fulminant myocarditis



OVERVIEW

Definition

Myocarditis fulminans, also known as acute severe myocarditis, is the most serious type of acute myocarditis, characterized by severe onset, rapid progression, and high recent mortality, and occurs mostly in children and young adults.

The onset of fulminant myocarditis is acute, the condition develops rapidly, the condition progresses and deteriorates rapidly within 24 hours of the onset of the disease, and heart failure, arrhythmia and cardiogenic shock are the main manifestations [1-2].

Typing

According to the etiology of the disease

Infectious fulminant myocarditis is an inflammation of the myocardium caused by infection with various pathogenic microorganisms.

Non-infectious fulminant myocarditis refers to myocardial inflammation that can be caused by various non-infectious factors.

Morbidity

It can occur in people of any age and is more prevalent in the younger age group [3].

Etiology

Causes

Infectious

Infectious fulminant myocarditis is most commonly associated with viral infections. Previously, the most common pathogens of viral myocarditis were considered to be coxsackievirus and adenovirus, but in the last 10 years, the detection rate of fine virus B19 (PVB19) and human herpesvirus 6 (HHV 6) has increased greatly, and they are considered to be the most common pathogens. And PVB19 is the most predominant pathogen in pediatric fulminant myocarditis.

In addition to this it can also be associated with bacterial, fungal, helminthic, rickettsial, protozoal and other infections.

Non-infectious

Autoimmune diseases, e.g. systemic lupus erythematosus, vasculitis, tuberculosis.

Drug-induced, e.g. antibiotics, chemotherapy drugs, etc.

Toxicant-induced, e.g. carbon monoxide, etc.

Radiation-induced, e.g. radiotherapy

Predisposing factors

Overexertion, infectious diseases other than myocardial can increase the risk of fulminant myocarditis.

Pathogenesis

Infectious fulminant myocarditis is caused by pathogens and their toxins directly damaging myocardial cells or inducing an autoimmune response that leads to myocardial cell damage causing myocarditis.

Non-infectious fulminant myocarditis is caused by various other factors that directly or indirectly cause damage to myocardial cells, impairing the structure and function of cardiac tissue and causing myocarditis [4].

Symptoms

Prodromal symptoms

Mostly occurring 1 to 3 weeks before the onset of the disease, the symptoms are similar to those of a cold and can be easily overlooked. Common symptoms are as follows:

Fever.

Easy fatigue.

Muscle aches and pains.

Nausea.

Vomiting.

Acute phase symptoms

Palpitations (panic): may be manifested as a rapid heartbeat, a feeling of stopping, and a worsening of the heartbeat.

Chest pain, mostly manifested as left chest pain.

Chest tightness.

Dyspnea: may be manifested as breath-holding, shortness of breath; may be aggravated when lying down and alleviated when sitting or standing up.

Edema, mostly in the foot and calf. Pressing the edematous area may show depression.

Syncope, manifested as temporary loss of consciousness, which is of short duration [5].

Convulsions, manifested as generalized muscle stiffness and shaking, mostly accompanied by loss of consciousness.

Coma.

Respiratory cardiac arrest.

Sudden death, which occurs a short time after the onset of the disease.

Palpitations, chest pain, chest tightness, and dyspnea may worsen with activity and lessen with rest.

Consultation

Department of Medicine

Cardiovascular Medicine

Symptoms such as chest pain, palpitations, chest tightness, dyspnea, edema, etc. are recommended for prompt consultation at the Department of Cardiovascular Medicine.

Emergency Department

Sudden severe chest pain, dyspnea, etc., it is recommended to go to the Emergency Department immediately.

Preparation for medical treatment

Consultation: Registration, Preparation of documents, Frequently Asked Questions

Tips

Do not abuse medication without a doctor’s permission, so as to prevent the medication from affecting the relevant examinations and interfering with the diagnosis and treatment of the disease.

If you have persistent palpitations and panic attacks that cannot be relieved after catching a cold, please inform the doctor of your medical history.

