Pacemaker insertion

Takotsubo cardiomyopathy following pacemaker insertion complicated with polymorphic ventricular tachycardia: a case report

BACKGROUND

Takotsubo cardiomyopathy is a novel form of rapidly reversible heart failure occurring secondary to a stressor that mimics an acute coronary event. The underlying etiology of the stressor is highly variable and can include medical procedures. Pacemaker insertion is an infrequent cause of Takotsubo cardiomyopathy.

CASE PRESENTATION

An 86-year-old Caucasian woman underwent an uncomplicated pacemaker insertion for symptomatic complete heart block in the background of slow atrial fibrillation. A transient episode of polymorphic ventricular tachycardia was noted on day 1 following the procedure; however, her pacemaker was checked and, as she remained stable, she was discharged home. She presented again 5 days later with symptomatic heart failure. Chest X-ray confirmed pulmonary edema. Echocardiography confirmed new onset severe left ventricle dysfunction. Pacemaker checks were normal and lead placement was confirmed. Though her troponin I was elevated, her coronary angiogram was normal. Contrast enhanced echocardiography suggested apical ballooning favoring Takotsubo cardiomyopathy. She was treated for heart failure and made a good recovery. Her follow-up echocardiography a month later showed significant improvement in left ventricle function.

CONCLUSIONS

Takotsubo cardiomyopathy is mediated by a neuro-cardiogenic mechanism due to hypothalamic-pituitary-adrenal axis activation. It generally has a good prognosis. Complications though uncommon, can occur and include arrhythmias. Pacemaker insertion as a precipitant stressor is an infrequent cause of Takotsubo cardiomyopathy. As pacemaker insertions are more frequent in the elderly age group, this phenomenon should be recognized as a potential complication.

Ventricular tachyarrhythmia treatment and prevention by subthreshold stimulation with stretchable epicardial multichannel electrode array

The implantable cardioverter-defibrillator (ICD) is an effective method to prevent sudden cardiac death in high-risk patients. However, the transvenous lead is incompatible with large-area electrophysiological mapping and cannot accommodate selective multichannel precision stimulations. Moreover, it involves high-energy shocks, resulting in pain, myocardial damage, and recurrences of ventricular tachyarrhythmia (VTA). We present a method for VTA treatment based on subthreshold electrical stimulations using a stretchable epicardial multichannel electrode array, which does not disturb the normal contraction or electrical propagation of the ventricle. In rabbit models with myocardial infarction, the infarction was detected by mapping intracardiac electrograms with the stretchable epicardial multichannel electrode array. Then, VTAs could be terminated by sequential electrical stimuli from the epicardial multichannel electrode array beginning with low-energy subthreshold stimulations. Last, we used these subthreshold stimulations to prevent the occurrence of additional VTAs. The proposed protocol using the stretchable epicardial multichannel electrode array provides opportunities toward the development of innovative methods for painless ICD therapy.

Computational Analysis of a Multi-Layered Skin and Cardiac Pacemaker Model Based on Neural Network Approach

The presented study discusses the possible disturbing effects of the electromagnetic field of antennas used in mobile phones or WiFi technologies on the pacemaker in the patient's body. This study aims to obtain information on how the thickness of skin layers (such as the thickness of the hypodermis) can affect the activity of a pacemaker exposed to a high-frequency electromagnetic field. This study describes the computational mathematical analysis and modeling of the heart pacemaker inserted under the skin exposed to various electromagnetic field sources, such as a PIFA antenna and a tuned dipole antenna. The finite integration technique (FIT) for a pacemaker model was implemented within the commercially available CST Microwave simulation software studio. Likewise, the equations that describe the mathematical relationship between the subcutaneous layer thickness and electric field according to different exposures of a tuned dipole and a PIFA antenna are used and applied for training a neural network. The main output of this study is the creation of a mathematical model and a multilayer feedforward neural network, which can show the dependence of the thickness of the hypodermis on the size of the electromagnetic field, from the simulated data from CST Studio.

