Pacemakers

Magnets in some Apple, Microsoft products may interfere with ICDs, pacemakers

Posted by

0


Strong magnets in newer portable electronic devices like the Apple AirPods Pro charging case or Microsoft Surface Pen can interfere with pacemakers and implantable cardioverter defibrillators, researchers reported.

Corentin Féry

“We show that there is a risk of deactivating the therapy of these medical devices if some electronic objects with magnets are placed near the chest of the patients,” Corentin Féry, MSc, a research engineer at the University of Applied Sciences and Arts Northwestern Switzerland, Institute for Medical Engineering and Medical Informatics in Muttenz, Switzerland, told Healio. “The key word is caution for wearers of ICDs and pacemakers. The risk for death is real for them since a tachycardia will not be detected if a device with a strong magnet is deactivating their implant. Our tests on some everyday objects, such as the iPhone 12 Pro Max or the Microsoft Surface Pen, lead us to say that it is necessary to keep a distance of at least 1 inch between the implants and these devices. We also recommend not to carry electronic objects in a pocket close to the chest, or to fall asleep with such devices.”

Phone

Investigating magnetic strength

The researchers investigated several portable electronic devices (PEDs), including the Apple AirPods Pro and its wireless charging case, the Microsoft Surface Pen and the Apple Pencil (second generation), comparing their magnetic field strength with the iPhone 12 Pro Max. Using a magnetic mapper with 64 magnetic sensors, researchers measured the magnetic field strength of the products at various distances. The PEDs were also placed incrementally closer to five defibrillators from two representative manufacturers (Boston Scientific: Inogen, Teligen and Cognis; Medtronic: Protecta and Viva Quad) until a therapy deactivation occurred. According to the FDA, a minimal field strength of 10 G is required for CV implantable devices to trigger to magnet mode.

The findings were published in Circulation: Arrhythmia and Electrophysiology.

The researchers found the farthest point where a 10 G intensity was measured is located about 2 cm (0.78 in) from the surface for the Apple products and at 2.9 cm (1.14 in) for the Microsoft Surface Pen. Magnet reversion mode was triggered at a distance between 8 mm and 18 mm for the tested PEDs.

“Our study found that PEDs other than the iPhone 12 have magnetic susceptibility and, thus, have the potential to inhibit lifesaving therapies,” the researchers wrote.

Although the test results showed the maximum distance for a possible ICD interaction, researchers said for safety, the minimal distance is between 0.8 cm (0.31 in) for the iPhone 12 Pro Max and the Apple Pencil (second generation) and 1.8 cm (0.71 in) for the Microsoft Surface Pen and the opened charging case of the Apple AirPods Pro.

“Clinicians should warn their patients to be cautious when using electronic devices,” Féry told Healio. “Since we have not tested all electronic devices on the market, we suggest caution with any device that has magnets.”

Sven Knecht

Sven Knecht, DSc, a research engineer at the Cardiovascular Research Institute Basel at University Hospital Basel, University of Basel in Switzerland, noted that the magnet mode does deactivate the therapy but not the detection of the tachycardia.

“Furthermore, the risk of death is theoretically possible if the deactivation of the ICD by the portable electronic device occurs during a lethal, hemodynamically relevant tachycardia,” Knecht told Healio. “This likelihood might, however, be relatively low.”

More research needed

A major limitation of the study was that it was not conducted on ICDs implanted in patients, Féry said, adding the researchers need to perform in vivo tests with the electronic devices, as well as highlight the potential risk with other classes of objects, such as watches or e-cigarettes.

As Healio previously reported, the FDA issued a warning in May that certain cellphones and smartwatches containing high field strength magnets may cause some implanted medical devices, particularly cardiac devices, to suspend normal operations when in proximity to the magnet. The FDA noted at the time that many implanted medical devices such as pacemakers and ICDs are designed with a “magnet mode” to allow safe operation during certain medical procedures such as MRI. Placing certain cellphones and smartwatches too close to the implanted device can cause the device to switch into magnet mode when it is not supposed to, suspending normal operations, the agency stated.

