Defect Device Research Articles

Termination of Ventricular Septal Defect Device Closure Due to an Insurmountable Obstruction

Termination of Ventricular Septal Defect Device Closure Due to an Insurmountable Obstruction

Hexagonal Boron Nitride Based Photonic Quantum Technologies.

Hexagonal boron nitride is rapidly gaining interest as a platform for photonic quantum technologies, due to its two-dimensional nature and its ability to host defects deep within its large band gap that may act as room-temperature single-photon emitters. In this review paper we provide an overview of (1) the structure, properties, growth and transfer of hexagonal boron nitride; (2) the creationof colour centres in hexagonal boron nitride and assignment of defects by comparison with ab initio calculations for applications in photonic quantum technologies; and (3) heterostructure devices for the electrical tuning and charge control of colour centres that form the basis for photonic quantum technology devices. The aim of this review is to provide readers a summary of progress in both defect engineering and device fabrication in hexagonal boron nitride based photonic quantum technologies.

Ebstein Anomaly: Insights on Isolated Atrial Septal Defect Device Closure.

Ebstein Anomaly: Insights on Isolated Atrial Septal Defect Device Closure.

Long-Term Outcomes of Percutaneous Trans-catheter Device Closure of Atrial Septal Defects During Teenage Life versus Adulthood

Abstract Aim and Objectives To evaluate the long-term follow up outcome of patients who underwent percutaneous trans-catheter closure of atrial septal defects during teenage life versus adulthood. Patients and Methods The study included 100 patients with secundum type ASD were treated by transcatheter closure of their defects. Two year after the procedure patients included in the study were subjected to thorough history taking, physical examination,12 leads surface electrocardiogram and Holter. Full 2D and Doppler echocardiographic study was performed in addition to Tissue Doppler Assessment of left ventricular function. Results At the 2 years follow up of transcatheter ASD closure, the RVEDD had decreased from 22.93±5.889 mm to 18±4.06 mm(P = 0.000). By comparing 2D echocardiographic parameters between teenagers and adults there was a highly significant difference in RV basal diameter (P = 0.004), RV systolic function (P = 0.000), RA area (P = 0.030). Mean PAP decreased from 18.37±4.796 mmHg to 14.77±4.75 mmHg (P = 0.022). RVSP decreased from 28.9±4.425 mmHg to 15.83±4.17 mmHg (P = 0.000). There was statistically significant difference regarding defect size (P = 0.037), device size (P = 0.038) and Holter findings (P = 0.042) while there was no statistically significant difference between both groups regarding mPAP, device type and ECG. Defect size was larger in adult group ranged from 9 to 33 mm with mean ± SD 15.57 ± 6.57 mm than teenagers ranged from 6 to 22 mm with mean ± SD 13.06 ± 5.18 mm. Also, incidence of arrhythmia in adults was higher than teenagers as follows: PACs was in 7 patients (14 %) in adult group while 3 patients (6 %) had PACs in teenagers group and paroxsymal AF was found in 4 patients (8 %) in adult group while no patients in teenagers develop AF. All the patients had normal sinus rhythm before closure and no one developed arrhythmia until 1 year after closure. 50 % of the patients had normal RV size at the 2-year follow up. Regarding Doppler parameters, mitral E/A ratio (P = 0.000) and lateral E/e' ratio (P = 0.041) had significant difference between adults and teenagers as shown in table (8) mostly related to age. Mitral E/A ratio in adults ranged from 0.7 to 1.5 with mean ± SD 1.06 ± 0.20 while in teenagers ranged from 1.1 to 1.8 with mean ± SD 1.45 ± 0.17. Lateral E/e’ ratio in adults ranged from 3 to 7.9 with mean ± SD 5.43 ± 1.24 while in teenagers ranged from 3 to 7 with mean ± SD 4.94 ± 1.13. Conclusion Transcatheter ASD closure leads to a significant improvement in heart cavity dimensions and RV function and reversal of electrical and mechanical changes. Novel parameters for assessment of RV function are promising and appear to be helpful for the assessment of RV function and its response to correction of volume. Key words: Atrial septal defect, arrhythmia, transcatheter closure, adults, teenagers. Abbreviations and Acronyms 2D: Two-Dimensional 3D:Three-dimensional ASD(s): Atrial septal defect(s) BSA: Body surface area CHDs: Congenital heart defects ECG: Electrocardiogram EF: Ejection fraction FAC: Fractional Area Change LA: Left Atrium mPAP: mean Pulmonary Artery Pressure RA: Right Atrium RAA: Right atrial area RBBB: Right Bundle Branch Block RV : Right Ventricle TEE : TransEsophgyeal Echocardiography TTE : TransThoracic Echocardiography

Pattern of Medical Device Adverse Events in a Tertiary Care Hospital in Northern India: An Ambispective Study.