Case report: A rare complication after the implantation of a cardiac implantable electronic device: Contralateral pneumothorax with pneumopericardium and pneumomediastinum

Cardiac implantable electronic devices (CIED) including pacemakers (PM), implantable cardioverter defibrillators (ICD), and cardiac resynchronized therapy (CRT) have become the mainstay of therapy for many cardiac conditions, consequently drawing attention to the risks and benefits of these procedures. Although CIED implantation is usually a safe procedure, pneumothorax remains an important complication and may contribute to increased morbidity, mortality, length of stay, and hospital costs. On the other hand, pneumopericardium and pneumomediastinum are rare but potentially fatal complications. Accordingly, a high degree of awareness about these complications is important. Pneumothorax almost always occurs on the ipsilateral side of implantation. The development of contralateral pneumothorax is uncommon and may be undetected on an initial chest radiograph. Contralateral pneumothorax with concurrent pneumopericardium and pneumomediastinum is much rarer. We describe a rare case of concurrent right-sided pneumothorax with pneumopericardium and pneumomediastinum after left-sided pacemaker implantation and highlight the risk factors, management, and possible ways to prevent the complications.

Pain after pacemaker/ICD implants

A retrospective study of 322 patient experiences of post-operative pain, short term and long term, following a cardiac implantable electronic device (CIED) procedure. Pain from pacemaker and ICD (implantable cardioverter-defibrillator) implant surgery remains a problem both in terms of severity and longevity. There is a subset of patients receiving implants that have severe pain that may be of a long duration. Patient advice needs to be appropriate to these findings. This study illustrates a need for better pain management by physicians, support, and realistic communication with their patients.

Trauma-induced complete pacemaker lead fracture 8 months prior to hospitalization: A case report

Trauma-induced complete lead fracture is a rare complication of pacemaker implantation. Only a few cases have been previously reported. Common treatment included replacement of pacemaker and/or extraction of fractured lead. In this report, however, we describe this unique case of complete traumatic pacemaker lead fracture. The patient had her right-ventricular lead fractured after a bicycle accident and had lived with the fractured lead for 8 months prior to her hospitalization. After examinations, she was treated with a relatively conservative strategy. The pacemaker and fractured lead were left for further observation and follow-up.

Outcomes of intracutaneous sutures in comparison with intracutaneous staples in cardiac implantable-electronic device pocket closure

OBJECTIVE

With the increase in cardiovascular implantable-electronic devices (CIEDs), complications from insertion and healing are also increasing. Therefore, the objective of this study was to compare the intracutaneous stapling method to the absorbable suture technique in terms of complications, procedure time, and pocket closure time.

METHODS

An observational study was conducted over the course of three months on patients with CIED implantation. The patients were divided in two groups according to pocket closure technique. Group 1 included patients with pocket closure using intracutaneous sutures; whereas in Group 2, the pocket was closed by intracutaneous staples. Data were collected regarding patient characteristics and wound problems. The endpoints were wound problems, including early and late wound problems (primary), total procedure time, and the time taken for pocket closure (secondary).

RESULTS

One hundred and nineteen patients and 107 patients were allocated to Group 1 and Group 2, respectively. During the three-month observation period, 27 (22.6%) patients in Group 1 and 13 (12.1%) patients in Group 2 suffered from early wound problems, and the combined primary endpoint reached was statistically significant (p=0.021). Minor and major bleeding events were more common in Group 1 [Odds ratio (OR): 4.49, p=0.024; OR: 0.96, p=0.052]. The time to close the pocket was markedly reduced in Group 2 (7.29±1.42 vs. 3.98±1.19, p<0.001).

CONCLUSION

The rate of early wound problems is higher using intracutaneous sutures; and therefore, intracutaneous staples should be preferred to prevent these problems.