Preparation Checklist

Pay special attention to the time of onset of symptoms, special manifestations, etc.

Did you have fever or muscle pain before the onset of the disease?

Are there any symptoms of palpitations, chest tightness, precordial pain at present?

How long have the symptoms lasted?

Are there any other signs of discomfort?

Is there any family history of related diseases?

Any drug or food allergies?

Any recent carbon monoxide poisoning?

Are there any other medical conditions? Any recent colds, gastroenteritis, hepatitis, etc.?

Test results in the last six months to bring to the doctor’s office

Blood test

Blood biochemistry

Cardiac enzymes

Myocardial Injury Markers

Pathology

Echocardiography

Cardiac Magnetic Resonance Imaging

Electrocardiogram and 24-hour ECG

Chest X-ray

Medication use in the last 3 months, bring box or package with you to the doctor if available

Glucocorticoids: dexamethasone, hydrocortisone

Diuretics: furosemide, hydrochlorothiazide

Cardiac stimulants: digoxin, digitalis

Antiarrhythmics: amiodarone, sotalol, dronedarone

Anti-infectives: penicillin, acyclovir

Anticoagulants: rivaroxaban, warfarin

Diagnosis

Diagnosis is based on

Medical history

History of infection with pathogens such as viruses and bacteria.

Autoimmune disease such as systemic lupus erythematosus.

History of medications such as antibiotics and chemotherapeutic drugs.

Carbon monoxide poisoning.

Radiation therapy.

Clinical manifestations

Fever, fatigue, nausea, vomiting.

Symptoms such as palpitations, chest pain, chest tightness, fainting, dyspnea.

Body temperature is normal or high.

Pulse may be in the normal range, or there may be arrhythmia or tachypnea.

Increased respiratory rate may be present in dyspnea.

Blood pressure may be normal or may appear to be below the lower limit of the normal range (less than 90/60 mmHg).

Heart borders may be normal or may appear enlarged.

The heart rhythm may be normal or there may be an irregular heartbeat rhythm. The sound of the heartbeat may be diminished in some areas, or there may be a gallop rhythm (a sound similar to a horse’s hooves hitting the ground as it runs).

Abnormal sounds may be heard in the lungs with breathing, similar to the sound of tiny water bubbles bursting.

Depressions may appear when pressure is applied to the lower extremities. The depression may recover slowly.

Laboratory Tests

Check white blood cell count, neutrophil count, and neutrophil percentage.

White blood cell count, neutrophil count, and neutrophil percentage may be elevated in bacterial infection.

Check the concentration of C-reactive protein.

It may be elevated.

Check the rate of erythrocyte sedimentation.

May be increased.

Check cardiac enzymes, creatine kinase isoenzyme (CK-MB), and troponin (TnT or TnI).

One or more of these may be elevated.

The main ones include B-type natriuretic peptide (BNP), N-terminal B-type natriuretic peptide proteins (NT-proBNP).

Check for cardiac function.

Elevated in severely impaired cardiac function.

Electrocardiogram

Determines cardiac function by examining the electrical signals of the heart. Low sensitivity for the diagnosis of myocarditis, characterized by sinus tachycardia and nonspecific ST-T changes.

ST-segment elevation or depression in a wide range of leads, T-wave inversion, poor R-wave augmentation, pathologic Q-wave and atrioventricular block, and intraventricular block suggest a poor prognosis.

Precautions

Imaging

Examine the chest.

Enlargement of the heart may be present.

Precautions: Remove jewelry or metal objects, such as necklaces, from the examination area before the examination, and clothing with metal materials should be removed.

Examination of the structure and function of the heart.

It may be normal or there may be abnormalities in the structure, systolic or/and diastolic function of the heart. In fulminant myocarditis, ultrasound tends to show diffuse myocardial hypokinesia, with or without pericardial effusion. Eruptive myocarditis is usually associated with severe myocardial systolic dysfunction and septal hypertrophy suggestive of tissue edema.