Knowledge about the pattern of adverse events caused by medical devices (MDs) is limited in India. We aimed to assess the pattern of MD adverse events (MDAEs) in a tertiary hospital in Northern India. This descriptive study was conducted ambispectively at various clinical departments of PGIMER, Chandigarh. We followed the guidelines edged by the Materiovigilance Program of India (MvPI) to conduct this study. The prospective study (PS) was done from January to December 2020, with a concurrent retrospective study (RS) proceeding to 3 years to learn more about the reporting culture, demographics, notification status, risk class of defective devices, and the type of adverse events. We received 224 MDAE in the PS and identified 413 MDAE in the RS. Reporting of adverse events to the national MvPI was negligible in the RS. In the PS, nurses reported the majority of MDAEs (65%), followed by doctors (30%). The occurrence of MDAE was higher in males (PS; 52%, RS; 57%) and age groups between 21 and 30 years (PS; 19.1%, RS; 23.2%) in both studies. MDAEs were frequent in low- to moderate-risk devices (class B: 66%) in the PS, while it was documented only for high-risk devices (class C: 51% and class D: 49%) in the RS. Most of the serious adverse events (SAEs) were reported among moderate to high-risk devices, and an increased frequency of SAE (60.4%) was observed among nonnotified MDs. The overall incidence of near-miss events was 14%. Knowledge of MDAEs and reporting of defective devices to regulatory authorities is essential to prevent further incidence. Adverse events caused by MDs are ubiquitous irrespective of their risk classification, notification status, and patient demographic factors. Accelerated reporting of MDAE by all cadre of healthcare professionals is urgently required to safeguard the health of Indians.

Exploration of Deep Learning Models for Accelerated Defect Property Predictions and Device Design of Cubic Semiconductor Crystals

Exploration of Deep Learning Models for Accelerated Defect Property Predictions and Device Design of Cubic Semiconductor Crystals

Sinus venosus atrial septal defect device closure

ABSTRACT With technical advancements, transcatheter closure of sinus venosus atrial septal defect (SVASD) proves safe and effective, even in developing countries. A 38-year-old male with recurrent palpitations underwent transesophageal echocardiography and cardiac computerized tomography, confirming a 14 mm SVASD with left-to-right shunt. Under GA and mechanical ventilation, we deployed a 19–25 mm ZYPHER-covered peripheral stent using 22 mm × 60 mm Z-Med II Balloon guidance. An angiogram confirmed adequate defect coverage. Postprocedure, occasional ventricular premature contractions and intermittent atrioventricular block were noted on 72-h Holter. Follow-up showed symptom resolution, with transthoracic echocardiography confirming stent placement and no residual shunt, endorsing device closure as a viable alternative to surgery.

Three for one – Cardiac perforations at three sites following atrial septal defect device closure

ABSTRACT The interventional cardiac catheterization for treating congenital heart disease has evolved. Complications following interventional procedures might need emergency surgery as a bailout. Here, we report a case of cardiac perforations in three different sites following device closure of atrial septal defect (ASD). In literature, the major sites of ASD device erosion are at the roof of the right atrium (RA), left atrium (LA), or at the atrial junction with the aorta. In our patient, the device eroded at all three sites: the roof of the LA, RA, and the aorta, causing hemopericardium.

Use of Virtual Reality and 3D Models in Contemporary Practice of Cardiology.

