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A Research Method For Detecting Transient Myocardial Ischemia In Patients With Suspected Acute Coronary Syndrome Using Continuous ST-segment Analysis
18:11

A Research Method For Detecting Transient Myocardial Ischemia In Patients With Suspected Acute Coronary Syndrome Using Continuous ST-segment Analysis

Published on: December 28, 2012

QRS prolongation in patients with acute coronary syndromes

Fahad Baslaib1, Salem Alkaabi, Andrew T Yan

  • 1Division of Cardiology, St Michael's Hospital, University of Toronto, Toronto, Canada.

American Heart Journal
|April 6, 2010
PubMed

Insights

QRS prolongation, especially with left bundle branch block (LBBB), independently predicts mortality in acute coronary syndrome (ACS) patients. This finding highlights the prognostic value of ECG findings in ACS management.

Area of Science:

  • Cardiology
  • Electrocardiography
  • Clinical Outcomes

Background:

  • QRS prolongation and bundle branch block (BBB) are linked to adverse outcomes in myocardial infarction.
  • The prognostic significance of QRS duration in acute coronary syndrome (ACS) requires further investigation.

Purpose of the Study:

  • To examine the relationship between QRS duration and patient outcomes in a wide range of ACS patients.
  • To determine if QRS prolongation, with or without BBB, is an independent predictor of mortality.

Main Methods:

  • Core laboratory analysis of presenting electrocardiograms from 5,003 Canadian ACS Registry patients.
  • Categorization of patients based on QRS duration (<120 ms, ≥120 ms without BBB, LBBB, RBBB).
  • Statistical analysis to assess in-hospital and 1-year mortality, including odds ratios and confidence intervals.

Main Results:

  • Patients with QRS ≥120 ms without BBB had higher in-hospital and 1-year mortality compared to those with QRS <120 ms.
  • Patients with BBB (LBBB or RBBB) showed significantly higher in-hospital and 1-year mortality.
  • QRS duration, analyzed continuously, was an independent predictor of 1-year death and death/myocardial infarction.
  • Left bundle branch block (LBBB) emerged as the sole independent predictor of 1-year mortality when using clinically applicable QRS evaluation.

Conclusions:

  • QRS prolongation, particularly with LBBB, is a significant independent predictor of mortality in patients with suspected ACS.
  • ECG findings like QRS duration and LBBB provide crucial prognostic information in ACS.
  • These findings support the integration of detailed ECG analysis into risk stratification for ACS patients.
Abstract

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