iPhone 12 MagSafe technology and cardiac implantable devices: Assessment of the actual risk.

BACKGROUND: Pacemaker (PM) and implantable cardioverter defibrillators (ICD) are equipped with a magnetic sensor activated by external application of magnets to easily manage some functions of these devices. If activated inadvertently or outside a controlled environment and without the supervision of clinical personnel, this magnetic mode introduces a potential risk. In reality, the possibility of a static magnetic field affecting a PM or ICD is remote. However, the presence of the magnet in the iPhone 12 made the possibility of inadvertently activating the magnetic switch of PM and ICD less remote. OBJECTIVE: This study investigates the effects of magnetic interference of the iPhone 12 on a large set of cardiac implantable devices representative of the current market and proposes adequate rules of conduct. METHODS: We investigated the risk of the magnetic interference of the iPhone 12 and its MagSafe accessories on a comprehensive set of PMs and ICDs, including the subcutaneous ICD. For the first time, the magnetic interference phenomena were correlated with the magnetic field levels measured all around iPhone 12. RESULTS: We discovered that the magnets inside iPhone 12 trigger the magnetic mode in the 12 tested devices up to a distance of 1 cm. CONCLUSIONS: Considering the implications related to the activation of the magnetic switch, to date, it is advisable to follow Apple's indications relating to the safety distance of 15 cm, which is widely compatible with the results obtained from this paper and in line with the indications provided by the implantable cardiac device manufacturers.

A new insight on postural tachycardia syndrome in 102 adults with hypermobile Ehlers-Danlos Syndrome/hypermobility spectrum disorder.

There is an association between joint hypermobility, hypermobile Ehlers-Danlos syndrome (hEDS) and different forms of orthostatic intolerance. Objective: to explore autonomic profile in a large cohort of adults with hEDS and hypermobility spectrum disorder (hEDS/HSD) with a multimodal approach. In this observational retrospective study, heart rate, blood pressure and baroreflex sensitivity were estimated in 102 hEDS/HSD subjects during deep breathing, Valsalva maneuver, standing up: 30-15 ratio, Head-Up Tilt and sustained handgrip. Abnormal results and head-up tilt test were common and included postural orthostatic tachycardia syndrome (POTS; 48%), orthostatic intolerance (25.5%) and hypotension (3.9%). Baroreflex sensitivity was significantly different in individuals with POTS compared to the others. This study confirms the high rate and heterogeneity of abnormal autonomic regulation in hEDS/HSD, and suggests the baroreflex sensitivity might distinguish comorbid POTS from other profiles in this subgroup of patients. Abnormal autonomic regulation is common in adults with hEDS/HSD and should be regularly assessed for tailoring the management approach.

[Assessment of the risk due to exposure to EMF with particular reference to the protection of sensitive subjects]. / La valutazione del rischio da esposizione a CEM con particolare riguardo alla tutela dei soggetti sensibili.

SUMMARY: Purpose. The work illustrates useful elements for the risk assessment for workers exposed to electromagnetic fields, also in reference to sensitive subjects such as those with active implantable medical devices (AIMD). Methods. The approach introduced by Legislative Decree 81/08 for risk assessment does not explicitly include operational criteria and specific measures for the protection of sensitive subjects. In the case of workers with DMIA, the employer may refer to relevant harmonized technical standards. Results. They are shown the results of in vitro tests performed on pacemakers following the indications of the technical reference standard and employing sources of electromagnetic fields that, due to the type of signal emitted, do not allow to exclude an a priori influence on the operation of the device. Conclusions. Workers at particular risk are generally protected if the requirements established for the population are respected. This measure may, under certain conditions, not be sufficient,making it necessary to carry out more in-depth and individual assessments. However, the cases illustrated here for AIMD showed interference phenomena only in limited experimental configurations despite the levels of the electric and magnetic fields generated by the sources exceeding the limits for the general population.

Brain-Heart Pathways to Blood Pressure-Related Hypoalgesia.

