Myocarditis and Pericarditis

Pericarditis is an inflammation of the pericardium, often with fluid accumulation.  It can be caused by infection (often viral), myocardial infarction, drugs, malignancies, metabolic disorders, autoimmune disorders, or trauma.  Acute, subacute, and chronic forms exist.  Acute pericarditis is usually idiopathic and manifests as fever, pleuritic chest pain, and an audible pericardial rub by auscultation. Diffuse upwardly concave ST-segment elevations in the initial ECG and pericardial effusion on echocardiography confirm the diagnosis. Acute pericarditis is usually self-limiting (2–6 weeks); therefore, management is conservative. If cardiac tamponade or constrictive pericarditis develops, cardiac output can be severely reduced. Treatment depends on the cause, but general measures include analgesics, anti-inflammatory drugs, colchicine, and rarely surgery.

Myocarditis is an inflammatory disease of the myocardium, which may occur alone or in association with a systemic process. It can be acute or chronic, and the clinical presentation is highly variable. Myocarditis often presents with chest pain, dyspnea, or arrhythmias; the diagnosis should be suspected in patients without cardiovascular risk factors or cardiac symptoms after a recent viral upper respiratory infection. In the absence of cardiac symptoms, some patients have abnormal findings on ECG or cardiac biomarkers. There are numerous etiologies of myocarditis, but all lead to inflammation and myocyte injury, most often leading to signs and symptoms of heart failure. The course of myocarditis may vary based on the etiology and timeline of symptom progression. The diagnosis is supported by clinical findings, laboratory evaluation, and cardiac imaging. Cardiomegaly and contractile dysfunction are seen on echocardiography. A definitive diagnosis by endomyocardial biopsy is not always required. Management is supportive and aimed at addressing complications.

Pericardial effusion is the accumulation of excess fluid in the pericardial space around the heart. The pericardium does not easily expand; thus, rapid fluid accumulation leads to increased pressure around the heart. The increase in pressure restricts cardiac filling, resulting in decreased cardiac output and cardiac tamponade. Signs and symptoms usually occur in the setting of cardiac tamponade and include dyspnea, hypotension, muffled heart sounds, jugular venous distension, and pulsus paradoxus. The diagnosis of pericardial effusion is confirmed with echocardiography. Small effusions in stable patients are treated medically. Larger effusions and cardiac tamponade may require pericardiocentesis or pericardiotomy.

Myocarditis is an inflammatory disease of the myocardium, which may occur alone or in association with a systemic process. There are numerous etiologies of myocarditis, but all lead to inflammation and myocyte injury, most often leading to signs and symptoms of heart failure. The course of myocarditis may vary based on the etiology and timeline of symptom progression. The diagnosis is supported by clinical findings, laboratory evaluation, and cardiac imaging. A definitive diagnosis by endomyocardial biopsy is rarely required. Management is supportive and aimed at addressing complications.

Pericarditis is an inflammation of the pericardium, often with fluid accumulation.  It can be caused by infection (often viral), myocardial infarction, drugs, malignancies, metabolic disorders, autoimmune disorders, or trauma.  Acute, subacute, and chronic forms exist.  Acute pericarditis is usually idiopathic and manifests as fever, pleuritic chest pain, and an audible pericardial rub by auscultation. Diffuse upwardly concave ST-segment elevations in the initial ECG and pericardial effusion on echocardiography confirm the diagnosis. Acute pericarditis is usually self-limiting (2–6 weeks); therefore, management is conservative. If cardiac tamponade or constrictive pericarditis develops, cardiac output can be severely reduced. Treatment depends on the cause, but general measures include analgesics, anti-inflammatory drugs, colchicine, and rarely surgery.