Cardiac Rhythm Management Devices Research Articles

Keeping People in Rhythm Electronically – An Overview of Cardiac Rhythm Management Devices

Keeping People in Rhythm Electronically – An Overview of Cardiac Rhythm Management Devices

Sustainability inspired fabrication of next generation neurostimulation and cardiac rhythm management electrodes via reactive hierarchical surface restructuring

Over the last two decades, platinum group metals (PGMs) and their alloys have dominated as the materials of choice for electrodes in long-term implantable neurostimulation and cardiac rhythm management devices due to their superior conductivity, mechanical and chemical stability, biocompatibility, corrosion resistance, radiopacity, and electrochemical performance. Despite these benefits, PGM manufacturing processes are extremely costly, complex, and challenging with potential health hazards. Additionally, the volatility in PGM prices and their high supply risk, combined with their scarce concentration of approximately 0.01 ppm in the earth’s upper crust and limited mining geographical areas, underscores their classification as critical raw materials, thus, their effective recovery or substitution worldwide is of paramount importance. Since postmortem recovery from deceased patients and/or refining of PGMs that are used in the manufacturing of the electrodes and microelectrode arrays is extremely rare, challenging, and highly costly, therefore, substitution of PGM-based electrodes with other biocompatible materials that can yield electrochemical performance values equal or greater than PGMs is the only viable and sustainable solution to reduce and ultimately substitute the use of PGMs in long-term implantable neurostimulation and cardiac rhythm management devices. In this article, we demonstrate for the first time how the novel technique of “reactive hierarchical surface restructuring” can be utilized on titanium—that is widely used in many non-stimulation medical device and implant applications—to manufacture biocompatible, low-cost, sustainable, and high-performing neurostimulation and cardiac rhythm management electrodes. We have shown how the surface of titanium electrodes with extremely poor electrochemical performance undergoes compositional and topographical transformations that result in electrodes with outstanding electrochemical performance.

Perspectives on the Longevity of Cardiac Rhythm Management Devices

Perspectives on the Longevity of Cardiac Rhythm Management Devices

British Heart Rhythm Society Standards for Implantation and Follow-up of Cardiac Rhythm Management Devices in Adults: January 2024 Update.

This updated guidance is designed to help with implantation and follow-up with agreed standards of practice. The update includes new guidance on subcutaneous defibrillators, leadless pacemakers and conduction system pacing. It includes new guidance on considerations at the time of a potential box change and techniques to be considered to minimise the risk of infection.

2-Year Outcomes of an Atrial Shunt Device in HFpEF/HFmrEF: Results From REDUCE LAP-HF II

BackgroundThe REDUCE LAP-HF II (Reduce Elevated Left Atrial Pressure in Patients With Heart Failure II) trial found that, compared with a sham procedure, the Corvia Atrial Shunt did not improve outcomes in heart failure with preserved or mildly reduced ejection fraction. However, after 12-month follow-up, “responders” (peak-exercise pulmonary vascular resistance <1.74 WU and absence of a cardiac rhythm management device) were identified. ObjectivesThis study sought to determine: 1) the overall efficacy and safety of the atrial shunt vs sham control after 2 years of follow-up; and 2) whether the benefits of atrial shunting are sustained in responders during longer-term follow-up or are offset by adverse effects of the shunt. MethodsThe study analyzed 2-year outcomes in the overall REDUCE LAP-HF II trial, as well as in responder and nonresponder subgroups. The primary endpoint was a hierarchical composite of cardiovascular death or nonfatal ischemic/embolic stroke, total heart failure events, and change in health status. ResultsIn 621 randomized patients, there was no difference between the shunt (n = 309) and sham (n = 312) groups in the primary endpoint (win ratio: 1.01 [95% CI: 0.82-1.24]) or its individual components at 2 years. Shunt patency at 24 months was 98% in shunt-treated patients. Cardiovascular mortality and nonfatal ischemic stroke were not different between the groups; however, major adverse cardiac events were more common in those patients assigned to the shunt compared with sham (6.9% vs 2.7%; P = 0.018). More patients randomized to the shunt had an increase in right ventricular volume of ≥30% compared with the sham control (39% vs 28%, respectively; P < 0.001), but right ventricular dysfunction was uncommon and not different between the treatment groups. In responders (n = 313), the shunt was superior to sham (win ratio: 1.36 [95% CI: 1.02-1.83]; P = 0.037, with 51% fewer HF events [incidence rate ratio: 0.49 [95% CI: 0.25-0.95]; P = 0.034]). In nonresponders (n = 265), atrial shunting was inferior to sham (win ratio: 0.73 [95% CI: 0.54-0.98]). ConclusionsAt 2 years of follow-up in REDUCE LAP-HF II, there was no difference in efficacy between the atrial shunt and sham groups in the overall trial group. The potential clinical benefit identified in the responder group after 1 and 2 years of follow-up is currently being evaluated in the RESPONDER-HF (Re-Evaluation of the Corvia Atrial Shunt Device in a Precision Medicine Trial to Determine Efficacy in Mildly Reduced or Preserved Ejection Fraction Heart Failure) trial. (Reduce Elevated Left Atrial Pressure in Patients With Heart Failure II [REDUCE LAP-HF II]; NCT03088033)

