**2. Pericarditis**

#### **2.1 Acute pericarditis**

Acute pericarditis can be diagnosed with at least two of the four following criteria: (1) pericarditic chest pain, (2) pericardial rubs, (3) new widespread ST elevation or PR depression on electrocardiogram, and (4) pericardial effusion (new or worsening). The additional supporting findings include (1) elevation of inflammation markers (C-reactive protein, erythrocyte sedimentation rate, and white blood cell count) and (2) evidence of pericardial inflammation shown by computed tomography or magnetic resonance imaging.

In developing countries, tuberculosis is the leading cause of pericarditis, and it is often associated with HIV infection. In developed countries, more than 80% of the cases are idiopathic, and the cause is often presumed as viral infection [2].

In terms of diagnosis of suspected acute pericarditis, electrocardiogram, transthoracic echocardiogram, chest X-ray, and assessment of inflammation markers and myocardial injury are recommended as a class I indication [1].

Predictors of poor prognosis for acute pericarditis include (1) fever >38°C, (2) subacute onset, (3) large pericardial effusion, (4) cardiac tamponade, and (5) lack of response to aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) after at least 1 week of therapy. If the patients are categorized in high risk (at least one risk factor of above), hospital admission is recommended. Outpatient management is recommended for low-risk patients.

Regarding treatment, aspirin or NSAIDs are recommended as first-line therapy with gastroprotection. Colchicine is also recommended as first-line therapy as an

adjunct to aspirin/NSAID therapy (**Table 1**). Evaluation of response to antiinflammatory therapy is recommended after 1 week. Low-dose corticosteroids can be considered in cases of contraindication/failure of aspirin/NSAIDs and colchicine, when an infectious cause is excluded or when there is a specific indication such as an autoimmune disease.
