Myocarditis

Myocarditis or inflammatory cardiomyopathy is an inflammation of the heart muscle. Myocarditis can be caused by numerous toxic or infectious agents, including viruses, bacteria, fungal infections, or by autoimmune disease or a chest infection.

Coxsackievirus B3 has been found in 20-25% of patients with cardiomyopathy and myocarditis. In mouse models, Ampligen was found to be protective of Coxsackie B3-induced myocarditis.

More recently, myocarditis has been found in people who have recovered from COVID-19, including some people who were mildly ill or asymptomatic, including professional athletes. Myocarditis treatment varies from monitoring to anti-inflammatories, antibiotics and more intensive treatments. It is a significant cause of sudden cardiac death in professional athletes. Expert consensus advice has been published for competitive athletes who have tested positive for COVID-19.

Several studies of a mouse model of Coxsackie B3 myocarditis have found that exercise increases the virulence of the infection and results in poorer outcomes.

Signs and symptoms
Common myocarditis symptoms include:
 * shortness of breath, particularly during gentle exercise or walking
 * stabbing pain or tightness in the chest, which may spread across the body
 * flu-like symptoms including a high temperature, tiredness and fatigue
 * heart palpitations or an abnormal heart rhythm.

Many of these symptoms are also found in people with ME/CFS who do not have myocarditis.

Notable studies

 * Oct 26, 2020, Coronavirus Disease 2019 and the Athletic Heart. Emerging Perspectives on Pathology, Risks, and Return to Play - (Full text)

News articles, letters and blogs

 * Aug 2020, COVID-19 Can Wreck Your Heart, Even if You Haven’t Had Any Symptoms - Scientific American
 * Sep 11, 2020, A closer look at COVID-19 and heart complications among athletes - Genaro C. Armas, American Heart Association News
 * Sep 11, 2020, Cardiovascular Magnetic Resonance Findings in Competitive Athletes Recovering From COVID-19 Infection - Saurabh Rajpal, Matthew S. Tong, James Borchers, Karolina M. Zareba, Timothy P. Obarski, Orlando P. Simonetti, Curt J. Daniels. JAMA Cardiology.

Learn more

 * Myocarditis - British Heart Foundation