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Federal regulators posted three Class 2 recall records on Wednesday covering the server software behind Boston Scientific's LUX-Dx family of implanted heart monitors, after the company identified a flaw that can delay alerts about atrial fibrillation. The implanted devices themselves are working as designed, and Boston Scientific is not recommending that anyone have a monitor removed.

The distinction between the implant and the software that receives its data is the whole story here, and it is the part most likely to alarm patients unnecessarily. LUX-Dx monitors are small devices placed under the skin to watch continuously for abnormal heart rhythms. They continue to detect atrial fibrillation, store the data, and transmit it. What can be delayed is one specific notification that reaches the clinical team through the LATITUDE Clarity server.

Atrial fibrillation is the most common sustained heart rhythm disorder, and untreated episodes raise stroke risk substantially. That is why the timing of an alert matters even when the hardware is functioning.

The Configuration That Triggers the Problem

According to the FDA recall record covering the United States software, listed as recall number Z-3081-2026, the delay occurs only when the AF Burden Alert threshold is configured to greater than zero hours per day. That is a non-default setting, which means most patients are not affected by it.

When the threshold is set that way, notification of an AF Burden Alert may be delayed, which in turn may delay clinical evaluation or therapeutic intervention for an atrial arrhythmia. The FDA attributed the cause to software design.

Boston Scientific has received one complaint related to the behavior. No patient injuries or deaths have been reported. The company sent an Urgent Medical Device Correction to customers in August and says a server software update is planned to fix it. The recall records remain open, meaning the correction is not yet complete across all affected products.

The company initiated the action on August 6, and the FDA posted the classification records on September 2. The gap between company action and public posting is routine for device recalls, since the agency classifies severity after the firm reports the correction.

Insertable cardiac monitors are typically implanted in patients being evaluated for unexplained fainting, palpitations, or suspected atrial fibrillation, and in stroke survivors whose stroke had no identified cause. In that last group especially, catching an arrhythmia can determine whether a patient is started on an anticoagulant.

Three Records for One Problem

A detail worth flagging for anyone tracking this: the FDA created three separate recall records under a single recall event identified as 99524, one for each regional version of the server software.

Z-3081-2026 covers the United States version, model number 7260, at a current version of 7.8. Z-3082-2026 covers the European version, model 7246, and Z-3083-2026 covers the Australia and New Zealand version, model 7248, both at a current version of 7.7. All three carry the same reason for recall, the same FDA determined cause and the same September 2 posting date. All three are Class 2, the middle severity tier the FDA uses when a product may cause temporary or medically reversible harm.

Distribution is listed as worldwide, with nationwide distribution in the United States. The records do not specify how many patients or facilities are affected.

Interim Steps That Belong to Clinicians, Not Patients

Boston Scientific outlined two options for managing the issue until the software update arrives, and both are settings changes made by the clinical team rather than anything a patient can do.

Clinics can change the threshold for the AF Burden Alert setting, or they can enable the AF Events Alert with a minimum duration. The LATITUDE Clarity system detects atrial fibrillation through two independent mechanisms, AF Burden and AF Event alerts, so configuring the second one provides a workaround while the first is affected.

The company asked customers to share the notification with all clinicians in their organization who manage patients using LUX-Dx monitors and the LATITUDE Clarity system. Boston Scientific also noted that regulatory authorities in affected countries were informed, and that adverse events should be reported through standard channels.

For patients, the practical action is limited and specific. Anyone with a LUX-Dx, LUX-Dx II or LUX-Dx II+ monitor can contact their cardiology or electrophysiology clinic to ask whether their alert settings use the affected configuration and whether the clinic has applied one of the interim options. Nobody should stop transmitting data, skip a scheduled follow-up, or consider removal. The FDA explains what a device recall means and notes that many recalls involve corrections rather than product removal, which is the case here.

Symptoms That Warrant Attention Regardless of Alerts

Remote monitoring is a supplement to symptom awareness, not a replacement for it, and this recall is a reminder of why that distinction matters.

Atrial fibrillation can produce a fluttering or racing heartbeat, an irregular pulse, shortness of breath, fatigue, reduced exercise tolerance, dizziness, or chest discomfort. Some people feel nothing at all, which is precisely the reason these monitors exist and why a delayed alert is worth taking seriously even in the absence of reported harm. Anyone experiencing chest pain, severe shortness of breath, fainting or signs of stroke including sudden face drooping, arm weakness or speech difficulty should call 911 rather than wait for a device notification.

People taking anticoagulants for atrial fibrillation should continue them as prescribed. No one should change a medication based on a device recall.

Boston Scientific has not published a date for the server software update. The FDA recall records will be updated as the status changes and will show as terminated once the correction is complete.

Key Questions Answered

Does this recall mean the implanted device must be removed? No. Boston Scientific explicitly does not recommend replacement of the implanted monitor. The recall covers server software, and the implant continues to detect, store, and transmit data as intended.

What exactly can go wrong? Notification of an AF Burden Alert may be delayed, which could delay clinical evaluation or treatment of an atrial arrhythmia. It occurs only when the alert threshold is set to a non-default configuration.

Has anyone been harmed? Boston Scientific reported one complaint about the delayed notification behavior. No patient injuries or deaths have been reported in the FDA records.

What does Class 2 mean? Class 2 is the FDA's middle severity classification, used when a product may cause temporary or medically reversible adverse health consequences, with a remote probability of serious harm.

Which products are covered? Server software supporting the LUX-Dx, LUX-Dx II and LUX-Dx II+ Insertable Cardiac Monitor System. Three records cover the United States, European, and Australia and New Zealand versions under one recall event.

What should a patient with one of these monitors do? Contact the cardiology or electrophysiology clinic to ask about alert settings and whether an interim configuration has been applied. Continue transmissions, follow-ups, and prescribed medications.

When will the software be fixed? Boston Scientific says a server software update is planned but has not published a date. The FDA records remain open until the correction is complete.

Originally published on Medical Daily