초록 ▼

A cardiac event and arrhythmia detection system and method detects arrhythmic cardiac activity or other information from an electrogram signal of a heart. The system senses the electrogram signal through an electrogram lead, preliminarily processes the signal, and converts it to a plurality of discr

A cardiac event and arrhythmia detection system and method detects arrhythmic cardiac activity or other information from an electrogram signal of a heart. The system senses the electrogram signal through an electrogram lead, preliminarily processes the signal, and converts it to a plurality of discrete digital signals, each of which represents the magnitude of the electrogram signal at a prescribed sample time. The discrete digital signals are applied to both a cardiac event detector which has a dynamic threshold which is programmably adjustable so that T-waves are not sensed and a morphology detector. The morphology detector detects selected changes in the morphology (shape) of the electrogram signal, wherein such changes automatically control the sensitivity (gain and/or threshold) used to detect cardiac events. The occurrence of a prescribed amount of change in the detected morphology over time indicates the occurrence of a prescribed arrhythmic cardiac condition.

대표청구항 ▼

An implantable cardiac event detection system for eliminating sensing of high amplitude T-waves, the system including an implantable lead that transmits an electrogram signal from a heart, comprising: an amplifier, coupled to the implantable lead, for amplifying an electrogram signal; threshold dete

An implantable cardiac event detection system for eliminating sensing of high amplitude T-waves, the system including an implantable lead that transmits an electrogram signal from a heart, comprising: an amplifier, coupled to the implantable lead, for amplifying an electrogram signal; threshold detection means, coupled to the amplifier, for detecting an occurrence of an R-wave in the electrogram signal whenever the magnitude of the electrogram signal exceeds a threshold value; timing means for generating a delay period following the detection of an R-wave; and control means, responsive to the detection of the R-wave, for dynamically changing the threshold value from an initial value to a temporary value following the delay period, and then gradually returning the threshold value from the temporary value back to the initial value in accordance with a prescribed slope, so that a high amplitude T-wave that follows the R-wave is not sensed.