The American Heart Association recommends keeping cellphones at least 6 inches away from ICDs or pacemakers by using it on the ear opposite from the implantation and to avoid keeping the cellphone in a front chest pocket.

N.A. Mark A. Estes

“The current study extends observations on magnetic field interactions with even more devices containing magnets,” N.A. Mark A. Estes, MD, professor of medicine and director of the Clinical Cardiac Electrophysiology Fellowship Program at the Heart and Vascular Institute of the University of Pittsburgh School of Medicine, and an AHA volunteer, said in a press release. “Patients with cardiac electronic implantable devices should be instructed to keep all electronic devices that can generate a magnetic field several inches from their pacemakers or ICDs.”

MRI May Still be OK for Legacy Cardiac Devices

Posted by

0


MRI scanning may be safe even for patients with legacy pacemakers or implantable cardioverter-defibrillators (ICDs) not known to be MRI-ready, as long as a safety protocol is followed, a prospective study suggested.

The most important event to watch out for was device reset to a backup mode immediately after scanning, according to Saman Nazarian, MD, PhD, of University of Pennsylvania Perelman School of Medicine, and colleagues. This happened in nine out of 2,103 scans (0.4%), where eight of those resets were transient.

The one case where a reset couldn’t be fixed by device reprogramming was when a patient had a legacy pacemaker with less than 1 month of battery life left; the device had to be replaced, the authors reported online in the New England Journal of Medicine.

“If power-on reset occurs, the device reverts to an inhibited pacing mode. Therefore, in pacing-dependent patients, the device may transiently cease pacing because of electromagnetic interference, and electrocardiographic monitoring and pulse oximetry are warranted so that the scanning can be stopped if inhibition of pacing occurs,” they said.

A prespecified safety protocol dictated that pacing be switched to asynchronous mode for pacing-dependent patients; pacing placed in demand mode for others; and tachyarrhythmia functions disabled.

When it came to changes in device parameters, 1% of patients had P-wave amplitude fall by at least 50% after going into the MRI.

No adverse events observed in the 63% of patients that had a follow-up at 1 year. By then, device interrogations showed that the most common changes (by ≥50%) were:

  • Decreases in P-wave amplitude (4%)
  • Increases in P-wave amplitude (4%)
  • Increases in atrial capture threshold (4%)
  • Increases in right ventricular capture threshold (4%)
  • Increases in left ventricular capture threshold (3%)

“No change in device parameters that occurred either immediately after the MRI or at long-term follow-up in any patient was large enough to result in lead or system revision or device reprogramming,” Nazarian’s group emphasized.

Their study population was a group of 1,509 patients who underwent 1.5-Tesla MRI scans deemed clinically necessary despite having a pacemaker (58%) or ICD (42%) not meeting FDA criteria for being MRI-conditional. Clinicians performed device interrogation at baseline and immediately after the MRI.

“In our smaller study that was reported previously, we noted an association between thoracic imaging and changes in long-term right ventricular sensing and capture threshold. However, the current larger study, in which the follow-up period was longer, does not suggest any association between the region of imaging and detrimental changes in device parameters,” according to Nazarian’s group.

“The primary detrimental associations were a larger reduction in right atrial and right ventricular lead sensing immediately after the MRI with ICD systems than with pacemakers, as well as a larger reduction in long-term right ventricular lead sensing with longer lead length than with shorter lead length.”

Besides being a single-center study, the analysis included patients with a wide variety of cardiac devices, so the number of each pacemaker or ICD included was small. Furthermore, a 20% rate of patients lost to follow-up was a major study limitation.

Even so, they maintained, the present findings complement those of the older, similar MagnaSafe Registry.

Yes, You Can Hack a Pacemaker (and Other Medical Devices Too).