Innovations in Cardiac Implantable Electronic Devices

Cardiac implantable electronic devices (CIEDs) are essential for the management of a variety of cardiac conditions, including tachyarrhythmias, bradyarrhythmias, and medically refractory heart failure (HF). Recent advancements in CIED technology have led to innovative solutions that overcome shortcomings associated with traditional devices or address unmet needs. Leadless pacemakers, subcutaneous implantable cardioverter defibrillators (ICDs), and extravascular ICDs eliminate lead-related complications common with conventional pacemakers or ICDs. Conduction system pacing (His bundle pacing and left bundle branch pacing) is a more physiologic method of pacing and avoids the deleterious consequences associated with long-term right ventricular pacing. For HF-related devices, cardiac contractility modulation is an emerging therapy that bridges a gap for many patients ineligible for cardiac resynchronization therapy and has been shown to improve HF symptoms and decrease hospitalizations and mortality in select patients. Implantable pulmonary artery pressure monitors help guide HF management and reduce hospitalizations. Lastly, new phrenic nerve stimulating devices are being utilized to treat central sleep apnea, a common comorbidity associated with HF. While further long-term studies are still underway for many of these new technologies, it is anticipated that these devices will become indispensable therapeutics in the expanding cardiovascular armamentarium.

Precision medicine in human heart modeling : Perspectives, challenges, and opportunities

Precision medicine is a new frontier in healthcare that uses scientific methods to customize medical treatment to the individual genes, anatomy, physiology, and lifestyle of each person. In cardiovascular health, precision medicine has emerged as a promising paradigm to enable cost-effective solutions that improve quality of life and reduce mortality rates. However, the exact role in precision medicine for human heart modeling has not yet been fully explored. Here, we discuss the challenges and opportunities for personalized human heart simulations, from diagnosis to device design, treatment planning, and prognosis. With a view toward personalization, we map out the history of anatomic, physical, and constitutive human heart models throughout the past three decades. We illustrate recent human heart modeling in electrophysiology, cardiac mechanics, and fluid dynamics and highlight clinically relevant applications of these models for drug development, pacing lead failure, heart failure, ventricular assist devices, edge-to-edge repair, and annuloplasty. With a view toward translational medicine, we provide a clinical perspective on virtual imaging trials and a regulatory perspective on medical device innovation. We show that precision medicine in human heart modeling does not necessarily require a fully personalized, high-resolution whole heart model with an entire personalized medical history. Instead, we advocate for creating personalized models out of population-based libraries with geometric, biological, physical, and clinical information by morphing between clinical data and medical histories from cohorts of patients using machine learning. We anticipate that this perspective will shape the path toward introducing human heart simulations into precision medicine with the ultimate goals to facilitate clinical decision making, guide treatment planning, and accelerate device design.

Surgical Techniques, Complications, and Long-Term Health Effects of Cardiac Implantable Electronic Devices

Cardiovascular implantable electronic device (CIED) has helped with advanced technological improvement in the cardiac field and has been a long-term alternative to medical management. There are different forms of CIEDs such as pacemakers, implantable cardioverter-defibrillators, and cardiac resynchronization therapy. These devices are efficient in establishing near-normal hemodynamics and circulation that ultimately aid physicians to improve the quality of life for their patients. However, there are risk factors that can result in postoperative complications, including infection, lead and pulse generator complications, heart complications, medication-related complications, and psychosocial complications. To ensure optimal outcome of CIED placement, preprocedural measures need to be in place such as matching the right candidate and using appropriate devices. This review aims to highlight the surgical techniques for CIEDs, the associated postoperative complications, and long-term health effects.