To provide an overview of the impact of virtual and augmented reality in contemporary cardiovascular medical practice. The utilization of virtual and augmented reality has emerged as an innovative technique in various cardiovascular subspecialties, including interventional adult, pediatric, and adult congenital as well as structural heart disease and heart failure. In particular, electrophysiology has proven valuable for both diagnostic and therapeutic procedures. The incorporation of 3D reconstruction modeling has significantly enhanced our understanding of patient anatomy and morphology, thereby improving diagnostic accuracy and patient outcomes. The interactive modeling of cardiac structure and function within the virtual realm plays a pivotal role in comprehending complex congenital, structural, and coronary pathology. This, in turn, contributes to safer interventions and surgical procedures. Noteworthy applications include septal defect device closure, transcatheter valvular interventions, and left atrial occlusion device implantation. The implementation of virtual reality has been shown to yield cost savings in healthcare, reduce procedure time, minimize radiation exposure, lower intravenous contrast usage, and decrease the extent of anesthesia required. These benefits collectively result in a more efficient and effective approach to patient care.

3D printing feasibility of a controlled dynamization device for external circular fixation

Aimto assess the small-scale 3D printing feasibility and cost estimation of a device for controlled dynamization. Materials and MethodThe two-part device previously developed by our research group was printed with a carbon fiber-reinforced nylon filament (Gen3 CarbonX™ PA6+CF, 3DXTECH Additive Manufacturing) by a professional 3D printer (FUNMAT HT, Intamsys). Electricity, material, and labor costs for production in a Brazilian city in the Santa Catarina state were calculated. ResultsThe devices for controlled dynamization were successfully printed in accordance with the planned design and dimensions. Six out of 38 printed devices presented defects in the bolt hole and were discarded. The average printing time per device was 1.9 h. The average electricity, material, and labor costs per printed device were respectively US$0.71, US$13.55, and US$3.04. The total production cost per device reaches approximately US$20 by adding the average cost of defective devices (15 %). Conclusion3D printing of the controlled dynamization device is feasible and its cost seems affordable to most healthcare services, which could optimize the consolidation of diaphyseal fractures and reduce treatment time for patients.

Flexible Bayesian reliability demonstration testing

AbstractThe aim is to demonstrate the reliability of a population at consecutive points in time, where a sample at each current point must prove that at least 100% of the devices function until the next point with a probability of at least . To test the reliability of the population, we flexibilise standard lifetime models by allowing the unknown parameter(s) of the corresponding counting process to vary in time. At the same time, we assign a prior distribution that assumes the parameters to be constant within a certain interval. This flexibilisation has several advantages: it can be applied for all parametric lifetimes; its Markov property allows the efficient derivation of the number of defective devices, even for a large number of testing times; and the inference is less certain and hence more realistic and leads to less frequent acceptance of poor quality populations. On the other hand, the inference is stabilised by the informative prior. Based on the flexibilisation of the homogeneous Poisson process (HPP), we derive acceptance sampling plans to test the future reliability of a population. Applying the zero failure sampling plans on simulations of Weibull processes shows their good frequentist properties and their robustness. In the case of utility meters subject to German regulations (Mess‐ und Eichverordnung (MessEV). 2014: 2010–2073.), application of the derived sequential sampling plans when the conditions of these plans are met can lead to an extension of the verification validity period. These sampling plans protect the consumer better than those from an HPP and are still cost efficient.

Silane Doping for Efficient Flexible Perovskite Solar Cells with Improved Defect Passivation and Device Stability.

In this work, doping 3-amino-propyl triethoxysilane (APTES) into a perovskite precursor is proven to be an effective strategy, which can passivate crystal defects, control the crystallization rate, and improve the morphology. APTES can form oligomers through hydrolysis and a condensation reaction, thus blocking the invasion of external water molecules. In addition, the lone pair electrons on the N atom in the amino group of APTES form a coordination bond with perovskite by sharing the empty 6p orbital on Pb2+, which can effectively passivate the defects of the film and realize a highly uniform and dense perovskite film with preferential crystal growth orientation. The film exhibits high (110) crystal plane orientation and long carrier lifetime and mobility, which improves the performance of flexible perovskite solar cells. Using this approach, the champion device presents an optimal power conversion efficiency of 19.84% with much promoted air stability. Moreover, the efficiency of flexible devices does not decrease after maximum power point irradiation for 360 s.

