Complications arising from cardiac implantable electrophysiological devices: review of epidemiology, pathogenesis and prevention for the clinician

Atrioventricular Block in the Setting of Immune Myocarditis: A Pragmatic Approach to Diagnosis and Treatment

Immunotherapy has revolutionized cancer treatment in the last decade and has significantly improved patient survival. However, immunotherapy is associated with serious cardiac adverse events including myocarditis and conduction disturbances. In the literature, the mortality rate in patients with immunotherapy-associated myocarditis and complete AV block is reported to be approximately 60%. Current cardio-oncology guidelines provide a series of recommendations for the management of immune myocarditis (IM). However, there is no recommendation on whether or when pacemaker implantation should be performed in the setting of complete AV block associated with myocarditis. This gap in the literature has led to a trend in cardio-oncology practice to implant permanent pacemakers (PPMs) in a significant proportion of patients without waiting for a response to immunosuppressive therapy. However, in a significant proportion of patients undergoing PPM implantation, complete AV block resolves after immunosuppressive therapy. This suggests that in cases of complete AV block in the setting of IM, more robust clues are needed for PPM implantation. This review aims to present algorithms for the management of myocarditis and complete AV block, one of the most lethal complications of immunotherapy, to help fill this gap in the literature.

Trends in the 30-year span of noninfectious cardiovascular implantable electronic device complications in Olmsted County

Background

Cardiac implantable electronic devices (CIEDs), such as permanent pacemakers, implantable cardioverter-defibrillators, and cardiac resynchronization therapy devices, alleviate morbidity and mortality in various diseases. There is a paucity of real-world data on CIED complications and trends.

Objectives

We sought to describe trends in noninfectious CIED complications over the past 3 decades in Olmsted County.

Methods

The Rochester Epidemiology Project is a medical records linkage system comprising records of over 500,000 residents of Olmsted County from 1966 to present. CIED implantations between 1988 and 2018 were determined. Trends in noninfectious complications within 30 days of implantation were analyzed.

Results

A total of 157 (6.2%) of 2536 patients who received CIED experienced device complications. A total of 2.7% of the implants had major complications requiring intervention. Lead dislodgement was the most common (2.8%), followed by hematoma (1.7%). Complications went up from 1988 to 2005, and then showed a downtrend until 2018, driven by a decline in hematomas in the last decade (P < .01). Those with complications were more likely to have prosthetic valves. Obesity appeared to have a protective effect in a multivariate regression model. The mean Charlson comorbidity index has trended up over the 30 years.

Conclusion

Our study describes a real-world trend of CIED complications over 3 decades. Lead dislodgements and hematomas were the most common complications. Complications have declined over the last decade due to safer practices and a better understanding of anticoagulant management.

Frame-rate reduction to reduce radiation dose for cardiac device implantation is safe

Background

Radiation exposure to patient and surgeon during cardiac implantable electrical device (CIED) procedures remains a substantial health hazard to date. Advanced technical options for radiation dose reduction often pose considerable financial hurdles. We propose a near-zero cost, low-effort modification to a clinical x-ray system significantly reducing radiation dose during CIED implantation.

Objective

We aim to evaluate a reduced frame rate protocol in CIED implantation for complication rates and reduction in radiation exposure.

Methods

Starting May 2019, the frame rate during CIED implantations at our hospital was halved from 7.5 frames/s to 3.8 frames/s, and no further technical changes were made. During the following year, 264 patients were operated using this protocol and retrospectively compared with 231 cases implanted in the year before the protocol change, totaling 495 cases. Of these, 17%, 63%, and 19% were single-chamber, dual-chamber, or resynchronization devices, respectively. Incidence of complication prior to hospital discharge was considered the primary endpoint of the analysis. Radiation dose and procedural parameters were secondary endpoints.

Results

There was no increase in complications with the reduced frame rate protocol. Regression analysis further supported that the reduced frame rate radiation protocol was not associated with complication rates. Radiation exposure measured as dose area product was significantly reduced by ∼62% (median 369 [interquartile range 154-1207] cGy·cm² via the reduced frame rate protocol vs median 970 [interquartile range 400-1906] cGy·cm² with the standard frame rate; P < 0.01).

Conclusion

A reduction of frame rate during CIED implantation is safe in terms of complication incidence and effective in terms of reducing radiation exposure.

Trends in the 30-year span of Noninfectious Cardiovascular Implantable Electronic Device Complications in Olmsted County

Background

Cardiovascular implantable electronic devices (CIEDs) such as permanent pacemakers, implantable cardioverter-defibrillators, and cardiac resynchronization therapy devices alleviate morbidity and mortality in various diseases. There is a paucity of real-world data on CIED complications and trends.

Objectives

Describe trends in noninfectious CIED complications over the past three decades in Olmsted County.

