The endocardial extent of reperfused first-time myocardial infarction is more predictive of pathologic Q waves than is infarct transmurality: a magnetic resonance imaging study

Clin Physiol Funct Imaging. 2007 Mar;27(2):101-8. doi: 10.1111/j.1475-097X.2007.00723.x.

Abstract

Background: Historically, Q-wave myocardial infarction (MI) has been equated with transmural MI. This association have, however, recently been rejected. The endocardial extent of MI is another potential determinant of pathological Q waves, since the first part of the QRS complex where the Q wave appears reflects depolarization of subendocardial myocardium. Therefore, the aim of the present study was to test the hypothesis that endocardial extent of MI is more predictive of pathological Q waves than is MI transmurality and to investigate the relationship between QRS scoring of the ECG and MI characteristics.

Methods: Twenty-nine patients with reperfused first-time MI were prospectively enrolled. One week after admission, delayed contrast-enhanced magnetic resonance imaging (DE-MRI) was performed and 12-lead ECG was recorded. Size, transmurality and endocardial extent of MI were assessed by DE-MRI. Q waves were identified with Minnesota coding and electrocardiographic MI size was estimated by QRS scoring of the ECG.

Results: There was a significant difference between patients with and without Q waves with regard to MI size (P = 0.03) and endocardial extent of MI (P = 0.01), but not to mean and maximum MI transmurality (P = 0.09 and P = 0.14). Endocardial extent was the only independent predictor of pathological Q waves. Endocardial extent of MI was most strongly correlated to QRS score (r = 0.86, P<0.001) of the MI variables tested.

Conclusion: The endocardial extent of reperfused first-time acute MI is more predictive of pathological Q waves than is MI transmurality.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Electrocardiography*
  • Endocardium / pathology*
  • Endocardium / physiopathology
  • Female
  • Heart Conduction System / physiopathology*
  • Humans
  • Logistic Models
  • Magnetic Resonance Imaging*
  • Male
  • Middle Aged
  • Myocardial Infarction / diagnosis*
  • Myocardial Infarction / pathology
  • Myocardial Infarction / physiopathology
  • Myocardial Infarction / surgery
  • Myocardial Reperfusion*
  • Odds Ratio
  • Predictive Value of Tests
  • Prospective Studies
  • Research Design