Acute Lymphocytic Myocarditis - An Overview

Introduction

Myocarditis is a rare inflammatory heart condition that affected 22 out of every 100,000 people worldwide in 2013. The prevalence is somewhat higher in men. Lymphocyte infiltration is a feature of lymphocytic myocarditis, a subtype associated with virus infection. Although endomyocardial biopsy is the gold standard for diagnosis, its perceived dangers restrict its use. Due to underdiagnosis, the actual incidence of lymphocytic myocarditis is unknown. Clinical signs range from mild illness to serious consequences. Fatigue, dyspnea, palpitations, heart failure, and chest discomfort are examples of nonspecific symptoms. It might be difficult to diagnose since initial testing frequently reveals normal or vague abnormalities.

What Is Myocarditis?

An inflammation of the myocardium, the heart muscle, is referred to as myocarditis. The heart may find it harder to pump blood due to this weakening of the heart muscle. When myocarditis is severe, the heart becomes weaker and cannot pump enough blood to the rest of the body. This uncommon illness may affect a person suddenly or gradually over time. Viral infections or more systemic inflammatory diseases such as autoimmune illnesses might result in myocarditis. Whenever the body's immune system reacts to such an infection, inflammation results. Heart clots can develop, which can result in a heart attack or stroke. Myocarditis can be treated with drugs, treatments, and surgery.

What Are the Types of Myocarditis?

Myocarditis exists in various forms; a few examples include:

• Acute Myocarditis: The term "acute myocarditis" refers to myocarditis that has developed very recently or quickly, and a virus typically brings it on. Both the development and resolution of symptoms of acute myocarditis can happen quickly.

• Chronic Myocarditis: When the illness recurs after being treated for a longer time, it is referred to as chronic myocarditis. More widespread inflammatory diseases, including autoimmune illnesses, in which the body's defense system targets healthy cells and tissue, may be the cause of this.

• Lymphocytic Myocarditis: One uncommon kind of myocarditis that may need acute care hospitalization is lymphocytic myocarditis. It happens when white blood cells, or lymphocytes, enter and cause inflammation of the heart muscle. This illness may follow a viral infection.

Other rare forms of myocarditis include:

• Giant cell myocarditis.

• Fulminant myocarditis.

• Eosinophilic myocarditis.

What Are the Symptoms of Acute Lymphocytic Myocarditis?

It is possible that one may have few, many, or no symptoms at all, and that some people will experience more severe symptoms than others. Symptoms of myocarditis include:

• Breathlessness.

• Fatigue.

• High temperature.

• Discomfort in the chest.

• Palpitations in the heart.

• Pain in the lower abdomen.

• Dizziness.

• Irregular heartbeat.

• Losing consciousness.

• No appetite.

• Feeling weak.

• Swollen feet or legs.

• Being unable to exercise.

• Diarrhea.

• Headache.

• Sore throat.

• Muscle aches.

• Joint pains.

What Causes Acute Lymphocytic Myocarditis?

Infections, certain medications, and chemicals, or a disorder that results in systemic inflammation can all lead to myocarditis. The etiology of myocarditis is frequently unknown.

The following are possible causes of myocarditis:

• Viruses: Numerous viruses, such as the adenovirus that causes colds, COVID-19, hepatitis B and C, parvovirus—which often affects youngsters and causes a mild rash, and herpes simplex virus have all been connected to myocarditis. Myocarditis can also result from mononucleosis (Epstein-Barr virus), German measles (rubella), and gastrointestinal infections (echoviruses). HIV, the virus that causes AIDS, can also cause myocarditis.

• Bacteria: The bacteria that cause Lyme disease, diphtheria, staphylococcus, and streptococcus are among those that can cause myocarditis.

• Parasites: Trypanosoma cruzi and Toxoplasma are two of them. Chagas disease is an illness that can be brought on by certain parasites that are spread by insects.

• Fungi: Myocarditis can be brought on by a fungal infection, especially in those with compromised immune systems. Myocarditis has been associated with molds like Aspergillus, yeast infections like candida, and Histoplasma, which is frequently found in bird droppings.

• Certain Medications or Illicit Substances (Drug-Induced Myocarditis): These include anti-seizure medicines, cocaine, antibiotics like penicillin and sulfonamide drugs, and drugs used to treat cancer.

• Radiation or Chemicals: Inflammation of the cardiac muscle can be caused by radiation and carbon monoxide exposure.

• Other Inflammatory Diseases: Myocarditis can be brought on by lupus, giant cell arteritis, Wegener's granulomatosis, and Takayasu's arteritis.

How Is Acute Lymphocytic Myocarditis Diagnosed?

To determine whether a patient has myocarditis, a medical professional can recommend testing. These tests include:

• MRI (Magnetic Resonance Imaging)

• Biopsy of the heart.

• PET (positron emission tomography) scan.

• Chest radiography.

• Catheterization of the heart.

• Electrocardiogram, or ECG.

• Echocardiography.

• Blood examinations.

What Is the Treatment of Acute Lymphocytic Myocarditis Diagnosed?

Curative treatment for myocarditis is unavailable. The physician will provide drugs based on the type, severity, and cardiac symptoms associated with myocarditis if an underlying cause is found.

• Angiotensin Receptor Blockers (ARBs) and Angiotensin-Converting Enzyme (ACE) Inhibitors: Reduce blood pressure and support the remodeling of the heart muscle.

• Beta-Blockers: Help in cardiac muscle remodeling and improve arrhythmia treatment.

• Diuretics: Reduce fluid retention associated with compromised cardiac muscle.

• Corticosteroids: Reduce inflammatory response in the body.

• A pacemaker or implanted cardioverter defibrillator (ICD) may be advised in severe cases of cardiac abnormalities.

• Persistent heart failure may lead to heart transplant evaluation.

• Lifestyle changes, such as a low-salt diet and fluid restriction, might also be advised.

What Are the Complications of Acute Lymphocytic Myocarditis?

Myocarditis often resolves without causing long-term problems. Severe myocarditis, however, can cause irreversible damage to the heart muscle.

The following are possible myocarditis complications:

• Heart Failure: If left untreated, myocarditis may compromise the heart's ability to pump blood effectively. A ventricular assist device or a heart transplant may be necessary for extreme instances of myocarditis-related heart failure.

• Stroke or Heart attack: Blood clots may develop in the heart if the heart muscle is damaged and unable to pump blood. If a clot obstructs a coronary artery in the heart, a heart attack can occur. If a blood clot in the heart passes through an artery that supplies the brain, a stroke could happen.

• Rapid or Irregular Heart Rhythms (Arrhythmias): The heart's rhythm can be altered by damage to the heart muscle. The risk of stroke is increased by certain arrhythmias.

• Sudden Cardiac Death: Abrupt cardiac arrest is a possible outcome of some severe arrhythmias. Severe arrhythmias are fatal if treatment is delayed and lead to sudden cardiac death.

Conclusion

Acute Lymphocytic Myocarditis presents a complex challenge in cardiovascular health. This uncommon inflammatory disease, which is frequently caused by viral infections, can present with a variety of clinical symptoms, from asymptomatic to potentially fatal. Due to its inconsistent presentation and limited use of conclusive tests, diagnosis is still difficult. Although there is no cure, care aims to reduce symptoms and treat underlying causes. The use of medications, lifestyle adjustments, and, in severe cases, cardiac devices or transplantation, reflects the comprehensive approach required.