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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

Changes of QRS axis in transient myocardial ischaemia induced by percutaneous transluminal coronary angioplasty

K Shirota1, K Ogino, A Hoshio

  • 1First Department of Internal Medicine, Tottori University School of Medicine, Yonago, Japan.

European Heart Journal
|October 1, 1994
PubMed

Insights

Transient left axis deviation during PTCA indicates proximal LAD occlusion with septal branch involvement. Transient right axis deviation suggests RCA occlusion in coronary artery disease patients.

Area of Science:

  • Cardiology
  • Electrophysiology

Background:

  • Coronary artery disease (CAD) affects cardiac electrical activity.
  • Percutaneous transluminal coronary angioplasty (PTCA) is a common intervention for CAD.
  • QRS axis shifts can indicate myocardial ischemia or infarction.

Purpose of the Study:

  • To investigate transient QRS axis shifts during PTCA in CAD patients.
  • To correlate specific axis deviations with the location of coronary artery lesions.

Main Methods:

  • Measured QRS axis in 130 CAD patients before and during PTCA.
  • Divided patients into groups based on myocardial infarction history (Group A: no Q waves, Group B: Q waves).
  • Analyzed axis shifts in relation to Left Anterior Descending (LAD), Right Coronary Artery (RCA), and Left Circumflex (LCX) artery occlusions.

Main Results:

  • In Group A, LAD occlusion caused significant leftward QRS axis shift (P < 0.001).
  • RCA occlusion in Group A resulted in significant rightward QRS axis shift (P < 0.01).
  • No significant axis shifts were observed in Group B or with LCX occlusion.

Conclusions:

  • Transient left axis deviation during PTCA signifies proximal LAD occlusion involving the major septal branch.
  • Transient right axis deviation during PTCA indicates an obstructive lesion in the Right Coronary Artery (RCA).

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