Use of event recorders and loop recorders in clinical practice: results of the European Heart Rhythm Association Survey

Twenty-five years of research on syncope

Over the last 25 years, the Europace journal has greatly contributed to dissemination of research and knowledge in the field of syncope. More than 400 manuscripts have been published in the journal. They undoubtedly improved our understanding of syncope. This symptom is now clearly differentiated from other forms of transient loss of consciousness. The critical role of vasodepression and/or cardioinhibition as final mechanisms of reflex syncope is emphasized. Current diagnostic approach sharply separates between cardiac and autonomic pathways. Physiologic insights have been translated, through rigorously designed clinical trials, into non-pharmacological or pharmacological interventions and interventional therapies. The following manuscript is intended to give the reader the current state of the art of knowledge of syncope by highlighting landmark contributions of the Europace journal.

Ambulatory ECG monitoring for syncope and collapse in United States, Europe, and Japan: The patients' viewpoint

BACKGROUND

Practice guidelines provide clinicians direction for the selection of ambulatory ECG (AECG) monitors in the evaluation of syncope/collapse. However, whether patients' understand differences among AECG systems is unknown.

METHODS AND RESULTS

A survey was conducted of USA (n = 99), United Kingdom (UK)/Germany (D) (n = 75) and Japan (n = 40) syncope/collapse patients who underwent diagnostic AECG monitoring. Responses were quantitated using a Likert-like 7-point scale (mean ± SD) or percent of patients indicating a Top 2 box (T2B) for a particular AECG attribute. Patient ages and diagnosed etiologies of syncope/collapse were similar across geographies. Patients were queried on AECG attributes including the ability to detect arrhythmic/cardiac causes of collapse, instructions received, ease of use, and cost. Patient perception of the diagnostic capabilities and ease of use did not differ significantly among the AECG technologies; however, USA patients had a more favorable overall view of ICM/ILRs (T2B: 42.4%) than did UK/D (T2B: 28%) or Japan (T2B: 17.5%) patients. Similarly, US patient rankings for education received regarding device choice and operation tended to be higher than UK/D or Japan patients; nevertheless, at their best, the Likert scores were low (approximately 4.7-6.0) suggesting need for education improvement. Finally, both US and UK/D patients were similarly concerned with ICM costs (T2B, 31% vs 20% for Japan).

CONCLUSIONS

Patients across several geographies have a similar but imperfect understanding of AECG technologies. Given more detailed education the patient is likely to be a more effective partner with the clinician in establishing a potential symptom-arrhythmia correlation.

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

BACKGROUND

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.

METHODS

Medical records of 100 consecutive patients with syncope or presyncope who received ILR following the recently updated recommended diagnostic work-up were retrospectively evaluated.

RESULTS

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).

CONCLUSIONS

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.

External Loop Recorders: Primary Care Placement Is Noninferior to Hospital-Based Cardiac Unit

Introduction: External loop recorders (ELRs) are recommended for the investigation of syncope and palpitations. This study aimed to compare rates of arrhythmia detection between primary care (PC) and hospital-based cardiac unit (HBCU) fitted ELRs. Methods: Data were captured from January to December 2015. Twenty-eight general practitioner practices and 1 hospital took part. Patients were divided into those with ELR fitted in PC or HBCU. All ELR data were analyzed by a cardiac physiologist. Results: A total of 560 ELR recordings were analyzed; 219 (PC) versus 341 (HBCU). There was no difference between the baseline characteristics (all Ps > .05). The predominant indication for ELR in each group were palpitations; between-group variation was observed for syncope (P = .0004). There were no significant between-group differences in the number of recordings per patient; however, PC group wore the ELR for less time (median 7 days vs median 14 days; P < .0001). There were no differences in arrhythmia detection between PC- and HBCU-fitted ELRs (16.2% [n = 39] vs 21.7% [n = 74], respectively; P = .28). PC placement of ELRs was highest in very remote rural communities (P = .005) and correlated with distance from HBCU (r = 0.39; P = .04). Conclusions: This study showed no difference in detection of arrhythmias between PC and HBCU fitted ELRs. This suggests adequate ELR recording can be completed by suitably trained staff in PC. Furthermore, ELRs were fitted for less time in PC without an adverse effect on diagnostic yield. ELR usage increased with increasing distance from the specialist center and rurality suggesting improved local access to arrhythmia detection services.