Late Presentation of Pulmonary Hypertension Crisis Concurrent with Atrial Arrhythmia after Atrial Septal Defect Device Closure

Background: ASD occurs when there is a septal defect between the right and left atria, resulting in a left-to-right shunt that increases the volume of the right heart and pulmonary circulation. Increased pulmonary resistance can lead to pulmonary hypertension (PH), resulting in progressive deterioration of right ventricular function, leading to right heart failure and death. Prolonged elevation of atrial pressure induces progressive atrial dilatation and electrophysiological remodelling. Together with autonomic modulation, this leads to atrial arrhythmias (AAs). Patients with significant shunts leading to ventricular volume overload are considered for ASD closure. However, in some cases, PH occurs after ASD closure.  Case Presentation: We report a 21 yo man diagnosed with ASD Secundum Post Closure with Device (September 1th, 2023) and Pulmonary Hypertension Crisis. The left atria (LA), right atria (RA) and right ventricle (RV) were dilated. We also found moderate mitral regurgitation, severe tricuspid regurgitation, and mild to moderate pulmonary regurgitation. There was a decline in systolic function in the right ventricle, and grade III diastolic dysfunction in left ventricle. There was a well-seated device with no residual shunt on interatrial septal. The pulmonary arteries were confluence and dilated. From ECG we found atrial flutter with variable conduction. This patient was transferred to HCU. This patient treated with digoxin, furosemide, milrinon, ceftriaxone, miniaspi, sildenafil, electrophysiology, and 3D ablation.  Conclusion: Pulmonary hypertension can occur in cases of congenital heart defects, such as ASD. The operative management of ASD is closure of the ASD, but in some unique groups, this can lead to pulmonary hypertensive crisis after its closure.

Chiari Network: Cause of an Unusual Difficulty during Atrial Septal Defect Device Closure

We report an unusual difficulty in unscrewing and releasing the atrial septal defect device during device closure because of the entrapment of the delivery cable in the prominent Chiari network. We suggest careful pre- and intra-procedure transesophageal guidance in recognizing and managing this rare challenge.

Off-label use of muscular VSD device for closure of a rare congenital portosystemic shunt

BackgroundCongenital portosystemic shunt (CPSS) is a vascular malformation in which portal blood drains toward the systemic circulation, leading to pulmonary hypertension.Case presentationA 10-year-old patient was brought for evaluation because of dyspnea on exertion. Echocardiography revealed a pulmonary hypertension of 75 mmHg, and multi-slice CT angiography revealed the presence of a CPSS. Closure was finally implemented using a muscular ventricular septal defect device. Follow-up of the patient revealed a gradual decline in pulmonary hypertension.ConclusionsCPSS is an overlooked cause of reversible pulmonary hypertension (PH). Closure of such lesions and reversal pulmonary hypertension are possible via catheterization. The preferred device type depends largely on the intervening team. Plugs are the first choice for interventional radiologists, while ventricular and atrial septal occluder devices and duct occluders are preferred by pediatric cardiologists.

Adverse events associated with anastomotic coupling devices in microvascular reconstruction

ObjectiveIn light of the recent US Food and Drug Administration (FDA) Class 2 safety recall notice for anastomotic coupling devices, it is important to understand related adverse events. The aim of this study was to characterize adverse events in anastomotic coupling devices for microvascular reconstruction. MethodsA retrospective cross-sectional analysis using the 2011 to 2021 US FDA Manufacturer and User Facility Device Experience (MAUDE) database. All reports of adverse events involving anastomotic coupling devices were retrieved from the MAUDE database. Descriptive statistics were used to analyze categorized events. ResultsThere were a total of 293 documented adverse events related to anastomotic coupling devices. These adverse events resulted in 91 (31.1 %) patient injuries and 239 (81.6 %) device malfunctions. The most frequent patient problems were thrombosis/hematoma (n = 38; 41.8 %), unspecified injury (n = 31; 34.1 %), and failure to anastomose (n = 13; 14.3 %). Free flap necrosis was reported in 42 % of thrombosis/hematoma cases (n = 16). The most common malfunctions were devices operating differently than expected (n = 74; 31.0 %), connection problems (n = 41; 17.2 %), and twisted/bent material (n = 19; 7.9 %). There was no significant trend in the number of adverse events over the study period (p > 0.05). ConclusionsAdverse events from anastomotic coupling devices represent an important and modifiable factor in free tissue failure. Adverse events are predominately related to devices operating differently than expected and may result in vascular compromise of the free flap. Reconstructive surgeons should be cognizant of defective anastomotic coupling devices and be prepared to utilize traditional hand-sewn anastomosis.

