Letter from the Editor in Chief

DOI: 10.19102/icrm.2014.051101

Moussa Mansour, MD, FHRS, FACC

Dear Readers,

Among the many interesting articles in this issue of the Journal, I would like to bring to your attention the paper by Dr. Eisenberg and his colleagues entitled “Chronic Ambulatory Monitoring: Results of a Large Single-Center Experience”. The authors evaluated the diagnostic yield of a wearable cardiac monitoring device. They reviewed data from 524 patients who were prescribed the monitor for a variety of indications including monitoring for atrial fibrillation and elucidating the mechanism of palpitations. This study resulted in many interesting findings the most important of which in my opinion is that the majority of atrial fibrillation episodes detected by the long-term monitoring device were asymptomatic.

The results of this study came few months after the publication of two landmark studies in June of this year, EMBRACE and CRYSTAL AF. Both of these studies demonstrated that in patients with cryptogenic strokes, prolonged monitoring with external ambulatory monitoring or implantable recording devices significantly improved the detection of atrial fibrillation compared to the standard practice of short-term monitoring. It has been suspected for long time that patients with atrial fibrillation have frequent asymptomatic episodes. This suspicion was confirmed by the findings of the EMBRACE and CRYSTAL AF studies, in addition to the study by Eisenberg et al, and other studies describing the occurrence of asymptomatic atrial fibrillation in patients with pacemakers.

Prolonged cardiac monitoring clearly has a beneficial role in patients with palpitations of unknown origin as well as in patients with cryptogenic stroke. In addition, I believe that prolonged monitoring may also have an important role in monitoring patients after ablation for atrial fibrillation. Most of the studies describing the outcome of ablation for atrial fibrillation relied on symptomatic recurrence to gauge the success rate of the procedure. Many ablation studies used 24-holter monitoring or symptomatic triggering of cardiac monitors to record recurrences. It is likely that these methods of monitoring underestimate the recurrence of atrial fibrillation after catheter ablation. While most ablations for atrial fibrillation are performed to eliminate the symptoms of this disease, I believe that it is important to quantify the burden of asymptomatic arrhythmia after ablation in order to prevent strokes in patients who are considered for cessation of anticoagulation after ablation. Also asymptomatic recurrence can lead to tachycardia-mediated cardiomyopathy and detecting the arrhythmia can help prevent this complication.

At our center, the standard monitoring strategy after ablation for atrial fibrillation consisted until recently of 30-day monitoring at 3, 6, and 12 months after ablation. However with the introduction of the miniaturized implantable loop recorder, an increasing number of the patients are being monitoring using this technology. The small size of the monitor, the long battery life, and the ability to record asymptomatic episodes of atrial fibrillation make it a powerful tool for post ablation monitoring.

Prolonged monitoring necessitates the use of advanced technology that can be expensive. This comes at a time of increasing demands by hospitals and payers to reduce healthcare expenditure. As a result it is crucial for the scientific community to strive for the publication of studies demonstrating the potential saving in cost and suffering with the use of advanced monitoring technologies that can help detect asymptomatic atrial fibrillation and treat this disease before the occurrence of complications.

As always, I hope that you find this issue of the Journal beneficial to you and your practice. Best wishes for a Happy Thanksgiving.

Warm regards,

Moussa Mansour, MD, FHRS, FACC
Editor-in-Chief
The Journal of Innovations in Cardiac Rhythm Management
MMansour@InnovationsInCRM.com
Director, Cardiac Electrophysiology Laboratory
Director, Atrial Fibrillation Program
Massachusetts General Hospital
Boston, MA