title: The Guardian: an implantable system for chronic ambulatory monitoring of acute myocardial infarction.
abstract: The AngelMed Guardian is an implantable medical device that records cardiac data and detects ischemic events using a standard pacemaker intracardiac lead positioned in the right ventricular apex. The Guardian has been implanted in 55 people in the United States and Brazil and is currently undergoing a Food and Drug Administration phase 2 pivotal trial in the United States. The Guardian detects acute ischemic events by analyzing ST-segment shifts. The ST-segment shifts are calculated as the difference between the ST deviation of a current 10-second electrogram window and a baseline ST deviation value. If the ST-segment shift is greater than a heart rate-dependent programmable threshold, then the device generates an emergency alert signal. Results thus far have demonstrated that (i) the intracardiac electrogram is relatively noise-free and (ii) the ST-shift technique used by the Guardian is effective for detecting acute ischemic events.
authors.affiliation: Angel Medical Systems, 1163 Shrewsbury Ave., Shrewsbury, NJ 07702, USA. brhopenfeld@yahoo.com
authors.forename: Bruce
authors.initials: B
authors.lastname: Hopenfeld
authors.forename: M Sasha
authors.initials: MS
authors.lastname: John
authors.forename: David R
authors.initials: DR
authors.lastname: Fischell
authors.forename: Paulo
authors.initials: P
authors.lastname: Medeiros
authors.forename: Hélio P
authors.initials: HP
authors.lastname: Guimarães
authors.forename: Leopoldo S
authors.initials: LS
authors.lastname: Piegas
mesh_terms: D000818:Animals; D003936:Diagnosis, Computer-Assisted / Q000295:instrumentation* / Q000379:methods; D015716:Electrocardiography, Ambulatory / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000517:prevention & control*; D010138:Pacemaker, Artificial; D019736:Prostheses and Implants; D013552:Swine