Myocarditis affects which part of the heart?

• A. Heart valves
• B. Heart muscle
• C. Pericardium
• D. Blood vessels

Answer: (B)

Myocarditis is inflammation of the heart muscle, the myocardium—the thick muscular layer that contracts to pump blood. When this muscle becomes inflamed, its ability to contract properly can be impaired, which may reduce the heart’s pumping function and disrupt electrical signals, potentially causing arrhythmias or heart failure in some cases. This is why the correct part is the heart muscle.

It’s not the heart valves, which are the flaps that open and close to regulate blood flow between chambers. It’s not the pericardium, the sac surrounding the heart. It’s not the blood vessels, which supply blood to the heart and to the rest of the body.