Implantable Loop Recorder In Patients Research Articles

Implantable loop recorders in patients with Brugada syndrome: the importance of a correct patient stratification.

Implantable loop recorders in patients with Brugada syndrome: the importance of a correct patient stratification.

The Role of Implantable Loop Recorder in Patients with Cryptogenic Stroke: A Systematic Review and Meta-analysis

The Role of Implantable Loop Recorder in Patients with Cryptogenic Stroke: A Systematic Review and Meta-analysis

Impact of an expanded reimbursement policy on utilization of implantable loop recorders in patients with cryptogenic stroke in Korea.

The 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. We 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. Among 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. The 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.

Diagnostic Yield and Clinical Implications of Implantable Loop Recorders in Patients with Syncope in Germany: A National Database Analysis.

In patients with unexplained syncope, implantable loop recorders (ILR) are used to detect arrhythmias as a cause of syncope. This study aimed to assess the diagnostic yield and clinical implications arising from ILR implantation in patients with syncope in Germany. Secondary longitudinal data were obtained from a large German research database including anonymized data from nationwide statutory health insurances, representative for the German population. Patients ≥ 18 years with a diagnosis of syncope and ILR implantation between 2017 and 2018 were analyzed, and cardiac diagnoses and therapies during a follow-up period of two years assessed. Of 2,403,301 continuously insured persons in 2017-2018, 1360 (0.1%) received an ILR and 675 patients (45.6% female) were included. During follow-up, arrhythmias were diagnosed in 65.0%. The following antiarrhythmic therapies were established: pacemaker and defibrillator implantations in 20% and 1.5%, respectively, ablation therapy in 3.0%, and antiarrhythmic drug therapy in 4.7%. Aside from the diagnoses typically associated with syncope, atrial fibrillation or flutter was diagnosed in 37.0%, and anticoagulation therapy was initiated in 21.5%. There was a high diagnostic yield of arrhythmias following ILR implantation, leading to a relevant number of syncope-specific treatment. Arrhythmias not necessarily related to syncope were also diagnosed, leading to a high rate of anticoagulation therapy.

Ultrasound-guided explantation technique for implantable loop recorder in patients with high body mass index: a practical approach

Ultrasound-guided explantation technique for implantable loop recorder in patients with high body mass index: a practical approach

Asystole on loop recorder in patients with unexplained syncope and negative tilt testing: age distribution and clinical predictors

BackgroundApproximately 50% of patients with unexplained syncope and negative head-up tilt test (HUTT) who have an electrocardiogram (ECG) documentation of spontaneous syncope during implantable loop recorder (ILR) show an asystolic pause at the time of the event.ObjectiveThe aim of the study was to evaluate the age distribution and clinical predictors of asystolic syncope detected by ILR in patients with unexplained syncope and negative HUTT.MethodsThis research employed a retrospective, single-center study of consecutive patients. The ILR-documented spontaneous syncope was classified according to the International Study on Syncope of Uncertain Etiology (ISSUE) classification.ResultsAmong 113 patients (54.0 ± 19.6 years; 46% male), 49 had an ECG-documented recurrence of syncope during the observation period and 28 of these later (24.8%, corresponding to 57.1% of the patients with a diagnostic event) had a diagnosis of asystolic syncope at ILR: type 1A was present in 24 (85.7%), type 1B in 1 (3.6%), and type 1C in 3 (10.7%) patients. The age distribution of asystolic syncope was bimodal, with a peak at age < 19 years and a second peak at the age of 60–79 years. At Cox multivariable analysis, syncope without prodromes (OR 3.7; p = 0.0008) and use of beta blockers (OR 3.2; p = 0.002) were independently associated to ILR-detected asystole.ConclusionsIn patients with unexplained syncope and negative HUTT, the age distribution of asystolic syncope detected by ILR is bimodal, suggesting a different mechanism responsible for asystole in both younger and older patients. The absence of prodromes and the use of beta blockers are independent predictors of ILR-detected asystole.

