Clinical Communications: Adults
ST-Elevation Myocardial Infarction in the Presence of Biventricular Paced Rhythm

https://doi.org/10.1016/j.jemermed.2013.03.034Get rights and content

Abstract

Background

In the diagnosis of acute myocardial infarction (AMI), the presence of baseline left bundle branch block or a permanent pacemaker rhythm poses a challenge.

Objective

We present a case report highlighting this challenge, along with a review of pertinent literature.

Case Report

A 70-year-old female with known severe idiopathic dilated cardiomyopathy and moderate coronary artery disease who was status post−biventricular pacemaker/implantable cardioverter defibrillator insertion was brought to our institution via Emergency Medical Services with recurrent firing of her implantable cardioverter defibrillator and syncope. After stabilization in the Emergency Department and treatment with intravenous amiodarone, the patient admitted to having ongoing chest pains. The electrocardiogram revealed evidence of biventricular pacing with superimposed ST-segment elevations in the anterolateral leads indicative of myocardial injury. She underwent prompt angiography, thrombectomy, and bare-metal stent insertion to a totally occluded proximal left anterior descending coronary artery, with resolution of her chest pain and improvement in the ST-segment changes.

Conclusions

Despite proposed criteria that aid in the recognition of AMI with underlying left bundle branch block and paced rhythm; the advent of new pacing modalities and the potential variability of pacing sites impose additional diagnostic challenges requiring higher level of suspicion and better physician awareness.

Introduction

ST-segment elevation myocardial infarction (STEMI) is a serious condition requiring prompt electrocardiographic recognition because prognosis is highly dependent on timely reperfusion (1). The electrocardiographic manifestations are, for the most part, obvious and readily recognizable (2). However, in the presence of baseline abnormalities on the electrocardiogram (ECG), such as bundle branch blocks, especially left bundle branch block (LBBB), or a permanent pacemaker rhythm, the electrocardiographic diagnosis becomes challenging and requires additional skills and a high level of suspicion (3). We report a case of anterolateral MI in a patient with biventricular pacing, which presents another challenge because such devices are increasingly implanted in combination with an implantable cardioverter defibrillator (ICD) in patients with congestive heart failure, who are expected to pace the majority of the time to reap the benefits of synchronization.

Section snippets

Case Report

A 70-year-old female with known severe idiopathic dilated cardiomyopathy was brought to our Emergency Department (ED) by Emergency Medical Services after an episode of loss of consciousness at home, followed by firing of her ICD. Two and a half years earlier, she underwent cardiac catheterization as part of the workup for severe cardiomyopathy, which showed an ejection fraction of 15%−20%. Her coronary angiogram revealed 40% mid−left anterior descending (LAD) and 50%−60% ostial first diagonal

Discussion

Balotin, in a review article on MI diagnosis and treatment in 1959, wrote in the summary, “In patients suffering an attack of myocardial infarction the history and symptoms are often sufficient to make a tentative diagnosis. Serial changes in the electrocardiogram are valuable but not essential” (4). The role of the ECG has since come a long way toward being a pivotal tool in the diagnosis of chest pain; the results of ECG often determine the critical management of an acute coronary syndrome (2)

Conclusions

The ECG remains the cornerstone for the diagnosis and timely decision making in AMI. Its utility, however, has often been blurred by the presence of underlying abnormalities that can mask the classic anticipated ST-segment elevation. Criteria have been proposed to aid in the diagnosis of AMI with underlying LBBB and paced rhythm. Biventricular pacing, and the potential variability of pacing sites, causes ECG patterns different from conventional RV apical pacing, which can impact the recognition

References (29)

  • S.S. Barold et al.

    Diagnostic value of the 12-lead electrocardiogram during conventional and biventricular pacing for cardiac resynchronization

    Cardiol Clin

    (2006)
  • M. Refaat et al.

    Electrocardiographic characteristics in right ventricular vs biventricular pacing in patients with paced right bundle-branch block QRS pattern

    J Electrocardiol

    (2011)
  • E.M. Antman et al.

    ACC/AHA guidelines for the management of patients with ST-elevation myocardial infarction: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines

    Circulation

    (2004)
  • P.J. Zimetbaum et al.

    Use of the electrocardiogram in acute myocardial infarction

    N Engl J Med

    (2003)

    • Cited by (12)

    • Smith-Modified Sgarbossa Criteria and Paced Rhythms: A Case Report

      2016, Journal of Emergency Medicine
      Citation Excerpt :

      Although the ECG morphology of some paced rhythms are similar to LBBB rhythms, no formal study has documented the application of Sgarbossa criteria in the presence of paced rhythms. There are, however, published case reports of the application of Sgarbossa criteria in paced rhythms (3–5). To add to this growing body of knowledge, we present a case of STEMI diagnosed in the context of a paced rhythm using the Smith-modified Sgarbossa criteria.

    • St segment elevation myocardial infarction in biventricular paced rhythm

      2014, Heart Lung and Circulation
      Citation Excerpt :

      Repeat ECG showed ST segment returned to almost baseline (Fig. 2) with the exception that R wave amplitude in V1 never came to baseline, which could not be explained. On reviewing the literature we found only two case reports addressing diagnosis of STEMI in patients with biventricular-paced rhythm [3,4]. The clinical presentation, ECG changes and angiographic results of the identified cases and that of ours are summarised in Table 1s. Cases 1 and 3 fulfilled both Sgarbossa criteria for > 1 mm concordant (QRS complex and T wave in same direction) ST elevation while neither fulfilled criteria for > 5 mm discordant (QRS complex and T wave in opposite direction) ST elevation.

    • Difficult ECGs in STEMI: Lessons learned from serial sampling of pre- and in-hospital ECGs

      2014, Journal of Electrocardiology
      Citation Excerpt :

      Biventricular pacing is another challenge. Two recent case reports underline the usefulness of serial ECGs in diagnosing STEMI in that particular setting and emphasize the need for further investigation. [37,38]. Like in LBBB, in the absence of specific criteria for ongoing transmural ischemia, patients with symptoms suggestive of AMI and paced ventricles need further risk stratification in an invasive center that may perform cardiac biochemical marker analysis, bedside echocardiography or possibly immediate coronary catheterization.

    • AMI in (bi)ventricular pacing–do not discard the ECG

      2023, Acta Clinica Belgica: International Journal of Clinical and Laboratory Medicine

    • Diagnosis of Occlusion Myocardial Infarction in Patients with Left Bundle Branch Block and Paced Rhythms

      2021, Current Cardiology Reports

    • Anterior wall ST-elevation myocardial infarction in biventricular paced rhythm

      2020, Herzschrittmachertherapie und Elektrophysiologie
    View all citing articles on Scopus
    View full text
    Copyright © 2013 Elsevier Inc. All rights reserved.