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

Contemporary Considerations in the Evolution of Wearable Technology for Arrhythmia Detection

Arrhythmias are an increasingly common cause of hospital admissions worldwide. Late detection of arrhythmias is associated with a significantly increased risk of cardiovascular complications. Early identification and management of life-threatening arrhythmias is paramount to reduce mortality. Wearable technologies are now widespread among the general population, providing a continuous output of healthcare data. However, this data are not routinely integrated into clinical practice. Here, we begin by outlining the current landscape in wearable technology for aiding arrhythmia detection; we then consider the clinical impact of wearable technology for both clinicians and patients; we further highlight the latest and emerging trials in wearable technology for arrhythmia detection and finally postulate the wider implications of the expansion of such cardiac devices.

The future of cardioneuroablation in cardiovascular medicine

INTRODUCTION

Cardioneuroablation is increasingly being utilized to improve outcomes in patients with vagally mediated bradyarrhythmias. However, there are still controversial issues in the field including patient selection, safety and efficacy, and procedural end-points.

AREAS COVERED

In this review, the current role of cardioneuroablation is summarized, and controversial issues related to the modality are discussed.

EXPERT OPINION

According to small open-label cohort studies, overall freedom from syncope recurrence was higher than 90% after cardioneuroablation in patients with vasovagal syncope (VVS). Use of the electrogram-based strategy or high-frequency stimulation demonstrate similar success rate except in procedures limited to the right atrium. Based on a recently published randomized controlled trial and metanalysis, it may be possible now to make a strong recommendation for cardioneuroablation in patients <40 years of age, and those with the cardioinhibitory or mixed type of VVS who continue to experience frequent and/or burdensome syncope recurrences. Considering patients with VVS are prone to significant placebo/expectation effect, sham-controlled trials may help to quantify the placebo effect. In well-selected patients with functional atrioventricular block and sinus bradycardia, may result in encouraging medium-term outcomes. However, functional bradycardia is identified in a minority of patients presenting with high-grade atrioventricular block or sinus node dysfunction.

Diagnostic Yield, Outcomes, and Resource Utilization With Different Ambulatory Electrocardiographic Monitoring Strategies

Accurate diagnosis of arrhythmias is improved with longer monitoring duration but can risk delayed diagnosis. We compared diagnostic yield, outcomes, and resource utilization by arrhythmia monitoring strategy in 330 matched adults (mean age 64 years, 40% women, and 30% non-White) without previously documented atrial fibrillation or atrial flutter (AF/AFL) who received ambulatory electrocardiographic monitoring by 14-day Zio XT (patch-based continuous monitor), 24-hour Holter, or 30-day event monitor (external loop recorder) between October 2011 and May 2014. Patients were matched by age, gender, site, likelihood of receiving Zio XT patch, and indication for monitoring, and subsequently followed for monitoring results, management changes, clinical outcomes, and resource utilization. AF/AFL ≥30 seconds was noted in 6% receiving Zio XT versus 0% by Holter (p = 0.04) and 3% by event monitor (p = 0.07). Nonsustained ventricular tachycardia was noted in 24% for Zio XT patch versus 8% (p <0.001) for Holter and 4% (p <0.001) for event monitor. No significant differences between monitoring strategies in outcomes or resource utilization were observed. Prolonged monitoring with 14-day Zio XT patch or 30-day event monitor was superior to 24-hour Holter in detecting new AF/AFL but not different from each other. Documented nonsustained ventricular tachycardia was more frequent with Zio XT than 24-hour Holter and 30-day event monitor without apparent increased risk of adverse outcomes or excess utilization. In conclusion, additional efforts are needed to further personalize electrocardiographic monitoring strategies that optimize clinical management and outcomes.

The utility of implantable loop recorders (ILR) in patient management: an age and indication stratified study in the outpatient-implant era

INTRODUCTION

Implantable loop recorders (ILR) are now routinely implanted for long-term cardiac monitoring in the clinic setting. This study examined the real-world performance of these devices, focusing on the management decision changes made in response to ILR-recorded data.

METHODS AND RESULTS

This was a single centre, prospective observational study of consecutive patients undergoing ILR implantation. All patients who underwent implantation of a Medtronic Reveal LINQ device from September 2017 to June 2019 at Barts Heart Centre were included.501 patients were included. 302 (60%) patients underwent ILR implantation for an indication of pre-syncope/syncope, 96 (19%) for palpitations, 72 (14%) for atrial fibrillation (AF) detection with a history of cryptogenic stroke and 31 (6%) for patients deemed to be high risk of serious cardiac arrhythmia.The primary outcome of this study was that an ILR-derived diagnosis altered management in 110 (22%) of patients. Secondary outcomes concerned sub-group analyses by indication: in patients who presented with syncope/presyncope, a change in management resulting from ILR data was positively associated with age (HR: 1.04 [95%CI 1.02-1.06]; p < 0.001) and negatively associated with a normal ECG at baseline (HR 0.54 [0.31-0.93]; p = 0.03). Few patients (1/57, 2%) aged < 40 years in this group underwent device implantation, compared to 19/62 patients (31%) aged 75 years and over (p = 0.0024). 22/183 (12%) of patients in the 40-74 age range had a device implanted.In patients who underwent ILR insertion following cryptogenic stroke, 13/72 patients (18%) had AF detected leading to a decision to commence anticoagulation.

CONCLUSION

These results inform the utility of ILR in the clinical setting. Diagnoses provided by ILR that lead to changes in management are rare in patients under age 40, particularly following syncope, presyncope or palpitations. In older patients new diagnoses are frequently made and trigger important changes in treatment.

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

OBJECTIVE

Patients 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 clinical practice, an ILR is mainly used in patients with unexplained syncope. We aimed to compare the clinical value of an ILR in patients with heart disease and a history of syncope versus those with non-syncopal symptoms.

METHODS

In this observational single-centre study, we included symptomatic patients with heart disease who received an ILR. The primary endpoint was an actionable event which was defined as an arrhythmic event leading to a change in clinical management. The secondary endpoint was an event leading to device implantation.

RESULTS

One hundred and twenty patients (mean age 47±17 years, 49% men) were included. The underlying disease substrate was inherited cardiomyopathy (31%), congenital heart disease (28%), channelopathy (23%) and other (18%). Group A consisted of 43 patients with prior syncope and group B consisted of 77 patients with palpitations and/or near-syncope. The median follow-up duration was 19 months (IQR 8-36). The 3-year cumulative event rate was similar between groups with regard to the primary endpoint (38% vs 39% for group A and B, respectively, logrank p=0.54). There was also no difference in the 3-year cumulative rate of device implantation (21% vs 13% for group A and B, respectively, logrank p=0.65).

CONCLUSION

In symptomatic patients with heart disease, there is no difference in the yield of an ILR in patients presenting with or without syncope.