Toward Biological Pacing by Cellular Delivery of Hcn2/SkM1

Electronic pacemakers still face major shortcomings that are largely intrinsic to their hardware-based design. Radical improvements can potentially be generated by gene or cell therapy-based biological pacemakers. Our previous work identified adenoviral gene transfer of Hcn2 and SkM1, encoding a "funny current" and skeletal fast sodium current, respectively, as a potent combination to induce short-term biological pacing in dogs with atrioventricular block. To achieve long-term biological pacemaker activity, alternative delivery platforms need to be explored and optimized. The aim of the present study was therefore to investigate the functional delivery of Hcn2/SkM1 via human cardiomyocyte progenitor cells (CPCs). Nucleofection of Hcn2 and SkM1 in CPCs was optimized and gene transfer was determined for Hcn2 and SkM1 in vitro. The modified CPCs were analyzed using patch-clamp for validation and characterization of functional transgene expression. In addition, biophysical properties of Hcn2 and SkM1 were further investigated in lentivirally transduced CPCs by patch-clamp analysis. To compare both modification methods in vivo, CPCs were nucleofected or lentivirally transduced with GFP and injected in the left ventricle of male NOD-SCID mice. After 1 week, hearts were collected and analyzed for GFP expression and cell engraftment. Subsequent functional studies were carried out by computational modeling. Both nucleofection and lentiviral transduction of CPCs resulted in functional gene transfer of Hcn2 and SkM1 channels. However, lentiviral transduction was more efficient than nucleofection-mediated gene transfer and the virally transduced cells survived better in vivo. These data support future use of lentiviral transduction over nucleofection, concerning CPC-based cardiac gene delivery. Detailed patch-clamp studies revealed Hcn2 and Skm1 current kinetics within the range of previously reported values of other cell systems. Finally, computational modeling indicated that CPC-mediated delivery of Hcn2/SkM1 can generate stable pacemaker function in human ventricular myocytes. These modeling studies further illustrated that SkM1 plays an essential role in the final stage of diastolic depolarization, thereby enhancing biological pacemaker functioning delivered by Hcn2. Altogether these studies support further development of CPC-mediated delivery of Hcn2/SkM1 and functional testing in bradycardia models.

Bilateral Pneumothorax Complicating Pacemaker Implantation, due to Puncture of the Left Subclavian Vein and Electrode Perforation of the Right Atrium

Pneumothorax occurs mostly due to needle injury of the pleura when trying to get access to the subclavian vein and rarely due to electrode perforation. The present case report is the first case presented about acute simultaneous iatrogenic bilateral pneumothorax due to puncture of the left subclavian vein and electrode perforation of the atrial wall, the pericardium, and the pleura. Risk factors, and how to avoid these complications, are highlighted, and symptoms, diagnostics, and management of pneumothorax and cardiac perforation are described.

Pacemaker-generated stress fracture of the second rib: a case report

Background

Pocket-related complications following the implantation of cardiovascular implantable electronic devices primarily include pocket hematoma, infection, skin erosion or decubitus, device migration, and Twiddler's syndrome, with other pathologies such as nerve impairment or bone lesions being extremely rarely encountered. We report a case of a 20-year old asthenic, non-athlete female patient presenting with a device-generated fracture of the second rib several months after sub-muscular permanent pacemaker implantation due to repeated bilateral pre-pectoral pocket infections.

Case presentation

A 20-year old female patient was readmitted to our institution 9 months following sub-pectoral implantation of a permanent pacemaker, complaining of severe pocket-related pain, which arose spontaneously in the absence of direct trauma, intense physical activity or vigorous coughing, and was associated with normal day-to-day activity. To rule out a pacemaker re-infection, a native computed tomography and a positron emission tomography—computed tomography of the thorax were performed. Both modalities excluded an infection but showed a healing fracture and a focus of enhanced metabolic activity in the anterolateral part of the right second rib, indicating a non-traumatic or stress fracture of the bone. Consequently, a complete extraction of the pulse generator and both leads was performed and the smallest available single-chamber pulse generator with a single atrial electrode was implanted in the sub-fascial, pre-muscular pocket in the now recovered and uninfected left subclavicular region, alleviating patient’s severe pain symptoms and significantly enhancing her quality of life.

Conclusions

In the absence of direct trauma, intense physical activity or vigorous coughing, we assume that in this asthenic girl a normal day-to-day motion of the right shoulder has persistently forced the sub-muscularly placed pulse generator toward thoracic wall, putting increased repetitive pressure force on the underlying bones, finally causing a fatigue stress fracture of the second rib. In asthenic phenotype patients with small thorax and short subclavicular distance, a sub-muscular pacemaker implantation can potentially cause unique and unexpected pocket-related adverse events necessitating advanced diagnostics and timely treatment.

