• Korean Circulation Journal
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• v.54 no.1
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• pp.13-27
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• 2024

Background and Objectives: Comprehensive epidemiological data are lacking on the incident atrial fibrillation (AF) in patients with cardiac implantable electronic devices (CIEDs). This study aimed to examine the incidence, risk factors, and AF-related adverse outcomes of patients with CIEDs. Methods: This was an observational cohort study that analyzed patients without prevalent AF who underwent CIED implantation in 2009-2018 using a Korean nationwide claims database. The subjects were divided into three groups by CIED type and indication: pacemaker (n=21,438), implantable cardioverter defibrillator (ICD)/cardiac resynchronization therapy (CRT) with heart failure (HF) (n=3,450), and ICD for secondary prevention without HF (n=2,146). The incidence of AF, AF-associated predictors, and adverse outcomes were evaluated. Results: During follow-up, the incidence of AF was 4.3, 7.3, and 5.1 per 100 person-years in the pacemaker, ICD/CRT with HF, and ICD without HF cohorts, respectively. Across the three cohorts, older age and valvular heart disease were commonly associated with incident AF. Incident AF was consistently associated with an increased risk of ischemic stroke (3.8-11.4-fold), admission for HF (2.6-10.5-fold), hospitalization for any cause (2.4-2.7-fold), all-cause death (4.1-5.0-fold), and composite outcomes (3.4-5.7-fold). Oral anticoagulation rates were suboptimal in patients with incident AF (pacemaker, 51.3%; ICD/CRT with HF, 51.7%; and ICD without HF, 33.8%, respectively). Conclusions: A substantial proportion of patients implanted CIED developed newly diagnosed AF. Incident AF was associated with a higher risk of adverse events. The importance of awareness, early detection, and appropriate management of AF in patients with CIED should be emphasized.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.1
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• pp.92-97
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• 2009

Low power consumption is crucial for medical implantable devices. A low-power 4th-order band-pass Gm-C filter with distributed gain stage for the sensing stage of the implantable cardiac pacemaker is proposed. For the implementation of large-time constants, a floating-gate operational transconductance amplifier with current division is employed. Experimental results for the filter have shown a SFDR of 50 dB. The power consumption is below $1.8{\mu}W$, the power supply is 1.5 V, and the core area is $2.4\;mm{\times}1.3\;mm$. The filter was fabricated in a 1-poly 4-metal $0.35-{\mu}m$ CMOS process.

• Journal of electromagnetic engineering and science
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• v.10 no.4
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• pp.206-211
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• 2010

In this paper, an implantable planar inverted-F antenna (PIFA) for an artificial cardiac pacemaker is proposed. The antenna has a simple structure with a low profile and is placed on the top side of the pacemaker. The dimensions of the pacemaker system, including the antenna element, are $42{\times}43.6{\times}11$ mm. When the antenna is embedded in pig tissue, its $S_{11}$ value is -10.94 dB at 403 MHz and the -10 dB impedance bandwidth of the antenna is 6 MHz (399~406 MHz). The proposed PIFA in tissue has a peak gain of -20.19 dBi and a radiation efficiency of 1.12 % at 403 MHz. When the proposed antenna is placed in a flat phantom, its specific absorption ratio (SAR) value is 0.038 W/kg (1 g tissue). Performances of the proposed PIFA is sufficient to operate at the MICS band (402 ~ 405 MHz).

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.1
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• pp.28-36
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• 2008

This paper discusses theimplementation of the low-voltage, low-power, third-order, 1-bit switched capacitor delta-sigma modulator of the implantable cardiac pacemaker. The distributed, feed-forward structure and bulk-driven OTA were used in order to achieve an efficient operation under a supply voltage of 1V or lower. The designed modulator has a dynamic range of 49dB at 0.9V supply voltage and consumes 816nW of power. Such a significant reduction in power consumption allows diverse applications, not only in pacemakers, but also in implantable biomedical devices that operate with limited battery power. The core chip size of the modulator is $1000{\mu}m*500{\mu}m$ manufactured, with the $0.18{\mu}m$ CMOS standard process.

• Journal of Chest Surgery
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• v.16 no.2
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• pp.190-198
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• 1983

The management of cardiac arrhythmias by cardiac pacing has increased greatly since the treatment of complete heart block with an external transcutaneous pacemaker in 1952, followed by the use of myocardial wires connected to an external pulse generation, by external transvenous pacing, and then by transvenous pacing with implantable components in thoracic wall.By now, the three bases of modern cardiac pacing for bradyarrhythmias had been established [1] an implantable device [2] the transvenous approach [3] the ability of the pacemaker to sense cardiac activity and modify its own function accordingly. In transvenous implantation of a pacemaker, any one of four vessels at the root of the neck is suitable for passage of the electrode - cephalic vein, external jugular vein, internal jugular vein, costo-axillary branch of the axillary vein. The new technique of direct puncture of the subclavian vein, either percutaneously or after skin incision only has been made, is invaluable & is used routinely. We have experienced one 25 years old patient who had rheumatic mitral stenosis & minimum aortic regurgitation with sinus bradycardia associated with premature atrial tachycardia & another 54 years old female patient who was suffered from sick sinus syndrome with sinus bradycardia & sinus arrest. The 1st patient was taken open mitral commissurotomy & aortic valvuloplasty and then was taken atrlal pace-maker implantation through If subclavian puncture method in post-op 14 days, and the second patient was taken atrial pacemaker implantation through If subclavian puncture method. Their postop course was in uneventful & were discharged, without complication. Their condition have been good to now.