Expert opinion on continuous rhythm monitoring of patients with atrial fibrillation for candidates or patients who have already undergone ablation

BACKGROUND

Continuous monitoring by implantable loop recorder (ILR) can provide information relevant to rhythm control and oral anticoagulation (OAC) after atrial fibrillation (AF) ablation, but there is little agreement on patients' selection and appropriate management strategy.

METHODS

An expert panel (EP) made up of eight Italian electrophysiologists with expertise in AF ablation, gathered to define an algorithm to guide continuous rhythm monitoring in AF patients who have undergone ablation. The process included a review of the current literature and two EP face-to-face meetings. Between the two meetings, an on-line survey was sent to 50 Italian electrophysiologists practicing AF ablation. Agreement level was considered reached when ≥70% of respondents agreed or were neutral.

RESULTS

Two algorithms were developed to define patients for whom the ILR would be suggested support for (OAC) therapy discontinuation and rhythm management after AF ablation. Thirty-three out of 50 physicians responded to on-line survey (66% response rate). Together with EP members the responders accounted for electrophysiology centers performing about 50% of total yearly Italian AF ablation procedures. Agreement level was reached at the first survey round on all the questions, so the algorithms were not further modified and re-tested.

CONCLUSIONS

EP developed two algorithms for ECG monitoring to guide OAC therapy discontinuation and rhythm management after AF ablation. These suggestions, validated by wide feedback and consensus of physicians performing AF ablations, might support the decision on the choice and the use of ECG monitoring techniques, based on specific patient characteristics.

Current practice of Dutch cardiologists in detecting and diagnosing atrial fibrillation: results of an online case vignette study

Introduction

Detection of atrial fibrillation (AF) is important given the risk of complications, such as stroke and heart failure, and the need for preventive measures. Detection is complicated because AF can be silent or paroxysmal. Describing current practice may give clues to improve AF detection. The aim of this study was to describe how cardiologists currently detect AF.

Methods

Between December 2014 and May 2015, we sent Dutch cardiologists an online questionnaire. Firstly, we asked which tools for detection of AF their department has. Secondly, we presented six case vignettes related to AF, in which they could choose a diagnostic tool. Thirdly, we compared the results with current guidelines.

Results

We approached 90 cardiology departments and 48 (53%) completed the questionnaire. In asymptomatic patients with risk factors according to CHA₂DS₂-VASc, 40% of the cardiologists would screen for AF. In patients with signs or symptoms of AF, all but one cardiologist would start a diagnostic process. In both vignettes describing patients with non-frequent symptoms, 46% and 54% of the responders would use short-term (i. e. 24- or 48-hour) electrocardiographic monitoring, 48% and 27% would use long-term (i. e. 7 day, 14 day or one month) monitoring. In both cases describing patients with frequent symptoms, 85% of the responders would use short-term and 15% and 4% long-term monitoring.

Conclusion

Dutch cardiologists have access to a wide variety of ambulatory arrhythmia monitoring tools. Nearly half of the cardiologists would perform opportunistic screening. In cases with non-frequent symptoms, monitoring duration was shorter than recommended by NICE.

Aborted sudden cardiac death in a patient with implantable loop recorder

We discuss a 46-year-old man with history of hypertension and inferior wall myocardial infarction and mild left ventricular dysfunction who presented with aborted sudden cardiac death due to episodes of ventricular tachyarrhythmia detected by a Reveal-LINQ which had been implanted one year prior to presentation.

Efficacy And Safety Of Implantable Loop Recorder: Experience Of A Center

Introduction: Symptoms like syncope or palpitations frequently present a diagnostic challenge. An implantable loop recorder (ILR) is an important aid in the management of these patients. Methods: A retrospective study of patients that underwent ILR implantation from November 2007 to 2014. For each patient the indication for implantation, baseline characteristics, previous study, complications, recorded tracing and interventions were evaluated. Results: A total of 62 patients were included, 50% men, with a mean age of 62.5±18.8 years old. Previously to ILR implantation 88.7% of patients had performed Holter, 17.7% external events recorder, 33.9% Tilt test and 29% an electrophysiological study. The implantation indications were recurrent syncope in 90.3%, palpitations 8.1% and ischemic stroke in one patient. Mean follow-up time was 17.1±16.3 months. Symptoms were reported in 66.1% of the patients, 46.8% of those yielding a diagnostic finding. In all cases of palpitation complaints with diagnosis we found atrial fibrillation (AF). In patients with syncope atrioventricular conduction disturbance was demonstrated in 19.6%, sinus node dysfunction in 16.1%, paroxysmal supra-ventricular tachycardia 7.1% and AF in 1.8%. These finding resulted in 19 pacemaker and one CRT-D implantation, introduction of anticoagulation in five patients and one ablation of accessory pathway. There were no major complications. Conclusion: ILR proved to be safe and efficient. It has enabled the identification or exclusion of serious rhythm disturbances in more than half of patients and provided a targeted therapeutic intervention.

