Which of the following is a common cause of pericarditis?

• A. Acute myocardial infarction (MI).
• B. Hypertension.
• C. Atrial fibrillation.
• D. Aneurysm.

Answer: (A)

Pericarditis arises from inflammation of the pericardial sac, which is often triggered by processes that involve the heart muscle itself. When a myocardial infarction occurs, necrotic and inflammatory processes extend to the adjacent pericardium, leading to post-infarction pericarditis. This connection between myocardial injury and pericardial inflammation makes MI a classic and common cause. In some patients, especially weeks after an MI, an immune-mediated form called Dressler syndrome can develop, reinforcing the link between myocardial injury and pericarditis. Hypertension, atrial fibrillation, and aneurysm are not common causes of pericardial inflammation themselves; hypertension mainly affects pressures and remodeling, atrial fibrillation is an electrical disturbance, and an aneurysm, while dangerous, does not typically present as pericarditis.