Electrocardiographic abnormalities in acute pericarditis. Diffuse up-sloping ST-segment elevation is seen in leads I, II, aVF, and V1 to V6. The PR segment is elevated in the aVR lead (arrows) and subtly depressed in leads I, II, aVF, and V2 to V6 (arrowheads). Reciprocal ST-segment depression is seen in the aVR lead.