Atrial Shunt Device Effects on Cardiac Structure and Function in Heart Failure With Preserved Ejection Fraction

Although the results of A Study to Evaluate the Corvia Medical Inc IASD System II to Reduce Elevated Left Atrial Pressure in Patients with Heart Failure (REDUCE LAP-HF II) trial were neutral overall, atrial shunt therapy demonstrated potential efficacy in responders (no latent pulmonary vascular disease and no cardiac rhythm management device). Post hoc analyses were conducted to evaluate the effect of shunt vs sham stratified by responder status. To evaluate the effect of atrial shunt vs sham control on cardiac structure/function in the overall study and stratified by responder status. This was a sham-controlled randomized clinical trial of an atrial shunt device in heart failure with preserved ejection fraction (HFpEF)/HF with mildly reduced EF (HFmrEF). Trial participants with evaluable echocardiography scans were recruited from 89 international medical centers. Data were analyzed from April 2023 to January 2024. Atrial shunt device or sham control. Changes in echocardiographic measures from baseline to 1, 6, 12, and 24 months after index procedure. The modified intention-to-treat analysis of the REDUCE LAP-HF II trial included 621 randomized patients (median [IQR] age, 72.0 [66.0-77.0] years; 382 female [61.5%]; shunt arm, 309 [49.8%]; sham control arm, 312 [50.2%]). Through 24 months, 212 of 217 patients (98%) in the shunt arm with evaluable echocardiograms had patent shunts. In the overall trial population, the shunt reduced left ventricular (LV) end-diastolic volume (mean difference, -5.65 mL; P <.001), left atrial (LA) minimal volume (mean difference, -2.8 mL; P =.01), and improved LV systolic tissue Doppler velocity (mean difference, 0.69 cm/s; P <.001) and LA emptying fraction (mean difference, 1.88 percentage units; P =.02) compared with sham. Shunt treatment also increased right ventricular (RV; mean difference, 9.58 mL; P <.001) and right atrial (RA; mean difference, 9.71 mL; P <.001) volumes but had no effect on RV systolic function, pulmonary artery pressure, or RA pressure compared with sham. In the shunt arm, responders had smaller increases in RV end-diastolic volume (mean difference, 5.71 mL vs 15.18 mL; interaction P =.01), RV end-systolic volume (mean difference, 1.58 mL vs 7.89 mL; interaction P =.002), and RV/LV ratio (mean difference, 0.07 vs 0.20; interaction P <.001) and larger increases in transmitral A wave velocity (mean difference, 5.08 cm/s vs -1.97 cm/s; interaction P =.02) compared with nonresponders randomized to the shunt, suggesting greater ability to accommodate shunted blood through the pulmonary circulation enabling LA unloading. In this post hoc analysis of the REDUCE LAP-HF II trial, over 2 years of follow-up, atrial shunting led to reverse remodeling of left-sided chambers and increases in volume of right-sided chambers consistent with the shunt flow but no change in RV systolic function compared with sham. Changes in cardiac structure/function were more favorable in responders compared with nonresponders treated with the shunt, supporting the previously identified responder group hypothesis and mechanism, although further evaluation with longer follow-up is needed. ClinicalTrials.gov Identifier: NCT03088033.

