Atrial Repolarization Waves (T_a) Mimicking Inferior Wall ST Segment Elevation Myocardial Infarction in a Patient with Ectopic Atrial Rhythm

Abstract

We present a case of atrial repolarization waves from an ectopic atrial rhythm mimicking inferior ST segment elevation myocardial infarction in a 78-year-old male patient who presented with left sided chest wall and shoulder pain. His ischemic workup was negative, and the ST elevations completely resolved upon the resumption of sinus rhythm before discharge.

Retrospective evaluation of the ST segment electrocardiographic features in 180 healthy dogs

“…In patients with normal sinus rhythm, Ta wave has a very minimal impact on the surface electrocardiogram since the QRS complex normally obscures its evidence on tracings (as, physiologically, they occur almost simultaneously and the Ta wave has a very low amplitude; mean value in dogs, −0.09 mV) (Perego et al 2014,Srour & Hyder 2014, Manne 2018). However, the Ta wave may become evident in patients with some disturbances of cardiac rhythm, including short and long PR intervals, second-degree and third-degree atrioventricular blocks and ectopic atrial rhythms (Perego et al 2014, Srour & Hyder 2014, Manne 2018. In these cases, the Ta wave may superimpose on the ST segment and alter its morphology and/or amplitude (Srour & Hyder 2014, Manne 2018.…”

“…However, the Ta wave may become evident in patients with some disturbances of cardiac rhythm, including short and long PR intervals, second-degree and third-degree atrioventricular blocks and ectopic atrial rhythms (Perego et al 2014, Srour & Hyder 2014, Manne 2018. In these cases, the Ta wave may superimpose on the ST segment and alter its morphology and/or amplitude (Srour & Hyder 2014, Manne 2018. However, such a risk may be reasonably excluded in the current study population, as all dogs were healthy subjects showing sinus rhythm and normal standard electrographic parameters.…”

“… 2014 , Srour & Hyder 2014 , Manne 2018 ). In these cases, the Ta wave may superimpose on the ST segment and alter its morphology and/or amplitude (Srour & Hyder 2014 , Manne 2018 ). However, such a risk may be reasonably excluded in the current study population, as all dogs were healthy subjects showing sinus rhythm and normal standard electrographic parameters.…”