Pleural cavity migration of an implantable loop recorder

Background/AimsThe reimbursement policy for cryptogenic stroke (CS) was expanded in November 2018 from recurrent strokes to the first stroke episode. No reports have demonstrated whether this policy change has affected trends in implantable loop recorder (ILR) utilization.MethodsWe identified patients who received an ILR implant using the Korea Health Insurance Review and Assessment Service database between July 2016 and October 2021. Patients meeting all the following criteria were considered to have CS indication: 1) prior stroke history, 2) no previous history of atrial fibrillation or flutter (AF/AFL), and 3) no maintenance of oral anticoagulant for ≥4 weeks within a year before ILR implant. AF/AFL diagnosed within 3 years after ILR implant or before ILR removal was considered ILR-driven.ResultsAmong 3,056 patients, 1,001 (32.8%) had CS indications. The total ILR implant number gradually increased for both CS and non-CS indications and the number of CS indication significantly increased after implementing the expanded reimbursement policy. The detection rate for AF/AFL was 26.3% in CS patients over 3 years, which was significantly higher in patients implanted with an ILR within 2 months after stroke than those implanted later.ConclusionsThe expanded coverage policy for CS had a significant impact on the number of ILR implantation for CS indication. The diagnostic yield of ILR for AF/AFL detection seems better when ILR is implanted within 2 months than later. Further investigation is needed to demonstrate other clinical benefits and the optimal ILR implantation timing.

Introduction: Patients who suffer from cryptogenic stroke (CS) are routinely screened for asymptomatic paroxysmal atrial fibrillation (AF) with implantable loop recorders (ILRs). The clinical risk factors associated with AF after CS are not fully defined, and it is a common perception that ILRs are not helpful in younger patients with CS. Research Questions/Objectives: To identify which clinical characteristics are associated with AF detection via ILR in patients who have suffered CS. To identify if there is an age cut-off, below which ILR implantation is likely to be futile in patients with CS. Methods: A retrospective cohort study was conducted on patients with CS who underwent ILR implantation at Thomas Jefferson University Hospital from 04/2019 to 04/2021. Patients were excluded from the analysis if there was <6 months of ILR follow-up, delayed ILR placement (>1 year after CS), or pre-existing (known) AF. Baseline demographics and clinical characteristics were collected (Table 1). Patients with and without AF detection within 1 year of CS were compared and multivariable logistic regression was applied to the univariate predictors that were significant (Table 2). Analyses were run in R Studio 4.4.2. Results: We identified a total of 282 patients with CS who received ILRs. Of these 282 patients, 218 formed the study group after applying exclusion criteria (age 63.45±10.58 years, 45% female). AF was detected within 1 year of CS in 47 patients (21.6%) with a mean time from CS to AF detection of 125.30± 94.64 days. In univariate analyses, AF was statistically significantly associated with older age, LAVI, CHA2DS2-VASc score, LVEF%, CKD stage, and presence of atrial runs (Table 1). After multivariable adjustment (Table 2), CKD stage 5 (OR 14.4, p=0.0168), atrial runs (OR 3.77, p=0.0079), and age (OR 1.11, p=0.0056) remained significantly associated with AF detection. However, there were 5 patients below the age of 60 who had AF detected. No significant differences were observed in sex, race, BMI, or other comorbidities. Conclusions: Stage 5 CKD, atrial runs, and age showed significant association with AF detection after cryptogenic stroke. Although age was statistically significant, the OR was low (1.11), and 5 patients below the age of 60 had AF detected. Renal failure and atrial runs were the strongest associates of AF detection after CS. We conclude that there should be no minimum age cut-off for ILR implantation in CS patients.

Background Cryptogenic stroke represents about 25–30% of all ischemic strokes. Continuous electrocardiographic monitoring using implantable loop recorder (ILR) can detect asymptomatic and undiagnosed atrial fibrillation (AF). Purpose To assess patient-specific factors in ILR implantation and AF detection in patients with cryptogenic strokes. Methods We retrospectively reviewed 379 patients with cryptogenic stroke indicated for ILR implantation, from January 2017 to June 2021 at our university hospital. We evaluated patient demographic and clinical characteristics to assess the risk factors associated with higher incidence of AF detection, using logistic regression models. Results Of the 379 ILRs implanted, 60.4% were males with 71.2% Caucasian, mean age 67.6 years, and mean BMI 28.5. The mean CHADSVASC score of 3.9 at the time of ischemic stroke. These patients had prior diagnosis of diabetes mellitus (27.4%), hypertension (65.7%), chronic kidney disease (19.5%), coronary artery disease (20%) and congestive heart failure (2%). Of the entire cohort, AF was diagnosed in 16% of patients with 14 months mean follow up. There were more females diagnosed with AF on ILR (20% v. 18.7%, p>0.05). Caucasians were more likely to have AF detected compared to non-Caucasians (OR 2.3, 95% CI, p<0.02). There were 52 patients with mobile cardiac outpatient telemetry (MCOT) before having ILR implantation. AF was not detected on MCOT, but 15% were diagnosed with AF with ILR monitoring. In univariate analysis, increasing age is strongly associated with the detection of AF (p=0.03). Conclusions There continues to exist race disparities in ILR implantation and eventual AF detection, leading to further socioeconomic health disparities. ILR should be considered especially in elderly with cryptogenic stroke given the higher incidence of AF detection. Funding Acknowledgement Type of funding sources: None.

