Pericardium

The pericardium is a saclike structure that envelopes the heart and origins of the great vessels. Pericardial effusions are categorized by characteristics of the accumulated fluid. Echocardiography is sensitive for diagnosis of pericardial effusion and can detect as little as 15 mL of fluid. Surgical options for management of pericardial effusions include subtotal pericardiectomy and pericardial window. Subtotal pericardiectomy can be performed via a right fifth thoracotomy in dogs. Pericardiectomy can be accomplished by videoassisted thoracoscopy using a transdiaphragmatic subxyphoid approach. Pericardial window can be performed through a mid-line celiotomy and transdiaphragmatic approach. Chronic inflammation of the pericardium results in extensive fibrous tissue proliferation and thickening of the pericardium. Constrictive pericarditis can be caused by any condition that results in chronic pericarditis. Definitive diagnosis of constrictive pericarditis is based on measurement of cardiac pressures. The effective treatment for constrictive pericarditis is pericardiectomy with or without epicardial decortication depending on the epicardial fibrous peel formation degree.