Utility Of Implantable Loop Recorder Research Articles

Real-world utility of implantable loop recorders

Abstract Background Implantable loop recorders (ILRs) allow prolonged and continuous single-lead electrocardiogram recording and have significantly shortened time to electrocardiographic diagnosis and appropriate therapy of many bradyarrhythmias and tachyarrhythmias. Purpose The aim of this retrospective single center study was to evaluate ILR indications, diagnostic yield and ILR-guided interventions. Methods We retrospectively analyzed 388 patients (223 male / 165 female), who underwent Medtronic and Biotronik ILRs implantation at a heart center. Demographic and clinical data were obtained from the medical records. Remote monitoring was analyzed when no data of in-hospital follow up could be acquired. Results The mean age at ILR implantation was 63.4 ± 14.9 years with a mean follow-up of 20.7±17.6 months from ILR implantation. In total, 152 (39.2%) patients were followed by a remote monitoring system. Number of patients with ILR indication due to syncope (n=171; 44.1%) was significantly higher compared to patients with monitoring after ablation of atrial fibrillation or atrial flutter (n=108; 27.8%), cryptogenic stroke (n=50; 12.9%) and presyncope and dizziness (n=21; 5.4%) (p<0.05). After 12 months, arrhythmia was detected in 198 cases (79.2% out of 250 patients with detected arrhythmias). The most common type of arrhythmia was paroxysmal atrial fibrillation (31.7%) with a significantly higher prevalence compared to atrial tachycardias (16.5%) and supraventricular premature beats (9.8%) (p<0.05). Noteworthy, in 132 (52.8% out of 250) patients, ILR diagnosis corresponded to the suspected arrhythmia, whereas in 118 patients unexpected arrhythmias were detected. ILR diagnosis of arrhythmia lead in 147 (58.8%) patients to initiation of a new therapy or to a change of current medication. Changes of current medication occurred in 72 patients (28.8%), electrophysiology study/ablation in 66 patients (26.4%), pacemaker/ICD implantation in 46 (18.4%), electrical cardioversion in 6 patients (2.4%), and closure of the left atrial appendage in 1 patient. Conclusion Our study shows, that ILRs are an important diagnostic tool, providing clinical relevant data in about two thirds (65%) of the patients. About half (52.8%) of the detected arrhythmia correlated with the symptoms leading to ILR implantation (number needed to treat was around 2). Remote monitoring improves the diagnostic timing with a potential reduction of costs for health care. However, patient selection is critical and ILRs benefits needs to be proven in larger randomized trials.

Abstract 1122‐000226: Collaborative Stroke Pathway for In‐Patient Implantation of Long‐Term Cardiac Rhythm Monitors for Atrial Fibrillation Detection

Introduction : Atrial fibrillation (AF) is a recognized risk factor of ischemic stroke and AF‐related stroke is twice more likely to prove fatal. Long‐term cardiac rhythm monitoring has greater diagnostic yield compared to conventional monitoring in detecting AF. Utility of implantable loop recorder (ILR) in detecting AF was established not only in patients with cryptogenic stroke but more recently in strokes due large artery atherosclerosis and small vessel disease Stroke AF trial. We present a collaborative care pathway and share multi‐year data on ILR implantation. Methods : A review of prospectively collected registry of ILR implantations performed at a Comprehensive stroke center was conducted. Data from 2017–2019 of in‐patient and out‐patient implantation was analyzed. Eligible patients identified by vascular neurology (VN) underwent in‐patient implantation primarily by interventional neurology (IN) and as out‐patient by electrophysiology Cardiology. In‐patient implant and programming were done on the day of discharge. Continuous monitoring was followed by EP Cardiology. AF detection was urgently communicated by EP Cardiology and anticoagulation initiated by VN. Patients lost to follow up or lacking information in medical records were excluded from analysis. Results : Total of 428 ILR implantations were performed over a period of 3 years (1/2017 ‐ 12/2019) with majority implants as in‐patient prior to discharge 290 (67.8%) and out‐patient 78 (32.2%). Inpatient ILR placement was noted to be 75% in 2017, 78% in 2018 and 80% in 2019. 57.2% of in‐patient ILRs were placed by IN and 42.8% by EP. Average time to in‐patient ILR was 4.1 days with 77% within 5, 18.5% within 10, and <5% within 11 or more days post‐stroke. Average time to out‐patient ILR placement was 57 days with only 16% within 15, 29% within 30 day and 53% in more than 30 days from stroke. Over the course of 2 years of monitoring, AFib was detected in 33% with false detection in 1.5% (19.6% in 2017, 26% in 2018 and 36.5% in 2019). Conclusions : A multispecialty collaborative care pathway to increase implantation rate in eligible patients is recommended. In‐patient implantation allows establishing continuity of care, patient retention, prevents lost to follow‐up, avoids delay in monitoring, and importantly decreases the risk of stroke recurrence by early initiation of anticoagulation.

