Trends in service time of pacemakers in the Netherlands: a long-term nationwide follow-up study

Current state of the art and future directions for implantable sensors in medical technology: Clinical needs and engineering challenges

Implantable sensors have revolutionized the way we monitor biophysical and biochemical parameters by enabling real-time closed-loop intervention or therapy. These technologies align with the new era of healthcare known as healthcare 5.0, which encompasses smart disease control and detection, virtual care, intelligent health management, smart monitoring, and decision-making. This review explores the diverse biomedical applications of implantable temperature, mechanical, electrophysiological, optical, and electrochemical sensors. We delve into the engineering principles that serve as the foundation for their development. We also address the challenges faced by researchers and designers in bridging the gap between implantable sensor research and their clinical adoption by emphasizing the importance of careful consideration of clinical requirements and engineering challenges. We highlight the need for future research to explore issues such as long-term performance, biocompatibility, and power sources, as well as the potential for implantable sensors to transform healthcare across multiple disciplines. It is evident that implantable sensors have immense potential in the field of medical technology. However, the gap between research and clinical adoption remains wide, and there are still major obstacles to overcome before they can become a widely adopted part of medical practice.

Development and Validation of a Novel Risk Score for All-Cause Mortality Risk Stratification Prior to Permanent Pacemaker Implantation in Octogenarians or Older

Background and Objectives: The demand for permanent pacemaker (PPM) implantation for extremely old patients is increasing. Prior to implanting PPMs, life expectancy evaluation is essential but difficult. We aimed to develop and validate a scoring system for all-cause mortality risk stratification prior to PPM implantation in patients aged ≥80. Materials and Methods: A total of 210 patients aged ≥80 who received PPM implantation were included. Multivariable analysis was performed to assess the effects of different variables on all-cause mortality in a derivation cohort (n = 100). We developed the MELODY score for stratifying all-cause mortality prior to PPM implantation and tested the scoring system in a validation cohort (n = 102). Results: After 4.0 ± 2.7 years of follow-up, 54 patients (54%) had died. The 0.5-, 1- and 2-year all-cause mortality rates were 7%, 10% and 24%, respectively. The MELODY score based on body mass index <21 kg/m2 (HR: 2.21, 95% CI: 1.06-4.61), estimated glomerular filtration rate <30 mL/min/1.73 m2 (3.35, 1.77-6.35), length of hospitalization before PPM implantation >7 days (1.87, 1.02-3.43) and dyspnea as the major presenting symptom (1.90, 1.03-3.50) successfully distinguished patients at high risk of mortality. Patients with MELODY scores ≥3 had a higher risk of mortality compared to those with MELODY scores <3 (8.49, 4.24-17.00). The areas under the receiver operating characteristic curves in predicting 0.5, 1 and 2 years mortality rates were 0.86, 0.81 and 0.74, respectively. The predictive value of the model was confirmed in a validation cohort. Conclusions: The novel scoring system is a simple and effective tool for all-cause mortality risk stratification prior to PPM implantation in patients aged ≥80.

Cardiac Implantable Electronic Devices: Reoperations and the Competing Risk of Death

BACKGROUND

The use of cardiac implantable electronic devices (CIED), which includes pacemakers, implantable cardioverter-defibrillators (ICD), cardiac resynchronisation therapy pacemakers (CRT-P) and cardiac resynchronisation therapy defibrillators (CRT-D) has increased over the past 20 years, but there is a lack of real world evidence on the longevity of these devices in the older population which is essential to inform health care delivery and support clinical decisions.

METHODS AND RESULTS

We conducted a retrospective cohort study using data from the Australian Government Department of Veterans' Affairs database. The cohort consisted of people who had a CIED procedure between 2005 and 2015. The cumulative risk of generator replacement/reoperations was estimated accounting for the competing risk of death. A total of 16,662 patients were included. In pacemaker recipients with an average age of 85 years, the 5-year risk of reoperation ranged from 2.8% in single chamber, 3.6% in dual chamber to 7.6% in CRT-P recipients, while the 5-year risk of dying with the index pacemaker in situ was 63% in single chamber, 46% in dual chamber and 56% in CRT-P recipients. In defibrillator recipients with an average age of 80 years, the 5-year risk of reoperation ranged from 11% in single chamber, 13% in dual chamber to 24% in CRT-D recipients, while the 5-year risk of dying with the index defibrillator in situ was 46% in single chamber, 40% in dual chamber and 41% in CRT-D recipients.

CONCLUSION

In this cohort of older patients the 5-year risk of generator reoperation was low in pacemaker recipients whereas up to one in four CRT-D recipients would have a reoperation within 5 years.