Precautions:

Myocarditis-specific changes, such as myocardial cellular and interstitial tissue edema, capillary exudation, congestion, and cellular necrosis and myocardial fibrosis, can be detected and can be a useful modality for differentiating myocardial infarction from myocarditis.

Endomyocardial biopsy (EMB)

Endomyocardial biopsy is the gold standard for the diagnosis of myocarditis, but has limited sensitivity and specificity. In a series of patients with suspected myocarditis, positive biopsy results were obtained in 38% of patients using Dallas histopathologic criteria. Endomyocardial biopsy provides pertinent information about the viral genome, fibrosis, cell death, type of inflammatory infiltrate, and iron, protein, or lipid deposition.

Myocarditis microscopically manifests as an interstitial inflammatory cell infiltrate with myocyte necrosis and/or myocyte degeneration, and myocardial samples obtained can be used for in situ hybridization with gene probes and in situ RT-PCR to clarify the etiology.

Virology

It is possible to determine the presence of a viral infection, as well as the type and severity of the infection. Endomyocardial biopsy is the gold standard for the diagnosis of myocarditis. The main manifestation is intermyocardial infiltration of inflammatory cells accompanied by myocardial necrosis.

In fulminant myocarditis, endomyocardial biopsy can identify giant cell myocarditis and eosinophilic myocarditis, the first two of which are more amenable to immunosuppressive therapy than lymphocytic myocarditis.

Diagnostic criteria

There are no clear diagnostic criteria for fulminant myocarditis, and national and international guidelines or consensus are mainly based on severe cardiac manifestations and the following investigations.

Blood biology: myocardial necrosis markers cTNI/T are significantly elevated; elevated CKMB and CK may be early clues.

Cardiac imaging: myocardial magnetic resonance imaging is valuable in the diagnosis of AMC, but only in patients with stable AFM; cardiac echocardiography is helpful in observing dynamic changes in cardiac structure and function, especially in the presence of hemodynamic deterioration, but it is not specific for diagnosis.

Myocardial histopathology: EMB is the gold standard for confirming the diagnosis of myocarditis. The underlying etiology and type of inflammatory cell infiltration suggested by myocardial immunohistochemistry and molecular biology tests (e.g., viral genes) are important for targeted treatment and prognosis of myocarditis.

Severe viral myocarditis can be diagnosed if a patient with myocarditis has one or more of the following manifestations: an episode of A. S. syndrome, congestive heart failure with or without myocardial infarction-like electrocardiographic changes, cardiogenic shock, acute renal failure, sustained ventricular tachycardia with hypotension, or myocardial pericarditis.

Differential Diagnosis

Coronary heart disease

Similarities: both have palpitations, chest pain, chest tightness, dyspnea, syncope.

Differences: Coronary heart disease is a disease in which the coronary arteries supplying blood to the heart are narrowed or blocked, resulting in ischemia of the heart muscle cells. It can be differentiated by coronary CTA and coronary angiography.

Mitral valve prolapse

Similarities: palpitations, chest pain, chest tightness, dyspnea, edema, syncope.

Differences: Mitral valve prolapse is caused by infection, which results in the development of redundant organisms in the mitral valve, and the mitral valve cannot be restored to its normal position, thus causing abnormal cardiac function. The early stage of mitral valve prolapse has no obvious lesions in the cardiomyocytes. It can be identified by echocardiography.

Hyperthyroidism

Similarities: palpitations, chest pain, chest tightness.

Differences: Hyperthyroidism is a disease caused by the overproduction of thyroxine, which can cause an increase in the metabolic level of the whole body, palpitations, irritability, hunger, fatigue, and weight loss. It can be identified by thyroid hormone test and thyroid ultrasound.

Broken Heart Syndrome (Stress Cardiomyopathy)

Similarities: Both have palpitations, chest pain, chest tightness and dyspnea.

