42 yo M is evaluated in the ED for an 8 hour hx of acute-onset chest pain. Pt characterizes pain as sharp and persistent. Lab studies reveal elevated CRP and leukocyte count elevated. There is a small pericardial effusion measuring 4 mm.What is the most likely diagnosis for the patient described?
a) Myocardial infarction
b) Acute pericarditis
c) Aortic dissection
d) Pulmonary embolism