Implantable loop recorder monitoring in inherited cardiomyopathies: yield of clinically relevant arrhythmias

Abstract Background Implantable loop recorders (ILRs) are a minimally invasive tool for the diagnosis of arrhythmias in patients with unexplained syncope or asymptomatic arrhythmias. Their use in patients with inherited arrhythmia syndromes has been recommended in the recent 2022 ESC Guidelines (1). However, the clinical utility of ILRs in patients with inherited cardiomyopathies remains unexplored. Purpose The purpose of this study was to evaluate the yield of ILR monitoring in detecting clinically relevant events in a single cohort of patients with inherited cardiomyopathies. Methods We prospectively collected demographic, clinical, and follow-up data from patients with inherited cardiomyopathies (Arrhythmogenic Cardiomyopathy, ACM; Hypertrophic Cardiomyopathy, HCM; Dilated Cardiomyopathy, DCM; Left Ventricular Non-Compaction, LVNC) who were implanted with an ILR and were followed with telemedicine. The primary endpoint was a clinically significant event recorded with the ILR that required an update to an implantable cardioverter defibrillator (ICD). Results The study cohort included 53 consecutive patients (55% males; mean age at ILR implantation 35±14 years) with inherited cardiomyopathies: 33/53 (62%) with ACM, 9/53 (17%) with HCM, 7/53 (13%) LVNC, 4/33 (8%) DCM. None of the patients implanted had previously experienced life-threatening arrhythmias. During a median follow-up of 2.6 years (IQR 1.4-3.7 years) after ILR implantation, clinically relevant arrhythmic events were documented in 9/53 (17%) of patients. Specifically, sustained or non-sustained ventricular tachycardia episodes were detected in 8 patients (5 with ACM, 2 with LVNC, 1 with LMNA-related DCM), whereas one patient with HCM showed symptomatic pauses &amp;gt; 3 seconds due to sick sinus syndrome. In all cases, the detection of such episodes led to the upgrade to ICD implantation. Conclusions ILR monitoring of patients with inherited cardiomyopathies identified clinically relevant events in almost one-fifth of patients, suggesting that the use of ILR may substantially improve the management of these patients. Figure 1. Representative example of clinically actionable event detected by implantable loop recorder (ILR) in a patient with inherited cardiomyopathy. The patient, a 19-year-old male with a definitive diagnosis of Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) and a pathogenic PKP2 truncating variant, presented with palpitations and vertigo during physical exertion one year after the implantation of an ILR. ILR monitoring documented a rapid tachycardia with a mean frequency of 250 bpm lasting 3 minutes, prompting an indication for an implantable cardioverter defibrillator (ICD).Figure 1.

An unmet need: arrhythmia detection by implantable loop recorder in the systemic right ventricle.

Patients with systemic right ventricles are at high risk of sudden cardiac death. Arrhythmia is a significant risk factor. Routine Holter monitoring is opportunistic with poor adherence. The aim of this study was to determine if continuous rhythm monitoring with an implantable loop recorder (ILR) could allow early detection of clinically important arrhythmias. Implantable loop recorder implantation was offered to patients with atrial switch repair for transposition of the great arteries. Recordings were made with symptoms or, automatically for pauses, significant bradycardia or tachycardia and reviewed by the multi-disciplinary team. Twenty-four out of 36 eligible patients underwent ILR implantation with no complication. Forty-two per cent had preserved ventricular function, 75% were NYHA functional class I, 88% had low sudden cardiac death risk, 33% had previous intra-atrial re-entrant tachycardia (IART), and none had known conduction disease. Eighteen out of 24 (75%) patients made 52 recordings (52% automated) over 39.5 months (1.6-72.5). Thirty-two out of 52 (62%) recordings in 15/24 (63%) of the cohort were clinically significant and included sinus node disease (two patients), atrioventricular block (two patients), IART (seven patients), and IART with sinus node disease or atrioventricular block (four patients). Implantable loop recorder recordings prompted medication change in 11 patients [beta-blockers (n = 9), anti-coagulation (n = 5), and stopping anti-coagulation (n = 1)] and device therapy recommendation in seven patients [five pacemakers (three: atrioventricular block) and two defibrillators]. Two patients declined intervention; one suffered an arrhythmic death. Intra-atrial re-entrant tachycardia and clinically relevant conduction disease were detected in patients irrespective of sudden cardiac death risk. Continuous monitoring with an ILR in patients with systemic right ventricle following atrial switch detects clinically relevant arrhythmias that impact decision-making. In this cohort, clinically relevant arrhythmias did not correlate with sudden cardiac death risk.

Detection of atrial fibrillation using an implantable loop recorder in patients with previous cryptogenic stroke: the SPIDER-AF registry (Stroke Prevention by Increasing DEtection Rates of Atrial Fibrillation).

