Radiation therapy is the second most common cause of constrictive pericarditis in the US (after viral/idiopathic)

• Constrictive pericarditis = Patient with history of chest radiation + right-sided heart failure + Pericardial knock (early diastolic sound that can mimic S3 resulting from loss of pericardial elasticity during ventricular filling) + Kussmaul’s sign
• Common causes of constrictive pericarditis include radiation therapy, cardiac surgery, connective tissue disorder, tuberculosis and viral pericarditis
• Jugular venous distention that increases with inspiration = Kussmaul’s sign = Constrictive pericarditis, right heart failure/infarction, restrictive cardiomyopathy
• Key idea: Patients with constrictive pericarditis or other forms of global diastolic dysfunction (restrictive cardiomyopathy) more commonly present with signs of right heart failure because the right heart is responsible for filling whereas the left heart is responsible for squeezing
• Cor pulmonale = Right-sided heart failure due to primary lung disease (COPD, ILD, etc.)