PO-04-147 LEADLESS PACING IN ADULT CONGENITAL HEART DISEASE PATIENTS: MULTI-CENTRE UK EXPERIENCE

A significant number of Adults with Congenital Heart Disease (ACHD) require cardiac rhythm management devices. Implantation of endocardial or epicardial pacemakers presents specific challenges in this population. The Micra leadless pacemakers have potential to overcome some of these challenges. To assess the utility of Micra implant in ACHD population. A retrospective analyses of Micra implants undertaken at Barts Heart Centre, London and Liverpool Heart and Chest Hospital in the ACHD population between 2020-2022. Data was collected from a prospective registry and electronic health records. Patients were contacted for follow-up data where necessary. 26 AV Micras were implanted across the two centres over two years. 52% females with mean age of 37 yrs. 42% were anticoagulated with warfarin or a DOAC. Underlying etiology – Figure 1. Micra indication – Table 1. Mean procedure and fluoroscopy times were 57±21min and 7±1 min. Access site was femoral in 77% and transjugular in 23%. Mean sensing and thresholds were 11±0.4mV and 0.6±0.09V at 0.24ms respectively. There were no acute procedural complications. Over a mean follow-up of 13 months there were no significant programming issues or change in pacing parameters. One patient had high thresholds and one died of non-cardiac causes. Micra implants should be considered in cases where endocardial or epicardial implants are contraindicated or represent an otherwise suboptimal approach. They have advantages in ACHD patients with complex cardiac anatomy, difficult venous access and need for repeat procedures. Larger multicentre studies and longer follow-ups are required.Tabled 1Table 1Micra Indicationn, %Failed endocardial system6,23Failed epicardial system6,23Bridge to CRTP3,12SVC occlusion3,12Other8,30 Open table in a new tab

MRI conditional safety of mixed systems: Study of the impact of active implant medical device impedance on the radiofrequency-induced lead heating.

The aim of this paper is to study the impact of pulse generator small impedance variations on the overall radiofrequency (RF)-induced heating of a cardiac rhythm management (CRM) lead in a 1.5 T MR system. An analysis was conducted on two CRM pacing leads with different structural designs. The leads were connected to three CRM devices belonging to different technological platforms: two pacemakers and a cardiac resynchronization therapy defibrillator (CRT-D). All pulse generators had a small (< ) RF input impedance compared to the overall system (pulse generator and lead) impedance. In addition, two Dummy load devices with an input impedance that is not negligible compared to the lead impedance were also studied. The implantable systems were studied in terms of RF deposited power at the lead electrodes, which is proportional to the RF-induced heating. Results show that both leads behave very similarly in terms of RF deposited power for the same in-vivo tangential E-field excitation when mounting any of the pulse generators; reported differences are well below the combined uncertainty . On the other hand, both Dummy load devices resulted in a RF deposited power which differs from the other pulse generators by values larger than the combined uncertainty. The results of our experimental analysis show that different pulse generators would not change the RF-induced heating behavior of a given lead, provided that the pulse generator impedances are small (in our study less than 5%) compared to the overall system impedance.

Two Implantable Devices for Cardiac Rhythm Management

A 53-year-old, 104- kg, 165- cm woman with nonischemic cardiomyopathy with a reduced ejection fraction of 30%-to-35% secondary to cardiac sarcoidosis was admitted for decompensated heart failure. She previously had a single-chamber implantable cardioverter-defibrillator (ICD) placed via a left pectoral approach for the primary prevention of sudden cardiac death. Considering that the patient was on maximally tolerable guideline-directed medical therapy for heart failure with reduced ejection fraction, and was not a candidate for cardiac resynchronization therapy, the decision was made to augment her systolic function with a cardiac rhythm management device. After an uneventful implantation of her new device, a chest radiograph (Fig 1) and electrocardiogram showing changes (Fig 2, Fig 3) were obtained. What is the diagnosis? Fig 2Electrocardiogram with cardiac contractility modulation therapy OFF. View Large Image Figure Viewer Download Hi-res image Fig 3Electrocardiogram with cardiac contractility modulation therapy ON. View Large Image Figure Viewer Download Hi-res image