Efficacy And Safety Of Implantable Loop Recorder: Experience Of A Center

Introduction: Symptoms like syncope or palpitations frequently present a diagnostic challenge. An implantable loop recorder (ILR) is an important aid in the management of these patients. Methods: A retrospective study of patients that underwent ILR implantation from November 2007 to 2014. For each patient the indication for implantation, baseline characteristics, previous study, complications, recorded tracing and interventions were evaluated. Results: A total of 62 patients were included, 50% men, with a mean age of 62.5±18.8 years old. Previously to ILR implantation 88.7% of patients had performed Holter, 17.7% external events recorder, 33.9% Tilt test and 29% an electrophysiological study. The implantation indications were recurrent syncope in 90.3%, palpitations 8.1% and ischemic stroke in one patient. Mean follow-up time was 17.1±16.3 months. Symptoms were reported in 66.1% of the patients, 46.8% of those yielding a diagnostic finding. In all cases of palpitation complaints with diagnosis we found atrial fibrillation (AF). In patients with syncope atrioventricular conduction disturbance was demonstrated in 19.6%, sinus node dysfunction in 16.1%, paroxysmal supra-ventricular tachycardia 7.1% and AF in 1.8%. These finding resulted in 19 pacemaker and one CRT-D implantation, introduction of anticoagulation in five patients and one ablation of accessory pathway. There were no major complications. Conclusion: ILR proved to be safe and efficient. It has enabled the identification or exclusion of serious rhythm disturbances in more than half of patients and provided a targeted therapeutic intervention.

[Implantable loop recorder in atrial fibrillation and after catheter ablation]

BACKGROUND

Implantable loop recorders (ILR) are an established diagnostic method for detection of cardiac arrhythmias including atrial fibrillation.

OBJECTIVE

The aim of this work is to provide an overview of available data and indications of ILR in atrial fibrillation, especially after catheter ablation, in order to illustrate practice-oriented recommendations.

MATERIALS AND METHODS

We conducted a selective PubMed literature search.

RESULTS AND DISCUSSION

ILR can record asymptomatic/rare atrial fibrillation episodes and prevent thromboembolic events by allowing timely initiation of oral anticoagulation. They can be used to assess therapeutic success after percutaneous or surgical ablation, if despite increased thromboembolic risk, no oral anticoagulation is desired. ILR equipped with remote monitoring function and special P wave detection algorithms may improve diagnostic confidence.

Holter Monitoring and Loop Recorders: From Research to Clinical Practice

Holter monitors are tools of proven efficacy in diagnosing and monitoring cardiac arrhythmias. Despite the fact their use is widely prescribed by general practitioners, little is known about their evolving role in the management of patients with cryptogenic stroke, paroxysmal atrial fibrillation, unexplained recurrent syncope and risk stratification in implantable cardioverter defibrillator or pacemaker candidates. New Holter monitoring technologies and loop recorders allow prolonged monitoring of heart rhythm for periods from a few days to several months, making it possible to detect infrequent arrhythmias in patients of all ages. This review discusses the advances in this area of arrhythmology and how Holter monitors have improved the clinical management of patients with suspected cardiac rhythm diseases.

Insertable cardiac monitors in the diagnosis of syncope and the detection of atrial fibrillation: A systematic review and meta-analysis

BACKGROUND

Insertable or implantable cardiac monitors (ICMs) continuously monitor the heart rhythm and record irregularities over 3 years, enabling the diagnosis of infrequent rhythm abnormalities associated with syncope and stroke. The enhanced recognition capabilities of recent ICM models are able to accurately detect atrial fibrillation (AF) and have led to new applications of ICMs for the detection and monitoring of AF.

