Administration of acetaminophen, colchicine, or narcotic analgesics may be reasonable if aspirin, even in higher doses, is not effective. (Level of Evidence: C) Class III: Harm 1. Glucocorticoids and nonsteroidal anti-inflammatory drugs are potentially harmful for treatment of peri- carditis after STEMI.510,511 (Level of Evidence: B) The incidence of acute pericarditis after STEMI has decreased with the aggressive use of reperfusion ther- Pericarditis should be considered in the differential diagnosis of recurrent chest pain after STEMI, particularly when the discomfort is pleuritic or posi- tional, radiates to the trapezius ridge, and is associated with a pericardial friction rub. Recurrent or worsening ST elevation without early T-wave inversion may be present. Distinction from reinfarction or acute stent thrombosis is crucial. In rare circumstances, if pain is persistent (>1 week) and accompa- nied by systemic features of malaise, fever, and increased inflammatory biomarkers, Dressler syndrome should be con- sidered. In most cases, the pain is self-limited and responds to conservative measures. The use of colchicine has been extrap- olated from its efficacy in other settings. Although pericarditis is not an absolute contraindication to anticoagulation,514 cau- tion should be exercised because of the potential for hemor- Asymptomatic pericardial effusions are common after It is important to exclude free-wall rupture when a pericardial effusion is present,518,519 especially if the O Gara et al 2013 ACCF/AHA STEMI Guideline e395 Whentamponadeispresent,free- wall rupture, hemorrhagic conversion, or aortic dissection should be considered.Anticoagulation should be discontinued in the pres- ence of a significant ( 1 cm) or enlarging pericardial effusion. 9.7. Thromboembolic and Bleeding Complications 9.7.1. Thromboembolic Complications 9.7.1.1. Anticoagulation: Recommendations Class I 1. Anticoagulant therapy with a vitamin K antagonist should be provided to patients with STEMI and AF with CHADS2 score# greater than or equal to 2, me- chanical heart valves, venous thromboembolism, or hypercoagulable disorder. 