Pericarditis is secondary to inflammation of the pericardium and is characterized by chest pain and dyspnea. Acute pericarditis is the most common pathologic process affecting the pericardium. The chest pain is pleuritic, often relieved by sitting forward, and not related to exertion. Trapezius ridge (muscular angle between shoulder and neck) pain is pathognomonic for pericarditis.
The physical exam is characterized by the presence of a pericardial rub. Associated ECG changes include down-sloping of the PR interval and J point elevations diffusely except in leads aVR and possibly V1. Over the next few days after presentation, the J point returns to baseline followed by T wave inversion. This is opposite of what is seen with ischemic J point elevation in which inversion of the T waves occurs before the J point returns to baseline. The T wave abnormalities will revert to normal over the next few weeks to months. Echocardiography is also helpful in establishing the diagnosis. A lack of wall motion abnormalities helps eliminate myocardial infarction. Also, echocardiography can identify the presence of a pericardial effusion.
Pericarditis can be the result of underlying infection, malignancy, uremia, myxedema, medication side effects, connective tissue diseases, or trauma. It can occur after a myocardial infarction (Dressler syndrome) or cardiac surgery (postcardiac injury syndrome or postpericardiotomy syndrome). Many cases are idiopathic with no etiology being identified. Viral infections cause a great many cases.
Treatment is with aspirin, NSAIDs or colchicine. Steroids should be avoided unless cases are refractory to the above-mentioned treatments or if the underlying etiology is best treated by steroid administration (SLE, sarcoidosis, rheumatoid arthritis, etc). When using NSAIDs, ibuprofen (800 mg TID) is preferred over indomethacin because the former increases coronary flow whereas the latter decreases perfusion. Even after appropriate treatment and resolution of the acute event, pericarditis may be a recurrent phenomenon. In cases of post myocardial infarction pericarditis, patients should be hospitalized and started on aspirin (650 mg QID to six times daily). Avoidance of steroids and NSAIDs is prudent as they might adversely affect myocardial scarring and promote aneurysm formation. Anticoagulants should be discontinued in this patient population.