Funding AcknowledgementsType of funding sources: None.IntroductionBesides the established class I indication for the evaluation of patients with recurrent syncope of uncertain origin, implantable loop recorders (ILRs) have been increasingly used for other diagnostic purposes (e.g. detection of atrial fibrillation (AF) following cryptogenic stroke).PurposeTo describe the main indications to ILR and to investigate procedural parameters, outcomes and diagnostic yield of ILR in a single, high-volume tertiary care centre.MethodsAll patients undergoing ILR implantation between November 2007 and April 2022 were consecutively enrolled in this study. Clinical characteristics of patients, procedural data and outcomes were collected. The indications to ILR implantation were divided into four categories: 1) AF detection in patients with recent cryptogenic stroke or peripheral thromboembolism [CRYSP], 2) recurrent syncope of uncertain origin [RSUO], 3) monitoring of ventricular arrhythmic events [VAE] in patients with predisposing cardiomyopathy/channelopathy, 4) monitoring of AF burden or relapse [AFB]. The main endpoint of the study was the diagnostic yield (number of definitive diagnoses made) and the time to diagnosis following ILR implantation. The occurrence of acute or subacute complications was used as a secondary safety endpoint.ResultsOverall, 1442 patients underwent ILR implantation (mean age 65 years, 43% female). The two main indications to ILR were AF detection following CRYSP and RSUO (42% and 34% of all implantations respectively, table 1). The commonest site of implantation was the left parasternal position (902 patients, 63%), median procedural time was 20 minutes (IQR 15-25). During a median follow-up of 397 days (134-1094), infections requiring ILR extraction or pocket revision occurred in 13 patients (0.9%). A definitive diagnosis was achieved in 500 (35%) patients after a median time of 206 days (IQR 60-533) [table 1 shows details and action taken following diagnosis for each indication subgroup]. At multivariable analysis, age and PR interval duration were significantly associated with the need for PM/ICD implantation among patients receiving ILR for RSUO whilst age was associated with AF detection among those with CRYSP (table 2).ConclusionsIn this cohort of patients use of ILR was associated with a good diagnostic yield regardless of the initial indication, triggered timely therapeutic actions and was overall safe.Table 1Table 2

Introduction Besides the established class I indication for the evaluation of patients with recurrent syncope of uncertain origin, implantable loop recorders (ILRs) have been increasingly used for other diagnostic purposes (e.g. detection of atrial fibrillation (AF) following cryptogenic stroke). Purpose To describe the main indications to ILR and to investigate procedural parameters, outcomes and diagnostic yield of ILR in a single, high-volume tertiary care centre. Methods All patients undergoing ILR implantation between October 2010 and October 2019 were consecutively enrolled in this study. Clinical characteristics of patients, procedural data and outcomes were collected. The indications to ILR implantation were divided into four categories: 1) AF detection in patients with recent cryptogenic stroke or peripheral thromboembolism [CRYSP], 2) recurrent syncope of uncertain origin [RSUO], 3) monitoring of ventricular arrhythmic events [VAE] in patients with predisposing cardiomyopathy/channelopathy, 4) monitoring of AF burden [AFB]. The main endpoint of the study was the diagnostic yield (number of definitive diagnoses made) and the time to diagnosis following ILR implantation. The occurrence of acute or subacute complications was used as a secondary safety endpoint. Results Overall, 1008 patients underwent ILR implantation (mean age 64 years, 43% female). The two main indications to ILR were AF detection following CRYSP and RSUO (41% and 34% of all implantations respectively, table 1). The commonest site of implantation was the left parasternal position (570 patients, 57%), median procedural time was 20 minutes (IQR 15–25). During a median follow-up of 580 days (186–1179), a definitive diagnosis was achieved in 366 (36%) patients after a median time of 208 days (IQR 59–515) [table 1 shows details and action taken following diagnosis for each indication subgroup]. Infections requiring ILR extraction or pocket revision occurred in 12 patients (1.2%). Conclusions In this cohort of patients use of ILR was associated with a good diagnostic yield regardless of the initial indication, triggered timely therapeutic actions and was overall safe. Funding Acknowledgement Type of funding source: None

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.

