<unk> <unk>  refers to the analysis of the<unk><unk>  spectral components of the QRS complex in an electrocardiogram (ECG).<unk><unk>  analysis of the QRS complex may be useful for detection of coronary artery disease during an exercise stress test. It however requires special software. __TOC__
High frequency QRS
Electrical alternans
T wave alternans
Spike-and-wave
J wave
Cannon A waves
QRS complex
Apex beat