Are Implantable Loop Recorders Useful in Detecting Arrhythmias in Children with Unexplained Syncope?

The Evolving Role of Insertable Cardiac Monitors in Patients with Congenital Heart Disease

Insertable cardiac monitors (ICMs) have been used more frequently and in a wider variety of circumstances in recent years. ICMs are used for symptom-rhythm correlation when patients have potentially arrhythmogenic syncope and for less traditional reasons such as rhythm surveillance in patients with genetic arrhythmia syndromes or other diseases with high arrhythmia risk. ICMs have good diagnostic yield in pediatric patients and in adults with congenital heart disease and have a low rate of complications. Implantation techniques should take patient-specific factors into account to optimize diagnostic yield and minimize risk.

Implantable Loop Recorder with Long Sensing Vector: Safety, Acceptability, and Sensing Performance in Pediatric Patients

Implantable loop recorders (ILRs) are effective tools for detecting arrhythmias by long-term continuous heart rhythm monitoring. Benefits have been demonstrated even in pediatric patients. ILR with a long sensing vector has recently been designed to improve signal quality in terms of P wave visibility and R wave amplitude. However, there are no data on its use in pediatric patients. We considered a series of pediatric patients implanted with a long sensing vector ILR. Sensing performance, including R wave amplitude and P wave visibility, device-related complications, and diagnostic yield were collected. During follow-up, each patient guided by his/her parents/guardians was also asked to complete a brief questionnaire to assess patient acceptability of the device. Twenty-five consecutive pediatric patients (mean age 11.3 ± 3.5 years, 72% male) were enrolled. The insertion success rate was 100% on the first attempt with no complications. The median amplitude of the R wave was 1.15 mV (interquartile range, 1.01-1.42) with no significant differences between patients aged ≤ or > 10 years (p = 0.726) and between female and male (p = 0.483). P wave was classified as 'always visible' in 24/25 patients (96%). ILR was generally well accepted and tolerated by all involved patients. During a median follow-up of 297 days (117-317), we achieved in 5 patients a correlation between symptoms and rhythm disorders (20%) and ruled out significant arrhythmias in 6 symptomatic children (24%). Long sensing vector ILR showed to be well accepted, with good signal quality and an excellent safety profile even in pediatric patients.

The Role of External Loop Recorders in Arrhythmia-Related Symptoms in Children: A Single Center Experience

In this study, we report our experience with the use of external loop recorders (ELRs), in terms of diagnostic efficiency according to symptoms and symptom-rhythm correlation in pediatric patients. We evaluated ELRs applied to 178 patients between April 2017 and November 2020 at our center. The mean age of 172 patients included in the study was 13.6 ± 3.8 years, and 69.8% were female. ELR indications were palpitations in 98 (56.9%) cases, chest pain and palpitations in 43 (25%) cases, presyncope/syncope in 28 (16.2%) cases, and pacemaker/ implantable cardioverter-defibrillator (ICD) problems in 3 (0.2%) cases. ELR recording times were 14.2 ± 9.7 days on average, ranging from 2 to 67 days. While the symptom-rhythm correlation was 29.1% in total, when the indications were evaluated one by one, this correlation was found to be 30.2% in palpitations, 34.7% in chest pain and palpitations, and 10.7% in presyncope/syncope. The total diagnostic efficiency was 68.1%. In the follow-up of ELR cases, a total of 139 (80.8%) patients received clinical follow-up without medication, 15 (8.8%) patients received medical treatment, and 18 (10.4%) patients underwent EPS. The cardiac ELR system is useful in detecting underlying arrhythmias. Demonstrating sinus tachycardia at the time of the symptom may be seen as negative finding, but while experiencing symptoms, it is diagnostically valuable and may help avoid further investigation with costly and invasive diagnostic procedures. For diagnostic efficiency and cost effectiveness, the optimal recording time is 2 weeks, but it should be extended to 4 weeks in cases such as of presyncope/syncope that cannot be explained with a 2-week ELR use.

2021 PACES Expert Consensus Statement on the Indications and Management of Cardiovascular Implantable Electronic Devices in Pediatric Patients: Developed in collaboration with and endorsed by the Heart Rhythm Society (HRS), the American College of Cardiology (ACC), the American Heart Association (AHA), and the Association for European Paediatric and Congenital Cardiology (AEPC) Endorsed by the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS)

In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consensus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology (ACC), and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate CIED follow-up in pediatric patients.