Differences: Heartbreak syndrome is associated with abnormal mental state and abnormal behavior. There is mostly no obvious damage to the cardiomyocytes. It can be differentiated by ECG and other tests.

Treatment

Aim of treatment: Avoid further development of the disease.

Treatment principle: Early treatment to control the symptoms of fulminant myocarditis.

General treatment

Rest

Try to rest in bed.

Ensure adequate sleep and avoid late nights.

Avoid physical activity for at least 6 months during the acute phase, or as directed by your doctor.

Stabilize mood

Avoid emotions such as anger and anxiety, and avoid agitation.

Improve diet

Within 2~3 days of onset of the disease, low-salt and low-fat fluids should be chosen, with small and frequent meals; and the amount of fluid intake by mouth should be controlled and should not be more than 1,000 milliliters.

Food should be made into paste, so that it can be swallowed in the mouth, and enteral nutrition should be carried out under doctor’s guidance if necessary. The reference diet is: lotus root powder, rice soup, vegetable soup, oil-free broth, hot fruit juice, rice paste, egg custard, etc., and only light seasoning, should not put too much seasoning.

Avoid stimulating and bloating foods or drinks, such as coffee, strong tea, milk and soy milk.

Foods should not be too cold or too hot. Keep bowel movement smooth and do not exert excessive force to defecate.

Low salt, low fat and low cholesterol soft food should be the main focus, and food should be easy to chew and digest.

Except for frying, all other cooking methods can be used, but care should be taken not to put too much seasoning.

Celery, leeks, bean sprouts, bamboo shoots and other vegetables should not be eaten, and the rest of the vegetables should be chopped or stewed and eaten; meat should be used in soft, tender parts, such as fish (should choose less spiny or non-spiny), poultry.

You can follow the doctor’s advice to increase the intake of fruit and vegetable juices to supplement vitamins.

Avoid intake of whole grains such as beans and brown rice.

If insufficient nutrient intake occurs, enteral nutrition should be supplemented as prescribed by the doctor.

Monitoring Indicators

Monitor indicators such as blood pressure, heart rate, and heart rhythm.

Perform regular tests for markers of myocardial injury.

(ii) Drug therapy

Various drugs can be used to control fulminant myocarditis and improve myocarditis symptoms [6-7].

Control of heart failure

It can improve myocardial function and reduce cardiac load.

Commonly used drugs include diuretics (e.g., furosemide), vasodilators (e.g., sodium nitroprusside, isosorbide nitrate), and angiotensin-converting enzyme inhibitors (ACEIs, such as captopril).

Control of tachyarrhythmias

It can improve circulatory function and reduce the risk of malignant arrhythmias.

Commonly used drugs include amiodarone, sotalol, dronedarone, etc.

Anti-infection treatment

Can directly kill pathogens, or inhibit their proliferation.

Corresponding drugs are selected for the results of pathogenologic testing.

Commonly used drugs include antiviral drugs (e.g., acyclovir, ganciclovir, vasiclovir, ribavirin), antibacterial drugs (e.g., penicillin, metronidazole), and antifungal drugs.

Promote myocardial metabolism

It can improve myocardial metabolic function and protect myocardium.

Adenosine triphosphate, coenzyme A, inosine, cyclic adenosine monophosphate, vitamin C, coenzyme Q10 (pantethine), etc.

Improvement of immune function

It has some therapeutic effect on myocardial damage caused by immune injury.

Glucocorticoids, gammaglobulin, cyclophosphamide, azathioprine, etc. are commonly used.

Glucocorticoids can also be used in severe myocarditis, often for a short period of time.

Anticoagulation

Sustained heart failure is prone to embolic complications and anticoagulation may be considered.

Heparin, warfarin, and rivaroxaban may be used.

Mechanically assisted therapy

In critically ill patients with fulminant myocarditis, extracorporeal membrane pulmonary oxygenation (ECMO) can provide more powerful hemodynamic support.The principle of ECMO is to drain blood outside the body through the cardiopulmonary bypass pathway, and then return it back to the body after it is oxygenated by the membrane oxygenator.