METHODS AND RESULTS

Based on a systematic literature search, two indications were identified for ICMs for which considerable evidence, including randomized studies, exists: diagnosing the underlying cardiac cause of unexplained recurrent syncope and detecting AF in patients after cryptogenic stroke (CS). Three randomized controlled trials (RCTs) were identified that compared the effectiveness of ICMs in diagnosing patients with unexplained syncope (n = 556) to standard of care. A meta-analysis was conducted in order to generate an overall effect size and confidence interval of the diagnostic yield of ICMs versus conventional monitoring. In the indication CS, one RCT and five observational studies were included in order to assess the performance of ICMs in diagnosing patients with AF (n = 1129). Based on these studies, there is strong evidence that ICMs provide a higher diagnostic yield for detecting arrhythmias in patients with unexplained syncope and for detection of AF in patients after CS compared to conventional monitoring.

CONCLUSIONS

Prolonged monitoring with ICMs is an effective tool for diagnosing the underlying cardiac cause of unexplained syncope and for detecting AF in patients with CS. In all RCTs, ICMs have a superior diagnostic yield compared to conventional monitoring.

EHRA research network surveys: 6 years of EP wires activity

Clinical practice should follow guidelines and recommendations mainly based on the results of controlled trials, which are often conducted in selected populations and special conditions, whereas clinical practice may be influenced by factors different from controlled scientific studies. Hence, the real-world setting is better assessed by the observational registries enrolling patients for longer periods of time. However, this may be difficult, expensive, and time-consuming. In 2009, the Scientific Initiatives Committee of the European Heart Rhythm Association (EHRA) has instigated a series of surveys covering the controversial issues in clinical electrophysiology (EP). With this in mind, an EHRA EP research network has been created, which included EP centres in Europe among which the surveys on 'hot topic' were circulated. This review summarizes the overall experience conducting EP wires over the past 6 years, categorizing and assessing the topics regarding clinical EP, and evaluating the acceptance and feedback from the responding centres, in order to improve participation in the surveys and better address the research needs and aspirations of the European EP community.

Use of a Patient-Activated Event Recording System in Patients with Tachycardic Palpitations: How Long to Follow Up?

INTRODUCTION

Palpitations are a common symptom causing patients to consult a cardiologist, yet diagnosing a potential cardiac origin can be difficult. In patients with a nondiagnostic Holter-ECG, external loop-recorders are an additional tool to diagnose the clinical arrhythmia in these patients. The aim of our study was to evaluate the additional value of an external, patient-activated loop recorder and to determine the optimal time of follow up needed to achieve a symptom-rhythm correlation with the device.

METHODS AND RESULTS

A total of 1404 patients presented to our outpatient clinic between November 2011 and November 2014 for first time evaluation of symptomatic arrhythmias. Of a total of 91 patients were included (age 43.6±18.1; 69.2% female) in the study. All patients presented with tachycardic palpitations and a 48-hour Holter-ECG that did not detect relevant arrhythmias. All patients were given a "leadless" patient-activated event-recording system and regular follow-up visits were scheduled after 3, 6, and 12 months. Within a maximum follow-up time of 1 year, 72 patients (79.1%) recorded at least one ECG with the device. Of the recorded ECGs, 51% were recorded within the first week after the device was handed out. This figure rises to 80% and 93% after 1 and 2 months. The last recording was after 174 days.

CONCLUSION

For patients with tachycardic palpitations, the external "leadess" event recorders are effective in achieving a symptom-rhythm correlation. A follow up of 2 months will suffice to establish a diagnosis in a large majority of this patient group.

The cold facts of long-term ECG monitoring

Two recently published trials have provided evidence in favor of longer ECG monitoring among patients with cryptogenic stroke (CS). In the CRYSTAL-AF trial, new atrial fibrillation (AF) was detected in 12.4% of patients with implantable monitor when compared with 2% among those receiving standard follow-up. A similar result was observed in the EMBRACE trial in which AF was detected in 16.1% of patients who received 30-day event recorder (3.2% in controls). These data are compelling in convincing us that long-term ECG technologies have superior sensitivity for the detection of AF in CS; however, clinical specificity for the definition of CS etiology of such findings cannot be established and can be lower than expected, leaving open questions about the etiologic weight of AF in CS. The causative role of AF in this subpopulation remains to be proven, and diagnostic routes cannot be solely unbalanced toward the research of AF.