2021 PACES expert consensus statement on the indications and management of cardiovascular implantable electronic devices in pediatric patients

In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consensus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology (ACC), and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate CIED follow-up in pediatric patients.

2021 PACES Expert Consensus Statement on the Indications and Management of Cardiovascular Implantable Electronic Devices in Pediatric Patients

In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consenus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology, (ACC) and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate follow-up in pediatric patients.

2021 PACES Expert Consensus Statement on the Indications and Management of Cardiovascular Implantable Electronic Devices in Pediatric Patients

In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consensus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology (ACC), and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate CIED follow-up in pediatric patients.

Placement of Reveal LINQ Device in the Left Anterior Axillary Position

Implantable loop recorders (ILR) are utilized for long-term rhythm monitoring. Typical placement of the Medtronic Reveal LINQ along the left parasternal border may compromise the quality and/or feasibility of future imaging studies. We sought to evaluate the utility of placing an ILR in the left anterior axillary position and the impact on the quality of cardiac imaging. We reviewed patients from May 2017 to June 2018 who had placement of a Reveal LINQ device in the left anterior axillary position. Demographic, procedural, and clinical data were collected via retrospective review. Cardiac magnetic resonance imaging (MRI) studies were reviewed for image quality after ILR placement. Eight patients met inclusion criteria for this study (median age 6 years, 50% female). Six patients (75%) had an ILR placed in the operating room, while all others were placed in the electrophysiology lab. All patients demonstrated acceptable R waves for diagnostic evaluation (median = 0.85 mV, range 0.24-1.7 mV). Cardiac MRI was obtained in 7 patients following ILR placement with diagnostic image quality and no adverse events. One device was explanted 28 days after placement due to concern for possible infection. No other devices required removal or revision (median follow up duration 11 months, IQR 8-13.5). ILR placement in the left anterior axillary position can record adequate signals in pediatric patients. In addition, axillary ILR device position may allow for completion of cardiac imaging, particularly cardiac MRI, without significant artifacts which is critical for patients with congenital heart disease.

Reveal LINQ Versus Reveal XT Implantable Loop Recorders: Intra- and Post-Procedural Comparison

OBJECTIVES

To compare the procedure, recovery, hospitalization times, and costs along with patient/parent satisfaction after newer-generation cardiac implantable loop recorder (Reveal LINQ; Medtronic Inc, Minneapolis, Minnesota) and previous-generation implantable loop recorder (Reveal XT; Medtronic Inc).

STUDY DESIGN

A prospective study of patients undergoing LINQ implantations between April 2014 and October 2015 was performed. Retrospective chart review of patients undergoing XT implantations was performed for comparison.

RESULTS

Thirty-one patients received LINQ and 15 patients received XT. Indications included syncope/palpitations (28/46, 61%), history of arrhythmias (9/46, 20%), arrhythmia burden in congenital heart disease (5/46, 10%), and monitoring in channelopathies (4/46, 9%). The LINQ group underwent more conscious sedation procedures than the XT group (8/31 vs 0/15, P = .04) with shorter procedural time (9 vs 34 minutes, P <.001), room occupation time (38 vs 81 minutes, P <.001), recovery time (21 vs 67 minutes, P <.001), and total hospital time (214 vs 264 minutes, P = .046). The LINQ group also had shorter return to activity time (2 vs 5 days, P = 1). Three device erosions in the LINQ group required reintervention. The LINQ group had fewer body image issues than the XT group (1/26 vs 5/14, P = .01) with both groups scoring 5/5 overall patient/parent satisfaction score at follow-up. Both groups had comparable total direct hospital costs (US $5905 vs $5438, P = .8).

CONCLUSIONS

LINQ offers better procedural and recovery time compared with XT. LINQ implantations under conscious sedation reduce total hospitalization time.