Methods

The Rochester Epidemiology Project is a medical records linkage system comprising records of over 500,000 residents of Olmsted County from 1966-current. CIED implants between 1988-2018 were determined. Trends in noninfectious complications within 30 days of implant were analyzed.

Results

175 out of 2536 (6.9%) patients who received CIED experienced device complications. 3.8% of the implants had major complications requiring intervention. Lead dislodgement was the most common (2.9%), followed by hematoma (2.1%). Complications went up from 1988 to 2005, then showed a downtrend until 2018, driven by a decline in hematomas in the last decade (p<0.01). Those with complications were more likely to have prosthetic valves. Obesity appeared to have a protective effect in a multivariate regression model. The mean Charlson comorbidity score has trended up over the 30 years.

Conclusions

Our study describes a real-world trend of CIED complications over three decades. Lead dislodgements and hematomas were the most common complications. Complications have declined over the last decade due to safer practices and a better understanding of anticoagulant management.

Trends in Cardiovascular Implantable Electronic Device Insertion Between 1988 and 2018 in Olmsted County

OBJECTIVES

This study sought to describe trends in cardiovascular implantable electronic device (CIED) insertion over the past 3 decades in Olmsted County.

BACKGROUND

Trends in CIED insertion in the United States have not been extensively studied.

METHODS

The Rochester Epidemiology Project is a medical records linkage system comprising the records of all residents of Olmsted County from 1966 to the present. CIED insertion between 1988 and 2018 was determined using International Classification of Diseases-Ninth Revision, International Classification of Diseases-10th Revision, and Current Procedural Terminology codes. Age- and sex-adjusted incidence rates, adjusted to the 2010 US White population, were calculated. Trends in incidence over time, across age groups, and between sex are estimated using Poisson regression models.

RESULTS

The age- and sex-adjusted incidence of device implants for the study period were as follows: overall CIED: 82.4 (95% CI: 79.2-85.6); permanent pacemaker (PPM): 62.9 (95% CI: 60.0-65.7); implantable cardioverter-defibrillator (ICD): 14.0 (95% CI: 12.6-15.3); and cardiac resynchronization therapy (CRT): 5.6 (95% CI: 4.7-6.4) per 100,000 per year. The overall incidence of CIED insertion increased between 1988 to 1993 and 2000 to 2005 and then decreased between 2000 to 2005 and 2012 to 218 (P < 0.0001). PPM and ICD insertion incidence followed these trends, whereas the incidence of CRT insertion increased between 2000 to 2005 and 2012 to 2018. CIED insertion incidence increased with age (P < 0.0001). CIED insertion incidence was greater in men (116.3 vs 57.3 per 100,000 per year in men vs women; P < 0.0001). The overall survival of CRT recipients improved (P = 0.0044).

CONCLUSIONS

The incidence values for PPM and ICD implants are decreasing, while the incidence of CRT implants is increasing. CIEDs are increasingly inserted in the elderly, men, and patients with higher comorbidities.

Pacemaker lead related myocardial perforation

Permanent pacemaker (PPM) insertion is widely used to treat cardiac rhythm disorders; approximately 600,000 pacemakers are implanted annually in the US (Wood and Ellenbogen, 2002). Almost 9% of patients who receive a permanent pacemaker, however, experience a variety of medical complications such as infections, battery problems, programming issues, lead migration, or lead fracture (Greenspon et al., 2012). Moreover 1-2% of these patients will encounter severe lead-related problems within 30 days of their pacemaker insertion (Kirkfeldt et al., 2014; Kiviniemi et al., 1999). In this report, we focus on an uncommon but serious complication of PPM insertion: right ventricular lead perforation leading to a pericardial effusion. Although lead perforation is a relatively rare occurrence, this event can be life-threatening, and should be considered in the differential diagnosis when patients present to the emergency department (ED) with relevant symptoms and recent PPM insertion. Specifically, patients who experience complications from pacemaker insertion may present to the ED with a variety of symptoms such as chest pain, syncope, dyspnea, or even dizziness (Squire and Niemann, 2006). Pacemaker complications include pneumothorax, pleural and/or pericardial effusions, and infection, placing the patient at serious risk for significant harm (Squire and Niemann, 2006; Shingaki et al., 2015). The evaluation of a lead-related issue typically involves chest radiography to visualize abnormal lead placement and check for a pneumothorax or pleural effusion, and a 12‑lead electrocardiogram (ECG) to detect pacing errors. We present the case of a patient who presented to the ED three days after his pacemaker insertion with chest pain and dyspnea; he was subsequently diagnosed with a lead perforation into the pericardial space resulting in a pericardial effusion.

Heparin-mediated antibiotic delivery from an electrochemically-aligned collagen sheet

BACKGROUND

Implantable medical devices and hardware are prolific in medicine, but hardware associated infections remain a major issue.

