Ramakrishna Mukkamala, PhD (pictured), McGowan affiliated faculty, recently participated in a panel discussion on the ineffectiveness of cuffless blood pressure monitors for Medscape’s Perspectives.
Dr. Mukkamala was joined by Jagmeet P. Singh, MD, from Medscape Cardiology, and George S. Stergiou, MD, from the University of Athens.
The panel noted that cuff-based blood pressure monitoring has, to date, been the basis for successfully treating people with high blood pressure and for treating disease. However, because blood pressure is a continuous phenomenon, cuff-based devices provide limited information, as they cannot be used to assess continuous blood pressure behavior.
The shortcomings of cuff-based devices led to numerous cuffless innovations that now have regulatory clearance, including those that operate on pulse wave analysis and pulse arrival time. “Pulse wave analysis involves measuring a peripheral arterial waveform,” stated Dr. Mukkamala, “usually using an optical sensor or a force sensor, and then extracting features from the waveform using machine learning and calibrating the features to blood pressure values.”
Dr. Mukkamala continued, “Pulse arrival time methods work in conjunction with pulse wave analysis methods. Pulse arrival time methods also record the electrocardiogram. They will also extract features from that signal and the arterial waveform.” These features are then calibrated to blood pressure values, and the calibration is assisted by cuff-based devices.
However, Drs. Mukkamala and Stergiou cited recent findings by Microsoft Research’s Aurora Project claiming that cuffless devices, such as those on smartwatches, phones, or other portable devices, currently “offer zero value.”
That said, the panelists believe that cuffless devices do have the potential to add value to patient care in the future. Dr. Mukkamala stated that having “a standard to validate cuffless devices would be important, so that the regulatory bodies could adopt it and that’s how they could clear devices. It would prevent inadequate devices from being used for clinical purposes.”
In terms of the technology, he maintained the importance of looking at different approaches. “Maybe taking inspiration from how automatic cuffs work,” he said. “Maybe targeting the aorta. Most of these devices target small vessels, they have smooth muscle, and that causes many technical problems. The aorta is more elastic and it’s hard to get convenient measurements from it.”
Towards the end of the panel discussion, Dr. Mukkamala offered words of advice for clinicians and engineers, noting, “I think there are many studies in the literature, and many of them on the same tack — this pulse wave analysis and pulse arrival time. Many of them will report that those methods work well. In most instances, they’re actually misleading. I would say, don’t take these papers at face value. We have to look at them critically and then conclude whether we think that the data show these devices work well or not.”
Having a standard by which to measure every cuffless device would go a long way towards their reliability. In short, as Dr. Stergiou stated, cuffless devices have to “serve the science.” By innovating reliable and accurate cuffless strategies, the ultimate goal is to provide better patient care.
Watch or read the transcript of the full panel discussion on Medscape here