Pericarditis Differential Diagnosis: Understanding Key Distinctions

Pericarditis, an inflammation of the pericardium, often presents with acute chest pain and must be carefully differentiated from other conditions that cause similar symptoms. Accurate diagnosis is essential to ensure appropriate treatment and prevent complications. Among the most critical conditions to distinguish are acute myocardial infarction and aortic dissection.

Acute Myocardial Infarction: Key Differences

One of the primary conditions to rule out when diagnosing pericarditis is acute myocardial infarction (AMI). While both conditions can present with chest pain and electrocardiogram (ECG) changes, there are notable differences. In AMI, ST-segment elevation typically appears with a convex upward pattern, and the ST-T wave evolution occurs rapidly—often within hours. The presence of cardiac biomarkers such as troponin or creatine kinase (CK-MB) is significantly elevated in myocardial infarction, showing a dynamic pattern inconsistent with pericarditis.

Furthermore, the affected ECG leads in AMI correspond directly to the location of the myocardial damage, and the affected area is usually more localized compared to the widespread involvement seen in pericarditis. These distinctions are crucial for guiding the correct clinical approach.

Aortic Dissection: Clinical Clues

Another life-threatening condition that may mimic pericarditis is aortic dissection. Patients with aortic dissection often have a history of hypertension and typically describe the pain as sudden, severe, and tearing in nature. The discomfort usually starts behind the sternum or in the back and may radiate to the extremities.

Diagnostic Tools for Aortic Dissection

When the dissection involves the pericardial space, it can lead to acute pericarditis-like ECG changes, making differentiation even more challenging. However, diagnostic imaging such as echocardiography often reveals a key finding: the presence of a mobile intimal flap within the aorta. This observation, along with the patient's clinical history, is instrumental in confirming the diagnosis of aortic dissection and ruling out pericarditis.