Acute pericarditis is an acute inflammatory disease of the visceral and parietal layers of the pericardium. The most common causes are viral infections and bacterial infections, but autoimmune diseases and uremia can also cause acute pericarditis. Characteristic pain behind the sternum or in the precordial area is common during the fibrinous exudative phase of the inflammation. This pain is associated with respiratory movements and often worsens with coughing, deep breathing, changes in body position, or swallowing. The nature of the pain is very sharp and can radiate to the neck, left shoulder, left arm, or even the upper abdomen. As the condition progresses, symptoms can shift from the fibrinous phase pain to dyspnea during the exudative phase. Some patients may develop significant pericardial effusion, leading to cardiac tamponade, and subsequently exhibit a range of related symptoms, including dyspnea and edema.