Bimodal distribution of QRS complex duration in patients with dilated cardiomyopathy undergoing an ICD implant procedure

Abstract Background/Introduction In patients with heart failure with reduced ejection fraction (HFrEF), QRS duration is of the uttermost importance. Substantial proportion of patients with HFrEF and sufficiently prolonged QRS complex, especially those with left bundle branch block (LBBB), may significantly benefit from cardiac resynchronization therapy. Purpose The aim of the study was to analyse the distribution of the QRS durations in patients with HFrEF undergoing ICD implant procedure to better understand the phenomenon of QRS prolongation. Methods All patients undergoing the implant procedure in our centre between January 2017 and December 2021 for HFrEF caused by coronary artery disease (CAD) or dilated cardiomyopathy (DCM) were analysed for the inclusion into the study. The exclusion criteria were (1) coincidence of CAD with DCM, (2) upgrade from any other cardiac rhythm management device, (3) unavailability of the ECG recording or ECG recording with insufficient quality before the implant procedure, (4) more than one ventricular premature beat in the recording. The study used automatically measured QRS duration by Mortara EKG machines (299 recordings with ELI350, 98 with ELI380, and 10 with ELI250). Statistical analysis was performed in R software [1] with the function locmodes for the visualisation of probability density and excess mass test [2] for assessing statistical significance, both from the multimode package. Results The study included 407 patients. In 113 patients with DCM and 177 patients with CAD, the implantation was based on primary prevention (PP) indications, and 24 and 93 patients with DCM and CAD were implanted for secondary prevention (SP) indications. The distribution of QRS durations in the CAD-PP, as well as CAD-SP was unimodal (p=ns). In the DCM-PP group, the distribution was bimodal (p=0.012), in the DCM-SP group, the trend was non-significantly bimodal (p=0.076). Both DCM groups taken together had clearly bimodal distribution (p=0.002 – probability density curve according to locmodes function in the figure). The values between 139 and 142 ms were not present in this group. Below this border zone, two other patients fulfilled the criteria of LBBB, both with the duration close to the border zone (137 and 138 ms). Above this zone, 8 patients had right bundle branch block, the rest had LBBB. Conclusions Bimodal distribution of QRS duration values in patients with DCM supports the idea of sudden change of left bundle conduction rather than slow progression of local changes. In CAD, scars and other local impairments in conduction may hide these changes and no clear border zone can be set. With the well-known differences in the measurements of main ECGmachine manufacturers, criteria for bundle branch block in DCM could be set with high accuracy. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Charles University Research Program “Cooperatio – Cardiovascular Science” and the Ministry of Health of the Czech Republic Conceptual Development of Research Organization

Cardiac Contractility Modulation: A Technical Review.

Therapeutic options for the management of systolic congestive heart failure involving newer implantable device technologies that were not previously available now exist. Cardiac contractility modulation (CCM) has been shown to benefit patients with class III systolic heart failure with an ejection fraction of 25%-45% not indicated for biventricular pacing. Despite the increased use of CCM, there is a significant knowledge deficit in the general electrophysiology community regarding its clinical management. This significantly relates to the different functional characteristics of CCM compared to those encountered in traditional cardiac rhythm management devices. Improved evaluation and troubleshooting of CCM for therapeutic effect will benefit from advanced education. The goal of this review is to present pertinent technical aspects relating to CCM therapy management in a simplified fashion, all the while providing a clinical context to facilitate greater expertise.