OBJECTIVE: High blood pressure (BP) is associated with reduced pain sensitivity, known as BP-related hypoalgesia. The underlying neural mechanisms remain uncertain, yet arterial baroreceptor signaling, occurring at cardiac systole, is implicated. We examined normotensives using functional neuroimaging and pain stimulation during distinct phases of the cardiac cycle to test the hypothesized neural mediation of baroreceptor-induced attenuation of pain. METHODS: Eighteen participants (10 women; 32.7 (6.5) years) underwent BP monitoring for 1 week at home, and individual pain thresholds were determined in the laboratory. Subsequently, participants were administered unpredictable painful and nonpainful electrocutaneous shocks (stimulus type), timed to occur either at systole or at diastole (cardiac phase) in an event-related design. After each trial, participants evaluated their subjective experience. RESULTS: Subjective pain was lower for painful stimuli administered at systole compared with diastole, F(1, 2283) = 4.82, p = 0.03. Individuals with higher baseline BP demonstrated overall lower pain perception, F(1, 2164) = 10.47, p < .0001. Within the brain, painful stimulation activated somatosensory areas, prefrontal cortex, cingulate cortex, posterior insula, amygdala, and the thalamus. Stimuli delivered during systole (concurrent with baroreceptor discharge) activated areas associated with heightened parasympathetic drive. No stimulus type by cardiac phase interaction emerged except for a small cluster located in the right parietal cortex. CONCLUSIONS: We confirm the negative associations between BP and pain, highlighting the antinociceptive impact of baroreceptor discharge. Neural substrates associated with baroreceptor/BP-related hypoalgesia include superior parietal lobule, precentral, and lingual gyrus, regions typically involved in the cognitive aspects of pain experience.

ANMCO/AIIC/SIT Consensus Information Document: definition, precision, and suitability of electrocardiographic signals of electrocardiographs, ergometry, Holter electrocardiogram, telemetry, and bedside monitoring systems.

The electrocardiogram (ECG) signal can be derived from different sources. These include systems for surface ECG, Holter monitoring, ergometric stress tests, and telemetry systems and bedside monitoring of vital parameters, which are useful for rhythm and ST-segment analysis and ECG screening of electrical sudden cardiac death predictors. A precise ECG diagnosis is based upon correct recording, elaboration, and presentation of the signal. Several sources of artefacts and potential external causes may influence the quality of the original ECG waveforms. Other factors that may affect the quality of the information presented depend upon the technical solutions employed to improve the signal. The choice of the instrumentations and solutions used to offer a high-quality ECG signal are, therefore, of paramount importance. Some requirements are reported in detail in scientific statements and recommendations. The aim of this consensus document is to give scientific reference for the choice of systems able to offer high quality ECG signal acquisition, processing, and presentation suitable for clinical use.

Impact of capped and uncapped abandoned leads on the heating of an MR-conditional pacemaker implant.

PURPOSE: To assess the risk of radiofrequency (RF)-induced heating in patients with MR-conditional pacemaker (PM) systems, in the presence of another lead abandoned from a previous implant. METHODS: Four commercial pacemaker leads were placed beside a MR-conditional PM system, inside a human trunk simulator. The phantom has been exposed to the RF generated by a 64 MHz body bird-cage coil (whole-body specific absorption rate [SAR] = 1 W/kg) and the induced heating was measured at the tip of the abandoned lead and of the MR-conditional implant. Configurations that maximize the coupling between the RF field and the leads have been tested, as well as realistic implant positions. RESULTS: Abandoned leads showed heating behaviors that strongly depend on the termination condition (abandoned-capped or saline exposed) and on the lead path (left or right positioning). Given a whole-body SAR = 1 W/kg, a maximum temperature rise of 17.6°C was observed. The presence of the abandoned lead modifies the RF-heating profile of the MR-conditional implant: either an increase or a decrease in the induced heating at its lead tip can occur, mainly depending on the relative position of the two leads. Variations ranging from -63% to +69% with respect to the MR-conditional system alone were observed. CONCLUSION: These findings provide experimental evidence that the presence of an abandoned lead poses an additional risk for the patient implanted with a MR-conditional PM system. Our results support the current PM manufacturers' policy of conditioning the MR compatibility of their systems to the absence of abandoned leads (including leads from MR-conditional implants). From a clinical point of view, in such cases, the decision whether to perform the exam shall be based upon a risk/benefit evaluation, as in the case of conventional PM systems.

