Comparison of high-frequency QRS components and ST-segment elevation to detect and quantify acute myocardial ischemia.
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.
Ringborn
Michael
M
Department of Cardiology, Lund University, Lund, Sweden. michael.ringborn@ltblekinge.se
Pettersson
Jonas
J
Persson
Eva
E
Warren
Stafford G
SG
Platonov
Pyotr
P
Pahlm
Olle
O
Wagner
Galen S
GS
D000368:Aged; D000465:Algorithms; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D017202:Myocardial Ischemia / Q000175:diagnosis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity