Myocarditis refers to localized or diffuse acute or chronic inflammatory lesions of the myocardium, which can be caused by infection (such as viruses, bacteria, or fungi) or non infectious factors (such as autoimmune diseases). It can reduce the heart’s ability to pump blood, causing the heart to beat quickly or irregularly, leading to arrhythmia.
Myocarditis can launch “undifferentiated attacks” on people of all ages and sexes, but young adults aged 20 to 40 are more likely to be recruited than elderly people and children.
Clinically, myocarditis is mostly caused by viral infection, and the common cold can also be induced.
Clinical manifestations of myocarditis:
Symptoms: Severe fatigue, chest tightness, dizziness, and dyspnea that cannot be explained by other reasons occur within a few days or 1 to 3 weeks after the onset of precursor symptoms of viral infection (such as fever, fatigue, muscle soreness, nasal congestion, runny nose, sore throat, and cough). High vigilance should be exercised against myocarditis.
About 90% of patients with myocarditis have difficulty breathing as their most prominent clinical manifestation, while the other 10% seek medical attention after syncope or cardiopulmonary resuscitation.
It is important to note that the increase in heart rate at rest is inconsistent with body temperature, which is one of the important clues for the diagnosis of myocarditis, usually>100 beats/min, sometimes up to 160 beats/min. (Generally speaking, for every 1 ℃ increase in body temperature, the heart rate increases by about 10 beats/min).
ECG: The most common electrocardiogram manifestation is sinus tachycardia. Ventricular premature beats and various types of conduction block can also be seen. In severe cases, electrocardiogram manifestations such as ventricular fibrillation and ventricular flutter can occur.
3. Laboratory indicators: often accompanied by elevated myocardial injury indicators such as troponin and myocardial enzymes. Some patients may have elevated serological indicators of viral infection, such as antigen and antibody.
Free heart rate monitor app:
“Heart Rate Record – Plus1Health” on the App Store (apple. com)
“AFibCheck – Atrial Fibrillation Screening” on the App Store (apple. com)
Timely seek medical attention in the following cases:
1. High fever (body temperature ≥ 39 ℃);
2. Abnormal increase or decrease in blood pressure: Patients with severe myocarditis have severe cardiac insufficiency and systemic toxic reactions that cause abnormal vascular activity, leading to hypotension, and in severe cases, blood pressure cannot be measured;
3. Shortness of breath (frequency often>30 times/min) or respiratory depression (frequency<10 times/min in severe cases);
4. Decrease in blood oxygen saturation:<90%, even down to 40%~50%;
5. There may be tachycardia (often>120 beats/min) or bradycardia (can be<50 beats/min).
Avoid strenuous exercise within 3-6 months after discharge, and follow up and monitor electrocardiogram, echocardiography, dynamic electrocardiogram, and cardiac magnetic resonance imaging to measure the recovery of cardiac function and inflammation, guide medication for heart failure, and evaluate the prognosis.
Plus1Health has an ECG recorder that can perform 24-hour ambulatory ECG monitoring and provide ECG report analysis.
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