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The prognostic value of a QRS score during exercise testing

Andreas P Michaelides1, Maria-Niki K Aigyprladou, George K Andrikopoulos

  • 1Exercise Laboratory, Department of Cardiology, A' Cardiology Clinic, Medical School of Athens University, Hippokration Hospital, Athens, Greece. aigyptiadou@yahoo.gr

Clinical Cardiology
|September 8, 2005
PubMed

Insights

An abnormal QRS score during treadmill exercise testing is a significant predictor of cardiac mortality in patients with coronary artery disease (CAD). This finding highlights the QRS score's clinical value in predicting outcomes for individuals with established CAD.

Area of Science:

  • Cardiology
  • Exercise Physiology
  • Diagnostic Imaging

Background:

  • QRS score values correlate with coronary artery narrowing and myocardial ischemia extent.
  • Radionuclide imaging techniques have previously shown this association.

Purpose of the Study:

  • To assess the prognostic capability of abnormal QRS scores from treadmill exercise tests.
  • To investigate the predictive value of QRS scores in patients with established coronary artery disease (CAD).

Main Methods:

  • 309 patients with documented CAD underwent treadmill exercise testing and coronary arteriography.
  • Patients were prospectively followed for up to 36 months.

Main Results:

  • Abnormal QRS scores (<= -4) were significantly and independently linked to cardiac mortality.
  • A relative risk of 11.7 (p=0.002) was observed for cardiac mortality with abnormal QRS scores.

Conclusions:

  • The QRS score holds clinical utility in predicting outcomes for patients with documented CAD.
  • Incorporating the QRS score into exercise testing can aid in managing ischemic heart disease.
Abstract

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