Clinical News: Diagnosing Elusive Arrhythmias
Remote cardiac monitoring technology provides data in real time.
Remote patient monitoring systems are networked communication solutions that allow for exchange of digitized data from implanted or wearable devices. For cardiac patients, data can include ECG recordings and continuously updated information. Remote monitoring for cardiac patients with an irregular heartbeat has been shown to decrease the need for office visits and provide earlier detection and management of arrhythmic events.
Many key technological breakthroughs have paved the way for these devices, including the digitization of the ECG signal, the miniaturization of electronic components, and wireless communication. The advance of this technology represents the first time important health care decisions can be made without having the patient and caregiver in the same room.
For patients outside the hospital or clinic with cardiac rhythm disturbances who would benefit from technology that can record and/or transmit data, there are several ambulatory ECG systems from which to choose. The choice among these options typically is made based on the anticipated duration of time required to capture a potential cardiac rhythm problem. Holter monitors can record seven to 48 hours of activity, while event monitors can capture two to four hours of activity. Insertable loop recorders can record for up to three years. For those with daily symptoms, a Holter monitor may suffice. If issues occur weekly or monthly, an event monitor may be chosen. For those with less frequent symptoms, an insertable loop recorder that can self-activate and retain information for later download is an excellent option.
The Need for Remote Rhythm Monitoring
Atrial fibrillation—the most common type of abnormal heart rhythm—affects as many as 6.1 million people in the United States alone, and many of those patients may require remote rhythm monitoring. Symptoms of arrhythmias can be difficult to capture with noncontinuous systems. If undetected, some arrhythmias can lead to serious complications, including stroke, cardiac arrest, and sudden death.
There's also the challenge of motivating patients with traditional implanted devices to come to a scheduled office visit for data downloading. One study showed that of almost 40,000 patients who received a cardiovascular implantable electronic device with ECG event recording capabilities, roughly 42% came to an initial visit within two to 12 weeks after implantation, but 22% didn't make even one follow-up visit within the first year.
A study by Berg Insight, a global market research provider based in Sweden, found that an estimated 7.1 million people were remotely monitored as part of their health care as of 2016, and the number of patients remotely monitored by physicians increased about 44% between 2015 and 2016. Interestingly, the researchers found that in addition to cardiac rhythm monitoring and sleep therapy devices, remote monitoring systems to measure glucose levels in diabetes and medication adherence also are becoming popular.
Benefits of Remote Patient Monitoring
With the Confirm Rx system, the first and only smartphone-compatible insertable cardiac monitor, patients can record symptomatic events in real time from their own smartphones without the need for additional hardware such as handheld activators or bedside transmitters. Also, patients are not required to record symptoms to have data about abnormally detected events automatically sent to their physicians, but can, if they choose.
The system automatically informs patients of successful device checks and data transmission, making it easy for medical staff to review transmitted data. Confirm Rx allows patients to stay connected to their physician remotely and engaged in their care.
Available Cardiac Monitoring Devices
• the Holter monitor, with 24- or 48-hour, or 7- to 14-day ECG recording;
• telemetry patches that typically provide data for up to 14 days;
• external or insertable loop recorders; and
• therapeutic cardiovascular implantable electronic devices, such as pacemakers, including cardiac resynchronization therapy and implantable cardioverter-defibrillators.
Deciding What's Best for a Particular Patient
Confirm Rx is the thinnest device, easy to implant with minimal scarring—requiring only local anesthetic, no sutures, just Steri-Strips—and provides continuous monitoring without the need to be close to a transmitter. The continuous loop recorder that transmits data by smartphone helps ensure all the information is captured and reported. Confirm Rx is covered by Medicare and other payers, and mobile transmitters are available for patients who don't have a compatible smartphone device.
The key to deciding what's best for the patient is to be certain the necessary data will be transmitted. Patients who may benefit most from a device such as Confirm Rx are those who occasionally feel their hearts racing, although it also represents an important diagnostic tool for those with intermittent syncope or other symptoms.
