Myocarditis is a rare inflammatory disease of cardiovascular disease that is primarily caused by sudden death, chest pain, heart failure, shortness of breath, fatigue, ankle swelling, edema. The cause is an inflammation of the heart muscle, most often following a viral infection, autoimmune disease. Most cases of myocarditis are identified in young adults with males affected more often than females because of smoking and industrial work. The diagnosis should be considered in any young adult with unexplained cardiac causes of shortness of breath, chest pain, faint, blurred vision, or loss of consciousness.
Symptoms
- The symptoms of myocarditis are not specific to the disease and are similar to symptoms of more common heart disorders that occur in a day.
- A sensation of tightness or squeezing in the chest that is primary symptom with rest and with exertion is common. Not infrequently chest pain is improved with leaning forward and worse with lying back when the inflammation affects the outer lining of the heart or pericardium and the heart muscle.
- If the heart pacing or conduction tissues become inflamed, a slow heart rate may cause fatigue or lightheadedness, faints. Inflammation can also cause extra beats that feel like a flutter in the chest.
- Sustained runs of extra beats or increases in quick succession may lead to lightheadedness or even loss of consciousness. Sudden death resulting from a myocarditis-related irregular heartbeat is an important cause of death in children and young athletes.
- In a majority of cases, the symptoms of myocarditis are found a few days to weeks by a flu-like illness, headache, restlessness. Specific viruses and even multiple virus infections may be seen in weak immune patients such as persons infected with HIV.
- Rarely myocarditis may caused by an adverse drug reaction. In this setting, the association between a new medication and myocarditis symptoms can suggest the cause.
Causes
Most cases of myocarditis are of unknown cause (idiopathic)and when the cause is identified, it is usually the result of an infection. In North America and Western Europe, Asia viral infections are the most common identified causes of myocarditis. In specific world regions, other important causes include myocarditis following a streptococcal bacterial infection, flu virus, unnest weather, and HIV-related infections. In specific Eurasian groups, bacteria such as diphtheria, rubella, and even scorpion bite have been identifying that cause myocarditis.
The heart injury may result directly from a toxic effect such as a toxin or a virus, and overuses of drugs, alcohol. More commonly myocarditis is a result of the body’s abnormal immune reaction to the initial heart damage. Most immune reactions are helpful and help to clear infections, but sometimes the scar tissue resulting from the inflammation can lead to a long-term decrease in heart function or chronic abnormalities in heart rhythm.
Sometimes the immune reaction fails to clear an infection which can lead to chronic viral myocarditis. Myocarditis can also accompany systemic inflammatory disorders such as lupus or Kawasaki disease.
Myocarditis is not inherited known genes associated with human myocarditis. When multiple family members are affected, the cause is usually due to common infection or bed environmental exposure. For example, experimental studies suggest that low blood levels of selenium and high levels of mercury in the air or around your household may worsen viral myocarditis.
Affected Populations
Myocarditis is most frequently diagnosed in younger adults between the ages of 20 and 40 years or over. Children seem to have a more severe presentation than adults with a greater proportion requiring temporary mechanical circulatory ventilations support. Men are generally more frequently affected than women, possibly due to the effects of testosterone on the immune reaction to infection. The relative frequency of more common age-related cardiovascular diseases such as coronary artery disease, heart disease may lead to underdiagnosis in the elderly. Certain forms of myocarditis, such as cardiac sarcoidosis, are the most common in black than white persons in the US. However, most forms of myocarditis have no known ethnic predisposition population.
The incidence and prevalence of myocarditis are not known widely available test that can be applied at a population level. The global burden of myocarditis has been estimated from population-based studies of heart muscle disease (heart disease not related to blocked arteries or abnormal heart valves).
Diagnosis
Myocarditis should be suspected in people who have recent onset cardiac symptoms, such as chest pains or trouble breathing, and who have no evidence of more common coronary artery disease, heart valve damage, or severe high blood pressure. In mild cases, characteristic features on cardiac magnetic resonance imaging (MRI) test strongly support the diagnosis and heart biopsy is not usually required.
In more severe cases or if patients fail to respond to standard medical care emergency conditions, a heart biopsy may be needed to confirm the diagnosis and guide therapy. There are no specific blood tests to confirm the diagnosis of myocarditis; however, an otherwise unexplained elevation in troponin may be found (a blood test that indicates heart muscle damage) and/or electrocardiographic features of cardiac injury are supportive.
Similarly new heart wall motion abnormalities or a fluid around the heart seen on echocardiography are not specific but support the diagnosis.
In mild cases of myocarditis, particularly with normal heart pump function test and evidence of inflammation of the adjacent pericardium, cardiac MRI is a reasonable confirmatory test. The diagnostic MRI features of acute myocarditis are often transient and evolve from a focal to a more diffuse pattern of injury injury.
In more severe cases of myocarditis, a heart biopsy should be performed when the information will uniquely impact prognosis or guide treatment. Heart biopsy should be done at centers with expertise in the technique so as to minimize the risk of procedure-related complications associate disease conditions. Centers performing heart biopsies should have access to cardiac pathological test to examine the heart tissue. In general, the diagnostic strategy to confirm myocarditis should balance probable clinical impact with safety.
Treatment
Myocarditis that presents with heart failure symptoms and decreased heart pump function should be treated according to the current national society guidelines for systolic heart failure. Drugs that block the immune system are generally not indicated for the management of the most common forms of myocarditis in adults specific forms of myocarditis such as giant cell myocarditis, cardiac sarcoidosis, or eosinophilic myocarditis, medications that modify the immune response should be considered. Sports participation during acute viral myocarditis may cause sudden death and treat with antiviral medicine. Thus high levels of physical activity following the diagnosis of myocarditis should be avoided for at least 3 to 6 months. Non-steroidal anti-inflammatory drugs such as ibuprofen should be avoided due to the risk of increased inflammation.
Some patients with severe myocarditis develop low blood pressure despite optimal medical care. These patients may require a temporary heart pump (a kind of mechanical circulatory support device) to survive the acute injury. Some of these patients with myocarditis can be bridged to recovery and have the pump removed. The survival after heart transplantation for adult patients with myocarditis is similar to that for other causes of cardiac failure. Patients with severe myocarditis should be seen by cardiologists with expertise in heart failure and heart rhythm disorder management.
