Copyright © 1993 by the European Society of Cardiology.
© 1993 The Europen Society of Cardiology
The electrocardiographic diagnosis of regional pericarditis in acute inferior myocardial infarction
*Rose Medical Center Denver, CO, U.S.A.
Electrocardiographic and Electrophysiologic Laboratories, Division of Cardiology Rochester, MN, U.S.A.
Department of Pathology, Mayo Clinic and Mayo Foundation Rochester, MN, U.S.A.
Received 5 March 1993; revised 24 June 1993; .
Correspondence: Philip B, Oliva, MD, Cardiology Division, Rose Medical Center, 4567 E. Ninth Avenue, Denver, CO 80220, U.S.A.
Abstract
The diagnosis of postinfarction localized (regional) pericarditis has remained elusive. During the course of a recent study of patients with fatal free-wall rupture, an atypical pattern of T-wave evolution was observed during the days preceding death. It was learned, from autopsy examination, that these electrocardiographic changes were due to the associated localized pericarditis, rather than the rupture, per se. Therefore, this investigation was undertaken to ascertain if the same atypical T-wave changes occur in patients with postinfarction localized pericarditis, but without free-wall rupture, and to determine if the frequency of those changes differs between those patients with inferior and those with anterior postinfarction pericarditis.
Forty-three patients with regional postinfarction pericarditis were identified clinically. They were divided into three groups, anterior (17), inferior (17) and lateral or posterior (9) myocardial infarction. In this report those patients with anterior regional postinfarction pericarditis are compared with those with inferior postinfarction pericarditis. It was found that an atypical T-wave evolution pattern — either persistently positive T-waves after 48 h or reversal of initially inverted T-waves after 48 h — existed in every patient irrespective of infarct location.
However, the two atypical patterns of T-wave evolution occurred with distinctly different frequencies between the two sites of infarction. With inferior post infarction pericarditis, gradual reversal of initially inverted T-waves occurred in 14 patients (82%) while only three (18%) had persistently positive T-waves. Conversely, among patients with anterior postinfarction pericarditis, reversal after inversion occurred in five of 17 patients (29%) while 12 of 17 patients (71%) had persistently positive deflections (P<0.01).
The only other processes observed which affected the T-wave evolution in a similar manner were patients who had had cardiopulmonary resuscitation performed and four patients with very small, initial infarcts who had rapid reversal of initially inverted T-waves due to the very early administration of lytic therapy. Therefore, atypical postinfarction T-wave evolution is a very sensitive (100%) and reasonably specific (77%) sign of postinfarction regional pericarditis.
Key Words: Postinfarction pericarditis • persistently positive T-waves • reversal of initially inverted T-waves