An optically coupled sensor for the measurement of currents induced by MRI gradient fields into endocardial leads.

OBJECT: The gradient fields generated during magnetic resonance imaging (MRI) procedures have the potential to induce electrical current on implanted endocardial leads. Whether this current can result in undesired cardiac stimulation is unknown. MATERIALS AND METHODS: This paper provides a detailed description of how to construct an optically coupled sensor for the measurement of gradient-field-induced currents into endocardial leads. The system is based on a microcontroller that works as analog-to-digital converter and sends the current signal acquired from the lead to an optical high-speed, light-emitting diode transmitter. A plastic fiber guides the light outside the MRI chamber to a photodiode receiver and then to an acquisition board connected to a PC laptop. RESULTS: The performance of the system has been characterized in terms of power consumption (8 mA on average), sampling frequency (20.5 kHz), measurement range (-12.8 to 10.3 mA) and resolution (22.6 µA). Results inside a 3 T MRI scanner are also presented. CONCLUSIONS: The detailed description of the current sensor could permit more standardized study of MRI gradient current induction in pacemaker systems. Results show the potential of gradient currents to affect the pacemaker capability of triggering a heartbeat, by modifying the overall energy delivered by the stimulator.

Risk Assessment for Workers with Wearable Medical Devices Exposed to Electromagnetic Fields.

ABSTRACT: The exponential diffusion of wearable medical devices (WMD) in recent years has involved people of all ages, including workers. Workers who use WMDs should be considered at a particular risk from electromagnetic fields, and in accordance with EU Directive 2013/35/EU, they require an individual risk assessment. Currently, there is no international standard that provides specific guidance on how to perform such a risk assessment. This paper focuses on the effects of electromagnetic fields on WMDs and does not consider the direct effects on human body tissues. It aims to offer practical recommendations to employers and/or health physicists for the risk assessment of workers with WMDs. Focusing on EU countries, we first describe the requirements outlined by the technical standard for the electromagnetic compatibility (EMC) of medical electrical equipment EN 60601-1-2. Then, some general guidelines on how to perform the risk assessment are provided. The assessment can be conducted by comparing the field values measured in the workplace with the immunity test levels specified in the technical standards of medical electrical equipment. If the measured values are lower than the immunity test levels indicated in the standard and the distance from the electromagnetic source is greater than the distance used by the manufacturer during the EMC (electromagnetic compatibility) tests (typically 30 cm), the risk for the worker may be considered acceptable. However, if the measured values exceed the immunity test levels or the distance criteria, a specific evaluation based on a case-by-case analysis is required.

The Italian external quality assessment program for Cystic Fibrosis sweat chloride test: CFTR modulators and the impact of a new sweat test report form.

Background: The advent of CFTR modulators highlighted that the sweat test (ST) for CF can be used also as an outcome measure for the basic defect of CFTR. Despite the technological advances, ST still remains operator-dependent and its execution should be strongly paired with guidelines. In 2022, due to the advent of CFTR modulators, the Italian CF Society introduced a specific ST report. The aim of the present paper is to discuss the impact of this new report in the 2022-23 round of the Italian External Quality Assessment program for ST (I-EQA-SCT). Methods: The scheme of the I-EQA-SCT is prospective, enrolment is voluntary, the payment of a fee is required and results are shared through a web-facility. Assessment covers analysis, interpretation, and reporting of results. In the 2022-23 round, 2 out of the 3 mock clinical information referred to patients who started modulators. Results: Fourteen laboratories completed the 2022-23 I-EQA-SCT round. Three of them failed in the interpretation of results from these two mock cases and/or used a wrong report not consistent with the more recent Italian Sweat Test Recommendations. Conclusions: The overall results obtained from the laboratories involved in the I-EQA-SCT program clearly showed that the laboratories' qualitative and quantitative performance improved significantly. Results emerged from this round highlighted an issue in the report form used for monitoring patients on CFTR modulator therapy thus stressing the importance of these programs in improving both the performance of lab services and ameliorating the sweat test recommendations.

