Electrocardiogram parameters in predicting reversible ischemia in myocardial perfusion SPECT: A case-control study

Area of Science:

• Cardiology
• Medical Imaging
• Electrophysiology

Background:

• Myocardial perfusion SPECT and ECG are key for evaluating coronary artery disease (CAD).
• Understanding ventricular repolarization's link to ischemia is crucial for CAD assessment.

Purpose of the Study:

• To assess the relationship between ECG-derived ventricular repolarization parameters, including the index of cardiac electrophysiological balance (iCEB), and reversible ischemia detected by SPECT.
• To identify ECG predictors of reversible ischemia in patients with confirmed CAD.

Main Methods:

• Compared ECG parameters (QRS, QTd, cQTd, Tp-Te, Tp-Te/QT, Tp-Te/cQT, iCEB, iCEBc) in 45 patients with reversible ischemia on SPECT and 45 controls.
• Utilized 99m technetium-sestamibi (99mTc-MIBI) stress-rest SPECT and coronary angiography for diagnosis and assessment.
• Correlations were analyzed using Spearman test; predictors of reversible ischemia were identified via logistic regression.

Main Results:

• Patients with ischemia showed significantly longer QRS duration, cQTmax, QTd, and cQTd.
• The ischemia group had significantly lower Tp-Te, Tp-Te/QT, and Tp-Te/cQT ratios.
• Multivariate analysis identified hyperlipidemia, QRS duration, cQTd, and Tp-Te/QTc ratio as independent predictors of ischemia.

Conclusions:

• The Tp-Te/cQT ratio, QRS duration, and cQTd show potential as valuable predictors of reversible ischemia in SPECT.
• Further research is warranted to validate these ECG parameters for predicting reversible ischemia in CAD.