Implantable loop recorders (ILR) are used to screen for atrial fibrillation (AF) in patients with cryptogenic stroke (CS). However, there is limited real-world data regarding the long-term rate of AF detection using ILR and management consequences in patients with CS. The objective is to assess the rate of AF detection in patients with CS in a real-world study over 36 months of follow-up and its consequences on stroke prevention. This retrospective study included patients with an ILR placed for CS at Baylor College of Medicine and Baylor St. Luke's Medical Center between January 2014 and July 2021. The primary outcome was AF detection in patients with ILR. The secondary outcome was the rate of subsequent strokes after ILR placement in patients with or without diagnosed AF. The AF detection rate in our cohort was compared to the rate in CRYSTAL-AF Trial at 36-month follow-up. The impact of AF detection on clinical management was examined. We identified 225 patients. 51.1% were women and 38.2% African American. Among 85 patients with ILR labeled AF, 43 patients had true AF, and 42 had incorrectly labeled AF (48.3% false positive). The estimated AF detection rate at 36 months follow-up was 28.6% (95% CI, 26.6%-30.6%). 58.1% of patients with AF were initiated on oral anticoagulation, 80.0% of whom were started on a direct oral anticoagulant. 13.8% of patients had recurrent strokes after ILR implantation; 4 of whom were diagnosed with AF. Compared to CRYSTAL-AF, the AF detection rate in our cohort is similar, but this cohort includes a higher proportion of female and African American patients. Most patients with recurrent strokes after ILR implant did not have AF during 36 months of monitoring.

Meta-Analysis of Randomized Clinical Trials Comparing the Impact of Implantable Loop Recorder Versus Usual Care After Ischemic Stroke for Detection of Atrial Fibrillation and Stroke Risk

Atrial fibrillation (AF) is responsible for 15-20% of ischemic strokes. AF can be asymptomatic and remain undetected following acute stroke, initially classifying the event as cryptogenic. Implantable loop recorders (ILRs) provide long-term cardiac monitoring and are superior to traditional methods for detecting AF in patients with cryptogenic stroke. ILR placement is often performed by a cardiologist in an outpatient setting. Our institution identified that some patients were missing or cancelling appointments for device implantation. Failure to detect AF is associated with a greater risk of stroke recurrence. An interdisciplinary inpatient process was developed to place ILRs at the bedside on the stroke unit, prior to discharge. The purpose of the program was to increase patient compliance with ILRs, improve detection of asymptomatic AF, and reduce incidence of stroke recurrence through timely initiation of oral anticoagulants. To evaluate the program and provide recommendations, measures of success included rates of patient compliance with ILR implantation using inpatient vs. outpatient procedure and the percentage of patients who received a diagnosis of AF after ILR placement. Using 18 months of pre-implementation data as a benchmark, the average implant rate increased in the first 12 months following implementation. Of 97 patients who received ILR placement, nine (9%) have received a diagnosis of AF. Since three-year ILR monitoring has shown significantly higher AF detection than 30-day cardiac monitoring after cryptogenic stroke, more patients with AF may yet be identified. This presentation will demonstrate an increase in ILR implant rates and AF detection and highlight positive results using advanced practice professionals to perform the procedure. The program produced financial benefit and mitigated access to care barriers, with no poor outcomes or compromise in quality, and no negative impact on inpatient length of stay. In conclusion, bedside insertion of ILRs prior to discharge after cryptogenic stroke is a safe, efficient, cost-effective process that increases patient compliance when compared to outpatient return visits, improving detection of AF and prompt initiation of oral anticoagulants, and may reduce stroke recurrence.

Background: Implantable Loop Recorders (ILR) are increasingly being used for detection of atrial fibrillation (AF) after cryptogenic stroke (CS). There is limited data on determinants of diagnostic yield in this population. Objective: To systematically review prior available trials studying ILRs in CS to look for predictors of diagnostic yield of ILR over time. Methods: We searched MEDLINE and Cochrane Central Register of Controlled Trials. We included studies of ILRs on patients who presented with acute CS. We excluded studies which did not analyze baseline characteristics of patients with and without AF detection. Results: Our search revealed six prospective studies which met inclusion criteria with a total of 344 patients. All patients had at least 24 hour ambulatory EKG prior to ILR implantation. The mean duration of ILR monitoring was 445.2 days. On an average 24.4% of patients had new AF detected with an average time to detection of 85.5 days. Table 1 shows summary statistics and meta-analysis combinations of studies. Comparing covariates among patients with and without AF detection, a basic combination of individual study p-values (Z score) revealed age, CHADS-Vasc score, left atrial (LA) volume and ectopy to be significantly different in the two groups. Analyzing significance with χ 2 combination methods and combinations of effect size values suggested only CHADS-Vasc score to be significant. Ectopy was presented in terms of burden of APCs in two studies which showed significant difference between groups; and in terms of proportions of cases with “excessive” atrial ectopy in two other studies which did not show significance. Conclusions: Overall AF was detected in 24.4% of patients with ILR implantation after CS. CHADS-Vasc score was found to be a significant predictor in detecting AF. Older age, increased LA volumes and excessive ectopy on holter were found to be significant in some studies but on overall computation did not show statistical significance.