Personalized Antiarrhythmic Therapy Using a Self-Managed Daily-ECG Device.

A 50-year-old Caucasian man arrived at the emergency department presenting paucisymptomatic atrial fibrillation. Once discharged after the appropriate treatments, the patient continued to have paucisymptomatic episodes. For this reason, he was provided with the Cardionica device which made it possible to better investigate the type of arrhythmic episodes, in order to tailor his therapy and to finally restore a normal sinus rhythm in the patient.

Pacemakers, Implantable Defibrillators, and 5G Technology: What We Need to Know.

ABSTRACT: Pacemakers (PM) and implantable cardioverter defibrillators (ICD) are active implantable medical devices (AIMD) needed in case of cardiac arrhythmias. Given their potentially life-sustaining nature, the interaction between any source of electromagnetic field and these AIMDs is an ongoing concern of patients, industry, and regulators. According to the current regulatory framework, the required immunity of PM and ICD provides a reasonable unperturbed behavior in the presence of cell phones and base stations that use pre-5G technologies. PM/ICD international standards do not consider some peculiar characteristics of 5G technology and some of the 5G technology frequency bands (those above 3 GHz), since these frequencies are considered not to add risks to the AIMD functioning. Here we analyze the theoretical issues about the interference between 5G technology and PM/ICD and propose an experimental approach to perform a measurement campaign.

5G Service and Pacemakers/Implantable Defibrillators: What Is the Actual Risk?

Rapidly growing worldwide, 5G service is expected to deeply change the way we communicate, connect and share data. It encompasses the whole spectrum of new technology, infrastructure and mobile connectivity, and will touch not only every sector in the industry, but also many aspects of our everyday life. Although the compliance with international regulations provides reasonable protection to public health and safety, there might be specific issues not fully covered by the current technical standards. Among the aspects that shall be carefully considered, there is the potential interference that can be induced on medical devices, and in particular on implantable medical devices that are critical for the patient's life, such as pacemakers and implantable defibrillators. This study aims to assess the actual risk that 5G communication systems pose to pacemakers and implantable defibrillators. The setup proposed by the ISO 14117 standard was adapted to include 5G characteristic frequencies of 700 MHz and 3.6 GHz. A total number of 384 tests were conducted. Among them, 43 EMI events were observed. Collected results reveal that RF hand-held transmitters operating in these two frequency bands do not pose additional risk compared to pre-5G bands and that the safety distance of 15 cm typically indicted by the PM/ICD manufacturer is still able to guarantee the patient's safety.

Role of the lead structure in MRI-induced heating: In vitro measurements on 30 commercial pacemaker/defibrillator leads.

MRI-induced heating on endocardial leads is a serious concern for the safety of patients with implantable pacemakers or cardioverter-defibrillator. The lead heating depends on many factors and its amount is largely variable. In this study, we investigated the role of those structural properties of the lead that are reported on the accompanying documents of the device: (1) fixation modality (active vs. passive); (2) number of electrodes (unipolar vs. bipolar); (3) length; (4) tip surface; and (5) tip and ring resistance. In vitro temperature and specific absorption rate measurements on 30 leads (27 pacemakers, three implantable cardioverter-defibrillator leads) exposed to the radiofrequency field typical of a 1.5 T MRI scanner are presented. The data show that each lead has its own attitude to radiofrequency-induced heating and that the information that is available in the accompanying documents of the pacemaker is not sufficient to explain such attitude. Even if combined with that of the implant geometry, this information is still not sufficient to estimate the amount of heating due to the exposure to the radiofrequency field during MRI examination.

Daily distribution of atrial arrhythmic episodes in sick sinus syndrome patients: implications for atrial arrhythmia monitoring.

