Defibrillator with shock energy based on EKG transform

US5643325A · kind A · utility

Assignee

• Cedars Sinai Medical Center · US

Inventors

• Hrayr S. Karagueuzian · Los Angeles, US
• George A. Diamond · Los Angeles, US
• Steven S. Khan · Los Angeles, US
• Timothy A. Denton · Los Angeles, US
• Steven Evans · Great Neck, US

Key dates

• Filing date: Jan 24, 1996
• Grant date: Jul 1, 1997
• Expiry date: Jan 24, 2016

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61B5/7239
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

A method for detecting a heart disorder comprises examination of a phase-plane plot (PPP) of a patient electrocardiogram (EKG). The PPP's degree of deterministic chaos may be measured by a processor. Analysis of the PPP may indicate a propensity for fibrillation that is, indicate both the risk of fibrillation and its actual onset (cases where risk is 100 percent). A second method for detecting a heart disorder comprises examination of a frequency-domain transform (such as an FFT) of a patient EKG. An automatic defibrillating device may comprise means for delivering a variable shock, the size of which is determined at least in part by the FFT's peak energy. A method for detecting drug toxicity comprises examination of a parameter time constant for an action-potential duration (APD) restitution curve which is constructed for the patient.