Quantifying the Impact of COVID-19 “Lockdown” on Physical Activity in Children and Adults with Implanted Cardiac Rhythm Devices: A Single Center Experience Using Cardiac Rhythm Device Accelerometer Data

Background: In response to the COVID-19 pandemic, the US states of New York and New Jersey instituted a “lockdown” that closed schools and most businesses except for essential services. The public was urged to remain at home. The 78-day lockdown period extended from 22 March 2020 to 6 June 2020. We sought to evaluate the impact of COVID-19 lockdown on continuously recorded physical activity in our patients with congenital heart disease with implanted cardiac rhythm management (CRM) devices—pacemakers (PPM), defibrillators (ICD) and implantable loop recorders (ILR) enabled with accelerometers that translate motion into a measure of active hours/day. Methods: All patients from our congenital CRM database with accelerometer-enabled devices who had stable cardiac status residing in NY and NJ were included. Forty-one patients met the inclusion criteria; the median age was 29.6 years (range 7–60); 54% female; 23 ICD, 15 PPM and 3 ILR. The patient activity was averaged for the 2 months prior to lockdown, during the lockdown, and the 2 months afterward. Paired t-tests were used to compare activity before and during lockdown, and before and after lockdown. Each patient served as his/her own control. Results: Active hours/day decreased by a mean of 32% (±27%) from baseline (p &lt; 0.001). A total of 32 patients experienced a decline, 6 had no change and 3 had an increase. Active hours rebounded after lockdown and were unchanged compared to pre-lockdown levels. Conclusions: The COVID-19 lockdown in NY/NJ during the Spring of 2020 resulted in a significant drop in active hours/day in children and adults with congenital heart disease. Active hours/day rebounded to baseline after restrictions were lifted.

Body Image and Adjustment among Patients with Heart Rhythm Management Devices following Cardiac Rehabilitation Program: A Randomized, Controlled Clinical Trial.

Introduction: Heart rhythm management devices save patients' lives. However, they may cause problems with the patient's perspective of their body image. Therefore, given the significance of the heart function and cardiac rehabilitation, this study was conducted to investigate and compare the effect of the cardiac rehabilitation program on adjustment and body image among patients who use heart rhythm management devices.Methods: This two-group clinical trial was conducted with 100 patients who used various heart rhythm management devices. The patients were randomly assigned into either the control group or intervention group (50 patients in each group) via four triad blocks. The intervention was 16 sessions of the cardiac rehabilitation program and 4 telephone follow-ups over twelve weeks. Data was gathered before the intervention and both eight and twelve weeks after the intervention using the psychosocial adjustment to illness scale and the body image and relationships scale.Findings: The majority of the patients were male and in the age range of 40-60 years. Before the intervention, no statistically significant differences were reported between the groups in terms of adjustment control = 68.13 ± 9.1, intervention = 67.13 ± 4.6) and body image (control = 93.14 ± 8.5, intervention = 91.16 ± 8.4) (P>0.5). However, in the intervention group, with each of three devices (pacemaker, ICD, CRT), significant improvements were observed in all aspects of adjustment (16.7 ± 9.3, 25.3 ± 9.5, 20.6 ± 10.3) and body image (45.50 ± 9.80, 55.10 ± 8.80, 42.90 ± 6.10) over time respectively (P<0.001).Conclusion: The effectiveness of the cardiac rehabilitation program in improving the body image was reported in this study. Therefore, the cardiac rehabilitation program can have a vital role in improving body image and adjustment among patients who use various cardiac rhythm management devices.

Activity During the COVID-19 Pandemic in Children with Cardiac Rhythm Management Devices.

Decreased physical activity is associated with cardiovascular, metabolic and mental health disease. While decreases in physical activity during the COVID-19 pandemic have been described in the general population, there is a paucity of data regarding children with underlying cardiovascular disease. We hypothesized there would be a decrease in physical activity at the onset of the COVID-19 pandemic. Performed a single-center, retrospective cohort study of children aged < 19 years with cardiac rhythm management devices. Patients were included if they had device-measured physical activity data from > 80% of dates from February 3, 2020 through June 30, 2020. Patients with significant neurologic/neuromuscular disease were excluded. We identified 144 patients with a median age of 15.4 years. 47% were female. 34% had congenital heart disease, 20% had cardiomyopathy, 19% had an inherited arrhythmia syndrome and 5% had atrioventricular block without congenital heart disease. 47% of patients had an implantable loop recorder, 29% had a permanent pacemaker and 24% had an implantable cardioverter-defibrillator. We observed a significant decrease in device-measured physical activity from baseline (February 3–March 9), with up to a 21% decrease in physical activity during mid-March through early May. Activity levels returned to pre-pandemic levels in June. Physical activity sharply declined in children with cardiac rhythm management devices at the onset of the COVID-19 pandemic. These data highlight the importance of finding strategies to maintain physical activity during the current pandemic and future public health crises.