AIMS: Disorders such as paroxysmal atrial fibrillation (AF) and atrial tachyarrhythmias (AT) are difficult to investigate because of their intermittent, and sometimes asymptomatic, nature. The aim of this study was to investigate the daily temporal distribution of AT/AF episodes--onset and occurrence--by analysing data from 250 pacemaker-implanted, brady-tachy syndrome patients who have been enrolled in the Burden II Study. METHODS AND RESULTS: Data were analysed accounting for the mode switch list which includes date, time, and duration of each mode switch episode. Chi-squared tests for goodness of fit were used to determine whether AT/AF episode were uniformly distributed. The population analysed in the present study suggests the occurrence of a circadian rhythm of paroxysmal AF episodes, similar to that described for other cardiovascular diseases, with clustering of events in the morning from 08:00 and (to a lesser degree) in the afternoon (03:00 to 18:00). The relative risk of AT/AF onset is 13% higher during daytime, 40% lower at night (P < 0.000001). CONCLUSION: The use of monitoring devices based on daily electrocardiogram (ECG) recording could be optimized with these data, thus increasing the probability to detect AT/AF episodes.

Workers with Cardiac AIMD Exposed to EMF: Methods and Case Studies for Risk Analysis in the Framework of the European Regulations.

Workers with cardiac active implantable medical devices (AIMD), such as a pacemaker (PM) or an implantable defibrillator (ICD), are considered by the occupational health and safety regulation framework as a particularly sensitive risk group that must be protected against the dangers caused by the interference of electromagnetic field (EMF). In this paper, we first describe the general methodology that shall be followed for the risk assessment of employees with a cardiac AIMD exposed to EMF, according to the EU regulation, and in particular to the EN 50527-2-1:2016 and 50527-2-2:2018 standards. Then, three case studies related to specific EMF sources are presented, to better describe how the initial analysis of the risk assessment can be performed in practice, and to understand if a further specific risk assessment analysis is required or not.

Electrical Stun Gun and Modern Implantable Cardiac Stimulators: Update for a New Stun Gun Model.

ABSTRACT: In 2017, the Italian National Institute of Health conducted a study to evaluate the potential risks of Conducted Electrical Weapons (CEW, AKA "stun guns") for users bearing a pacemaker (PM) or an implantable cardioverter defibrillator (ICD). The study addressed two specific models of stun guns: the TASER model X2 and AXON model X26P. In 2019, the same experimental protocol and testing procedure was adopted to evaluate the risk for another model of stun gun, the MAGEN model 5 (MAGEN, Israel). The MAGEN 5 differs from the previous stun guns tested in terms of peak voltage generated, duration of the shock, and trigger modality for repeated shocks. This note is an update of the previous study results, including the measurements on the MAGEN 5 stun gun. Despite the differences between the stun gun models, the effects on the PM/ICD behavior were the same as previously observed for the TASER stun guns.

Estimate and reporting of longevity for cardiac implantable electronic devices: a proposal for standardized criteria.

BACKGROUND: Cardiac implantable electronic devices (CIEDs) are widely used according to consensus guidelines in various patient categories. The longevity of CIED is a major determinant of the frequency with which patients require device replacement. Given the mismatch between the useful life of the devices and patient survival, device replacement is often needed. There is a great variability in the criteria used by manufacturers to determine the longevity of pacemakers (PM), implantable defibrillators (ICDs), and devices for cardiac resynchronization therapy (CRT). Thus, a fair comparison and an effective device evaluation is often difficult. METHODS: The objective of this paper is to provide standardized criteria based on typical clinical settings for estimating the longevity of single and dual chamber ICDs, cardiac resynchronization defibrillators (CRT-D), single and dual chamber PMs, and cardiac resynchronization PMs (CRT- P) to be used in health technology assessment for an appropriate comparison among different devices. RESULTS: The proposed parameters, if applied to the current marketed devices, provide longevity values in the range 5-17.2 years. CONCLUSION: The values of longevity with the non-standardized criteria used by the manufacturers result in higher maximum values respect to the proposed standardized criteria for CRT-D, CRTD-MPP, CRT-P, and Dual-chamber PM.

Autonomic function during closed loop stimulation and fixed rate pacing: heart rate variability analysis from 24-hour Holter recordings.