Frequently, a physician will tell a patient, "Maybe it's paroxysmal atrial tachycardia and you don't have to worry." But a physician or health care practitioner may not be certain. It could be atrial fibrillation. For any patient who's been diagnosed with a rapid heart rate in the upper chambers of heart, which is called supraventricular tachycardia, failing to identify the actual heart rhythm can be dangerous.
Devices such as Confirm Rx allow the data to be automatically transmitted by smartphone to the cardiologist's office for review and analysis. If there is a problem that requires follow-up, the patients will be called. A patient is usually asked to schedule an appointment only if there's clinically actionable data that require an in-person evaluation.
One Patient's Story
Kate had the Confirm Rx device implanted, and, about two weeks later, sitting at a hair salon, she began to feel her heart beating quickly. She pushed the one-touch record function on her phone, which captured the episode. It was atrial tachycardia. Kate says she likes the device, both for the reassurance it provides that any problems are likely to be detected and diagnosed quickly because it allows her to be fully engaged in her health care.
Downsides of Continuous Monitoring
A study of patients using an older cardiac monitoring system showed that only 64% were enrolled in an online system that monitors patients implanted with the cardiac devices. Of those, 88% transmit their device data less than once a year. Other monitoring systems show even less transmittal of patient data, according to the research. Just 69% of patients using another older remote monitoring program transmit more than once a year. Moreover, most patients in the United States don't have their system's fibrillation alerts turned on.
Getting patients involved with data management is typically difficult. For example, Holter monitors—if used for long periods of time—restrict a patient's ability to travel, as they would need to bring along the corresponding bulky transmitter and reader. The Confirm Rx mobile phone app, called myMerlin, allows patients to record symptomatic events in real time from their own smartphones without the need for additional hardware such as handheld activators or bedside transmitters. As a result, the system ensures that patients can activate the system easily using their cell phones before they leave the hospital.
Analyzing the Transmitted Data
Managing the transmittal of data to a practice is not difficult and can be cost effective. Creating a good system that involves skilled nurses, nurse practitioners, or device techs to review the data daily and refer them to the physicians to analyze is critical. The information is billable.
It's important to help patients understand how their systems work. You should explain that there are some limitations. For example, patients should know that the physician doesn't routinely act on data on the weekends and that they should call 911 if they ever experience any serious symptoms or discomfort. You should also explain that you don't need to set up routine appointments, but rather will see them if there is a problem. Despite these limitations, in my clinical experience I have seen the system significantly improve the quality of life of patients.
Data are securely transmitted from the device to the patient's physician via the myMerlin mobile app on a schedule set by the physician or clinic. The transmissions are sent to the Merlin.net Patient Care Network, which provides clinicians with data and reports.
Enhancing Our Knowledge Base
These devices should help reveal the long-term treatment response to medications. Most of what is known is based on event monitors, which cannot capture the complete story. It's further thought that adherence to prescribed medications will improve as patients see the day-to-day impact on their heart rhythm response.
These advances in remote cardiac monitoring also should shed light on the benefits of prevention, such as the impact of exercise and lifestyle modifications, including stress management, weight loss, sleep apnea, and activities such as walking, running, and yoga.
The new remote cardiac monitoring devices should make it possible to conduct randomized clinical trials to better assess their benefits. Critics have said there's an absence of randomized trials for remote monitoring, and that's true. One trial is looking at the recurrence of atrial fibrillation after cardioversion using loop recorders to monitor patients, which will provide more clinically relevant data, help us treat patients faster and sooner, and improve overall health.
The Future of Remote Monitoring
It's likely we will be able to share data across remote devices, cloud-based services, and apps. It will be easier than ever to conduct clinical trials to measure responses not just to medications but also to lifestyle changes and stress.
We will need to find ways to transfer what we learn from the vast amount of data that will be available to us to create personalized treatments and therapies that consider not just an aberrant heart rhythm but also a patient's complete medical history and other health issues. Remote monitoring technology will accomplish these goals seamlessly, without putting the burden on the patient and while providing cost savings to the health care system.
— Harish Manyam, MD, is the director of cardiovascular research and the head of the Atrial Fibrillation Center at Erlanger Cardiology in Chattanooga, Tennessee.