Review of the Safety of Bipolar Radiofrequency Ablation in Patients with Chronic Pain with Implantable Cardiac Rhythm Management Devices

Chronic pain, especially low back pain and hip pain, has been a growing public health concern that affects over 100 million Americans annually. Radiofrequency ablation (RFA) has distinct advantages over other chronic pain management modalities and its use has been increasing over the past decade. Among the growing population with comorbid conduction disorders and persistent pain, RFA and its potential interference with implantable cardiac devices is of concern.RFA is becoming a foundational element of persistent pain management and has been shown to be effective in a multitude of chronic pain syndromes. Cardiac implantable electronic devices (CIED), such as cardiac pacemakers or implantable cardioverter defibrillators, have been used in the treatment of cardiac conduction diseases for a number of decades. With our aging population, these diseases have increased in both incidence and prevalence. Chronic pain and cardiac conduction diseases are both common in our increasingly aging population. This study aims to determine if the literature supports the hypothesis that patients with CIEDs can safely use RFA with minimal to no interaction. Systematic assessment of literature with a modified approach with bipolar RFA. A narrative review with systematic assessment of the literature was carried out. In this review, we included randomized controlled trials (RCTs), open non-randomized control studies, prospective studies, retrospective studies, case series, and case reports. All types of radiofrequency utilized for pain management including pulsed and conventional were included. Outcome measures included interactions between the cardiovascular implantable electronic device (CIED) and radiofrequency ablation (RFA), adverse events, RFA efficacy in treating the pain using pain scores, and other complications. Our search criteria yielded 4 studies for inclusion, with inclusion of 33 patients and 71 bipolar radiofrequency for treatments. No adverse events or interactions occurred between the bipolar radiofrequency device and the implanted cardiac devices in any of these patients. Bipolar radiofrequency was utilized in all patients (n = 33). Overall there were no complications or malfunctions. Small sample size, narrative review. This study provides evidence that bipolar RFA can be safely used in patients with CIEDs for chronic pain provided that proper precautions are employed. Considerations for safe use are provided.

Utilization and programming of an automatic MRI recognition feature for cardiac rhythm management devices.

BackgroundCardiac implantable electronic devices (CIED)—ie, pacemakers, implantable cardioverter-defibrillators, and cardiac resynchronization therapy devices—have recently been designed to allow for patients to safely undergo magnetic resonance imaging (MRI) when specific programming is implemented. MRI AutoDetect is a feature that automatically switches CIED’s programming into and out of an MR safe mode when exposed to an MRI environment.ObjectiveThe purpose was to analyze de-identified daily remote transmission data to characterize the utilization of the MRI AutoDetect feature.MethodsHome Monitoring transmission data collected from MRI AutoDetect–capable devices were retrospectively analyzed to determine the workflow and usage in patients experiencing an MRI using the MRI AutoDetect feature.ResultsAmong 48,756 capable systems, 2197 devices underwent an MRI using the MRI AutoDetect feature. In these 2197 devices, the MRI AutoDetect feature was used a total of 2806 times with an average MRI exposure of 40.83 minutes. The majority (88.9%) of MRI exposures occurred on the same day as the MRI AutoDetect programming. A same day post-MRI exposure follow-up device interrogation was performed 8.6% of the time. A device-related complaint occurred within 30 days of the MRI exposure in 0.25% of MRI exposures using MRI AutoDetect but with no adverse clinical outcome.ConclusionAs a result of automation in device programming, the MRI AutoDetect feature eliminated post-MRI device reprogramming in 91.4% of MRI exposures and, while less frequent, allowed for pre-MRI interrogations prior to the day of the MRI exposure—reducing resource utilization and creating workflow flexibility.

