A wave of innovations can prevent devastating illness—and overwhelm cardiologists at the same time.

Personal technology is propelling a new age of cardiovascular medicine. From smartphone apps to wearable and implantable devices, this burgeoning technology can capture real-time information about a patient’s heart health and in some cases trigger them to seek medical treatment even if they aren’t experiencing symptoms.

“Detecting what a patient doesn’t perceive launches us into a new area of medicine,” says Dr. Emile Daoud, a cardiologist at the Ohio State University Wexner Medical Center.

Monitoring technology falls into two categories: wearable, such as watches and phone apps; and implantable, such as tiny devices implanted just under the skin, or in an artery, for example. Their uses are many—from tracking steps, blood pressure and weight, to monitoring heart rhythms and fluid pressure. Some use interactive messaging to connect patients and healthcare providers.

Constant monitoring can have key implications in preventing serious events, such as stroke or heart attacks, physicians say. For example, atrial fibrillation, or Afib, is a heart rhythm abnormality that often goes undetected but is a leading cause of stroke, resulting in some 130,000 deaths and 750,000 hospitalizations a year in the U.S., according to the Centers for Disease Control and Prevention. Devices that remain with a patient continuously have an edge over those worn for a finite period, when an arrhythmia may not occur, experts say. “You’re trying to capture something in a pretty tiny window of time,” Daoud says.

Cardiologists have mixed feelings about this expanding technology. “It provides extremely valuable data, if we can get our arms around it,” says Dr. Joshua Silverstein, a cardiologist with Mount Carmel Health. “It can prevent catastrophic events like stroke. … It’s about getting answers for patients, and getting to the bottom of their condition.”

At the same time, he and other heart specialists fear what they see as a bombardment of data that must be reviewed and acted upon. Silverstein says that to deal with the influx of data, “you need to have a really organized process. Larger medical centers have device clinics, where that’s all the staff does.” Even with the infrastructure that comes with a larger system, the ever-increasing amounts of incoming data are daunting, he says. “We are overwhelmed.”

At OhioHealth, “We’re creating a process for reviewing all this data in a timely manner. Most likely it will involve creating a separate data stream on the order of, does your smart watch need a second opinion?” says cardiologist Dr. Anish Amin.

Despite physicians’ trepidations about the volume of data generated by wearable and implantable technology, there is no turning back, Silverstein says. “You can’t avoid this, it’s coming. Now that Apple has it, it’s going to explode.”

In September, the FDA gave clearance to an Apple Watch with electrocardiogram apps designed to detect irregular heart rhythms that the wearer might not notice or that might not show up during a routine medical exam. The watch also has an app that senses if someone has experienced a hard fall.

Apple also is involved in a clinical trial to determine whether a mobile app that uses the optical sensor on the Apple Watch to analyze pulse rate data can identify atrial fibrillation as well. 

A sampling of other personal technology available or being tested includes:

AliveCor KardiaBand replaces an Apple Watch band with one that detects heart rate and physical activity. When it sees something it doesn’t expect, it sends a notification to take an electrocardiogram to measure heart rhythm. AliveCor KardiaMobile works with smart phones and uses finger pad sensors to obtain an electrocardiogram. The Cardiio app uses a smart phone camera to detect heart rate based on changes in light reflected from the face or fingers. Developed by the Massachusetts Institute of Technology Media Lab, it does not have FDA approval, and like several other apps, comes with disclaimers that it is not intended for use in people who already have a heart condition, nor is it a substitute for medical care. Abbott CardioMEMS is designed for heart failure patients to detect changes in the pressure of blood through the pulmonary artery, which can indicate the condition is worsening. The implanted device sends information wirelessly to physicians, who can then adjust medications and treatment if necessary. Rose Chumita, a nurse at Ohio State University’s Wexner Medical Center, along with a software engineering team in the OSU’s Department of Biomedical Informatics, created an app for previously hospitalized heart patients so that they can more easily participate in follow-up care after their rehabilitation. Users input blood pressure readings and weight, as well as fluid and sodium intake throughout the day. The app warns users when their numbers fluctuate too high or low and gives immediate feedback and suggestions.

Other apps help plan heart-healthy meals, assess risk for cardiovascular disease caused by atherosclerosis (hardening of the arteries) and monitor glucose levels, for example.

Getting ahead of cardiac problems has the potential to save healthcare dollars. The economic component looms large in conditions such as heart failure, where reimbursement may be denied if a patient is re-admitted to the hospital within a specified number of days after being discharged.

At the same time, the devices have limitations. Most use algorithms in lieu of an actual reading, which can lead to errors. What some sensors think is Afib often is not. “The key is, you need someone to interpret these. And physicians need to be paid to do this,” Silverstein says.

OSU’s Daoud agrees. “Technology may be ahead of the medical algorithm to manage it. It is certainly ahead of medical personnel’s ability to manage it.” For example, it’s possible that doctors will have to wrestle with the issue of whether to put a patient on anticoagulant therapy–usually a lifelong proposition—with increasing frequency.

Amin says while it’s possible to pack a tremendous amount of analytics into a small implantable, the tools to manage effectively that information don’t yet exist in heart and vascular care.

For example, technology to track progress after a “fixed encounter” such as knee replacement surgery relies on recovery and rehabilitation following a certain trajectory.

“For chronic diseases, the models are much more difficult to build. Zero clinical pathways have been developed,” Amin says. “We need larger scale studies to prove that any of this stuff works in real life.”