The use of implantable loop recorder (ILR) to detect atrial fibrillation (AF) in patients with a history of cryptogenic stroke (CS) has seldom been investigated in "real-world" settings. This study aimed to present the results of the Stroke Prevention by Increasing DEtection Rates of Atrial Fibrillation (SPIDER-AF) registry. SPIDER is a multicentric, observational registry, including 35 facilities all over Germany. It enrolled outpatients without AF history and with CS before ILR implantation. We included 500 patients (mean age 63.1 ± 12.7years), 304 (60.8%) were males, with previous stroke (72.6%) and TIA (27.4%). After inclusion, all were followed for at least 12months. AF was detected in 133(26.8%), 25.3% of patients with previous stroke and 29.9% with TIA (p = 0.30). AF was detected after a median of 121.5days (IQR 40.5-223.0). AF was primarily paroxysmal (95.7% after stroke, 100% after TIA). In 19.5% (n = 26) anticoagulation was not administered after AF detection. Mean CHA2DS2-VASc score (OR 1.22; CI 1.01-1.49; p = 0.037) and age > 70years (OR 0.41; CI 0.19-0.88; p = 0.0020) correlated with AF. Repeat cerebrovascular events at follow-up (28; 5.6%) correlated with AF (OR = 2.17; CI 1.00-4.72; p = 0.049). AF (p = 0.91) and recurrent events (p = 0.43) occurred similarly in females and males. In the context of cryptogenic strokes ILRs are a valuable tool for early detection of AF. In a real-world scenario, the anticoagulation therapy remains inadequate despite diagnosed AF in a relevant subset of patients requiring optimization of patient management.

The Role of Implantable Loop Recorder in Patients with Cryptogenic Stroke

Objective: The objective of this study was to provide data on implantable loop recorder (ILR)-based atrial fibrillation (AF) rates, recurrent stroke rates, and predictors of AF in patients with cryptogenic stroke (CS) after 1, 6, 12, 24, and 36 months of follow-up. Methods: We searched MEDLINE/PubMed, Cochrane Central Register of Controlled Trials, EMBASE, Web of Science, and reference lists of retrieved reports, which were published by April 30, 2023, which was the date of our last search. We utilized random-effects meta-analysis for detection rates, and meta-regression analysis, t-test (for normally distributed variables), and Mann-Whitney (for skewed variables) for predictor factors. Results: Thirteen studies were analyzed, which included data from 3,377 patients with CS or embolic stroke of undetermined source. The ILR-based AF rates in patients with CS were 4.73% (95% confidence interval [CI] 3.91–5.71) at 1 month, 13.45% (95% CI 12.19–14.81) at 6 months, 17.5% (95% CI 16.25–18.82) at 12 months, 20.69% (95% CI 19–22.49) at 24 months, and 25.98% (95% CI 23.21–28.58) at 36 months. Age and CHA2DS2-VASc score were positively associated with AF detection. Specifically, the mean difference of age and CHA2DS2-VASc score in the group with AF versus the group without AF was 7.47 (95% CI 4.58–10.36, P &lt; 0.001) and 0.75 (95% CI 0.22–1.28, P = 0.01), respectively. Finally, AF detection was positively associated with recurrent strokes with an estimated risk ratio of 1.27 (95% CI 0.69–2.31). Conclusions: There is a correlation between AF detection rate and ILR monitoring duration. One out of eight patients was diagnosed with AF after 6 months of follow-up and about one quarter after 3 years. Our results demonstrate the critical use of ILRs, especially in older patients, and in patients with high CHA2DS2-VASc scores.

492 EMBOLIC STROKE OF UNDETERMINED SOURCE: ROLE OF IMPLANTABLE LOOP RECORDER IN ASYMPTOMATIC ATRIAL FIBRILLATION DETECTION AND SECONDARY PREVENTION OF NEW EMBOLIC EVENTS