PocketECG: A New Noninvasive Method for Continuous and Real-Time ECG Monitoring-Initial Results in Children and Adolescents

Long-term ECG is widely used in diagnosis and assessment of many cardiac symptoms which may be caused by dangerous arrhythmias that sometimes can be difficult to document. The PocketECG system is a new technological solution for a long-term, noninvasive, continuous and real-time ECG monitoring that provides automatic diagnosis of dysrhythmias. ECG data transmission occurs over a mobile network. The goal of this study was to assess the reliability of long-term ECG recordings acquired with the PocketECG system. One hundred and fifteen patients (43 girls and 72 boys) of an average age of 15.5 ± 2.5 years were examined at the Department of Cardiology at the Children's Memorial Health Institute. Two simultaneous 24-h ECG recordings were conducted: one with a Holter monitor and one with the PocketECG system. A linear correlation was demonstrated between the two methods with regard to the recorded QRS complexes [H = 1173.0 (-1946.40; 4838.50) + PocketECG*0.98 (0.94; 1.02)]. Mean diurnal heart rhythms were comparable (p > 0.05) despite the fact that the slowest and the fastest rates were different. The rate of detection for ventricular, supraventricular dysrhythmias and pauses in ventricular rhythm were comparable in both methods. The PocketECG system for continuous and real-time ECG recording is a reliable method for the assessment of heart rhythm and dysrhythmias in children and adolescents.

P- and R-wave Amplitude Sensed by Reveal LINQ™ Loop Recorder in Pediatric Patients

Implantable loop recorders are commonly used to sense arrhythmias. The purpose of this study is to assess the P- and R-wave amplitudes at implantation (I) and follow-up (F) following insertion of the Reveal LINQ™ Insertable Cardiac Monitor (Medtronic, Minneapolis, MN) in an institutional review board-approved, multicenter study performed on pediatric patients younger than 18 years old. Collected data included demographics, presence of congenital heart disease (CHD), P- and R-wave-sensed amplitude at I and F, and the method of implant (i.e. mapping or standard.) P waves were manually measured and R-wave sensing was recorded by the device. A total of 87 patients had a Reveal LINQ™ (Medtronic, Minneapolis, MN) device implanted; the mean patient age was 11.8 years (0.5 years to 18 years) with 48% of patients being female and 19% of patients having CHD; mapping was used in 43% of patients. The Reveal LINQ™ (Medtronic, Minneapolis, MN) experienced no change in average sensed R-wave amplitude at either I or F (1.28 mV vs 1.26 mV, p = NS). There was no difference in sensed R-wave amplitude noted with or without mapping used at I (1.29 mV vs 1.26 mV, p = NS) or F (1.48 mV vs 1.18 mV, p = NS). Additionally, no difference could be found in R-wave sensing of patients with CHD or without CHD at I (1.26 mV vs 1.4 mV, p = NS) or F (1.32 mV vs 1.32 mV, p = NS). R-wave sensing trended towards being inversely proportional to patient body surface area (BSA) (p = NS). P waves were detected on 48% of tracings in all patients at I and/or F, irrespective of whether the Reveal LINQ™ (Medtronic, Minneapolis, MN) device was placed with mapping. The R wave was (0.37–3.5 mV) at I and (0.3–3 mV) (p = NS) at F when P waves were detected. From these results, it can be said that the Reveal LINQ™ Insertable Cardiac Monitor (Medtronic, Minneapolis, MN) has an excellent ability to sense R-wave amplitude in pediatric patients. No significant difference in the sensing ability of the device could be identified with respect to the presence of CHD, use of mapping or BSA. P waves tended to be identified when there was a higher baseline R-wave amplitude.

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.

Implantable Loop Recorder Monitoring for Refining Management of Children With Inherited Arrhythmia Syndromes

BACKGROUND

Implantable loop recorders (ILRs) are conventionally utilized to elucidate the mechanism of atypical syncope. The objective of this study was to assess the impact of these devices on management of pediatric patients with known or suspected inherited arrhythmia syndromes.

METHODS AND RESULTS

A retrospective chart review was undertaken of all pediatric patients with known or suspected inherited arrhythmia syndromes in whom an ILR was implanted from 2008 to 2015. Captured data included categorization of diagnosis, treatment, transmitted tracings, and the impact of ILR tracings on management. Transmissions were categorized as symptomatic, autotriggered, or routine. Actionable transmissions were abnormal tracings that directly resulted in a change of medical or device therapy. A total of 20 patients met the stated inclusion criteria (long QT syndrome, n=8, catecholaminergic polymorphic ventricular tachycardia,n=9, Brugada syndrome, n=1, arrhythmogenic right ventricular cardiomyopathy, n=2), with 60% of patients being genotype positive. Primary indication for implantation of ILR included ongoing monitoring +/- symptoms (n=15, 75%), suspicion of noncompliance (n=1, 5%), and liberalization of recommended activity restrictions (n=4, 25%). A total of 172 transmissions were received in patients with inherited arrhythmia syndromes, with 7% yielding actionable data. The majority (52%) of symptom events were documented in the long QT syndrome population, with only 1 tracing (5%) yielding actionable data. Automatic transmissions were mostly seen in the catecholaminergic polymorphic ventricular tachycardia cohort (81%), with 21% yielding actionable data. There was no actionable data in routine transmissions.

