Confirm Rx® insertable cardiac monitor (ICM)

Introduction: Initial episodes of atrial fibrillation (AF) detected following a cryptogenic stroke (CS) may be brief in duration and the clinical relevance of such episodes is uncertain. Hypothesis: We investigated whether an initial brief episode of AF was predictive of subsequent long duration AF episodes in CS patients (pts) with an insertable cardiac monitor (ICM). Methods: CS pts (n=208, age 61.6±11.3 years, 66% male) randomized to the ICM arm of the CRYSTAL-AF study and inserted with a device (Reveal® XT) were followed for 21±9 months. AF episodes (>30 seconds) were independently adjudicated and the first adjudicated AF episode was classified as brief (<1 hour) or long (≥1 hour). The incidence of subsequent long duration AF episodes among pts with an initially brief episode was computed. The impact of episode duration on prescription of oral anticoagulation (OAC) therapy was also assessed. Results: Among 36 pts with an adjudicated AF episode for which duration information was available, the initial episode was classified as brief in 18 (50%) pts and long in 18 (50%) pts. Among those with initially brief episodes, 10 (56%) experienced only subsequent brief episodes while 8 (44%) went on to experience at least one long AF episode. The median time between the initial brief episode and first long AF episode was 75 days [interquartile range: 27-624 days]. OAC was prescribed in 7/10 pts (70%) with only brief AF episodes compared to 26/26 pts (100%) with at least one long episode of AF (p=0.017). Conclusion: Initial AF episodes in pts with CS are equally likely to be of short or long duration. However, nearly half of CS pts with initially brief episodes of AF subsequently have long duration episodes detected much later via prolonged monitoring with ICMs. Therefore, early detection of brief AF episodes may merit more rigorous monitoring of AF with ICMs since physicians were significantly more likely to prescribe OAC for secondary stroke prevention in response to longer duration episodes.

Download Full-text

Abstract 15666: Effectiveness of Sharpsense™ Algorithms in Reducing Pause and Bradycardia Detection: Real-world Performance Before and After the Software Upgrade in Confirm Rx™ Insertable Cardiac Monitor

Circulation ◽

10.1161/circ.142.suppl_3.15666 ◽

2020 ◽

Vol 142 (Suppl_3) ◽

Author(s):

Rakesh Gopinathannair ◽

Dhanunjaya Lakkireddy ◽

Christopher Piorkowski ◽

Muhammad Afzal ◽

Ghulam Murtaza ◽

...

Keyword(s):

Real World ◽

False Positive ◽

False Positive Rate ◽

Substantial Reduction ◽

Cryptogenic Stroke ◽

Cardiac Monitor ◽

Before And After ◽

Positive Rate ◽

Software Upgrade ◽

Insertable Cardiac Monitor

Background: Recent enhancements have been introduced to the Abbott Confirm Rx™ insertable cardiac monitor (ICM) arrhythmia detection algorithms (SharpSense™). This study aims to characterize the real-world performance of SharpSense™ algorithms, in the upgraded ICM devices by comparing device detected pause and bradycardia (brady) episodes before and after the SharpSense™ upgrade. Methods: Confirm Rx™ devices with at least 90 days monitoring each before and after SharpSense™ upgrade were included in the study. Brady and pause episodes were extracted from Merlin.net™ patient care network for evaluation and adjudicated by expert adjudicators. Results: A total of 197 devices were included in the analysis. Devices were implanted for syncope (35%), AF management (33%), and other indications, including cryptogenic stroke and palpitations (32%). The SharpSense™ upgrade significantly reduced the total number of detected episodes by 92% (pause: 93%, brady: 87%) and the rate of transmitted episodes by 73.6% from 50.3 to 13.3 (pause: 34.9 to 6.0, brady: 7.8 to 1.5) episodes per patient-week (p < 0.001). SharpSense™ reduced false positive episodes by 82.8% and 91.5% for pause and brady, respectively. The percentage of devices with at least one false positive episode was reduced from 52% to 35% for pause and from 39% for 20% for brady. The number of devices with false positive rate greater than 1 episode per week was reduced from 39% to 20% for pause and from 23% to 8% for brady. Conclusion: SharpSense™ upgrade resulted in substantial reduction of pause and bradycardia episode detections, false positive detections, and frequency of transmitted episodes for clinic review.

Download Full-text