Implantable Loop Recorders-Syncope, Cryptogenic Stroke, Atrial Fibrillation.

The implantable loop recorder (ILR) is a subcutaneous, single-lead, electrocardiographic (ECG) monitoring device used for diagnosis in patients with recurrent, unexplained episodes of palpitations or syncope, for long-term monitoring in patients at risk for atrial fibrillation (AF), and to guide clinical management in patients with known AF. These devices are capable of storing and transmitting ECG data automatically in response to a significant bradyarrhythmia or tachyarrhythmia or in response to patient activation. This document aims to review the clinical utility of ILRs for arrhythmia monitoring in common clinical situations such as syncope, cryptogenic stroke, and management of patients with known AF.

The diagnostic yield of implantable loop recorders stratified by indication: "real-world" use in a large academic hospital.

To report on the clinical utility of implantable loop recorders (ILRs) in a large academic hospital setting over a 4-year period. Retrospective study (2013-2016) of patients receiving ILRs for any indication including syncope, cryptogenic stroke (CrS), atrial fibrillation (AF) burden, palpitations, ventricular arrhythmias (VA), and other. Remote checks, symptomatic transmissions, and in-person checks were reviewed. Time to diagnosis was documented. A total of 263 patients (54% male, mean age 63 ± 15years, mean follow-up 601 (range 9-1714) days) received ILRs for 324 indications; multiple indications were noted in 53/263 (20.2%) patients. ILR indications were 126 (39%) syncope, 81 (25%) CrS, 46 (14%) AF, 37 (11%) palpitations, 10 (3%) VA, and 24 (7%) other. Diagnostic yield for each indication was compared to the overall yield for all other indications. Three indications showed a significantly higher yield: AF (65% vs. 22%, p<0.002), palpitations (60% vs. 24%, p<0.001), and VA (70% vs. 28%, p<0.004). For all other indications, there were no significant differences. Syncope had nearly half the diagnostic yield of previously published trials (28% vs. 43-56%). We observed a fourfold increase in ILR implant rate over the study duration. In a "real-world" academic hospital setting, the diagnostic rate of ILRs was highest for AF, palpitations, and VA; however, these high yield indications comprised only 29% of all indications. The diagnostic yield for the commonest indication (syncope) was approximately half that reported in the previously published trials. With increasing implantation rates, additional studies are required to refine guideline-based indications for ILR implantation to improve diagnostic yield.

Implantable rhythm devices in the management of vasovagal syncope.