Original Article--Clinical and Procedural Characteristics of Successful Transcatheter Device Closure of Ostium Secundum Atrial Septal Defect in Symptomatic Children Weighing

This retrospective study sought to determine the feasibility of transcatheter atrial septal defect device closure in patients less than 15 kg, as well as to assess complication rates and the reasons for unsuccessful device closure. In general, the risks associated with transcatheter atrial septal defect device closure are believed and reported to be relatively low, but the evidence stems from trials involving adults and older children. Current guidelines do not recommend atrial defect closure in device closure in children <15 kg, due to limited data available for feasibility and safety of device closure in this group of patients. Retrospective review of all patients who underwent elective transcatheter closure of ostium secundum atrial septal defect between September 2013 to February 2022. We excluded all children above 15 kg, as well as those with complex congenital heart defects. Major and minor complications were predefined and indications for referral were evaluated. We identified 81 patients meeting criteria with a median procedural age of 3 years (1 year-8 years), and median weight of 12 kg (4-15 kg). Successful device closure was achieved in 95.1% (77/81) and in 4.9% (4/81), the procedure was aborted. There was 1 major (1.2%) and 1 minor (1.2%) complication, total complication rate (2.4%). 100% of the referrals had right heart enlargement and exertional dyspnoea, 18.5% had recurrent lower respiratory tract infection and 9.9% had failure to thrive. Rate of resolution of residual shunt was 95.1%. at post-procedure day 1 and 98.8% at post-procedure 3 and 6 months respectively. Percutaneous atrial septal defect closure can be done effectively and safely in symptomatic children weighing less than 15 kg in experienced centres. However, deferral for closure until the historically established timeline of around 4-5 years of age should be strongly considered in asymptomatic children.

Percutaneous Transcatheter Therapy in a Case of Lutembacher’s Syndrome

Lutembacher’s syndrome is a rare condition and is most often treated surgically. Due to the advances in percutaneous procedures, this form of management is desired which has the advantage of decreased morbidity and is aesthetically superior. In this case report of percutaneous treatment for a Lutembacher’s patient the percutaneous transvenous mitral commissurotomy and atrial septal defect device closure was done with minimal technical difficulties and with excellent post-procedure results.

Dynamics of Elliptical Magnetic Skyrmion in Defective Racetrack

Recently, it has been reported that the skyrmion Hall effect can be suppressed in an elliptical skyrmion-based device. Given that defects are unavoidable in materials, it is necessary and important to investigate the dynamics of an elliptical skyrmion in a defective racetrack device. In this work, the current-driven dynamics of an elliptical skyrmion in a defective racetrack device are systematically studied using micromagnetic simulations. The system energy analysis reveals that the magnetic parameters of the circular defect play critical roles in determining the type (repulsive or attractive) and the magnitude of the force on the elliptical skyrmion. The simulated trajectories show that the primary motion modes of the elliptical skyrmion in the defective racetrack can be divided into four types, which are dependent on the values of the Dzyaloshinskii–Moriya interaction (DMI) constant Dd, the perpendicular magnetic anisotropy constant Kd, the magnitude of the driving current density J, and the size d of the defect. Further investigation of the motion-mode phases of the skyrmion reveals the synthetic effects of Dd, Kd, J, and d. Finally, the minimum depinning current density J, which linearly depends on the parameters of Dd and Kd, is obtained for a skyrmion completely pinned in the defect. Our findings give insights into the dynamics of an elliptical skyrmion in the presence of a defect with different magnetic parameters in a racetrack device and may be useful for performance enhancement of skyrmion-based racetrack memory devices.

Efficient Bayesian inference for a defect rate based on completely censored data

This paper discusses the challenging issues that reliability practitioners face in conducting destructive tests that lead to completely censored lifetimes, especially in estimating the defect rate of products. Manufacturers need to measure the defect rate for quality control purposes, but obtaining enough defective devices for accurate estimation is not easy when the defect rate is relatively low. To address the issues, a Bayesian approach for estimating the defect rate is proposed in this paper. The proposed method is devised to make up for the heavy computational burdens of the Metropolis-Hastings algorithm. To quantify the uncertainty in the Bayesian estimation, a nonparametric bootstrap technique is employed to construct a credible interval for the defect rate. The performance of the proposed method is evaluated through a variety of Monte Carlo simulation studies. The efficiency of the proposed Bayesian estimation procedure is validated using a real-world dataset of return-springs in DC motor systems under an accelerated destructive degradation test.