Implantable Loop Recorders—Syncope, Cryptogenic Stroke, Atrial Fibrillation

Introduction: Cryptogenic strokes account for up to 40% of ischemic strokes. Atrial fibrillation (AF) is a known cause of ischemic stroke. Current data shows that occult AF can be detected by implantable devices at higher rates than conventional cardiac rhythm monitoring. There are, however, limited data available on risk factors and outcomes associated with AF detection by implantable loop recorders (ILRs). Objective: To investigate the risk factors and outcomes associated with occult AF detected by ILR in patients with cryptogenic stroke. Methods: We conducted a retrospective chart review of patients admitted with cryptogenic stroke at Ascension St John Hospital and Ascension Macomb-Oakland Hospital in Michigan who had ILRs placed from 1/1/2016 to 1/31/2020. Data were collected on demographics, comorbidities, treatment and outcomes. AF detection was defined as continuous AF for 30 seconds. Data were analyzed using Student’s t-test, the χ2 test and logistic regression. Results: We reviewed 172 patients, 52.3% male, 56.4% white, mean age 62.7 ± 13.6 years. The incidence of AF detection by ILR was 14% (24/172) over a mean follow-up of 12.75 ± 10.71 months. The mean duration of monitoring prior to AF detection was 4.5 months (range:1 day to 14 months). The median duration of AF was 6 minutes (range: 37.2 seconds to 11.3 hours). From univariable analysis, older age (p=0.03), male sex (p=0.09), embolic stroke pattern on imaging (p=0.06), and lack of AF symptoms (p=0.001) were associated with AF detection by ILR. From multivariable analysis, patients with detected AF were more likely to be older (OR=1.04, p=0.04), male (OR=3.6, p=0.03), asymptomatic (OR=6.3, p=0.01), and have an embolic stroke pattern on imaging (OR=3.3, p=0.04). 95.7% of patients with confirmed AF were started on anticoagulation for secondary stroke prevention. There was no difference in the incidence of stroke post-hospitalization between those with AF detection and those without (16% vs. 16.4%, p=0.96). Conclusions: In patients with cryptogenic stroke, age, gender, stroke pattern, and lack of AF symptoms are independent predictors of occult AF detection by ILR. Most patients with confirmed AF were started on anticoagulation for secondary stroke prevention and had low stroke recurrence rates.

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Implantable Loop Recorders for Cryptogenic Stroke (Plus Real-World Atrial Fibrillation Detection Rate with Implantable Loop Recorders)

Cardiac Electrophysiology Clinics ◽

10.1016/j.ccep.2017.11.011 ◽

2018 ◽

Vol 10 (1) ◽

pp. 111-118 ◽

Cited By ~ 3

Author(s):

Dan L. Musat ◽

Nicolle Milstein ◽

Suneet Mittal

Keyword(s):

Atrial Fibrillation ◽

Real World ◽

Detection Rate ◽

Cryptogenic Stroke ◽

Implantable Loop Recorders ◽

Atrial Fibrillation Detection

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Abstract 14083: Implantable Loop Recorders Change Management in Patients With Cryptogenic Stroke With or Without Atrial Fibrillation

Circulation ◽

10.1161/circ.142.suppl_3.14083 ◽

2020 ◽

Vol 142 (Suppl_3) ◽

Author(s):

Danni Fu ◽

Richard Jones ◽

Xing Dai ◽

Michael Wu ◽

Tina Burton

Keyword(s):

Atrial Fibrillation ◽

Rhode Island ◽

Clinical Management ◽

Cryptogenic Stroke ◽

Cardiac Risk ◽

Structural Features ◽

Battery Life ◽

Single Center Study ◽

Implantable Loop Recorders

Introduction: Implantable loop recorders (ILR) are widely used for long term arrhythmia monitoring in patients with cryptogenic stroke (CS). Single center study has shown that some patients with incidental arrhythmias found by ILR, aside from atrial fibrillation (AF), resulted in changes in clinical management. Unfortunately, a large portion of the patients had premature ILR explantation before the end of battery life and other studies on incidental arrhythmias are limited. Hypothesis: We sought to determine the rate of occurrence of incidental arrhythmias other than AF on ILR monitoring among patients with CS and to characterize the rate of these incidental arrhythmias that result in a change in clinical management. Methods: All adult patients with ILR for CS at Rhode Island Hospital between 1/2015-1/2019 were included. Demographics, cardiac risk factors and structural features, and ILR tracings were reviewed. Results: Three hundred and twelve patients were identified with a median follow up time of 27.9 months (IQR 18.5-35.8 months). Incidental arrhythmias were identified in 110 patients (35.2%) with a median of 7.8 months (IQR 4.4-16.2 months) at a rate of 20.1 per 100 person-years. AF was detected in 51 patients (16.3%) with a median of 3.9 months (IQR 1.3-12.3 months). Eighteen patients had both AF and incidental arrhythmias and incidental arrhythmias were found after AF in 8 of those patients. Premature explantation occurred in 9.3% of patients with the most common reason being patient preference. Twelve patients with incidental arrhythmias (10.9%) had a resultant change in management; 9 with procedural interventions and 3 with medication adjustments. Overall, the rate of actionable incidental arrhythmias is 2.2 per 100 person-years. Conclusions: Other than AF detection, long term EKG monitoring in patients with CS with ILR allows for detection of other arrhythmias. These incidental findings can result in changes in management and potentially favorable clinical outcomes.

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Investigating the Occult

10.1093/med/9780190495541.003.0016 ◽

2016 ◽

Author(s):

Ji Y. Chong ◽

Michael P. Lerario

Keyword(s):

Atrial Fibrillation ◽

Cryptogenic Stroke ◽

Cardiac Monitoring ◽

Stroke Patients ◽

Arrhythmia Detection ◽

Implantable Loop Recorders

Occult atrial fibrillation is more common than previously thought in patients with cryptogenic stroke, particularly in older cohorts. If stroke patients are suspected to have atrial fibrillation, intensive cardiac monitoring using implantable loop recorders or prolonged external monitors should be ordered and can result in higher rates of arrhythmia detection.

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