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Diagnostic value of R-wave amplitude increase during treadmill exercise testing for detecting coronary artery disease
H Miyakoda1, H Kitamura, T Kinugawa
1First Department of Internal Medicine, Tottori University School of Medicine, Yonago, Japan.
Insights
An exercise-induced increase in R-wave amplitude (RWA) can help detect coronary artery disease (CAD). New criteria analyzing RWA patterns during exercise and recovery show 86% accuracy in diagnosing CAD.
Area of Science:
- Cardiology
- Diagnostic Imaging
- Exercise Physiology
Background:
- Coronary artery disease (CAD) diagnosis often relies on invasive procedures.
- Non-invasive markers for CAD detection are continuously being investigated.
- Exercise-induced changes in electrocardiogram (ECG) parameters are potential indicators of myocardial ischemia.
Purpose of the Study:
- To assess the diagnostic utility of exercise-induced R-wave amplitude (RWA) changes for detecting coronary artery disease (CAD).
- To establish novel criteria for CAD detection based on serial RWA patterns during treadmill testing.
- To correlate abnormal RWA changes with potential underlying cardiac dysfunction.
Main Methods:
- Treadmill testing utilizing the modified Bruce protocol was conducted on a CASE II computerized system.
- Participants included healthy individuals, patients with confirmed CAD, and subjects with valvular heart disease.
- Analysis focused on serial changes in RWA in lead V5 during exercise and recovery phases.
Main Results:
- New criteria for RWA changes during exercise and recovery were proposed.
- A combination of these RWA criteria demonstrated 86% sensitivity, specificity, and accuracy for CAD detection.
- Abnormal RWA increases were potentially linked to increased left ventricular (LV) end-diastolic volume due to exercise-induced LV dysfunction.
Conclusions:
- Exercise-induced RWA increase is a valuable, non-invasive indicator for detecting coronary artery disease (CAD).
- Considering the patterns of serial RWA changes significantly enhances diagnostic accuracy.
- Abnormal RWA responses may reflect exercise-induced left ventricular dysfunction.
Abstract:
To evaluate the diagnostic value of an exercise-induced increase in R-wave amplitude (RWA) for detecting coronary artery disease (CAD), treadmill testing using the modified Bruce protocol was performed on a CASE II computerized system (Marquette) in 10 healthy young men, 35 patients (pts) with CAD, 22 subjects with normal coronary arteries, and 11 pts with aortic or mitral regurgitation. Based on the analysis of the patterns of serial changes in RWA in lead V5, we proposed new RWA criteria for detecting CAD. (1) During exercise, RWA increases in stage 1 and subsequently increases further or remains unchanged. (2) During exercise, RWA decreases in the early phase of exercise and subsequently increases. (3) In the recovery period, RWA shows a gradual and excessive increase. A combination of the above RWA criteria showed a sensitivity, specificity and accuracy of an equal value of 86%. We conclude that an exercise-induced RWA increase is a useful indicator for detecting CAD, especially when taking the patterns of serial changes into consideration, and that the abnormal RWA increase may be related to an increase in left ventricular (LV) end-diastolic volume due to exercise-induced LV dysfunction.