Posted by

0


On Sunday’s episode of the Emmy award-winning show Homeland, the Vice President of the United States is assassinated by a group of terrorists that have hacked into the pacemaker controlling his heart. In an elaborate plot, they obtain the device’s unique identification number. They then are able to remotely take control and administer large electrical shocks, bringing on a fatal heart attack.

Viewers were shocked — many questioned if something like this was possible in real life. In short: Yes (except, the part about the attacker being halfway across the world is questionable). For years, researchers have been exposing enormous vulnerabilities in Internet-connected implanted medical devices.

There are millions of people who rely on these brilliant technologies to stay alive. But as we put more electronic devices into our bodies, there are serious security challenges that must be addressed. We are familiar with the threat that cyber-crime poses to the computers around us — however, we have not yet prepared for the threat it may pose to the computers inside of us.

Implanted devices have been around for decades, but only in the last decade have these devices become virtually accessible. While they allow for doctors to collect valuable data, many of these devices were distributed without any type of encryption or defensive mechanisms in place. Unlike a regular electronic device that can be loaded with new firmware, medical devices are embedded inside the body and require surgery for “full” updates. One of the greatest constraints to adding additional security features is the very limited amount of battery power available.

Thankfully, there have been no recorded cases of a death or injury resulting from a cyber attack on the body. All demonstrations so far have been conducted for research purposes only. But if somebody decides to use these methods for nefarious purposes, it may go undetected.

Marc Goodman, a global security expert and the track chair for Policy, Law and Ethics at Singularity University, explains just how difficult it is to detect these types of attacks. “Even if a case were to go to the coroner’s office for review,” he asks, “how many public medical examiners would be capable of conducting a complex computer forensics investigation?” Even more troubling was, “The evidence of medical device tampering might not even be located on the body, where the coroner is accustomed to finding it, but rather might be thousands of kilometers away, across an ocean on a foreign computer server.”

Since knowledge of these vulnerabilities became public in 2008, there have been rapid advancements in the types of hacking successfully attempted.

The equipment needed to hack a transmitter used to cost tens of thousands of dollars; last year a researcher hacked his insulin pump using an Arduino module that cost less than $20. Barnaby Jack, a security researcher at McAfee, in April demonstrated a system that could scan for and compromise insulin pumps that communicate wirelessly. With a push of a button on his laptop, he could have any pump within 300 feet dump its entire contents, without even needing to know the devices’ identification numbers. At a different conference, Jack showed how he reverse engineered a pacemaker and could deliver an 830-volt shock to a person’s device from 50 feet away — which he likened to an “anonymous assassination.”

There have also been some fascinating advancements in the emerging field of security for medical devices. Researchers have created a “noise” shield that can block out certain attacks — but have strangely run into problems with telecommunication companies looking to protect their frequencies. There have been the discussions of using ultrasound waves to determine the distance between a transmitted and medical device to prevent far-away attacks. Another team has developed biometric heartbeat sensors to allow devices within a body to communicate with each other, keeping out intruding devices and signals.

But these developments pale in comparison to the enormous difficulty of protecting against “medical cybercrime,” and the rest of the industry is falling badly behind.

In hospitals around the country there has been a dangerous rise of malware infections in computerized equipment. Many of these systems are running very old versions of Windows that are susceptible to viruses from years ago, and some manufacturers will not allow their equipment to be modified, even with security updates, partially due to regulatory restrictions. A solution to this problem requires a rethinking of the legal protections, the loosening of equipment guidelines, as well as increased disclosure to patients.

Government regulators have studied this issue and recommended that the FDA take these concerns into account when approving devices. This may be a helpful first step, but the government will not be able to keep up with the fast developments of cyber-crime. As the digital and physical world continue to come together, we are going to need an aggressive system of testing and updating these systems. The devices of yesterday were not created to protect against the threats of tomorrow.

Source:Forbes