The ECG registration during syncope allows physicians either to confirm or exclude an arrhythmia as the mechanism of syncope. Implantable loop recorders have an over-writeable memory buffer that continuously records and deletes the patient's ECG for up to three years. Many studies have analyzed the utility of implantable loop recorders in recurrent unexplained or high risk syncope. These studies suggest that early use of the ILR provides more and earlier diagnoses and could help in selecting patients with vasovagal syncope and prolonged asystolic pauses who might benefit from pacemaker therapy. However many questions remain, including its performance in the community by physicians with a range of experience in diagnosing syncope. Furthermore there is no evidence that the use of the ILR changes outcome. Numerous attempts have been made to determine whether patients with predominantly cardioinhibitory syncope benefit from permanent pacemakers, especially if symptoms are frequent and debilitating. While the first open label trials of pacemakers in the treatment of vasovagal syncope showed promising results, this effect has not been confirmed by blinded randomized clinical trials. More recent data seem to suggest that patients over 40years with severe asystolic vasovagal syncope might benefit from permanent pacemakers.

Utility of implantable loop recorders for diagnosing unexplained syncope in clinical practice.

Establishing a symptom-rhythm correlation in patients with unexplained syncope is complicated because of its sporadic, infrequent, and unpredictable nature. Prolonged monitoring with an implantable loop recorder (ILR) allows the recording of electrocardiogram (ECG) data from a spontaneous syncopal event. The aim of this study was to evaluate the usefulness of the ILR for the diagnosis of syncope of unknown origin after conventional management in clinical practice. We reviewed the results with ILR implantation in patients with syncope of unknown origin after conventional management in the cardiology department at HU Marques de Valdecilla (Santander, Cantabria, Spain). One hundred and forty patients (age 64 +/- 16 y; 86 male [62%]) with syncope of unknown etiology after conventional work-up underwent prolonged monitoring with an ILR from September 1998 to February 2006; 46 patients (33%) had structural heart disease. During a mean follow-up of 346 +/- 160 d, 51 patients (36.5%) had recurrent syncope with diagnostic ECG recording. An arrhythmic cause for syncope was found in 33 of them (64.5%), with bradycardia present in 27 (53%) and tachycardia in 6 (11%). There were no sudden deaths, and 1 patient suffered a complication related to a recurrence of syncope. Long-time experience with the ILR confirmed the utility of this device in the diagnosis of unexplained syncope in clinical practice. Most of these patients had syncope of arrhythmogenic etiology that could be successfully treated. This strategy of prolonged monitoring is safe even in patients with structural heart disease.

Utility of Implantable Loop Recorder in Patients with Syncope—Results of Unexplained Syncope Trial (RUST)

Background: Syncope represents a common problem in cardiology practice. The use of implantable loop recorders (ILR) to provide long-term monitoring may assist in the diagnosis of unexplained syncope.

Syncope

Syncope

The utility of implantable loop recorders for diagnosing unexplained syncope in 100 consecutive patients - 5 year single center experience

The utility of implantable loop recorders for diagnosing unexplained syncope in 100 consecutive patients - 5 year single center experience

Utility of implantable loop recorder (Reveal Plus) in the diagnosis of unexplained syncope

In about 30% of patients with syncope, the responsible mechanisms remain unrecognised. Nevertheless, the possibility of an arrhythmic aetiology remains, however, difficult to rule out. We therefore monitored with an implantable loop recorder (ILR, Reveal Plus, Medtronic) 34 subjects (60+/-15 years) with at least two unexplained syncopal episodes and negative neurological and cardiovascular work-up. During a follow-up of 7+/-4 months, syncope occurred in 11 subjects. In nine of them the mechanisms responsible for these events were identified by ILR monitoring: marked bradycardia or asystole (n=6), atrial fibrillation with wide QRS tachycardia (n=1) and sinus rhythm with fine artifacts likely to be due to muscle contractions (n=2). Pre-syncope occurred in seven patients: advanced atrioventricular block (n=3), sinus tachycardia (n=1), and wide QRS tachycardia (n=1) were documented. Thus, when considering all 18 patients with recurrences, a diagnosis was achieved in 53% of subjects. Recognition of the rhythm disorder in seven patients with syncope and four patients with pre-syncope guided patient management. These data indicate that ILR monitoring facilitates the identification of mechanisms responsible for recurrences and therapeutic management in subjects with syncope or pre-syncope and negative traditional neurological and cardiovascular work-up.