Abstract Background and Aims AF (Atrial Fibrillation) is the most important cause of Embolic Stroke of Undetermined Source (ESUS). Implantable Loop Recorder (ILR) demonstrated the highest sensitivity for detecting post-stroke asymptomatic AF. This register was created to assess the prevalence of AF episodes in patients after ESUS and to verify possible benefits on clinical outcomes such as TIA or stroke recurrence and death using ILR. Methods 278 patients admitted to the Stroke Unit of “Città della Salute e della Scienza” hospital in Torino between 2011 and 2019, underwent ILR implantation if they had at least one risk factor for AF including obesity, hyperthyroidism, atrial enlargement at transthoracic echocardiography, severe mitral valve disease, CHADS-VASc score ≥ 4, age &amp;gt; 70 years old and diabetes. The control group was composed of 165 patients admitted in other departments of the same hospital diagnosed with ESUS, not implanted with ILR. We used propensity score matching to select 132 patients from each group (matching age, sex, CHADS-VASc, and HAS-BLED baseline characteristics). Risk and protective factors were estimated for clinical outcomes (deaths and TIA or stroke recurrence) and were evaluated with logistic regression univariate and multivariate analyses. Results The detection rate of AF episodes longer than 5 minutes was significantly higher in the ILR group (41.7% vs 15.9%, p&amp;lt;0.001). On univariate analysis, we found a trend towards a protective role of ILR for the composite outcome of TIA or stroke recurrence and mortality (OR 0.52, CI 0.26–1.04, p 0.06). On multivariate analysis, we found a protective role of ILR in terms of deaths (OR 0.4, CI 0.17–0.94, p 0.03) and for the composite outcome of ischemic event recurrences and deaths (OR 0.41, CI 0.19–0.87, p 0.02). Age was consistently identified as a risk factor for all the clinical outcomes. Conclusion In patients with ESUS and at least one risk factor for AF, episodes of AF longer than 5 minutes are identified in 41.7% of the cases thanks to ILR. Our study demonstrated that a policy including ILR in patients with ESUS also gives a clinical benefit in terms of TIA or stroke recurrence and death, although limited size of the population and possible presence of selection bias may limit the generalisation of our results.

Diagnostic usefulness of implantable loop recorder in patients with unexplained syncope or palpitation

BackgroundIn a substantial proportion of patients with syncope, the exact cause is not identified because of the difficulty to document electrocardiograms correlated with the events during a syncope episode. Thus, an implantable loop recorder (ILR) was introduced for diagnosing hidden arrhythmia; however, its clinical use remains limited. Therefore, we conducted a retrospective analysis to assess the diagnostic value of the ILR in patients with unexplained syncope or palpitations.MethodsAll patients who had undergone ILR implantation from May 2016 to January 2020, were studied retrospectively. We analyzed their electrocardiogram stored in the device.ResultsAmong the 70 patients (mean age ± SD; 50.2 ± 20.3 years, 27 men) with unknown causes of syncope or palpitation, during two years follow-up, arrhythmia was detected in 26 patients (37.1%). Nineteen (73.1%) patients underwent permanent pacemaker implantation due to symptomatic bradycardia or atrioventricular block. All arrhythmias were detected within 6 days to 39 months after loop recorder implantation. Thirteen patients (50%) showed sick sinus syndrome (eight long pauses and five tachycardia-bradycardia syndromes). Eleven patients (42.3%) had paroxysmal atrioventricular block. Two patients who underwent permanent pacemaker implantation showed a positive tilt-table test. Three patients underwent radiofrequency catheter ablation for paroxysmal supraventricular tachycardia and atrial fibrillation. The mean duration for the detection of first sign (arrhythmia or palpitations) was 7.5 months, and the time from the detection of arrhythmia to ablation or device implantation was 3.4 months.ConclusionILR monitoring detected a substantial number of significant bradycardias in patients with unexplained syncope and palpitations, suggesting that it is an effective diagnostic method that can shorten the time required to identify the cause of arrhythmias.

Impact of Neuroimaging Patterns for the Detection of Atrial Fibrillation by Implantable Loop Recorders in Patients With Embolic Stroke of Undetermined Source.

