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Related Experiment Video

Updated: Jul 27, 2026

Methods for ECG Evaluation of Indicators of Cardiac Risk, and Susceptibility to Aconitine-induced Arrhythmias in Rats Following Status Epilepticus

Methods for ECG Evaluation of Indicators of Cardiac Risk, and Susceptibility to Aconitine-induced Arrhythmias in Rats Following Status Epilepticus

Published on: April 5, 2011

Changes in QT dispersion during adenosine infusion.

A Kumar¹, C Narasimhan, A Sankari

¹Dept. of Cardiology, Michael Reese Hospital, Chicago, IL 60616, USA.

Clinical Cardiology

|November 4, 2000

Summary

QT dispersion (QTd) changes during adenosine stress tests can help detect coronary artery disease (CAD). A significant increase in QTd during the test indicates CAD and improves ECG accuracy for diagnosis.

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Interventional Diagnostic Procedure: A Practical Guide for the Assessment of Coronary Vascular Function

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Published on: March 15, 2022

Area of Science:

Cardiology
Diagnostic Imaging
Electrocardiography

Background:

QT dispersion (QTd) measurement during treadmill stress testing enhances exercise electrocardiogram (ECG) accuracy for detecting coronary artery disease (CAD).
Adenosine stress testing is a common method for evaluating suspected CAD.

Purpose of the Study:

To determine if adenosine-induced changes in QTd can predict significant CAD.
To assess the efficacy of QTd as a diagnostic index in patients undergoing adenosine stress testing.

Main Methods:

QT interval measurements were performed on 57 patients during adenosine sestamibi stress tests.
Patients with abnormal stress tests underwent coronary angiography to define significant CAD (>70% stenosis).
Patients were classified into CAD (Group 1) and no CAD (Group 2) based on angiography results.

Main Results:

QT dispersion significantly increased in patients with CAD (delta QTd = 15.53 ms) compared to those without CAD (delta QTd = 6.58 ms) during adenosine infusion.
Adding delta QTd (>10 ms) to ST depression analysis increased ECG sensitivity for CAD detection from 23% to 65%, while specificity decreased from 91% to 70%.

Conclusions:

A significant increase in QTd during adenosine infusion is indicative of CAD.
Delta QTd serves as a valuable adjuvant index, enhancing the sensitivity of stress ECG for diagnosing CAD.