Intermittent Pacemaker Malfunction Caused by Continuous Compression of the Lead by the Clavicle (Subclavian Crush Syndrome)

Subclavian vein access is still one of the most favoured access options for cardiac implantable electronic device (CIED) implantation. For the physician, the technique is reasonably familiar and easy to carry out. However, this has several potential complications. In this case, we present a late complication of subclavian access. The patient presented with intermittent loss of pacemaker output, which caused him to experience several syncopal events. In the acute setting, we changed the lead polarity and achieved a good outcome. Further management of this situation consisted of removal and replacement of the damaged lead.

Unusual Delayed Complication of Pacemaker Leads

We present three patients who complained of chest pain secondary to displaced pacemaker leads. They underwent evaluation in the emergency room multiple times for chest pain. Imaging was useful to diagnose misplaced ventricular leads of the pacemaker. The patients needed a pericardial window for the extraction of leads and repair of the heart defect. The perioperative course was managed with a multidisciplinary team of cardiologists and electrophysiologists.

Aortic Valve Calcification as a Predictor of Post-Transcatheter Aortic Valve Replacement Pacemaker Dependence

Background

Atrioventricular block requiring permanent pacemaker (PPM) implantation is a common complication of transcatheter aortic valve replacement (TAVR). The mechanism of atrioventricular (AV) block during TAVR is not fully understood, but it may be due to the mechanical stress of TAVR deployment, resulting in possible injury to the nearby compact AV node. Aortic valve calcification (AVC) may worsen this condition and has been associated with an increased risk for post-TAVR PPM implantation. We performed a retrospective analysis to determine if AVC is predictive for long-term right ventricular (RV) pacing in post-TAVR pacemaker patients at 30 days.

Methods

A total of 262 consecutive patients who underwent TAVR with a balloon-expandable valve were analyzed. AVC data were derived from contrast-enhanced computed tomography and characterized by leaflet sector and region.

Results

A total of 25 patients (11.1%) required post-TAVR PPM implantation. Seventeen patients did not require RV pacing at 30 days. Nine of these 17 patients had no RV pacing requirement within 10 days. The presence of intra-procedural heart block (P = 0.004) was the only significant difference between patients who did not require PPM and those who required PPM but they were not RV pacing-dependent at 30 days. Non-coronary cusp (NCC) calcium volume was significantly higher in patients who were pacemaker-dependent at 30 days (P = 0.01) and a calcium volume of > 239.2 mm³ in the NCC was strongly predictive of pacemaker dependence at 30 days (area under the curve (AUC) = 0.813). Pre-existing right bundle branch block (RBBB) (odds ratio (OR) 105.4, P = 0.004), bifascicular block (OR 12.5, P = 0.02), QRS duration (OR 70.43, P = 0.007) and intra-procedural complete heart block (OR 12.83, P = 0.03) were also predictive of pacemaker dependence at 30 days.

Conclusions

In patients who required PPM after TAVR, quantification of AVC by non-coronary leaflet calcium volume was found to be a novel predictor for RV pacing dependence at 30 days. The association of NCC calcification and PPM dependence may be related to the proximity of the conduction bundle to the non-coronary leaflet. Further studies are necessary to improve risk prediction for long-term RV pacing requirements following TAVR.

Hydrogel Leclanché Cell: Construction and Characterization

A liquid-to-gel based Leclanché cell has been designed, constructed and characterized for use in implantable medical devices and other applications where battery access is limited. This well-established chemistry will provide reliable electrochemical potential over a wide range of applications and the novel construction provides a solution for the re-charging of electrodes in hard to access areas such as an internal pacemaker. The traditional Leclanché cell, comprised of zinc (anode) and manganese dioxide (cathode), conductive carbon powder (acetylene black or graphite), and aqueous electrolyte (NH4Cl and ZnCl2), has been suspended in an agar hydrogel to simplify construction while maintaining electrochemical performance. Agar hydrogel, saturated with electrolyte, serves as the cell support and separator allowing for the discharged battery suspension to be easily replaced once exhausted. Different amounts of active anode/cathode material have been tested and discharge characteristics have been plotted. It has been found that for the same amount of active material, acetylene black batteries have higher energy density compared to graphite batteries. Graphite batteries also discharge faster compared to acetylene black batteries. The results support further development of liquid batteries that can be replaced and refilled upon depletion.

