An Ohio State University Wexner Medical Center research team discovered that between 46 percent and 86 percent of health alerts sent by their patients' implantable Medtronic heart monitors were false positives, StarTribune reports.
A group of nurses at the Columbus-based medical center who scan transmissions of cardiac patients every day for issues like atrial fibrillation noticed that some data coming in from patients with a Medtronic Reveal Linq implantable loop recorder was not accurate, according to the report. OSU performed an analysis of the device and published results of the study in Heart Rhythm journal last month, the publication reports.
After analyzing data on 559 consecutive Ohio State patients, researchers found that 86 percent of all 78 transmissions in cryptogenic stroke patients were false positives, and 71 percent of syncope patients' and 46 percent of Afib patients' were false positives. During the four-week study period, 15 patients were also accurately diagnosed with Afib, according to the report.
Medtronic's Linq device is designed to monitor irregular heartbeats continuously for a minimum of three years. The devices are intentionally developed at high sensitivity because they are designed to search for evidence that goes undetected by other diagnostic methods and tools, a Medtronic spokesperson told StarTribune.
"We are trying to err on [the side of] sensitivity, because of the severity of the patient illness," said Robert Kowal, MD, Medtronic's cardiac rhythm and heart failure division CMO, according to the report. "With all these tests, you are trading sensitivity and specificity all the time. The good news with Linq is, we will continue to improve the algorithms, and also give the physician the ability to adjust those as it fits their patient needs."
Medtronic has been working with the OSU clinicians since the study was performed to develop ways to reduce the number of false positives made by the devices. One initiative the organizations have taken is custom programming, which consists of programming the implantable device for only specific clinical information and turning off the data for information that is not needed.