Andreeff, Renee A. MS, MPAS, PA-C
* Acute pericarditis is an inflammation of the pericardium, the fibroelastic sac that surrounds the heart. The pericardium comprises the visceral and parietal layers, which are separated by a potential space.
* Acute pericarditis is most commonly caused by viral infections (such as coxsackievirus and echovirus) or is idiopathic.
* Other causes of acute pericarditis include acute myocardial infarction (MI); uremia; systemic diseases such as lupus, thyroid disease, and mixed connective tissue disease; fungal infections, especially in patients with HIV; medications such as dantrolene, hydralazine, isoniazid, phenytoin, and rifampin; bacterial infections and tuberculosis; malignancies such as breast and lung cancer, leukemia, and lymphoma; radiation therapy of the lung or breast; invasive cardiac procedures; and chest trauma.
* Possible complications of acute pericarditis include pericardial effusion, cardiac tamponade, and myocardial involvement (myopericarditis and perimyocarditis).
* Patients will typically complain of sudden-onset pleuritic anterior chest pain that is sharp, exacerbated by coughing or inspiration, and is often relieved by sitting up and leaning forward. Pain may radiate to the back and trapezius ridge.
* Patients with viral causes may present with flu-like respiratory or gastrointestinal symptoms.
* Patients with causes other than viral may present with signs and symptoms of the underlying cause.
* Clinical presentation
* A pericardial friction rub on cardiovascular auscultation over the left sternal border is common and highly specific for acute pericarditis. The absence of a friction rub does not rule out pericarditis.
* Ewart sign (dullness and bronchial breathing between the tip of the left scapula and the vertebral column) may be present if the effusion is large enough to compress the base of the left lung.
* Patients may be febrile, especially when the cause of pericarditis is infectious.
* Patients with chest pain must always be evaluated to rule out life-threatening causes of chest pain such as MI, pulmonary embolism, and aortic dissection.
* In cardiac tamponade, signs and symptoms can include restlessness; sharp stabbing chest pain that radiates to the neck, shoulder, back, or abdomen; dyspnea; light-headedness; pulsus paradoxicus; tachycardia; tachypnea; narrow pulse pressure; and diminished heart sounds on cardiac auscultation. ECG changes include reduction in amplitude of the QRS complexes and electrical alternans of the P, QRS, and T waves.
* The diagnosis is usually made based on history of pleuritic chest pain and confirmed with auscultation of a pericardial friction rub.
* An ECG typically will show widespread upward concave ST-segment elevation and PR-segment depression in the limb leads. T-wave depressions may be seen several days later, after ST segments return to normal.
* A chest radiograph is typically normal in acute pericarditis. However, the diagnosis should be suspected if a patient's chest radiograph reveals cardiomegaly of new onset.
* Laboratory studies should include complete blood cell count, troponin level, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP). Laboratory signs of inflammation (elevated white blood cell count, elevated CRP, and ESR) may be present, but are nonspecific. Troponin I elevation is due to epicardial cell damage.
* Electrolytes, blood urea nitrogen, and creatinine should be drawn to evaluate for potential presence of uremia.
* Blood cultures should be drawn if the patient presents with a fever of 100.4° F (38° C).
* If tuberculosis is suspected, send a sputum sample for acid-fast bacilli and a polymerase chain reaction assay.
* Echocardiography may be normal but is the most simple diagnostic tool to use to determine if pericardial effusion is present. Absence of an effusion does not exclude the diagnosis. Urgent echocardiography is required if cardiac tamponade is suspected.
* CT or MRI can be used to confirm the presence of pericardial fluid, measure pericardial thickness, and visualize neoplastic causes.
* The most sensitive method for the diagnosis of acute pericarditis is delayed enhancement of the pericardium on cardiac MRI.
* Treatment of acute pericarditis should be tailored to the underlying cause.
* Most cases can be managed in an outpatient setting with medical therapy alone with the goal of reducing pain and resolving the inflammation.
* Medical therapy includes oral administration of nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (600 to 800 mg every 6 to 8 hours for 1 to 2 weeks, followed by gradual tapering of the dose by 800 mg per week for 3 additional weeks).
* Indomethacin (50 mg three times a day for 1 to 2 weeks followed by a slow tapering) also has shown efficacy in treating acute pericarditis.
* Colchicine (0.6 mg twice daily for 3 months, with or without NSAIDs) may be considered in all patients with acute pericarditis, especially those who have not responded to NSAID therapy alone after 7 days.
* Refractory cases and patients with pericarditis due to connective tissue disease and failure of or contraindications for NSAID use can be treated with prednisone 0.25 to 0.5 mg/kg/day for 2 weeks (slow tapering) plus colchicine (0.5 mg to 0.6 mg twice daily for 6 months).
* Corticosteroid use increases the risk for recurrent pericarditis.
* A proton pump inhibitor should be prescribed with NSAID therapy for gastric protection.
* NSAIDs (other than aspirin) and glucocorticoids should not be used in patients with post-MI pericarditis.
* Avoid indomethacin in patients with coronary artery disease because it decreases coronary blood flow.
* Patients should avoid physical activity until symptom resolution. In cases of myocardial involvement, physical activity should be avoided for 6 months or until all laboratory studies return to normal.
* Patients at high risk for complications should be hospitalized. High-risk symptoms and signs include fever over 100.4° F, cardiac tamponade, large pericardial effusions, immunosuppressed state, acute trauma, elevated cardiac troponin, history of oral anticoagulant therapy, and patients who fail to respond to NSAID therapy within 7 days.
* Invasive procedures such as pericardiocentesis and pericardial biopsy may be required for patients who have a large pericardial effusion causing cardiac tamponade, suspicion of a neoplastic or bacterial cause, or evidence of constrictive pericarditis.
* Prognosis for acute pericarditis of idiopathic and viral origin is good, although following the initial episode of acute pericarditis, 24% of patients will experience a recurrence within the first few weeks.
© 2014 American Academy of Physician Assistants.