Cardiac Telemetry

Cardiac Telemetry

Telemetry rhythm surveillance is standard of care for a large subgroup of hospitalized cardiac patients. Indications for telemetry vary throughout spectra of risks, from direct detection of a life threatening arrhythmia, to determination of a rhythm or conduction disorder, to observation of heart frequency when tailoring treatment. Saturation, activity levels and temperature for example are not noted. Duration and indication leave much room for variety in usage.

Telemetry surveillance utilizes multi lead electrocardiography (ECG) recording and electrodes attached to stickers on the thorax are used. A wearable pouch is often used to carry the data device, often in an embodiment that resembles a first generation walkman. The patients are thus attached to wires and carry a pouch, and are thereby limited in movements, dressing and showering for example. Electrodes often detach, due to patient restlessness, unease with the cables and stickers at night, a sweaty skin, or other causes. Patients often ask for telemetry to be removed due to interference with activities. Due to the hindrance of monitoring, the time needed for electrode repositioning and others, telemetry is a diagnostic strategy for a subset of patients, for a limited amount of time, and limited to patients still being hospitalized. Commonly, ECG recordings of telemetry can be uploaded to the electronic health record (EHR), like a PDF file, but not the data like pulse rate itself.


Holter ECG

While Holter ECGs have improved over the past years and now provide an ECG up to several weeks, Holter devices can feel uncomfortable to patients, especially with multiple sticker electrodes attached to the body. The downside of these devices and the reason why most of them are not worn more than 3-5 days, is the need for sticker electrodes [1]. In routine care, skin reactions to the electrodes are a frequent problem. Sticker dislocation is a prevalent problem.

The 24h-Holter ECG technology has only 20-25% diagnostic yield [2]. Single-lead patch-based ambulatory external ECG devices have a higher yield to diagnose AF. These patches enable continuous long-term monitoring outside of the hospital and can be used for up to a month; however, in many instances, monitoring is terminated after just 1-2 weeks.

Impact of study duration on detection of AF in patients undergoing ambulatory external ECG monitoring was studied [3] and the first occurrence of AF would have been missed in 10%-32% of the patient population during a 14-day monitoring study, depending on the minimum AF episode duration. First AF detections that occurred after 14 days were most common for patients with diagnosis code of AF, but also occurred for patients with a diagnosis code of palpitations, syncope and stroke. Additionally, many patients were observed to have different AF burden in the monitoring days 1-14 and 15-28, which may have implications for diagnosis and treatment. These results establish the importance of monitoring beyond 14 days.

Patients with AF yet to present

Impact of study duration on detection of AF in patients undergoing ambulatory external ECG monitoring [3]

In addition, medical monitoring devices may lead to stigmatization of patients, thereby not motivating users to wear it consistently, which is critical to obtaining adequate measurements.

Cardiovascular monitoring technologies like the Holter systems are attached and removed from the patient in the health care institution, which is an inefficient and labour-intensive process.

Moreover, the analysis of ECG data by medical specialists, delays the time between measurement and diagnosis.

 Lastly, patients face long waiting lists for Holter monitoring due to shortage of Holter devices in health care institutions.


  1. ‘Holter Monitor’,
  2. Boriani G, et al., Asymptomatic atrial fibrillation: clinical correlates, management and outcomes in the EORP-AF Pilot General Registry. Am J Med. 2014 Dec 19.
  3. Impact of study duration on detection of atrial fibrillation in patients undergoing ambulatory external ECG monitoring. Mehta, P., Teplitzky, B., McRoberts, M., Mittal, S., Heart Rhythm Journal, Vol. 16(5), S1 – S712, S‐PO02‐195.