• Journal of Chest Surgery
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• 제46권4호
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• pp.289-292
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• 2013

Through the use of a dual chamber (DDD) pacemaker, we achieved a cardiac resynchronization effect in a 51-year-old female patient who was transferred to our hospital from another hospital for an operation for three-vessel coronary artery disease. Her electrocardiogram showed a left bundle branch block (LBBB) and a prolonged QRS interval of 166 milliseconds. Severe left ventricle (LV) dysfunction was diagnosed via echocardiography. Coronary artery bypass grafting (CABG) was then performed. In order to accelerate left atrial activation and reduce the conduction defect, DDD pacing using right atrial and left and right ventricular pacing wires was initiated postoperatively. The cardiac output was measured immediately, and one and twelve hours after arrival in the intensive care unit. The cardiac output changed from 2.8, 2.4, and 3.6 L/min without pacing to 3.5, 3.4, and 3.5 L/min on initiation of pacing. The biventricular synchronization using DDD pacing was turned off 18 hours after surgery. She was transferred to a general ward with a cardiac output of 3.9 L/min. In patients with coronary artery disease, severe LV dysfunction, and LBBB, cardiac resynchronization therapy can be achieved through DDD pacing after CABG.

• Biomolecules & Therapeutics
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• 제6권2호
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• pp.199-203
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• 1998

Acute hemodynamic effects of CJ-18513, a non-peptide angiotensin IIreceptor antagonist, were examined in mongrel dogs treated with high frequency ventricular pacing for one week. Rapid ventricular pacing reduced mean blood pressure (mBP), Lvdp/dt and cardiac output (CO), and increased the left ventricular end-diastolic pressure (LVEDP) and pulmonary capillary wedge pressure (PCWP). Continuous infusion of CJ-10513 at doses of 10 and 20$\mu$g/kg/min, respectively, for 30 minutes reduced mBP, LVEDP and myocardial oxygen consumption rate (MVO,) and shifted the cardiac function curve (CO-LVEDP ourve) to the left in this dog model. In conclusion, CJ-10513 decreased the preload and afterload and increased the cardiac function in dogs with pacing-induced heart failure.

• Korean Circulation Journal
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• 제53권7호
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• pp.483-496
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• 2023

Background and Objectives: Atrial fibrillation (AF) is associated with decreased cardiac resynchronization therapy (CRT) benefits compared to sinus rhythm (SR). Effective biventricular (BiV) pacing is a determinant of CRT success, but AF can interfere with adequate BiV pacing and affect clinical outcomes. We investigated the effect of device-detected AF on clinical outcomes and optimal BiV pacing in patients with heart failure (HF) treated with CRT. Methods: We retrospectively analyzed 174 patients who underwent CRT implantation between 2012 and 2019 at a tertiary center. The optimal BiV pacing percentage was defined as ≥98%. Device-detected AF was defined as an atrial high-rate episode ≥180 beats per minute lasting more than 6 minutes during the follow-up period. We stratified the patients without preexisting AF at pre-implantation into device-detected AF and no-AF groups. Results: A total of 120 patients did not show preexisting AF at pre-implantation, and 54 had AF. Among these 120 patients, 19 (15.8%) showed device-detected AF during a median follow-up of 25.1 months. The proportion of optimal BiV pacing was significantly lower in the device-detected AF group than in the no-AF group (42.1% vs. 75.2%, p=0.009). The devicedetected AF group had a higher incidence of HF hospitalization, cardiovascular death, and all-cause death than the no-AF group. The device-detected AF and previous AF groups showed no significant differences regarding the percentage of BiV pacing and clinical outcomes. Conclusions: For HF patients implanted with CRT, device-detected AF was associated with lower optimal BiV pacing and worse clinical outcomes than no-AF.

• Journal of Chest Surgery
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• 제31권4호
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• pp.398-401
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• 1998

단극유도의 심박조율기를 가진 56세 여자환자에서 관상동맥 우회로술과 승모판 치환술을 시행하였다. 이러한 단극유도 심박조율기는 심근 외의 전자기의 간섭에 대한 감수성이 높으므로 개심술시 전기소작기의 전기파에 의해 심박조율기의 조율기능이 억제될 수 있으며, 수술후 제세동기 사용할 때 영구 심박조율기에 전기 충격이 갈 수 있다. 따라서 대동맥 차단 감자를 해제한 후 심실세동없이 정상 심박동을 유도해야 한다. 본 환자에서 임시형 심방실 유도를 거치하고 임시형 심박조율기로 조율하여 심장리듬과 심기능을 유지시키면서 전기소작기를 사용할 수 있었으며, 대동맥 차단 중 전행성 및 역행성으로 혈성심정지액을 투여하고 대동맥 차단감자를 해제하기 직전에는 온혈심정지액과 온혈의 순차적인 역행성 주입으로 자연적인 심장리듬을 회복시킴으로써 제세동기 사용을 배제할 수 있었다.

