In at least two cases, iRhythm did not report patient deaths in the required 30-day window, and instead reported them the following year, the FDA said.
The FDA issued the warning letter on May 25, 2023, following an inspection of the company’s facility in Cypress, California, in July and August 2022. The alleged violations concern iRhythm’s Zio AT electrocardiogram (ECG) monitoring system, which includes the Zeus software reporting system. The FDA cleared the system in 2017 under the 510(k) pathway.
Previously: iRhythm faces another subpoena from the DOJ
While the FDA said some of iRhythm’s responses and corrective actions have been adequate, the agency had a lengthy list of action items for the company.
“Your firm should take prompt action to address any violations identified in this letter,” the agency said. “Failure to adequately address this matter may result in regulatory action being initiated by the FDA without further notice. These actions include, but are not limited to, seizure, injunction, and civil money penalties.”
iRhythm disclosed the warning letter and some of its allegations last month.
“iRhythm takes these matters very seriously and intends to respond within the specified time period and work diligently to address the FDA’s comments,” the company said in an email to MassDevice today. “iRhythm maintains a commitment to a culture of quality and integrity. … iRhythm has already taken action intended to address certain items identified by the FDA in their [Form] 483 observations and intends to take appropriate action to further address the items identified in the 483 observations and the warning letter.”
Unapproved device violations
The FDA said iRhythm is marketing the system for unapproved indications, which would require a new 510(k) submission.
“Your device was cleared under K163512 for long-term monitoring of arrhythmia events for non-critical care patients where real-time monitoring is not needed as reporting timeliness is not consistent with life-threatening arrhythmias,” the FDA said in its letter to iRhythm. “However, your marketing materials and other documentation, such as the document titled ‘Zio AT Notification Criteria,’ and your website, state that the Zio AT Patch System is intended for ‘near real-time monitoring’ as a ‘mobile cardiac telemetry monitor,’ can provide notifications ‘immediately,’ and that it is intended for ‘high-risk patients.’ The claim that the device is intended as a mobile cardiac telemetry monitor implies this device is intended for high-risk patients and near real-time monitoring.”
The FDA said iRhythm’s suggestion that its system is intended for high-risk patients can significantly affect its safety or effectiveness, because those patients are more likely to have a life-threatening arrhythmia and risk serious injury or death without timely treatment.
iRhythm proposed changes to the FDA that the agency deemed inadequate.
The FDA also said iRhythm made hardware and firmware changes to the device that should require a new 510(k) submission for clearance. The agency redacted those specific changes in its warning letter, though it said the changes may affect the basic safety of the system and require new testing. It appears that at least one of the changes an adjustment of an algorithm, which the FDA said could results in “missed or incorrect detection of events or arrhythmias.”
Labeling violations
The FDA said iRhythm also misbranded the Zio AT system by failing to include adequate directions for physicians regarding the system’s transmission limit of 100 patient-triggered and 500 automatically detected arrhythmia events.
“Once the transmission limit is reached, the patient’s data stops being transmitted for review/reporting,” the FDA said. “Thus, when the transmission limit is hit, the device can no longer be used for its intended purpose of transmitting patient ECG for reporting. Further, when the transmission limit is hit, the device can no longer provide near-real time monitoring for high-risk patients.”
iRhythm’s labeling does not warn doctors or patients of the transmission limit or any information about it, which is necessary for them to safely use the system.
“The Zio AT System is misbranded … because its labeling fails to bear adequate directions related to the device’s transmission limit,” the FDA told iRhythm. “Your response did not address this issue.”
Quality System Regulation violations
The FDA further alleged that iRhythm was aware of customer complaints regarding the transmission limit since at least 2019, including two patients who died and significant arrythmias that were not reported to doctors. The agency said iRhythm did not launch corrective and preventive actions (CAPA) until the FDA’s inspection
Since 2017, iRhythm has known that patient data is recorded but inaccessible within the Zeus system if a patient’s registration is incomplete, but the company failed to initiate a CAPA. iRhythm initiated a voluntary recall in September 2022 to notify doctors that patient registration must be completed before monitoring can begin.
In both cases, the agency said the CAPA reports eventually provided by iRhythm were not sufficient to determine whether they were properly conducted.
The FDA also said iRhythm did not conduct a health hazard evaluation (HHE) as required by its CAPA procedure after becoming aware of an error in which patient data was not fully erased from a device before it reuse. When iRhythm followed up with HHEs after the FDA’s intervention, the agency said those HHEs “underestimated the likelihood of someone being injured.”
Medical Device Reporting violations
Finally, the FDA accused iRhythm of Medical Device Reporting (MDR) violations for failing to submit death or injury reports in a timely manner, failing to report dangerous device malfunctions regarding the transmission limit, and failing to develop and implement written MDR procedures.
iRhythm went back and reviewed nearly 1 million complaints from March 2019 to August 2022 and submitted 13 MDRs, but the FDA said it found more events that the company’s review missed.