Myocarditis (Autoimmune)
Overview
Plain-Language Overview
Myocarditis (Autoimmune) is a condition where the body's immune system mistakenly attacks the heart muscle, causing inflammation. This affects the heart, which is responsible for pumping blood throughout the body. The inflammation can weaken the heart muscle, leading to symptoms like chest pain, shortness of breath, and fatigue. It may also cause irregular heartbeats or heart failure if severe. The condition can develop suddenly or gradually and may require medical evaluation to determine the cause and severity.
Clinical Definition
Myocarditis (Autoimmune) is characterized by inflammatory infiltration of the myocardium due to an aberrant immune response against cardiac antigens. It is a subtype of myocarditis where the immune system, often triggered by molecular mimicry or loss of self-tolerance, attacks the heart muscle without an infectious cause. This leads to myocyte necrosis, interstitial edema, and impaired cardiac function. Commonly associated with systemic autoimmune diseases such as systemic lupus erythematosus or giant cell myocarditis, it can cause arrhythmias, heart failure, and sudden cardiac death. Diagnosis requires exclusion of infectious etiologies and recognition of immune-mediated injury. The condition is clinically significant due to its potential to cause acute or chronic cardiac dysfunction.