Patent ID: 7039457

Claim:
A method for treating a victim of possible cardiac arrest, usually due to a heart attack, by applying chest compressions to the victim and by monitoring of ECG (electrocardiogram) signals of the victim by a control of an AED (automatic external defibrillator) to determine whether or not to operate the AED to deliver a defibrillator shock to the victim, comprising: continuing to apply chest compressions to the victim while generating corrupted ECG signals that are corrupted by chest compression artifacts; analyzing, by the control of the AED, the corrupted ECG signals that are corrupted by chest compression artifacts to determine whether or not to operate the AED to deliver a defibrillating shock; said step of analyzing the corrupted ECG signals includes analyzing intermediate portions of the ECG signal that lie between successive chest compression artifacts but not portions of the ECG signals that include the chest compression artifacts, and identifying QRS complexes in short periods between successive chest compression artifacts, including detecting two successive signal portions in said short periods of the ECG signal that are of opposite large slopes and large changes in amplitudes; wherein said large changes in amplitudes are at least 10 percent of a change in amplitude of the chest compression artifacts.