Safety and outcome of nurse-led syncope clinics and implantable loop recorder implants

Background There is limited published data on the use of implantable loop recorders (ILRs) in patients with long QT syndrome (LQTS). Purpose We sought to evaluate the utility of the ILR in patients who had a diagnosis of LQTS or who had a family history of LQTS. Methods We carried out a retrospective analysis of patients attending an Inherited Cardiac Conditions Clinic who had an active ILR and who had a diagnosis or family history of LQTS. Patient demographics, indications for ILR implantation and clinical outcomes were compiled. Results Nine patients with a diagnosis of LQTS and an active ILR were identified with an average age of 37 years. Genetic results were available for seven patients. Four patients had a confirmed pathogenic mutation (one KCNQ1 and three KCNH2), one patient had a variant of uncertain significance in SCN5A and two patients had negative genetic testing. Indications for implantation were syncope (n=4), recurrent altered consciousness episodes (n=1), assessment of occult arrhythmia or beta blocker complications (n=2), palpitations and dizziness (n=1) and nocturnal dyspnoea and palpitations (n=1). Mean follow-up was 706 days and average age at ILR implant was 35 years. The ILR for three patients was a second device, implanted after end of battery life of the initial ILR. ILR recordings led to a change in management in three patients: finding of paroxysmal atrial fibrillation (n=1), finding of nocturnal QTc of 511ms with a change in medications (n=1) and a pause leading to cessation of beta blocker (n=1). Eleven patients with a family history of LQTS and active ILR were identified. Nine patients were female, and the average age was 44.4 years. Genetic test results were available for five patients. Three patients had a pathogenic mutation in SCN5A, and two patients had negative genetic testing for common LQTS genes. Indications for implantation included syncope (n=5), lightheaded episodes (n=3) and risk assessment in gene carriers (n=3). The mean duration of ILR follow-up was 680 days and average age at ILR implant was 42.5 years. Five patients had no arrhythmia detected during ILR recording, two patients had supraventricular tachycardia identified, in two patients ILR data outruled a sinister cause for a symptomatic episode, one patient had documentation of SVT and brief NSVT which led to referral for electrophysiology study and one patient had no recurrence of symptoms and a second ILR was implanted. Conclusion ILRs were inserted in selected patients with a diagnosis of LQTS or in patients with a family history of LQTS or who were gene carriers. Rationale for ILR implantation included risk stratification, monitoring for occult arrhythmia and rhythm-symptom correlation in symptomatic patients. The ILR impacted management in almost 50% of patients and is considered an important tool in selected patients attending Inherited Cardiac Condition Clinics. Funding Acknowledgement Type of funding sources: None. Table 1

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.

IntroductionBritish Heart Rhythm Society has published standards for the insertion, follow up and explant of implantable loop recorders (ILRs). Although an increasing number of UK centres have developed services for...

The migration of an implantable loop recorder (ILR) is a rare complication. We aimed to perform a meta-summary of case reports to characterize patients who experienced an ILR migration. We searched for case reports published in PubMed, Google Scholar, Scopus, and Embase from January 2017 to 2023 using the following keywords: "migration ILR," "migration loop recorder," "complication loop recorder," and "complication ILR." Seven case reports/case series reporting ILR migration were included. Data about patients' characteristics, ILR implantation, time of onset, management, and clinical outcome of this complication were collected. Seven patients who experienced the migration of an ILR were examined. All patients experienced migration within 35 days following ILR implantation. The clinical suspicion of ILR migration mainly arose from patients' symptomatology. The migration of the ILR was confirmed by a radiological scan in all cases, and surgical removal, preferably by video-assisted thoracic surgery, was required. In conclusion, intrapleural migration is a rare complication of ILR implantation. It may occur in the early postprocedural period. Clinical suspicion arises from symptoms, but a radiological scan is necessary to confirm the diagnosis. Surgical removal is mandatory.