Atrial repolarization: its role in ST elevation.

Puletti M, Curione M, Pozzar F, Righetti G, Jacobellis G

J Electrocardiol. 1979 Jul;12(3):321-4. doi: 10.1016/s0022-0736(79)80067-9.

In four patients, ectopic supraventricular rhythm (or beats) with cephalad anomalous atrial activation and, generally, a short PR, were always associated with an ST elevation in the leads with a negative P wave. An inverted Ta wave appears to be responsible for the ST elevation.