DIAGNOSIS: NSR. Acute Pericarditis.

EXPLANATION: Normal sinus rhythm at rate of 90. Diffuse ST segment elevations are noted especially in leads II, aVF, V2-V6, with concavity upwards. PR segment depressions are noted in several leads as well; very clearly in lead II. The above changes are classic for acute pericarditis. Only a scant majority of cases of pericarditis will have such a diagnostic tracing however. Differentiating the ST changes of pericarditis from those of ischemia and early repolarization may be problematic. The lack of reciprocal ST depressions helps with regard to ischemia. Early repolarization usually is not present in both the limb leads and the precordial leads. In V6 if the apex of the T wave is less than 4 times the height of the onset of the ST segment, this is a point against early repolarization. In this case, since the history is that of a 27 year old male with sharp pleuritic chest pain worse when lying supine, the diagnosis becomes somewhat less obscure! One last point: arrythmias appear to be relatively uncommon in these cases. Thanks to Dr Jim Ungar for the EKG.

Editor: Sol Nevins MD FACEP. Faculty, Emergency Medicine Residency, Morristown Memorial Hospital, Morristown, N.J.