Prompt use of intra-aortic balloon counterpulsation (IABP) is required in fulminant myocarditis combined with cardiogenic shock and insensitivity to antihypertensive drugs.IABP fills the ventricles during systole and contracts during diastole to reduce cardiac afterload, increase intracoronary blood flow, and increase cardiac output.

PVAD (percutaneous left ventricular assist device) increases cardiac output and decreases left ventricular afterload and is superior to IABP for hemodynamic support

Patients with myocarditis who present with symptomatic second-degree or greater atrioventricular block require implantation of a temporary pacemaker. Persistent AV block is less common.

Prognosis

Cure

The acute phase of fulminant myocarditis has a high morbidity and mortality rate, and the prognosis may be poor if it is not recognized or treated promptly.

The long-term prognosis of fulminant myocarditis is good if recognized early and accompanied by strong supportive and symptomatic treatment [8].

Hazards.

May cause cardiac disorders such as arrhythmias and dilated cardiomyopathy, which can affect quality of life.

It may cause cardiogenic shock, severe arrhythmia and life-threatening.

Sudden death may occur in severe cases.

Daily

Daily Management

Work and rest management

Avoid strenuous activities, keep a regular routine and avoid late nights.

In severe cases, bed rest is required.

Dietary management during recovery

Ensure adequate protein, vitamins, minerals and other nutrients, such as fish, tofu, skimmed or low-fat milk [9-10].

Ensure fresh fruits, fresh vegetables (especially dark green vegetables), nuts (not more than one palmful per day), etc.

Choose lean meat, or replace meat with beans and fish, and it is recommended to consume aquatic products twice a week (as prescribed by the doctor for those with combined gout or hyperuricemia).

Drink water as required by your doctor according to your health condition.

Avoid spicy and stimulating foods, such as raw onion, ginger, garlic, chili, mustard and curry.

Avoid stimulating beverages, such as alcohol, coffee, strong tea, etc.

Avoid high-sugar, high-salt and high-fat foods, such as sugary drinks, snacks, pickled foods, fried foods, barbecued foods, processed packaged foods, fatty meats, etc., and use no more than 6 grams of salt per day.

Abstain from alcohol.

Take dietary supplements as prescribed by your doctor and avoid taking them blindly.

Exercise management

Exercises such as brisk walking, playing tai chi, etc. can be performed, or suitable exercises can be selected according to the doctor’s advice.

Exercise should be gradual and avoid strenuous exercise or over-exercise.

Stop in time if you experience discomfort during exercise.

Emotion management

Avoid bad emotions such as tension, anxiety, anger and depression.

Emotions can be soothed by reading, listening to soft music, exercising moderately, and chatting with friends and relatives.

If the negative emotions are severe, psychotherapy may be conducted.

Habit management

Quit smoking and stay away from second-hand smoke.

Avoid infectious diseases

Avoid crowded places.

Wear a mask when you go out during the season of influenza and other infectious diseases.

Ventilate your room properly.

Pay attention to warmth and increase or decrease clothing appropriately.

Regular checkups

Follow your doctor’s instructions for regular checkups.

Monitor your blood pressure and pulse rate. Measurements can be made with a home blood pressure monitor.

Seek medical attention if you feel unwell

If you feel that your symptoms have worsened, or if new symptoms appear, you should consult your doctor.

Prevention

Balanced nutrition, low-salt and low-fat diet, can refer to the dietary advice for daily life.

Improve lifestyle habits, quit smoking and avoid inappropriate behaviors.

Exercise in moderation. It is recommended that adults should be active for more than 30 minutes a day, and children who are losing weight or are in the process of losing weight should be physically active for 60 minutes a day.

Avoid infectious diseases.

Actively treat other diseases, such as systemic lupus erythematosus.

Seek prompt medical attention for symptoms such as chest pain and chest tightness.