OBJECTIVE

To develop and evaluate a novel, biologic antimicrobial coating for medical implants.

METHODS

Electrochemically compacted collagen sheets with and without crosslinked heparin were synthesized per a protocol developed by our group. Sheets were incubated in antibiotic solution (gentamicin or moxifloxacin) overnight, and in vitro activity was assessed with five-day diffusion assays against Pseudomonas aeruginosa. Antibiotic release over time from gentamicin-infused sheets was determined using in vitro elution and high performance liquid chromatography (HPLC).

RESULTS

Collagen-heparin-antibiotic sheets demonstrated larger growth inhibition zones against P. aeruginosa compared to collagen-antibiotic alone sheets. This activity persisted for five days and was not impacted by rinsing sheets prior to evaluation. Rinsed collagen-antibiotic sheets did not produce any inhibition zones. Elution of gentamicin from collagen-heparin-gentamicin sheets was gradual and remained above the minimal inhibitory concentration for gentamicin-sensitive organisms for 29 days. Conversely, collagen-gentamicin sheets eluted their antibiotic load within 24 hours. Overall, heparin-associated sheets demonstrated larger inhibition zones against P. aeruginosa and prolonged elution profile via HPLC.

CONCLUSION

We developed a novel, local antibiotic delivery system that could be used to coat medical implants/hardware in the future and reduce post-operative infections.

Strategies to Promote Long-Term Cardiac Implant Site Health

In the past several decades there has been a continuous growth in the field of cardiac implantable electronic devices (CIED) implantation procedures as well as their technological development. CIEDs utilize transvenous leads that are introduced into the heart via the axillary, subclavian, or cephalic veins, as well as a devices generator that is implanted in a subcutaneous pocket, typically in the pre-pectoral region. Despite this significant improvement, complication rates range from 1-6% with current implant tools and techniques. In this review we will discuss the three central parts of the CIED implantation procedure, their impact on implantation site, infections, and possibilities for its prevention.

Causes of Failure to Capture in Pacemakers and Implantable Cardioverter-defibrillators

The number of patients with implantable electronic cardiac devices is continuously increasing. As more pacemakers and implantable cardioverter-defibrillators (ICDs) are being placed, a basic understanding of some troubleshooting for devices is becoming essential. Loss of capture can be an emergent presentation for an unstable patient and can be encountered intermittently in hospitalized patients. There are many causes for a loss of capture, with the timing of the implant having a high correlation with certain causes over others. The most common acute cause just after the insertion procedure is lead dislodgement or malposition. In comparison, an increase in the required threshold promoting a loss of capture can happen after months to years of insertion of the pacemaker or ICD. This change can be due to a cardiomyopathy, fibrosis medications, metabolic imbalance, lead fracture, or an exit block. Loss of capture can also occur from external electrical stimuli and inappropriate pacemaker or ICD settings. Further, there are also potential noncardiac causes, such as medications, electrolyte imbalance, and acidemia. A knowledge of these factors is essential for health care providers, given the morbidity and mortality that can potentially be associated with device-related issues, especially in patients who are dependent on the included pacing function.

Mutant KCNJ3 and KCNJ5 Potassium Channels as Novel Molecular Targets in Bradyarrhythmias and Atrial Fibrillation

BACKGROUND

Bradyarrhythmia is a common clinical manifestation. Although the majority of cases are acquired, genetic analysis of families with bradyarrhythmia has identified a growing number of causative gene mutations. Because the only ultimate treatment for symptomatic bradyarrhythmia has been invasive surgical implantation of a pacemaker, the discovery of novel therapeutic molecular targets is necessary to improve prognosis and quality of life.

METHODS

We investigated a family containing 7 individuals with autosomal dominant bradyarrhythmias of sinus node dysfunction, atrial fibrillation with slow ventricular response, and atrioventricular block. To identify the causative mutation, we conducted the family-based whole exome sequencing and genome-wide linkage analysis. We characterized the mutation-related mechanisms based on the pathophysiology in vitro. After generating a transgenic animal model to confirm the human phenotypes of bradyarrhythmia, we also evaluated the efficacy of a newly identified molecular-targeted compound to upregulate heart rate in bradyarrhythmias by using the animal model.

RESULTS

We identified one heterozygous mutation, KCNJ3 c.247A>C, p.N83H, as a novel cause of hereditary bradyarrhythmias in this family. KCNJ3 encodes the inwardly rectifying potassium channel Kir3.1, which combines with Kir3.4 (encoded by KCNJ5) to form the acetylcholine-activated potassium channel ( I_KACh channel) with specific expression in the atrium. An additional study using a genome cohort of 2185 patients with sporadic atrial fibrillation revealed another 5 rare mutations in KCNJ3 and KCNJ5, suggesting the relevance of both genes to these arrhythmias. Cellular electrophysiological studies revealed that the KCNJ3 p.N83H mutation caused a gain of I_KACh channel function by increasing the basal current, even in the absence of m₂ muscarinic receptor stimulation. We generated transgenic zebrafish expressing mutant human KCNJ3 in the atrium specifically. It is interesting to note that the selective I_KACh channel blocker NIP-151 repressed the increased current and improved bradyarrhythmia phenotypes in the mutant zebrafish.