ObjectivesAtrial fibrillation (AF) is a well-known etiology of embolic stroke of undetermined source (ESUS), although the optimal detection strategy of AF was not been fully evaluated yet. We assessed AF detection rate by implantable loop recorder (ILR) in patients with ESUS and compared the clinical characteristics and neuroimaging patterns between the patients with AF and AF-free patients.MethodsWe reviewed clinical characteristics and neuroimaging patterns of consecutive patients with who were admitted to our comprehensive stroke center for ESUS and underwent ILR insertion between August 1, 2019, and January 31, 202. The inclusion criteria were (1) 18 years of age or older; (2) classified as having cryptogenic stroke extracted from the group with undetermined stroke according to ESUS International Working Group; and (3) underwent ILR insertion during or after admission due to index ischemic events. Ischemic stroke pattern was classified as (1) tiny-scattered infarction, (2) whole-territorial infarction, (3) lobar infarction and (4) multiple-territorial infarction. Interrogations of data retrieved from the ILR were performed by cardiologists in every month after the implantation.ResultsIn this study, 41 ESUS patients who received an ILR implantation were enrolled (mean age, 64 years; male sex, 65.9%). The rate of AF detection at 6 months was 34% (14 patients), and the mean time from ILR insertion to AF detection was 52.5 days [interquartile range (IQR), 45.0–69.5]. The median initial NIH stroke scale scores were significantly greater in patients with AF than those without AF (6.5 vs. 3.0, p = 0.019). Whole-territorial infarction pattern was significantly more frequent in patients with AF than in those without AF (64.3% vs.11.1%, p = 0.002).ConclusionsHigher covert AF detection rates within the ESUS patients were most often associated with higher NIHSS and whole-territorial infarction patterns on brain imaging.

Is there clinical utility to replacement of an implantable loop recorder in patients who have previously undergone cryoballoon pulmonary vein isolation?

Abstract Funding Acknowledgements Type of funding sources: None. Background Implantable loop recorders (ILRs) are used for long-term ECG monitoring following catheter ablation in patients (pts) with atrial fibrillation (AF) to guide clinical management. However, little is known about what do when the ILR reaches end of service (EOS). Purpose To identify pts who underwent replacement of their ILR and determine the diagnostic yield and clinical utility of the replacement device. Methods We enrolled 222 consecutive pts with AF who underwent cryoballoon pulmonary vein isolation (CB PVI) and had an ILR. We identified pts who subsequently underwent ILR replacement. The diagnostic and clinical utility of the newly replaced ILR was determined. Results The cohort included 56 pts (64 + 9 years; 35 [63%] male; 27 [48%] PAF; CHA2DS2-VASc 2.3 ± 1.5) in whom the initial ILR reached EOS. They were followed for 3.7 ± 2.1 years. Recurrent AF was observed in 41 (73%) of these pts; this triggered an intervention in 17 (41%) pts (Figure). Of the other 15 (27%) pts without any documented AF, anticoagulation was withheld in 13 [87%] pts. Following ILR replacement, 33 (80%) of the 41 pts had more AF (n=11 [33%] required an intervention) and 5 additional pts had AF for the first time. Conclusions Our data show that after CB PVI, ILRs help guide decisions regarding rhythm management and oral anticoagulation. When the initial ILR was replaced by a second ILR, AF was detected (often for the first time) in some patients; the findings were used to guide clinical decision making in the entire cohort. Thus, at this time, it remains undefined when ECG monitoring of these pts can be stopped because it is no longer clinical meaningful.

The evidence for the implantable loop recorder in patients with inherited arrhythmia syndromes: a review of the literature.

Risk stratification of patients with inherited arrhythmia syndromes (IASs) can be challenging. Recent guidelines acknowledge a place for considering the implantable loop recorder (ILR) to outrule malignant arrhythmia as a cause of syncope in certain inherited arrhythmia patients who are at low risk of sudden cardiac death. In this comprehensive literature review, we evaluate the available evidence for the use of the ILR in the IASs and in relatives of victims of sudden arrhythmic death syndrome.

The utility of the implantable loop recorder in patients with a diagnosis or family history of long QT syndrome

Abstract 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

Diagnostic yield of implantable loop recorders in patients with unexplained syncope: single-center experience.

A significant proportion of patients have syncope of uncertain etiology. While implantable loop recorder (ILR) has become an important diagnostic tool in diagnosing syncope, its contemporary role in accordance with the recently updated syncope guidelines is not well established. The purpose of this single-center retrospective study was to determine the diagnostic yield of ILR in patients with unexplained syncope following initial diagnostic work-up as recommended by the guidelines. Medical records of 100 consecutive patients with syncope or presyncope who received ILR following the recently updated recommended diagnostic work-up were retrospectively evaluated. Seven patients were lost to follow-up (7%). During a median follow-up of 12 months (IQR 6.5-27.5), syncope or presyncope recurred in 61 patients (65.6%). In 37 (37/61, 60.7%), correlation between abnormal heart rhythm and symptoms was confirmed by ILR. Syncope was predominantly caused by bradyarrhythmia (33/37, 89.2%). Of the remaining four patients, three (8.1%) had ventricular tachycardia and one had atrial fibrillation with rapid ventricular response. Arrhythmogenic cause of syncope or presyncope was excluded in 24 patients (24/61, 39.3%) as no arrhythmia was recorded at the time of reported symptoms. Median time to establishing diagnosis was 354 days (171-783). The diagnostic yield of ILR after initial inconclusive recommended diagnostic work-up in accordance with the relevant guidelines was high. The findings affirm ILR as an important diagnostic tool in contemporary management of syncope.

