Causes of constrictive pericarditis is/are -

Primary pericarditis is uncommon . It most often is due to viral infections although bacteria, fungi, or parasite may also be involved . In most cases , pericarditis is secondary to acute MI , cardiac surgery, radiation to the mediastinum or processes involving other thoracic structure. Uremia is the most common systemic disorder associated with pericarditis. Less common secondary cause include rheumatic fever, SLE and metastatic malignancies Robbins 9 th edition page no. 403