The ethics of explantation

BACKGROUND

With the increased use of implanted medical devices follows a large number of explantations. Implants are removed for a wide range of reasons, including manufacturing defects, recovery making the device unnecessary, battery depletion, availability of new and better models, and patients asking for a removal. Explantation gives rise to a wide range of ethical issues, but the discussion of these problems is scattered over many clinical disciplines.

METHODS

Information from multiple clinical disciplines was synthesized and analysed in order to provide a comprehensive approach to the ethical issues involved in the explantation of medical implants.

RESULTS

Discussions and recommendations are offered on pre-implantation information about a possible future explantation, risk-benefit assessments of explantation, elective explantations demanded by the patient, explantation of implants inserted for a clinical trial, patient registers, quality assurance, routines for investigating explanted implants, and demands on manufacturers to prioritize increased service time in battery-driven implants and to market fewer but more thoroughly tested models of implants.

CONCLUSION

Special emphasis is given to the issue of control or ownership over implants, which underlies many of the ethical problems concerning explantation. It is proposed that just like transplants, implants that fulfil functions normally carried out by biological organs should be counted as supplemented body parts. This means that the patient has a strong and inalienable right to the implant, but upon explantation it loses that status.

Degradation Behavior, Biocompatibility, Electrochemical Performance, and Circularity Potential of Transient Batteries

Transient technology seeks the development of materials, devices, or systems that undergo controlled degradation processes after a stable operation period, leaving behind harmless residues. To enable externally powered fully transient devices operating for longer periods compared to passive devices, transient batteries are needed. Albeit transient batteries are initially intended for biomedical applications, they represent an effective solution to circumvent the current contaminant leakage into the environment. Transient technology enables a more efficient recycling as it enhances material retrieval rates, limiting both human and environmental exposures to the hazardous pollutants present in conventional batteries. Little efforts are focused to catalog and understand the degradation characteristics of transient batteries. As the energy field is a property-driven science, not only electrochemical performance but also their degradation behavior plays a pivotal role in defining the specific end-use applications. The state-of-the-art transient batteries are critically reviewed with special emphasis on the degradation mechanisms, transiency time, and biocompatibility of the released degradation products. The potential of transient batteries to change the current paradigm that considers batteries as harmful waste is highlighted. Overall, transient batteries are ready for takeoff and hold a promising future to be a frontrunner in the uptake of circular economy concepts.

Predictors of long-term survival prior to permanent pacemaker implantation in octogenarians or older

Background

There is an increased need for permanent pacemaker (PPM) implantation for older patients with multiple comorbidities. The current guidelines recommend that, before implanting PPM, clinicians should discuss life expectancy with patients and their families as part of the decision-making process. However, estimating individual life expectancy is always a challenge.

Aims

We investigated predictors of long-term survival prior to PPM implantation in patients aged 80 or older.

Methods and results

From September 2004 to September 2015, 100 patients aged ≥ 80 years who received PPM implantation were included for retrospective survival analysis. The end point was all-cause mortality. Follow-up duration was 4.0 ± 2.7 years. By the end of the study, 54 patients (54%) had died. Of the 54 who died, 40 patients (74.1%) died of non-cardiac causes. Their survival rates at 1, 2, 3, 5, and 7 years were 90%, 76%, 54%, 32%, and 16%, respectively. Patients with a longer length of hospital stay before PPM implantation (LOS-B) [hazard ratio (HR) 1.03, 95% confidence interval (CI) 1.02–1.05, p < 0.001], estimated glomerular filtration rate (eGFR) < 30 ml/min/1.73 m² (HR 4.07, 95% CI 1.95–8.52, p < 0.001), body mass index (BMI) < 21 kg/m² (HR 2.50, 95% CI 1.16–5.39, p = 0.02), and dyspnea as the major presenting symptom (HR 2.88, 95% CI 1.27–6.55, p = 0.01) were associated with lower cumulative survival.

Conclusions

Longer LOS-B, lower eGFR and BMI, and dyspnea as the major presenting symptom are pre-PPM implantation predictors of long-term survival in patients aged 80 or older.

Remote Monitoring of Implantable Cardioverter-Defibrillators, Cardiac Resynchronization Therapy and Permanent Pacemakers: A Health Technology Assessment

BACKGROUND

Under usual care, people with an implantable cardioverter-defibrillator (ICD), cardiac resynchronization therapy with or without a defibrillator (CRT-D and CRT-P, respectively), or a permanent pacemaker have follow-up in-person clinic visits. Remote monitoring of these devices allows the transfer of the information stored in the device so that it can be accessed by the clinic personnel via a secured website.

