A loop implant, also known as an insertable cardiac monitor (ICM) or implantable loop recorder (ILR), is a small medical device designed to continuously record a person’s heart rhythm. This technology helps healthcare providers understand heart activity over extended periods when symptoms are infrequent or difficult to capture with shorter-term monitoring.
The Loop Implant Defined
A loop implant is a compact, wirelessly enabled device, often compared in size to a USB stick or a AAA battery. Its primary function is to continuously monitor and record the heart’s electrical activity, providing long-term data for diagnostic purposes. Unlike external monitors, a loop implant can record heart rhythms for up to three years, with some models lasting six years.
This device is useful for detecting heart rhythm abnormalities, known as arrhythmias, that occur sporadically and are missed by brief electrocardiogram (ECG) tests. Healthcare providers use loop implants to identify causes of unexplained fainting spells (syncope), recurring heart palpitations, very fast or slow heartbeats, and to assess stroke risk related to conditions like atrial fibrillation. This helps determine if symptoms are linked to an underlying heart condition, enabling appropriate treatment.
How the Device Functions
The loop implant continuously senses and records the heart’s electrical signals. It features internal components like a small battery and recording memory to store this data. The device automatically detects and saves recordings of abnormal heart rhythms, including various types of bradycardia (slow heart rates) and tachycardia (fast heart rates), such as supraventricular tachycardia and ventricular tachycardia, as well as atrial fibrillation.
In addition to automatic recordings, patients can manually activate the device to save a recording if they experience symptoms like palpitations or dizziness. This manual activation captures the heart’s activity at that moment, and it can also access and record data from the preceding minutes, even if the symptom has already passed. This dual capability ensures both symptomatic and asymptomatic arrhythmias are documented, providing a complete picture of the heart’s electrical behavior.
Implantation and Data Collection
Implanting a loop device is a minor outpatient procedure performed in a clinic or hospital setting. It takes about 15 to 20 minutes and involves local anesthetic to numb the area, ensuring the patient remains comfortable and awake. A healthcare provider makes a small incision, typically on the upper left side of the chest, and creates a small pocket just beneath the skin to insert the device.
After the device is in place, the incision is closed with stitches or surgical glue. Once implanted, the loop monitor collects heart data, which is then transmitted to healthcare providers. Transmission occurs automatically through a bedside home monitor that sends information wirelessly while the patient sleeps, or via a smartphone application that syncs with the device. This remote monitoring allows clinicians to review recordings and identify significant heart rhythm events.
Life with a Loop Implant
Living with a loop implant involves minimal disruption to daily activities. The device is inconspicuous and allows individuals to resume most normal routines, including showering, bathing, and exercising. Patients receive a manual with specific guidelines and should follow instructions from their healthcare provider, especially regarding incision care during the initial healing period. While the device is compatible with common household electronics, patients should inform medical and dental personnel about their implant before any procedures, including an MRI.
The duration for which a loop implant remains in place varies, ranging from two to six years, depending on the model and diagnostic needs. The device is removed once a diagnosis is made or the monitoring period is complete. The removal process is a minor outpatient procedure, similar to implantation, involving a small incision and local anesthetic.