(This Dec.23 story adds dropped letter to Marc, in the 13th paragraph)

By Linda Carroll

(Reuters Health) – The system in place to monitor safety of medical devices in the United States may not catch failures soon enough to prevent serious harm to patients, a study suggests.

Researchers examined data on a heart pacemaker that was eventually recalled by its maker and found that numerous people were harmed in the 19 months that passed after the first reported device failure, according to the study in JAMA Internal Medicine.

At the researchers’ own institution, five patients suffered fainting episodes, four also experienced difficulty breathing. And in reviewing records from the U.S. Food and Drug Administration (FDA) MAUDE database, the researchers located another 19 patients who suffered serious adverse effects when their pacemakers failed: One died, two suffered cardiac arrest, eight had fainting episodes, two experienced lightheadedness and dizziness, and eight suffered heart failure, difficulty breathing and weakness.

Two problems prompted the recall of the devices: battery failure and loose wiring. On top of these, the devices could malfunction when doctors communicated with or programmed them, something the company never mentioned in its updates, the researchers note.

According to the FDA database, another 38 patients suffered adverse events even after the recall was issued in 2015.

“The heart failure pacemaker recall was unnecessarily delayed and did not include all the critical information needed for patient management,” senior study author Dr. Robert Hauser, a cardiologist from the Minneapolis Heart Institute, and his colleagues write. “We believe these deficiencies negatively affected the outcomes in patents at MHI and those represented in the FDA MAUDE database. These findings should prompt reforms in how the medical device industry and the FDA conduct medical device surveillance and manage future recalls.”

The authors did not respond to a request for comments.

Although the devices could shut off unexpectedly because of battery failure, the FDA classified the recall as class II, “meaning the device could cause temporary or medically reversible health consequences but the probability of serious adverse health consequences was remote,” Hauser and his team write.

To take a closer look at adverse events related to the pacemaker recall, the researchers examined the records of 448 patients at MHI who had received this model of pacemaker between 2003 and 2011, including 70 who were pacemaker dependent, meaning they could die if the pacemaker stopped working. They also looked at the FDA’s MAUDE database, where they determined that 205 devices had been returned to the manufacturer between November 2008 and January 2019. Of those, 158 had stopped working because of a battery failure – including 8 failures that occurred during programming or telemetry – and 35 had stopped working because of a loose wire.

Dr. Charles Love isn’t convinced that the system isn’t working. What’s obvious when you look back on data may not have been so clear at the time, he said.

“Retrospectively, you can say ‘here is the first day the device first failed and it took 19 months until everyone was notified,'” said Love, a professor and director of cardiac rhythm device services at Johns Hopkins Medicine in Baltimore, Maryland.

But when devices start coming back to their makers, the companies need to figure out what went wrong. Sometimes that can take a while, Love said. “Once they’ve identified an issue that is beyond random component failure and once they know what the mechanism is, then they need to correct it and notify everyone.”

The new report underscores the need for patients with pacemakers “to maintain close follow-up with the physician who manages their device,” said Dr. Marc Miller, a cardiac electrophysiologist at The Mount Sinai Hospital in New York City. “As shown in this study, while the overwhelming majority of pacemakers will never malfunction, a very small percentage of devices can fail. Being proactive can prevent complications.”

The findings do suggest problems with the device monitoring system, he said.

The fact that the manufacturer was aware of battery failures at least 1.5 years before an advisory was communicated, a time frame in which patients experienced complications resulting in harm, was indicative of an industry-wide systems failure,” Miller said.

SOURCE: https://bit.ly/2ZbGc0S and https://bit.ly/2PHActr JAMA Internal Medicine, online December 20, 2019.