Snapshot A 60-year-old woman presents with chest pain. She reports the chest pain started today and describes it as sharp and brief. When she sits up, the pain improves. She has no significant past medical history but endorses a viral respiratory infection a few days ago. On physical exam, she is in no acute distress. She has a low-grade fever. An electrocardiogram shows widespread ST segment elevation and PR depression in the precordial leads. Summary Pericarditis is a condition that results from inflammation of the pericardium characterized by sharp pain worsened by inhalation. It is most often idiopathic, but often due to viral illness, myocardial infarction, or radiation therapy. Patients present with pleuritic chest pain, usually relieved by sitting forward. Diagnosis is made when MI and pneumonia are ruled out with imaging and ECG, and PR depression is highly specific for pericarditis. X-rays can be normal in many patients, so other modalities like echocardiography and CT can help visualize inflammation and effusion in the pericardium. Treatment is usually pain relief, NSAIDs, and addressing the underlying cause. Operative treatment is indicated when there is an ineffective pharmacological response and in patients with chronic disease. Epidemiology Incidence common > 1/10,000 annual incidence viral pericarditis accounts for 70-90% of cases idiopathic pericarditis accounts for 10-30% of cases Demographics typically affects adults between the ages of 20-50 risk factors include previous myocardial infarction viral, bacterial, or fungal infection kidney failure or ESRD Etiology Pathophysiology mechanism inflammation of the pericardium triggers an immune response that results in swelling and fluid build-up in the pericardial space. infectious viral most common cause of pericarditis typically from Coxsackievirus bacterial Staphylococcus, Streptococcus, or M. tuberculosis fungal Toxoplasmosis non-infectious idiopathic autoimmune disease systemic lupus erythematosus rheumatoid arthritis uremia from acute or chronic renal failure rheumatic fever Associated conditions inflammation of the pericardium may cause a pericardial effusion pericardial effusion can worsen and develop into cardiac tamponade constrictive pericarditis typically a result of chronic pericarditis leading to a decrease in cardiac output common causes radiation therapy open heart surgery fibrinous pericarditis postinfarction fibrinous pericarditis is a complication of myocardial infarction within 1-3 days can develop weeks to months after an MI (Dressler syndrome) Anatomy Pericardium is the membrane that encloses the heart consists of two layers fibrous pericardium is the outer layer serous pericardium is the inner layer inner layer is further divided into two layers parietal pericardium visceral pericardium (epicardium) pericardial cavity is the space between the parietal and visceral pericardium normally filled with 15-50 mL of serous fluid Presentation History symptom onset within 4-6 weeks = acute symptoms persisting beyond 3 months = chronic Symptoms sharp pleuritic chest pain that is worsened by inhalation pain is also relieved by sitting up and leaning forward shoulder pain (referred pain) pericarditis is innervated by phrenic nerve Physical exam inspection some patients present with a low-grade fever hepatomegaly can be present in patients with chronic pericarditis auscultation findings friction rub high-pitched or scratching noise heard when auscultating the lower left sternal border pathognomonic for pericarditis, present in 85% of patients pulsus paradoxus provocative tests pleuritic chest pain test typically aggravated by coughing or deep inspiration and relieved by sitting up and forward Kussmaul sign (chronic pericarditis) ↑ jugular venous distention on inspiration pulsus paradoxus (chronic pericarditis) significant decrease in blood pressure during inspiration Imaging Radiographs recommended views chest x-ray with posteroanterior (PA) view findings heart often appears normal on radiography enlarged cardiac silhouette constrictive pericarditis may have pericardial calcifications on radiography Transthoracic Echocardiography indications to assess for pericardial effusion and cardiac tamponade views pericardial window is best seen on the subxiphoid view findings can be normal may have pericardial effusion Cardiac CT w/ IV contrast indications confirm diagnosis if initial findings on echocardiography are inadequate preoperative planning for pericardiectomy findings pericardial thickening and calcifications pericardial effusion Cardiac MRI indications used if the diagnosis is unclear with other imaging modalities preferred mode of imaging for the pericardium findings shows a thickened pericardium with pericardial effusion > 2mm = abnormal thickening Studies Serum labs ↑ erythrocyte sedimentation rate ↑ C-reactive protein may have ↑ troponin I troponin elevation is not predictive of negative outcome in pericarditis but does suggest some myocarditis is present ↑ creatinine kinsase Electrocardiogram (ECG) indications all suspected pericarditis patients should undergo ECG to rule out MI findings 4 typical stages in acute pericarditis Stage 1 widespread ST segment elevation PR segment depression, especially in lead II and in all leads except aVR ST depression in aVR and V1 Stage 2 ST segment normalization in ~1 week Stage 3 inverted T waves Stage 4 ECG findings return to baseline (typically weeks to months) classic ECG signs may be absent in uremic pericarditis Pericardiocentesis with fluid analysis indications patients with large effusion or tamponade suspected infection or exudative process (malignancy) findings positive gram stain or bacterial culture positive viral PCR acid-fast bacilli on smear microscopy and cell culture Differential Myocardial infarction (MI) findings found with myocardial infarction but not with pericarditis MI shows more focal ST elevation on ECG suggestive of anatomic damage Pneumonia (PNA) findings found with pneumonia but not with pericarditis patients with PNA will have suggestive chest x-ray findings like consolidation and air bronchograms while pericarditis is often normal on radiograph Cardiac tamponade findings found with cardiac tamponade but not with pericarditis patients with cardiac tamponade will present with Beck triad on exam Diagnosis Acute pericarditis requires 2/4 of the following criteria to be present to diagnose pericardial chest pain pericardial rub new widespread ST-elevation or PR depression on ECG new or worsening pericardial effusion Treatment Goals reduce inflammation and resolve underlying causes Medical pharmacological treatment NSAIDs indications first line treatment for post-MI pericarditis avoid other NSAIDs and use aspirin colchicine indications may be used in isolation or combination with treatments for acute pericarditis steroids and immunosuppressants indications for SLE for patients with contraindications to NSAIDs contraindicated immediately following MI to protect from ventricular wall rupture beta blockers indications for patients with perimyocarditis dialysis indications for uremia pericardiocentesis with pericardial fluid analysis indications required for large effusions and cardiac tamponade Surgical pericardiectomy indications reserved for constrictive pericarditis exhibiting symptoms of heart failure outcomes mortality rate of 6-12% Techniques Pericardiocentesis approach typically performed by interventional radiologists with local anesthesia and image guidance through fluoroscopy technique image-guided needle insertion into the pericardial space and removal of fluid complications bleeding infection arrhythmia reaccumulation of fluid Pericardiectomy approach typically done by cardiothoracic surgery under general anesthesia technique complete removal of the pericardium complications bleeding infection arrhythmia pericardial effusion Complications Pericardial effusion incidence up to 60-80% of cases treatment most cases are small-sized and often self-resolve for moderate to large-size effusion pericardiocentesis is used to remove excess fluid Cardiac tamponade incidence estimated to be less than 5% of cases risk factors development of pericardial effusion treatment fluid expansion with IV fluids urgent pericardiocentesis pericardial window placement Constrictive pericarditis incidence rare, ~ 1/100,000 annual incidence risk factors chronic or incessant pericarditis treatment same pharmacological agents as acute pericarditis pericardiectomy indications severe or recurrent pericarditis that is unresponsive to medical therapy Prognosis Overall favorable prognosis can be managed as an outpatient in most cases poor prognostic factors include high-grade fever lack of response to pharmacological therapy recurrent pericariditis pericardial effusion > 20mm on echocardiography Can recur or develop into chronic pericarditis