METHODS

We completed a health technology assessment, which included an evaluation of clinical benefits and harms, value for money, and patient preferences for remote monitoring of ICDs, CRTs, and permanent pacemakers plus clinic visits compared with clinic visits alone. This is an update of a 2012 health technology assessment. In addition to the eligible randomized controlled trials (RCTs) from the 2012 publication, we included RCTs identified through a systematic literature search on June 1, 2017. We assessed the risk of bias of each study using the Cochrane risk of bias tool and the quality of the body of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. We conducted an economic evaluation to determine the cost-effectiveness of remote monitoring blended with in-clinic follow-up compared to in-clinic follow-up alone in patients with an ICD, a CRT-D, or a pacemaker. We determined the budget impact of blended remote monitoring in patients implanted with ICD, CRT-D, CRT-P, or pacemaker devices from the perspective of the Ontario Ministry of Health and Long-Term Care. To understand patient experiences with remote monitoring, we interviewed 16 patients and family members.

RESULTS

Based on 15 RCTs in patients with implanted ICDs or CRT-Ds, remote monitoring plus clinic visits resulted in fewer patients with inappropriate ICD shocks within 12 to 37 months of follow-up (moderate quality evidence; absolute risk difference -0.04 [95% confidence interval -0.07 to -0.01]), fewer total clinic visits (moderate quality evidence), and a shorter time to detection and treatment of events (moderate quality evidence) compared with clinic visits alone. There was a similar risk of major adverse events (moderate quality evidence).Based on 6 RCTs in patients with pacemakers, remote monitoring plus clinic visits reduced the arrhythmia burden (high quality evidence), the time to detection and treatment of arrhythmias (high quality evidence), and the number of clinic visits (moderate quality evidence]) compared with clinic visits alone. Here again, there was a similar risk of major adverse events (high quality evidence).Results from the economic evaluation showed that among ICD and CRT-D recipients, blended remote monitoring (remote monitoring plus in-clinic follow ups) was more costly (incremental value of $4,354 per person) and more effective, providing higher quality-adjusted life years (incremental value of 0.19), compared to in-clinic follow-up alone. Among pacemaker recipients, blended remote monitoring was less costly (with an incremental saving of $2,370 per person) and more effective (with an incremental value of 0.12 quality-adjusted life years) than with in-clinic follow-up alone. We estimated that publicly funding remote monitoring could result in cost savings of $14 million over the first five years.Participants using remote monitoring reported that these devices provide important medical and safety benefits in managing their heart condition. Remote cardiac monitoring provides patients and their family members with an increased freedom. Their belief that the device will help with earlier detection of technical or clinical problems reduces the amount of stress and distraction their condition causes in their lives.

CONCLUSIONS

Remote monitoring of ICDs, CRT-Ds, and pacemakers plus clinic visits resulted in improved outcomes without increasing the risk of major adverse events compared with clinic visits alone. Remote monitoring is a cost-effective option for patients implanted with cardiac electronic devices. Patients reported positive experiences using remote monitoring, and perceived that the device provided important medical and safety benefits.

Trends in replacement of pacemaker leads in the Netherlands: A long-term nationwide follow-up study

BACKGROUND

Our objective was to investigate trends over time in longevity and reasons for replacement with or without extraction of pacemaker leads after first implantation.

METHODS

Data collected between 1984 and 2006 in the national Dutch pacemaker registry were used. This registry covered 84% of sold leads. First lead replacement with or without extraction of one or more leads implanted with a first pacemaker generator was the endpoint of interest. The time interval of and reason for first replacement were analyzed. A 7-year follow-up interval after first implantation was used to analyze changes over time.

RESULTS

During 22 years of data collection, 138,225 leads were implanted with a first pacemaker generator. Within a mean 5.5 (SD 4.4) years for 7,377 patients one or more leads were extracted for the first time. In total, 8,849 leads (6.4%) were replaced or extracted. The main reasons for first replacement of leads with or without extraction were insulation failures (14.6%), infection (8.8%), displacement (7.6%), or for elective reasons (10.0%). The number of insulation failures peaked during 1991-1995.

CONCLUSIONS

Despite improvements in pacing techniques and experience with cardiac devices, we found that insulation and conductor failures, and complications such as infections, did not diminish over the 20 years of the registry. Continuing attention in clinical practice for the evaluation of these adverse outcomes and maintaining quality registries is warranted, whereas manufacturers should use this information to further improve their devices.