Comparison of high-frequency QRS components and ST-segment elevation to detect and quantify acute myocardial ischemia
Michael Ringborn1, Jonas Pettersson, Eva Persson
1Department of Cardiology, Lund University, Lund, Sweden. michael.ringborn@ltblekinge.se
Insights
High-frequency components of the depolarization phase (HF-QRS) show greater ability to detect and quantify myocardial ischemia compared to traditional ST-elevation criteria. HF-QRS analysis offers valuable insights into acute ischemia detection and risk area quantification.
Area of Science:
- Cardiology
- Biomedical Engineering
- Medical Diagnostics
Background:
- Myocardial ischemia detection and quantification are critical in cardiovascular medicine.
- Conventional ST-elevation criteria have limitations in accurately assessing ischemia.
- Novel electrocardiogram (ECG) analysis methods are needed for improved diagnostic accuracy.
Purpose of the Study:
- To compare the efficacy of high-frequency components of the depolarization phase (HF-QRS) with standard ST-elevation criteria for detecting and quantifying myocardial ischemia.
- To evaluate the correlation between HF-QRS changes and ST-segment elevation with the extent and severity of ischemia.
Main Methods:
- Twenty-one patients undergoing percutaneous coronary intervention were studied.
- Myocardial scintigraphy was used for ischemia quantification.
- High-resolution ECGs were recorded, and HF-QRS (150-250 Hz) and ST-segment deviation (<100 Hz) were analyzed.
Main Results:
- HF-QRS criteria were met by 76% of patients, significantly higher than ST-elevation criteria (38%, P = .008).
- Both HF-QRS reduction (r = 0.59-0.69) and ST elevation (r = 0.49-0.57) correlated significantly with ischemia extent and severity.
- HF-QRS demonstrated a stronger correlation with ischemia severity than ST elevation.
Conclusions:
- HF-QRS analysis shows promise as a valuable tool for detecting acute myocardial ischemia.
- HF-QRS provides quantitative information regarding the myocardial area at risk.
- This technique may enhance the diagnostic capabilities beyond conventional ECG methods.
Objective:
This study tests the ability of high-frequency components of the depolarization phase (HF-QRS) vs conventional ST-elevation criteria to detect and quantify myocardial ischemia.
Methods:
Twenty-one patients admitted for elective percutaneous coronary intervention were included. Quantification of the ischemia was made by myocardial scintigraphy. High-resolution electrocardiogram before and during percutaneous coronary intervention was recorded and signal averaged. The HF-QRS were determined within the frequency band 150 to 250 Hz. ST-segment deviation was measured in the standard frequency range (<100 Hz).
Results:
HF-QRS criteria were met by 76% of the patients, whereas 38% met the ST-elevation criteria (P = .008). Both HF-QRS reduction and ST elevation correlated significantly with the amount of ischemia (HF-QRS: r = 0.59, P = .005 for extent and r = 0.69, P = .001 for severity; ST elevation: r = 0.49, P = .023 for extent and r = 0.57, P = .007 for severity).
Conclusions:
This study suggests that HF-QRS analysis could provide valuable information both to detect acute ischemia and to quantify myocardial area at risk.
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