The ALERTS1 study provided a clinical environment to test the safety and efficacy of the GUARDIAN and highlighted a broad range of benefits to patients, clinicians and the healthcare system.
Reduces time to door
The overall reduction in symptom to door time dropped from a median of 8 hours to 1.7 hours in the treatment group. With STEMI and NSTEMI patients - a fall from a median of 12.7 hours to 1.6 hours.
Detects silent events
The GUARDIAN detected silent ACS events in the study in 41 patients with no symptoms. These patients arrived to door in a medium time of 1.4 hours, prompting early myocardial saving treatment.
Reduces heart damage
GUARDIAN patients that had an occlusive event were less likely to have a decreased Left Ventricular Ejection Fraction at discharge.
Detects other co-morbidities
The Guardian revealed a need for a therapeutic device in 5% of study patients with an overall detection of new serious medical conditions in 8.68% of the study population.
Reduces impact on hospital resources
There was a 26% reduction in the False Positive Rate and unnecessary tests compared to patient symptoms as a trigger for ED visits.
Improves patient quality of life
Patients self reported Quality of Life improved with the GUARDIAN.
Simple implantable device
The GUARDIAN is implanted in an identical manner to a to a single chamber ventricular pacemaker. Adapting to the individual patient the Guardian monitors continuously 24/7 for shifts in ST segment morphology using the Intracardiac Electrogram with a lead positioned in the Right Ventricular Apex.
Following implantation, the GUARDIAN is set to collect data passively over a two-week period. At the end of the two-weeks, adjustments to the detection and alarm criteria are made (much like a post-implant follow-up for a pacemaker).
The data collected is downloaded at follow-up and is also available should an event occur to provide more information on the patient's cardiac activity.
How it works: Proactive healthcare
with the GUARDIAN algorithm
The GUARDIAN’s operation is based on the relationship between ST-segment changes and ischaemia. The GUARDIAN's algorithm continuously monitors the patient’s heart signal for ST-segment changes and provides notification using triple-modality alerting when an abnormal change occurs.
The abnormal change is measured by “ST-Shift”. This shift is the difference between the patient’s current ST-segment and their base-line (learnt from data collected over the previous 24-hours). These shifts can be detected even when a patient is experiencing no symptoms.
Example patient alarm results with the GUARDIAN implant3.
The warning alarm from the GUARDIAN ensured that the patient was admitted to hospital early and was able to receive critical care treatment as soon as an event was detected.
* First Emergency Alarm - Device warning alerted patient to seek immediate medical treatment
** Second Emergency Alarm - Patient's ruptured plaque confirmed by angiogram and other diagnostic tests
2 days prior
11:00:00 am Baseline Patient Electrogram
12 hours prior
12:20:11 pm Emergency Alarm*
4 hours prior
08:25:21 pm Patient in Hospital
Heart Attack Onset
12:06:51 pm Emergency Alarm**
1 month later
05:44:52 pm Post Coronary Bypass
The GUARDIAN delivers value
to all stakeholders
Real-time detection of ACS events
Improvement in Quality of Life
Faster treatment leading to improved outcomes and reduced costs
Reduced costs associated with false positives based on symptoms alone
Paradigm shift in secondary prevention of myocardial damaging ACS events
Increased confidence in patients seeking urgent medical help when needed
Reduction of false positive emergency visitations based on symptoms alone
Cost savings based on reduced long-term myocardial damage
1. Gibson, M., Holmes, D., Mikdadi, G., et al. Implantable Cardiac Alert System for Early Recognition of ST-Segment Elevation Myocardial Infarction. JACC. 2019; 73(15):1919-1927.
2. Holmes, D.R., Krucoff, M.W., Mullin, C., et al. Implanted Monitor Alerting to Reduce Treatment Delay in Patients with Acute Coronary Syndrome Events. JACC. 2019; 74(16):2047-2055.
3. Fischell, T., Fischell, R., Avezum, A., et al. Initial Clinical Results Using Intracardiac Electrogram Monitoring to Detect and Alert Patients During Coronary Plaque Rupture and Ischemia. JACC. 2010 Sep 28; 56(14):1089–98