Interrupted versus uninterrupted anticoagulation for cardiac rhythm management device insertion

Interrupted versus uninterrupted anticoagulation for cardiac rhythm management device insertion

Challenges in activation of remote monitoring in patients with cardiac rhythm devices during the coronavirus (COVID-19) pandemic

BackgroundRemote monitoring (RM) technology embedded in cardiac rhythm devices permits continuous monitoring of device function, and recording of selected cardiac physiological parameters and cardiac arrhythmias and may be of utmost utility during Coronavirus (COVID-19) pandemic, when in-person office visit for regular follow-up were postponed. However, patients not alredy followed-up via RM represent a challenging group of patients to be managed during the lockdown. MethodsWe reviewed patient files scheduled for an outpatient visit between January 1, 2020 and May 11th, 2020 to assess the proportion of patients in whom RM activation was possible without office visit, and compared them to those scheduled for visit before the lockdown. ResultsDuring COVID-19 pandemic, RM activation was feasible in a minority of patients (7.8% of patients) expected at outpatient clinic for a follow-up visit and device check-up. This was possible in a good proportion of complex implantable devices such as cardiac resynchronization therapy and implantable cardioverter defibrillator but only in a minority of patients with a pacemaker the RM function could be activated during the period of restricted access to hospital. ConclusionsOur experience strongly suggest to consider the systematic activation of RM function at the time of implantation or – by default programming - in all cardiac rhythm management devices.

Transvenous Phrenic Nerve Stimulation Impedance Decrease Prior to Haert Failure Hospitalization

Introduction The remedē System (Respicardia, Inc., Minnetonka, MN), a transvenous phrenic nerve stimulation (TPNS) device that treats central sleep apnea, consists of an implantable pulse generator and a stimulation lead. Stimulation captures the phrenic nerve to contract the diaphragm and expand the lungs similar to normal inspiration. Stimulation lead impedance is checked by the TPNS device to ensure proper therapy delivery. Changes in impedance are constantly evaluated by the system, which then adjusts stimulation current to maintain effective therapy. Patients who experience acute decompensated heart failure (ADHF) retain excess fluid with resultant reduction in thoracic impedance. Hypothesis Thoracic impedance changes due to ADHF can be detected by TPNS lead measurements. Methods A 73 yo male patient with a TPNS system implanted as part of the remedē System Pivotal Trial was hospitalized with ADHF. TPNS device data was examined pre and post hospitalization to asses changes in lead and transthoracic impedance. Results The patient was hospitalized with ADHF for administration of IV diuretic therapy following 3-4 weeks of progressively worsening dyspnea and weight gain. Daily mean lead impedances started to decrease 3 weeks prior to the admission, starting near 750 ohms and reaching a nadir 50 ohms 3 weeks prior, dropping quickly to Conclusion HF decompensation results in decreased lead impedance due to fluid accumulation, but the TPNS device's constant current feature maintains stimulation therapy, as this case demonstrates. While at the present time the system does not alert for potential HF decompensation, consistent detection of impedance changes during HF events should allow TPNS devices to serve as diagnostic tools similar to other cardiac rhythm management (CRM) devices. If HF diagnostics are embedded in future versions of TPNS systems, HF monitoring may be available to patients who otherwise do not qualify for CRM devices. Additional diagnostic power may be achieved by integrating metrics of sleep quality that can be detected by TPNS systems.

Cardiac Electronic Devices: Future Directions and Challenges.

Cardiovascular implantable electronic devices (CIEDs) are essential management options for patients with brady- and tachyarrhythmias or heart failure with concomitant optimal pharmacotherapy. Despite increasing technological advances, there are still gaps in the management of CIED patients, eg, the growing number of lead- and pocket-related long-term complications, including cardiac device–related infective endocarditis, requires the greatest care. Likewise, patients with CIEDs should be monitored remotely as a part of a comprehensive, holistic management approach. In addition, novel technologies used in smartwatches may be a convenient tool for long-term atrial fibrillation (AF) screening, especially in high-risk populations. Early detection of AF may reduce the risk of stroke and other AF-related complications. The objective of this review article was to provide an overview of novel technologies in cardiac rhythm–management devices and future challenges related to CIEDs.