CONCLUSIONS

ILRs in patients with suspected or confirmed inherited arrhythmia syndromes may be useful for guiding management. Findings escalated therapies in 30% of subjects. As importantly, in this high-risk population, the majority of symptom events represented normal or benign rhythms, reassuring patients and physicians that no further intervention was required.

Using a Cardiac Event Recorder in Children with Potentially Arrhythmia-Related Symptoms

BACKGROUND

In this study, we reported our experience with the use of cardiac event recorders in pediatric patients.

METHODS

We evaluated 583 patients fitted with an event recorder (15-30 days) between March 2010 and November 2014 at our clinic. Excluded from the study were 117 patients with no recorded events and six with records contaminated by electrocardiogram artifacts. All of the patients received electrocardiograms, Holter monitoring, and echocardiography before the cardiac event recording.

RESULTS

The patient sample consisted of 460 patients (64% female). The mean age was 12.8 ± 4.1 years. The median number of recorded events was 7. The indications included palpitations in 336 (73%) patients, syncope in 27 (6%) patients, and chest pain and palpitations in 97 (21%) patients. Whereas 64 patients (14%) had structural heart disease according to echocardiographic examination, the remaining patients had normal echocardiographic examination results. The most frequent cardiac comorbidities were mitral valve prolapse (6%), operated tetralogy of Fallot (1.5%), and complicated congenital heart diseases with single ventricle physiology (1%). The recorded events were sinus tachycardia in 113 (25%) patients, supraventricular tachycardia in 35 (8%) patients, ventricular extrasystole in 20 (4%) patients, supraventricular extrasystole in nine (2%) patients, and ventricular tachycardia in two (0.4%) patients. Based on the event recorder and follow-up electrocardiogram findings, 46 patients received an electrophysiology study/ablation. The symptom-rhythm correlation was 39%.

CONCLUSION

In the presence of possible arrhythmia-related symptoms in children, a cardiac event recorder can be considered a useful primary diagnostic method. More research on this topic is needed.

Syncope unit in the paediatric population: A single-centre experience

BACKGROUND

Syncopes are frequent in the paediatric population. Most are benign, but rare cases are caused by cardiac life-threatening diseases. Syncope units developed in the adult population have demonstrated improvement in evaluation and treatment, with a reduction in hospitalization.

AIMS

We report our experience of paediatric syncope management in a dedicated unit, and analyse the value of different elements in the identification of cardiac causes.

METHODS

This prospective study included 97 consecutive patients (mean age: 12.1±3.3 years) referred between January 2011 and June 2013 to a syncope unit with a paediatric cardiologist, a nurse, a physiotherapist and a psychologist. Patients were classified into diagnostic categories after an initial evaluation that included history, physical examination, electrocardiography, echocardiography and Holter monitoring.

RESULTS

The most common diagnosis was neurocardiogenic syncope (n=69, 70.4%). Fifty-two cases (81.3%) had no or less recurrence after specific management that included physiotherapy and psychological support (follow-up: 11.5±5.4 months). Psychogenic pseudosyncopes affected 20 children (20.6%). Two patients had epileptic seizures. There were five cases of cardiac syncope (5.1%): two long QT syndromes and a catecholaminergic polymorphic ventricular tachycardia received beta-blockers; two atrioventricular complete blocks required pacemakers. One case was of indeterminate cause and received an insertable loop recorder after exhaustive investigations. Exercise-induced syncopes were significantly associated with cardiac origins (P=0.003), such as electrocardiographic abnormalities (P<0.001), whereas echocardiography was not contributive.

CONCLUSION

Syncope units in the paediatric population may be useful in the diagnostic process, to help identify rare cardiac aetiologies, and could decrease recurrence through specific management.

Value of Ambulatory Electrocardiographic Monitoring in Syncope

Implantable loop recorders (ILRs) continuously monitor electrocardiographic signals and perform real-time analysis of heart rhythm for up to 36 months. ILRs are used to evaluate transitory loss of consciousness from possible arrhythmic origin, particularly unexplained syncope, and to evaluate difficult cases of epilepsy and unexplained falls, although current indications for their application in these areas are less clearly defined. This article analyzes the current indications for ILRs according the European Society of Cardiology guidelines on the management of syncope and the European Heart Rhythm Association guidelines on the use of implantable and external electrocardiogram loop recorders, and their limitations.

