Pfizer myocarditis and vaccines: what you need to know about the very rare side effect

Vaccines against COVID-19 they have saved millions of lives since they began to be applied in the world. Like all medicines, they have adverse effects.

In October, the General Directorate of Medicines, Supplies and Drugs (Digemid) of the Ministry of Health (Minsa) warned about the appearance of some possible cases of myocarditis and pericarditis after immunization against COVID-19 with vaccines that use the platform of Messenger RNA (mRNA), although these are known to be very rare.

According to Digemid Alert 062-2021, in Peru, the vaccine produced by Pfizer (Comirnaty®) uses the mRNA platform, and to date it has a conditional sanitary registry and is included in the Updated National Vaccination Plan against COVID-19.

This advisory document notes that in both cases, these reactions (myocarditis and pericarditis) occur when the body’s immune system is causing inflammation in response to an infection or some other trigger.

However, the Digemid clarified that it is necessary to emphasize that maintains the recommendation to continue vaccination with the Pfizer vaccine within the indications described in safety information, since, up to now, the balance risk benefit is still favorable. The cases are very rare.

What is myocarditis?

The myocarditis is inflammation of the heart muscle. It can affect the electrical system of the heart, reducing the heart’s ability to pump and can cause fast or abnormal heart rhythms (arrhythmias).

According to the mayoclinic.org portal, it usually occurs as a result of a viral infection, but it can be the result of a reaction to a drug or part of a more general inflammatory condition.

In severe myocarditis, the heart is weakened, so the rest of the body does not get enough blood. Clots can form in the heart that could lead to a stroke or heart attack.

Symptoms of myocarditis

If you have a moderate case of myocarditis or if you are going through the early stages, you may have mild or no symptoms, such as chest pain or shortness of breath.

In severe cases, the signs and symptoms of myocarditis vary depending on the cause of the disease. Common signs and symptoms of myocarditis are:

• Chest pain
• Abnormal or fast heart rhythms (arrhythmias)
• Difficulty breathing, at rest, or during physical activity
• Fluid retention with swelling of the legs, ankles, and feet
• Fatigue

What is pericarditis?

The pericarditis It is inflammation of the outer lining of the heart. It often causes sharp chest pain and sometimes other symptoms.

This reaction is usually mild and disappears without treatment, according to the mayoclinic.org web platform. Treatment of the most severe cases may include the administration of medications and, rarely, surgery.

Symptoms

• Chest pain is the most common symptom of pericarditis. It is usually sharp or stabbing. However, some people have a dull and persistent chest pain or that feels like pressure.
• The pain usually occurs behind the breastbone or on the left side of the chest.
• It can spread to the left shoulder and neck.
• It often intensifies when you cough, lie down, or take a deep breath.
• Sitting and leaning forward often relieve pain.

Other signs and symptoms of pericarditis may include the following:

• Abdominal or leg swelling
• Tos
• Fatigue or a general feeling of weakness or listlessness
• Low fever
• Pounding palpitations or a fast heartbeat (heart palpitations)
• Shortness of breath when lying down

What does the Digemid alert say?

The paper notes that these adverse events of myocarditis and pericarditis in the United States were detected particularly in teens and young adults, predominantly men over 16 years of age and can occur mainly after the second dose of the vaccine.

“The severity of myocarditis and pericarditis cases can vary. Most people who had the event after vaccination with an mRNA immunizing agent against COVID-19 in the United States and sought medical attention”, says the document.

Given this identification of adverse events, the Digems provided recommendations to health personnel and citizens. In that sense, he mentioned that it is necessary to identify the signs and symptoms related to myocarditis and pericarditis for subsequent notification to the Peruvian Pharmacovigilance and Technovigilance System, reporting it to the following email: [email protected].

Follow us on twitter: