NOISE DETECTION AND FREQUENCY DETERMINATION IN AN EXTRA-CARDIOVASCULAR IMPLANTABLE CARDIOVERTER DEFIBRILLATOR SYSTEM

摘要

An extra-cardiovascular implantable cardioverter defibrillator is configured to store a cardiac signal segment in response to sensing a cardiac event and obtain a notch filtered signal segment by notch filtering the cardiac signal segment. The ICD determines a count of crossings of the notch filtered signal segment by the cardiac signal segment and determines whether electromagnetic interference (EMI) is present in the cardiac signal segment based on a value of the count.