CONCLUSIONS

The I_KACh channel is associated with the pathophysiology of bradyarrhythmia and atrial fibrillation, and the mutant I_KACh channel ( KCNJ3 p.N83H) can be effectively inhibited by NIP-151, a selective I_KACh channel blocker. Thus, the I_KACh channel might be considered to be a suitable pharmacological target for patients who have bradyarrhythmia with a gain-of-function mutation in the I_KACh channel.

Use of MPH hemostatic powder for electrophysiology device implantation reduces postoperative rates of pocket hematoma and infection

BACKGROUND

Surgical site bleeding and infection are potential complications after electrophysiology (EP) device implantation procedures. To date, there is a wide variety of tools for management of intraoperative bleeding but it still remains unclear what methods are preferred.

OBJECTIVE

The aim of our study is to compare the rate of complications in patients who underwent cardiac implantable electronic device (CIED) implantation utilizing MPH hemostatic powder to the rate of complications in those patients who underwent standard procedure protocol without MPH hemostatic powder.

METHODS

In our study, a new plant-derived microporous polysaccharide hemostatic powder (Arista) was used. A total of 283 consecutive patients were retrospectively studied to assess the rate of complications in patients who underwent CIED implantation with MPH hemostatic powder (n = 77, MPH hemostatic powder) and without (n = 206, no MPH hemostatic powder). Patients were followed for 12 months.

RESULTS

The MPH hemostatic powder group of patients had a lower complication rate when compared to no MPH hemostatic powder, 0.3% vs. 1.7% (p < .05), respectively. The rate of device implantation site MPH hematoma in the MPH hemostatic powder group was 0.4%, versus 0.9% in the other group. There were no postoperative infections in the MPH hemostatic powder group versus 3.2% infections in the other group. The main predictor of increased risk of post-procedural complication was the usage of anticoagulation with a hazard ration of 2.7.

CONCLUSION

Using MPH hemostatic powder for post-procedural hemostasis was shown to result in a significant reduction in the rate of overall post-procedural complications (a composite endpoint of hematoma and infections), and a trend in reduction of the infections rates and device implantation site hematoma rates.

The prevention, screening and treatment of congenital heart block from neonatal lupus: a survey of provider practices

Objective

To survey an international sample of providers to determine their current practices for the prevention, screening, and treatment of congenital heart block (CHB) due to maternal Ro/SSA antibodies.

Methods

A survey was designed by the organizing committee of the 9th International Conference of Reproduction, Pregnancy and Rheumatic Diseases. It was sent to attendants of the conference and authors of recent publications or abstracts at ACR 2012, 2013 or 2014 on rheumatic diseases and pregnancy.

Results

In anti-Ro/SSA positive women, 80% of 49 respondents recommended screening by serial fetal echocardiogram (ECHO), with most starting at week 16 (59%) and stopping at week 28 (25%), although the time to stop varied widely. For women without a prior infant with neonatal lupus, respondents recommend every other week (44%) or weekly (28%) fetal ECHOs. For women with a prior infant with neonatal lupus, 80% recommend weekly fetal ECHOs. To prevent CHB, HCQ was recommended by 67% of respondents and most would start pre-pregnancy (62%). Respondents were asked about medications to treat varying degrees of CHB in a 20-week pregnant, anti-Ro and La positive SLE patient. For first degree, respondents recommended starting dexamethasone (53%) or HCQ (43%). For second degree, respondents recommended starting dexamethasone (88%). For third degree, respondents recommended starting dexamethasone (55%) or IVIg (33%), although 27% would not start treatment.

Conclusion

Despite the absence of official guidelines, many physicians with a focus on pregnancy and rheumatic disease have developed similar patterns in the screening, prevention and treatment of CHB.

Microbiological diagnosis of device-related biofilm infections

Medical device-related infections cause undue patient distress, increased morbidity and mortality and pose a huge financial burden on healthcare services. The pathogens are frequently distributed heterogeneously in biofilms, which can persist without being effectively cleared by host immune defenses and antibiotic therapy. At present, there is no 'gold standard' available to reveal the presence of device-related biofilm infections. However, adequate sample collection and logistics, standardised diagnostic methods, and interpretation of results by experienced personnel are important steps in efficient diagnosis and treatment of these infections. The focus of this mini review is on prosthethic joint and cardiovascular implantable device infections, which exemplify permanent devices that are placed in a sterile body site. These device-related infections represent some of the most challenging in terms of both diagnosis and treatment.