Normal Variant ST‐Segment Morphology or Pericarditis?

Abstract

Ann Noninvasive Electrocardiol 2011;16(4):415

Dear Editor,

I have read with interest the article by Roukoz and Wang concerning rare normal variants of ST‐segment elevation published in the recent issue of your Journal. ¹

The ECG showing an example of the variant ST‐segment morphology (Fig. 1B) additionally shows pronounced PR segment depression in leads I, II, aVF, and V₂–V₆, and PR segment elevation in aVR. However, this was not referred to in the paper.

I believe that the presence of such a significant PR segment depression raises several important issues: (1) What was the frequency of this ECG feature among the 101 reported ST‐T‐variant cases? (2) How can this pattern be differentiated from acute pericarditis, and how did the authors determine that the identified ST‐T‐variant patients were not pericarditis cases? Were consecutive ECGs (at least few weeks apart) analyzed with regard to the presence of ST‐T evolution?

The authors seemed to underplay this problem by stating, “In pericarditis the ST segment is more diffused, the PR segment depression is more distinct and T waves are usually not inverted when ST segments are elevated.” However, having seen a fair number of pericarditis cases, I am convinced that PR depression in pericarditis is often similar or even less pronounced in comparison to the ST‐variant ECG shown in Figure 1B, and that ST‐segment elevation is often not more widespread, and that T waves might invert while the ST segment is still markedly elevated. ² It seems, therefore, that this ST variant cannot be differentiated from pericarditis unless serial ECGs over a longer time span are available to exclude ST‐T evolution.