Chest radiographs of cardiac devices (Part 1): Cardiovascular implantable electronic devices, cardiac valve prostheses and Amplatzer occluder devices

Several new innovative cardiac devices have been created over the last few decades. Chest radiographs (CXRs) are the most common imaging investigations undertaken because of their value in evaluating the cardiorespiratory system. It is important for the interpreting radiologist to not only identify these iatrogenic objects but also to assess for their accurate placement, as well as for any complications related to their placement, which may be seen either on the immediate post-procedural CXR or on a follow-up CXR.

Assessment of fatigue in patients with a permanent cardiac pacemaker: prevalence and associated factors

INTRODUCTION

Fatigue is a debilitating symptom of subjective nature which lacks effective therapy. The aim of the study was to assess levels of fatigue and the associated factors among patients with permanent cardiac pacemaker (PCM).

MATERIAL AND METHODS

This was a cross-sectional study carried out in Athens. The study sample consisted of 250 patients with a PCM.

RESULTS

Data indicated moderate to low levels of fatigue. Furthermore, women (median: 24, p = 0.001), those with primary school education (median: 21, p = 0.001), those who were "a little-not at all" informed about PCM (median: 31, p = 0.001), those who had someone to help them in daily activities (median: 23, p = 0.001), those who did not believe that PCM solved their cardiac problem (median: 36, p = 0.001), and those who did not believe that their quality of life was improved (median: 35, p = 0.001) had high levels of fatigue. Moreover, high levels of fatigue were felt by those who characterized themselves as anxious and those who reported to be very anxious about their heart rate and the proper function of PCM (medians: 21.5, 25 and 25 respectively). Additionally, more fatigue was felt by participants who did not smoke after implantation and did not exercise at all (medians: 20 and 24 respectively). Finally, older patients felt more fatigue (rho = 0.248) while the later the implantation device was inserted the more fatigue the patients felt (rho = 0.274).

CONCLUSIONS

The present results will help clinicians to acquire an in-depth knowledge of factors associated with fatigue after implantation.

A combination of rare complications 3 years after a dual-chamber pacemaker implantation

Late perforation of the atrial wall after pacemaker implantation frequently remains asymptomatic but may cause chest pain, dyspnea or syncope. Perforation can also lead to rarer complications such as hemoptysis and pneumopericardium. We present the case of a patient who developed progressive hemoptysis 3 years after a dual-chamber pacemaker implantation. Pacemaker interrogation showed stable impedance of the right atrial lead and stable pacing threshold values. CT revealed perforation of the right atrial wall by the RA-lead with consecutive pneumopericardium and diffuse lung bleeding of the right middle lobe. The patient was hemodynamically stable at all times. The right atrial lead was transvenously extracted and replaced without any further complications.

Permanent pacemaker insertion in patients with conduction abnormalities post transcatheter aortic valve replacement: a review and proposed guidelines

Conduction abnormalities are a common and serious complication of transcatheter aortic valve replacement (TAVR) with well-established predictive factors. Current guidelines are not concrete, leaving several questions unanswered about indications, timing and risks of pacemaker implantation post-TAVR. In this review article, we discuss current guidelines, predictors of pacemaker implantation, clinical implications of this procedure and our recommendations for reducing the pacemaker implantation rate post-TAVR.

Lead displacement due to tension pneumothorax following permanent pacemaker implantation

A 62-year-old female, who had undergone dual chamber pacemaker implantation through left subclavian approach, developed tension pneumothorax of left side. This resulted in shift of entire mediastinum and lead displacement with altered lead parameters. Pacemaker implantation can be complicated by tension pneumothorax in 0.6-5% of cases. Tension pneumothorax can cause mediastinal shift and rarely cause displacement of the leads. In our patient, shift of mediastinum with change of loops and position was associated with change of parameters requiring lead revision. <Learning objective: Pacemaker implantation can be complicated by tension pneumothorax in 0.6-5% of cases. Tension pneumothorax can cause mediastinal shift and rarely cause displacement of the leads. In our patient, shift of mediastinum with change of loops and position was associated with change of parameters requiring lead revision. This clinical scenario is rarely seen and has not been documented before.>.