• Journal of Chest Surgery
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• 제24권11호
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• pp.1081-1089
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• 1991

Atrial fibrillation is characterized by beat to beat irregularity of shape, size, conduction time and polarity. The mechanism of atrial fibrillation can be explained by so called "Multiple wavelet theory". The adverse effect of atrial fibrillation is the decrease of cardiac output by absence of atrial kick[10 ~ 15%] and the possibility of thrombosis in the left atrium which is dangerous to develop the thromboembolism is increased. The present study was designed to assess the effect of overdrive pacing on the suppression of recurring of atrial fibrillation after open heart surgery and the results were summarized as follows: 1. There were no significant differences of factors between converting patients and non-converting patients to normal sinus rhythm by electric cardioversion after open heart surgery. 2. Among converting patients to normal sinus rhythm, there were no significant differences of factors between study group and control group. 3. Cardiothoracic Ratio on the preoperative chest film was significantly larger in the patients of recurring atrial fibrillation within 72hrs than in the patients of maintaining normal sinus rhythm. [61.7$\pm$ 1.4% vs 67.7$\pm$2.4%, p=0.03] 4. There was a significant difference of suppressive effects between overdrive pacing group and control group among recurred cases until 24, 48, and 72hours [Fisher`s exact test ; p=0.037, p=0.076, p=0.53, respectively] 5. There was a difference of the delay of recurring of atrial fibrillation between study group and control group among recurred cases within 72 hours.[53.4$\pm$6.9hr vs. 19.3$\pm$3.8 hr, p<0.01] We think that the overdrive pacing may suppress the natural pacemaker and the converted normal sinus rhythm is maintained longer than control group during critical immediate postoperative period.ve period.

• 감성과학
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• 제12권1호
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• pp.33-44
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• 2009

본 연구는 방송 영상물을 시청할 때 나타나는 감성적으로 긍정적 내용과 부정적 내용의 차별적 영향에 대해 탐구하는 한편, 형식적 특성 중 하나인 편집속도와의 상호작용을 고찰하였다. 연구는 실험으로 진행하였으며, 피험자가 메시지를 보는 동안 심박률과 피부 전도성 측정을 통해 주의와 각성 수준을 관찰하였다. 전체 메시지를 다 본 후 피험자들은 자유회상기억에 관한 문항을 작성하였다. 연구의 결과는 각성 수준을 통제하였을 때, 수용자들은 긍정적 내용보다 부정적 내용에 더 주의를 기울였지만 기억하는 정도는 반대로 긍정적 내용이 우세하였다. 한편 편집속도를 높이는 것이 감성적인 내용에 대한 반응에서 각성, 주의, 그리고 기억 수준을 높이는 것으로 나타났다. 하지만 그 효과는 긍정적, 부정적 내용에 따라 차별적이었다. 편집속도를 높이는 것이 부정적인 내용에는 별로 효력이 없거나 오히려 악영향을 미칠 수 있다는 결과가 도출되었다. 본 연구는 감성 연구에서 감성 유인가의 비대칭성에 대한 이해를 심화하고, 또한 감성 유인가적 내용과 형식적인 특성과의 상호작용이라는 새로운 연구 영역을 제시한다.

• 대한의용생체공학회:의공학회지
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• 제36권5호
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• pp.198-203
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• 2015

The purpose of the study is to examine the effects of pacemaker location on cardiac pumping efficacy theoretically. We used a three-dimensional finite element cardiac electromechanical model of canine ventricles with models of the circulatory system. Electrical activation time for normal sinus rhythm and artificial pacing in apex, left ventricular free wall, and right ventricular free wall were obtained from electrophysiological model. We applied the electrical activation time maps to the mechanical contraction model and obtained cardiac mechanical responses such as myocardial contractile ATP consumption, stroke work, stroke volume, ejection fraction, and etc. Among three artificial pacing methods, left ventricle pacing showed best performance in ventricular pumping efficacy.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제24권2호
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• pp.83-109
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• 2021

In the early stage of lesson enactment process, teachers use textbooks and other resources to select tasks and activities. It follows that discrepancies between textbooks and research-recommended pathways for learning may lead to concerns or issues with pacing in the classroom. To explore this idea further, this study examined the alignment between three popular standards-aligned textbooks series and volume learning trajectories. The results indicated that the standards-based textbooks examined may lack attention to important topics in the pacing of volume instruction, and suggest the need to inform both pre-service and in-service teachers about the gap between textbook lessons and volume learning trajectories so that they will be able to reflect students' thinking in volume learning trajectory to their lessons.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(II)
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• pp.962-964
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• 1987

In this paper a virtual route pacing control mechanism is introduced to the flow control of M-hop virtual route in the packet data network. The results described in this paper show us a comparison of the relationship between the throughput and the time-delay with the variation of the parameter, the normalized applied load. for the fixed window size.

• Journal of Chest Surgery
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• 제43권6호
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• pp.769-773
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• 2010

전신저혈압은 흉부대동맥질환의 스텐트 그라프트 치료에 전통적으로 많이 이용되어 왔으나, 혈관확장제를 이용한 혈압강하는 심박출량을 증가시킬 수 있으며 이로 인해 스텐트 그라프트의 전개 시 바람자루효과가 발생할 수 있다. 빠른 심실유도는 자동제어방식으로 일시적인 심박출량의 정지를 유도하여 심정지 지속시간이 제어 가능하고, 스텐트 그라프트 전개 시 대동맥 손상을 최소한으로 줄일 수 있다는 장점이 있다. 본원에서는 흉부대동맥궁 하방에 발생한 주머니동백자루 환자에게 빠른 심실유도하에 Valiant Captivia 스텐트 그라프트를 이용하여 효과적으로 혈관내 스텐트 그라프트 시술을 하였기에 문헌 고찰과 함께 보고하는 바이다.