AIM: Aim of this retrospective study was to analyze the effect of closed-loop stimulation (CLS) and DDD pacing mode on autonomic balance, and to evaluate heart rate variability (HRV) during CLS stimulation. METHODS AND MATERIALS: Autonomic balance was estimated by a 24-hour HRV analysis of paced and spontaneous beats in patients implanted with a dual-chamber pacemaker (Inos(2+) CLS-Biotronik GmbH, Berlin, Germany) and randomly assigned to CLS or DDD pacing mode. Patients underwent two 24-hour electrocardiogram Holter recordings at the end of each 3-month pacing mode period. Each Holter recording was automatically scanned to extract sequences of consecutive beats of the same type [atrial paced (Ap)-sequence and atrial spontaneous (As)-sequence], lasting at least 130 beats. RESULTS: Eight hundred and ten sequences were extracted from 15 patients, and the following spectral parameters were evaluated during both CLS and DDD mode: the total power (variance), the absolute and percentage (relative to the total power) powers of the low frequency (LF, 0.04-0.15 Hz) and high frequency (HF, 0.15-0.4 Hz) components, as well as the LF/HF power ratio. DISCUSSION: The two main findings of this study were: in all the patients, CLS seems to mimic short-term physiological HRV, although the variability (total power) was lower than that relative to the spontaneous beats; the HRV of the spontaneous beats had an higher LF/HF when the pacemaker was programmed as DDD respect to CLS, consistent with a shift toward sympathetic predominance.

The Italian External Quality Assessment Program for Cystic Fibrosis Sweat Chloride Test: Does Active Participation Improve the Quality?

(1) Background: Diagnostic testing for cystic fibrosis (CF) is based on a sweat chloride test (SCT) considering the appropriate signs and symptoms of the disease and results of a gene mutation analysis. In 2014, the Istituto Superiore di Sanità (ISS) established a pilot Italian external quality assessment program for CF SCT (Italian EQA-SCT), which is now a third party service carried out by the ISS. (2) Methods: The ongoing scheme is prospective, enrollment is voluntary, and the payment of a fee is required. Results are shared through a dedicated web-facility. Assessment covers the analysis, interpretation, and reporting of results. (3) Results: Thirteen, fifteen, sixteen, and fifteen different laboratories, respectively, participated from 2015 to 2016 and from 2018 to 2019 in the Italian EQA-SCT scheme. Eleven different laboratories participated each year in all four rounds of the Italian EQA-SCT. (4) Conclusions: The overall results obtained from the laboratories participating constantly clearly show that their qualitative and quantitative performance improved significantly. This is due to the opportunity-after receiving the EQA results-to constantly review their performance and address any inconsistencies. We firmly believe that participation in the EQA program will improve the quality of participating laboratories and that EQA participation should become mandatory as a fundamental requirement for laboratory accreditation.

Electrical Stun Gun and Modern Implantable Cardiac Stimulators.

The aim of the study is to investigate systematically the possible interactions between two types of stun guns and last-generation pacemakers and implantable defibrillators. Experimental measurements were performed on pacemakers and implantable defibrillators from five leading manufacturers, considering the effect of stun gun dart positioning, sensing modality, stun gun shock duration, and defibrillation energy level. More than 300 measurements were collected. No damage or permanent malfunction was observed in either pacemakers or implantable defibrillators. During the stun gun shock, most of the pacemakers entered into the noise reversion mode. However, complete inhibition of the pacing activity was also observed in some of the pacemakers and in all the implantable defibrillators. In implantable defibrillators, standard stun gun shock (duration 5 s) caused the detection of a shockable rhythm and the start of a charging cycle. Prolonged stun gun shocks (10-15 s) triggered the inappropriate delivery of defibrillation therapy in all the implantable defibrillators tested. Also in this case, no damage or permanent malfunction was observed. For pacemakers, in most cases, the stun guns caused them either to switch to the noise reversion mode or to exhibit partial or total pacing inhibition. For implantable defibrillators, in all cases, the stun guns triggered a ventricular fibrillation event detection. No risks resulted when the stun gun was used by a person wearing a pacemaker or an implantable defibrillator. This work provides novel and up-to-date evidence useful for the evaluation of risks to pacemaker/implantable defibrillator wearers due to stun guns.