Implantable loop recorders in patients with heart disease: comparison between patients with and without syncope

ObjectivePatients with heart disease are at increased risk for sudden cardiac death. Guidelines recommend an implantable loop recorder (ILR) for symptomatic patients when symptoms are sporadic and possibly arrhythmia-related. In...

Diagnostic value of implantable loop recorders in patients with unexplained syncope or palpitations.

BackgroundThe implantable loop recorder (ILR) is a small cardiac rhythm‐monitoring device. Our aim was to determine ILR diagnostic value in patients with unexplained syncope, presyncope, or palpitations suggesting cardiac arrhythmias.MethodsThis has been a retrospective, observational, single‐center study. We included 181 patients in whom ILR was implanted at the Clinical Center of Serbia between January 2006 and July 2019. An event was marked as diagnostic if it led to a diagnosis and ILR was considered diagnostic if it verified or excluded an arrhythmia as the cause of syncope or palpitations.ResultsThe mean age was 51.8 ± 17.8 years and 94 (51.9%) were male. The mean follow‐up period was 20.2 ± 15.8 months. ILR was diagnostic in 98 patients (54.1%). There was no significant difference in diagnostic value of ILR in regard to the baseline patients’ characteristics. The mean time to occurrence of the diagnostic event was 11.1 ± 9.6 months. The time to occurrence of a diagnostic event did not differ significantly between patients who underwent basic as compared to extended diagnostics before ILR implantation.ConclusionsILR was able to achieve an etiological diagnosis in 54.1% of patients with unexplained syncope, presyncope, or palpitations suggesting cardiac arrhythmias. In a subgroup of patients with recurrent palpitations, ILR was significantly less diagnostic than in patients with syncope or presyncope. ILR should be implanted beforehand in syncope evaluation process.

Sex differences in echocardiographic predictors of bradycardia detected by implantable loop recorder in patients with syncope and palpitations.

Our aim was to investigate whether echocardiography may aid in identifying patients, specifically men, at risk of bradycardia as detected by implantable loop recorders (ILR) in patients evaluated for syncope and palpitations. We included ambulatory patients undergoing ILR implantation for syncope (84%), presyncope (9%), and palpitations (8%). Echocardiographic examination was performed prior to implantation (2.9months [IQR 1.0-6.0months]). Echocardiograms were analyzed for conventional and speckle tracking parameters. We examined time to first event of bradycardia, defined as (a) heart rate <30 beats/min and (b) ≥4 beats, including sinus arrest, asystole, sinoatrial block, and second- and third-degree atrioventricular nodal block. We applied Cox proportional hazards models. A total of 285 patients we enrolled, and during a median time of 2.7years [IQR 1.0, 3.3years] of continuous heart rhythm monitoring, 84 (29%) had bradycardia detected by ILR. Patients with bradycardia were older (61±19years vs 55±18years, P=.01) and more frequently men (62% vs 44%, P=.01). Sex modified the association between echocardiographic parameters and bradycardia (P interaction <0.05 for all), such that left ventricular LV mass index (HR: 1.02 per 1g/m2 increase [1.01-1.04], P<.001), LV ejection fraction (HR: 1.04 per 1% decrease [1.01-1.08], P=.02), and global longitudinal strain (HR: 1.09 per 1% decrease [1.01-1.19], P=.03) were associated with bradycardia in men but not women (P>.05 for all in female). After adjusting for baseline clinical characteristics, medical therapy, and loop indication, the abovementioned parameters remained significantly associated with incident bradycardia in men. Echocardiographic parameters of LV structure and function may potentially be more useful for predicting bradycardia in men than women, among patients undergoing ILR implantation for syncope, presyncope, and palpations.