Investigating palpitations: the role of Holter monitoring and loop recordersBMJ 2017; 358 doi: https://doi.org/10.1136/bmj.j3123 (Published 27 July 2017) Cite this as: BMJ 2017;358:j3123
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We read with interest the education article by Abi Khalil et al in last week's issue “Investigating palpitations: the role of Holter monitoring and loop recorders” . We agree with the authors that ambulatory monitoring in an outpatient setting is an important element of investigating palpitations.
The authors state "personal mobile technology" as a recent development for external loop monitoring, stating that "immediate interpretation is possible using an application downloaded from the internet." We presume the authors refer to the AliveCor ECG monitor system. The NICE guidance regarding the CE-marked AliveCor ECG monitor and AliveECG software application states that " in built software notifies the patient if their reading is normal or if AF has been detected due to an irregularity in the reading. " 
To our knowledge, The AliveCor ECG/Alive ECG system is only approved to make automatic arrhythmia interpretations of atrial fibrillation. Any other arrhythmia is diagnosed manually by sharing with an appropriately qualified medical professional, and so strictly speaking, it would not be correct to state that "immediate interpretation" is possible via the (software) application. However, patients do share these opportunistic ECG recordings during outpatient consultations.
Furthermore, in such an age of telemedicine, we believe the authors and BMJ readers alike would share our enthusiasm for the latest generation of wearable ECG patch monitors for 7 or 14-day extended arrhythmia monitoring . These newer devices attach to the chest via a self-contained adhesive strip and event recorder without the encumbrances of chest leads or ECG electrodes of conventional Holter monitors.
These "set and forget" monitors can be attached with minimal training in the outpatient clinic at the time the decision is made. The device is posted by the patient after its removal. Thus these new devices form an integral component of a true one-stop service saving at least two hospital visits. This in turn frees up the resources of the cardiac physiology department. Similarly these wearable ECG patch monitors do not require operating theatre resources of implantable loop recorders.
In our clinic and research trial experience , these ECG patch monitors are well-tolerated, record a high quality signal, and capture a cardiac data set on the order of one million beats of information for arrhythmia analysis. This compares favourably to a data set of 80,000 - 100,000 beats from a typical 24-hour Holter monitor.
Dr Robin Chung, NIHR BRC cardio-oncology fellow
Dr J Malcolm Walker, consultant cardiologist
The Hatter Cardiovascular Institute
University College London
London WC1E 6HX
Declarations: Dr Chung serves as a social media editor for the journal Heart Asia BMJ.
 Abi-Khalil C, Haddad F, Al Suwaidi J. Investigating palpitations: the role of Holter monitoring and loop recorders. BMJ 2017; 358: j3123.
 AliveCor Heart Monitor and AliveECG app (Kardia Mobile) for detecting atrial fibrillation. MedTech Innovation Briefing (MIB 35) published August 2015. https://www.nice.org.uk/advice/mib35/chapter/technology-overview. accessed 31 July 2017.
 Comparison of continuous sternal ECG patch monitors (Carnation and Zio) trial. Clinicaltrials reference NCT02031484 https://clinicaltrials.gov/ct2/show/NCT02031484 accessed 03 August 2017.
 Chung R, Maulik A, Hamarneh A, Hochhauser D, Hausenloy DJ, Walker JM, Yellon DM. Effect of Remote Ischaemic Conditioning in Oncology Patients Undergoing Chemotherapy: Rationale and Design of the ERIC-ONC Study. Clin Cardiol 2016; 39(2): 72-82.
Competing interests: No competing interests