Remote Patient Monitoring for Heart Failure Grows More Sophisticated

Despite its promise to improve health outcomes, remote patient monitoring (RPM) has so far failed to see as much adoption as some providers had hoped, in part due to reimbursement restrictions. But CMS is gradually lowering those barriers as research suggests that RPM can serve to reduce the number of hospitalizations, readmissions and lengths of stay in hospitals for certain chronic conditions.

I had the chance last week to interview Akshay Desai, M.D., associate director of Brigham Cardiovascular Consultants and an assistant professor at Harvard Medical School, about the evolution of RPM at the 793-bed Brigham and Women’s Hospital in Boston in the care of heart failure patients. The hospital has started using an implanted device called the CardioMEMS HF System, which regularly transmits valuable data to the heart failure clinical team. Brigham and Women’s also has started using the Merlin.net Patient Care Network portal, which correlates rhythm data from St. Jude Medical’s implanted devices with pulmonary artery pressure readings from the CardioMEMS HF system.

Desai noted that many heart failure programs have telemonitoring programs in place. Most are focused on patients’ daily measurement of weight, with the notion that if weight changes rapidly in the short term, that is probably a fluid-related gain and can be adjusted with a change in diuretics. “That works pretty well in the short term,” he said. “The trouble is, all of us have fluctuations in weight over longer time intervals, so more gradual changes are less informative, and there are confounding factors in heart failure patients. As they get worse, they eat less so therefore may lose lean body mass and replace that with fluid. So weight may not change, while heart failure is getting worse. So telemonitoring is OK as a short-term surrogate, but not a great long-term surrogate for changes in filling pressure. It is kind of an insensitive signal for detecting heart failure decompensation.”

He added that although most hospitals have such programs, in systemized studies, it has been hard to show that telemonitoring of vital signs and symptoms, in and of itself, reduces the incidence of hospitalizations. That is in part because telemonitoring rarely exists in isolation. Heart failure management programs are comprehensive and include specialty nurse follow-up among other features.

But the type of monitoring Brigham and Women’s has started has more potential, he said, because it offers a regular direct measure of what cardiologists have been trying to get through indirect surrogates. “The best measure of fluid status is filling pressure, because as volume increases in the heart, so does pressure,” he explained. “So if we know what normal reference pressures are for any given patient, if there is enough deviation in the pressure, that is an actionable signal and we can change it. It responds fairly rapidly to standard interventions like diuretics and we can gauge the efficacy of our therapy on demand.”

Here is how it works: A patient with Class III heart failure struggling with managing their condition gets a CardioMEMS device implanted and their filling pressures are measures. The device is calibrated and targets are established with regard to the pulmonary artery diastolic pressure.  The system is activated by an antenna in a pillow the patient lies down on each day at home. The patient pushes a button to activate a reading. “Over time, on a weekly basis, and sometimes more frequently than that, we monitor the pressures in all the implanted patients,” Desai explained, “and if we note pressures are outside the target range and particularly if they are trending in the wrong direction, then we intervene to treat those pressures with adjustment to medication therapy. Then we reinvestigate after the change in therapy to see if we have had the desired change in pressure. If not, we can further modify the therapy. If the pressures are back in range, we may back down and restore the previous medication dosing. So there is a very efficient feedback loop with the patient.”

The system can be programmed in a number of ways, including automated alerts. When they get e-mail alerts, clinicians can log into the portal via a link contained in the e-mail, pull up pressures for the patient and see trends in pressure over time and make a decision about whether to intervene.

Although his organization has only been using it for a few weeks, Desai said the online Merlin platform would eventually allow for integration on the back end with the hospital’s EHR. “There is the potential to leverage the online platform to populate the patient record to facilitate the documentation of what we are doing through remote monitoring.” There are also billing reminders built in to collect reimbursement available for routine remote patient monitoring.

Desai said the key to the system is that it helps identify when patients are getting in trouble, allows clinicians to make a change, see that the change has an impact, and restore equilibrium. Not every patient will respond the way you would like, he admitted. “But the real promise of longitudinal pressure monitoring is it allows for early detection of patients getting into trouble and the opportunity to intervene at an early sign of decompensation before it is so severe they have to be hospitalized.”