Improved quality of life after treatment of prolonged asystole during breath holding spells with a cardiac pacemaker

Objectives:

To validate the physical and psychological effectiveness of cardiac pacing in pediatric patients with breath-holding spells (BHS) and prolonged asystole.

Materials and Methods:

The records and clinical data of all the patients with BHS who presented to our center in the period of 2001–2013 were reviewed. All patients who received cardiac pacemaker implantation for prolonged asystole during BHS were included. In addition, the parents were asked to fill out a standardized quality of life (QOL) questionnaire.

Results:

Seven patients were identified. The mean onset of symptoms was 7 month (1–12 months) of age, documented asystole was 12–21 seconds, and a permanent cardiac pacemaker device was implanted at a mean age of 23 months (8 months–3.9 years). No pacemaker related adverse events were recorded. Follow up showed immediate resolution from spells in four cases (4/7). Two patients (2/7) showed significant reduction of frequency and severity of spells, with complete elimination of loss of consciousness (LOC). One patient (1/7) with an additional neurologic disorder continued to have minor pallid BHS and eventually switched from pallid to cyanotic spells without further detection of bradycardia or asystole in holter examination. QOL questionnaire revealed significant reduction in subjective stress levels of patients (P = 0.012) and parents (P = 0.007) after pacemaker implantation.

Conclusion:

Cardiac pacing using appropriate pacemaker settings seems effective in the prevention of LOC and reduction of the frequency of BHS. Our results imply a reduction of subjective stress levels of patients and parents as well as an increased quality of everyday life. After all, randomized controlled trials of the influence of cardiac pacemaker implantation on subjective stress levels in patients with BHS are needed.

Evaluation rhythm problems in unexplained syncope etiology with implantable loop recorder

BACKGROUND

Syncope is a frequent complaint in children and adolescents and may be a significant sign of serious pathology. Although patient history, family history, and physical examination are sufficient to reach a diagnosis in most cases of syncope, the cause of syncope still cannot be determined after initial investigation in one-third to half of all patients. The aim of this study was to evaluate the diagnostic yield of implantable loop recorder (ILR) in children with unexplained syncope.

METHODS

A retrospective review was carried out of clinical data, indications, findings, and a final management strategy in patients who underwent ILR implantation.

RESULTS

A total of 12 patients with a mean age of 9.4 ± 4.5 years underwent ILR (Reveal Plus; Medtronic) implantation. ILR implantation indication was syncope in all of the patients. Family history, routine cardiac assessment, including resting 12-lead electrocardiogram, transthoracic echocardiography, 24 h Holter recording, and event recorder findings, were normal with the exception of one patient with (previously corrected) tetralogy of Fallot. After an average of 20 months (range, 1-36 months), six patients developed symptoms. ILR memory showed torsades de pointes-ventricular fibrillation (n = 3), catecholaminergic polymorphic ventricular tachycardia (n = 1), asystole and ventricular tachycardia (n = 1), and normal sinus rhythm (n = 1). At the time of writing six patients were still in follow up with no symptoms after an average of 25.2 months.

CONCLUSION

Implantable loop recorder plays an important role in the diagnosis of life-threatening arrhythmias in which syncope is otherwise unexplained. ILR implantation should be remembered in children whose symptoms are strongly correlated with rhythm disturbances.

Current and emerging indications for implantable cardiac monitors

Implantable cardiac monitors (ICMs) continuously monitor the patient's electrocardiogram and perform real-time analysis of the heart rhythm, for up to 36 months. The current clinical use of ICMs involves the evaluation of transitory symptoms of possible arrhythmic origin, such as unexplained syncope and palpitations. Moreover, ICMs can also be used for the evaluation of difficult cases of epilepsy and unexplained falls, though current indications for their application in these sectors are less clearly defined. Finally, the ability of new-generation ICMs to automatically record arrhythmic episodes suggests that these devices could also be used to study asymptomatic arrhythmias, and thus could be proposed for the long-term evaluation of the total (symptomatic and asymptomatic) arrhythmic burden in patients at risk of arrhythmic events. In particular, ICMs may have an emerging role in the management of patients with atrial fibrillation and in those at risk of ventricular arrhythmias.