• Journal of Veterinary Clinics
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• v.24 no.3
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• pp.414-418
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• 2007

A 2.8-year-old intact female Beagle dog (weighing 11kg) was referred with the primary complaint of exercise intolerance with occasional syncope. Physical examination revealed irregularly irregular heart rhythm with persistent pulse deficits. The 12-lead surface ECG showed a third degree heart block. Permanent transvenous cardiac pacing with a bipolar implantable pacemaker was performed in the right ventricle. After pacemaker implantation, the dog did not show syncopal episode and is currently able to take a walk with an owner. No side effects associated with permanent pacemaker implantation has been observed to date.

• Korean Journal of Radiology
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• v.22 no.11
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• pp.1918-1928
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• 2021

Objective: With the recent development of various MRI-conditional cardiac implantable electronic devices (CIEDs), the accurate identification and characterization of CIEDs have become critical when performing MRI in patients with CIEDs. We aimed to develop and evaluate a deep learning-based algorithm (DLA) that performs the detection and characterization of parameters, including MRI safety, of CIEDs on chest radiograph (CR) in a single step and compare its performance with other related algorithms that were recently developed. Materials and Methods: We developed a DLA (X-ray CIED identification [XCID]) using 9912 CRs of 958 patients with 968 CIEDs comprising 26 model groups from 4 manufacturers obtained between 2014 and 2019 from one hospital. The performance of XCID was tested with an external dataset consisting of 2122 CRs obtained from a different hospital and compared with the performance of two other related algorithms recently reported, including PacemakerID (PID) and Pacemaker identification with neural networks (PPMnn). Results: The overall accuracies of XCID for the manufacturer classification, model group identification, and MRI safety characterization using the internal test dataset were 99.7% (992/995), 97.2% (967/995), and 98.9% (984/995), respectively. These were 95.8% (2033/2122), 85.4% (1813/2122), and 92.2% (1956/2122), respectively, with the external test dataset. In the comparative study, the accuracy for the manufacturer classification was 95.0% (152/160) for XCID and 91.3% for PPMnn (146/160), which was significantly higher than that for PID (80.0%,128/160; p < 0.001 for both). XCID demonstrated a higher accuracy (88.1%; 141/160) than PPMnn (80.0%; 128/160) in identifying model groups (p < 0.001). Conclusion: The remarkable and consistent performance of XCID suggests its applicability for detection, manufacturer and model identification, as well as MRI safety characterization of CIED on CRs. Further studies are warranted to guarantee the safe use of XCID in clinical practice.

• Archives of Plastic Surgery
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• v.44 no.1
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• pp.34-41
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• 2017

Background The current indications of cardiac implantable electronic devices (CIEDs) have expanded to include young patients with serious cardiac risk factors, but CIED placement has the disadvantage of involving unsightly scarring and bulging of the chest wall. A collaborative team of cardiologists and plastic surgeons developed a technique for the subpectoral placement of CIEDs in young female patients via a transaxillary approach. Methods From July 2012 to December 2015, subpectoral CIED placement via an axillary incision was performed in 10 young female patients, with a mean age of 25.9 years and mean body mass index of $20.1kg/m^2$. In the supine position, with the patient's shoulder abducted, an approximately 5-cm linear incision was made along one of the deepest axillary creases. The submuscular plane was identified at the lateral border of the pectoralis major, and the dissection continued over the clavipectoral fascia until the subpectoral pocket could securely receive a pulse generator. Slight upward dissection also exposed an entrance to the subclavian vein, allowing the cardiology team to gain access to the vein. One patient with dilated cardiomyopathy underwent augmentation mammoplasty and CIED insertion simultaneously. Results One case of late-onset device infection occurred. All patients were highly satisfied with the results and reported that they would recommend the procedure to others. Conclusions With superior aesthetic outcomes compared to conventional methods, the subpectoral placement of CIEDs via a transaxillary approach is an effective, single-incision method to hide operative scarring and minimize bulging of the device, and is particularly beneficial for young female or lean patients.

• Journal of Veterinary Clinics
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• v.27 no.5
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• pp.569-572
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• 2010

A 4-year-old neutered female Pekingese dog (weighing 3.6 kg) was referred with the primary complaint of exercise intolerance with occasional syncope. Physical examination revealed irregularly irregular heart rhythm with persistent pulse deficits. The 12-lead surface ECG showed a marked sinus arrest with occasional junctional escape beats, indicating a sick sinus syndrome. Permanent transvenous cardiac pacing with a rate-responsive bipolar implantable pacemaker (VVIR type) was performed in the right ventricle. After pacemaker implantation, the clinical signs were remarkably improved. No further syncopal episodes have yet been occurred after implantation.

• Journal of IKEEE
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• v.13 no.1
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• pp.77-86
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• 2009

A wavelet Electrocardiogram(ECG) detector and its analog-to-digital converter(ADC) for low-power implantable cardiac pacemakers are presented in this paper. The proposed wavelet-based ECG detector consists of a wavelet decomposer with wavelet filter banks, a QRS complex detector of hypothesis testing with wavelet-demodulated ECG signals, and a noise detector with zero-crossing points. To achieve high-detection performance with low-power consumption, the multi-scaled product algorithm and soft-threshold algorithm are efficiently exploited. To further reduce the power dissipation, a low-power ADC, which is based on a Successive Approximation Register(SAR) architecture with an on/off-time controlled comparator and passive sample and hold, is also presented. Our algorithmic and architectural level approaches are implemented and fabricated in standard $0.35{\mu}m$ CMOS technology. The testchip shows a good detection accuracy of 99.32% and very low-power consumption of $19.02{\mu}W$ with 3-V supply voltage.