Functions of the Myocardium?
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Generates Force for Cardiac Contraction: The force generated by the myocardium for contraction is crucial for the adequate flow of blood to the tissues and organs. The myocardium pumps blood from the heart to the rest of the body through a contraction.
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Regulates Heart Rate: The myocardium also contains pacemaker cells that generate electrical impulses. These electrical impulses regulate the heart rate. The pacemaker cells coordinate with other cells to ensure proper rhythm of heart contractions.
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Provides Structural Support: The myocardium provides structural support to the heart and prevents the collapse of heart tissues under pressure. The other functions of the myocardium are regulation of blood flow through the heart’s blood vessels.
What Are the Causes of Myocarditis?
The causes of myocarditis are:
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Infectious Causes: The inflammation is caused by viruses such as adenovirus, Coxsackie virus, Epstein-Barr virus, and cytomegalovirus. Bacterial infections such as Chlamydia pneumonia, and streptococcal infections, fungal and parasitic infections also cause myocarditis.
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Non-Infectious Causes: The non-infectious causes include exposure to toxins, drugs, and autoimmune conditions. Alcohol, carbon monoxide, and cocaine can also cause symptoms of myocarditis.
The autoimmune causes of non-infectious diseases are scleroderma (a rare skin disease that involves tightening and hardening of the skin), rheumatoid arthritis (an autoimmune disorder that affects the joints), and lupus erythematosus (a chronic autoimmune disease that can affect the kidneys, skin, joints and blood vessels). Some antipsychotics, antibiotics, and chemotherapy are linked to myocarditis.
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Other Causes: In some cases, a history of autoimmune disorders and viral infections causes a weakened immune system.
What Is Parasitic Myocarditis?
Parasitic myocarditis is a rare condition that affects the heart tissues and the inflammation is caused by parasites. The most common parasites that cause myocarditis are Trypanosoma cruzi and Toxoplasma gondii. Other parasites that can cause myocarditis include Trichinella spiralis, Echinococcus granulosus, and Schistosoma mansoni.
What Is the Pathogenesis of Parasitic Myocarditis?
The pathogenesis of parasitic myocarditis involves several factors, such as host immune response, duration of infection, and the type of parasites involved.
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Parasites Involved: Several parasites, such as Trypanosoma cruzi, cause Chagas disease (an inflammatory and infectious condition caused by Trypanosoma cruzi). It is transmitted to humans through infected blood-sucking triatomine bugs. Toxoplasma gondii causes toxoplasmosis. These parasites infect the heart muscle leading to damage and inflammation.
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Host Immune Response: The immune response of the host plays a crucial role. The parasitic action triggers the immune response, which leads to inflammation. The immune response is too prolonged, leading to scarring and tissue damage. The host's immune system may fail to recognize the parasite, which leads to continuous inflammation and damage to the heart.
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Duration of Infection: Acute infections cause more inflammation and damage than chronic infections. Chronic infections lead to ongoing damage over time. Some parasites reactivate the infection after a period of latency. This leads to recurrent myocarditis episodes and ongoing heart muscle damage.
What Are the Symptoms of Parasitic Myocarditis?
The symptoms of parasitic myocarditis are:
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Fatigue: Due to reduced blood flow to the heart, the patient might experience tiredness and fatigue.
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Chest Pain: Chest pain is the most common symptom of parasitic myocarditis. The symptoms may worsen with physical activity, and the pain is sharp or dull.
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Shortness of Breath: Parasitic myocarditis causes difficulty in breathing during physical activity or when lying down.
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Nausea and Vomiting: Parasitic infections cause nausea and vomiting.
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Irregular Heartbeat: Parasitic infections cause abnormal heart rhythms, which lead to fainting and palpitations.
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Swelling: It causes swelling in the ankles, legs, and feet due to fluid collection.
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Fever: When the body fights against the infection, fever develops.
What Is the Diagnosis of Parasitic Myocarditis?
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To diagnose this condition, a series of tests are done to detect the signs of infection and inflammation. The tests include an electrocardiogram (ECG), echocardiogram, blood tests, magnetic resonance imaging (MRI), and computed tomography (CT) scans. A heart muscle biopsy is done to confirm the extent of the disease in the heart. A biopsy is a procedure in which a small tissue sample is removed from the person's body for examination under a microscope. The tissue sample for biopsy is obtained and examined for any abnormalities and to identify the extent of the disease.
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The treatment for parasitic myocarditis involves antiparasitic medications and supportive care to manage symptoms and prevent complications. The most commonly used antiparasitic medication is Benznidazole. It is given for 60 days.
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Another medication is Pyrimethamine-sulfadiazine. This combination medication treats infection caused by Toxoplasma gondii.
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Pyrimethamine-sulfadiazine works by inhibiting the folate synthesis in the parasite, thus killing the parasite. Another medication is Albendazole, which works by inhibiting the parasite's microtubule formation and inhibiting its ability to reproduce. The choice of antiparasitic medication depends on factors such as medical history, age of the patient, and health.
Conclusion:
Parasitic myocarditis is a rare condition in which parasites infect the heart tissue, leading to damage and inflammation. The treatment for parasitic myocarditis depends on the parasite type and the symptoms' severity. The most common parasite that can cause myocarditis is Trypanosoma cruzi. The treatment for parasitic infections typically involves antiparasitic medications such as Benznidazole. These medications are effective when given early, before any damage has been done to the heart.
