• Journal of Chest Surgery
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• v.51 no.1
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• pp.1-7
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• 2018

Background: Sutureless aortic valve replacement (SU-AVR) has been developed as an alternative surgical treatment for patients with symptomatic severe aortic stenosis (AS). The aim of this study was to evaluate the clinical outcomes of SU-AVR through an assessment of hemodynamic performance and safety. Methods: From December 2014 to June 2016, a total of 12 consecutive patients with severe AS underwent SU-AVR. The endpoints were overall survival and valve-related complications (paravalvular leakage, valve thrombosis, migration, endocarditis, and permanent pacemaker implantation). The mean follow-up duration was $18.1{\pm}8.6months$. Results: The mean age of the patients was $77.1{\pm}5.8years$ and their mean Society of Thoracic Surgeons score was $9.2{\pm}17.7$. The mean cardiopulmonary bypass and aortic cross-clamp times were $94.5{\pm}37.3$ minutes and $54.9{\pm}12.5minutes$, respectively. Follow-up echocardiography showed good prosthesis function with low transvalvular pressure gradients (mean, $13.9{\pm}8.6mm\;Hg$ and peak, $27.2{\pm}15.0mm\;Hg$) at a mean of $9.9{\pm}4.2months$. No cases of primary paravalvular leakage, valve thrombosis, migration, or endocarditis were reported. A new permanent pacemaker was implanted in 1 patient (8.3%). The 1-year overall survival rate was $83.3%{\pm}10.8%$. Conclusion: Our initial experience with SU-AVR demonstrated excellent early clinical outcomes with good hemodynamic results. However, there was a high incidence of permanent pacemaker implantation compared to the rate for conventional AVR, which is a problem that should be solved.

• Journal of Dental Anesthesia and Pain Medicine
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• v.20 no.4
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• pp.233-240
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• 2020

Background: Palatal injection of local anesthetics is the most painful injection. To obviate the need for palatal injections, local anesthetic agents with diffusibility are being investigated. Hence the present study was designed to analyze the anesthetic efficacy of 2% lidocaine hydrochloride (HCl) with 1:100,000 adrenaline and 4% articaine hydrochloride (HCl) with 1:100,000 adrenaline using single buccal infiltration for the extraction of maxillary premolars. Methods: A prospective, double-blind, crossover, randomized clinical study was performed on 60 consecutive systemically healthy patients with an age range of 15-30 years, requiring extraction of asymptomatic bilateral maxillary premolars for orthodontic purposes. They received 1ml buccal infiltration of 4% articaine HCl with 1:100,000 adrenaline on one side and 2% lidocaine HCl with 1:100,000 adrenaline on the other side. The extraction procedure on either side was scheduled 14 days apart. Parameters assessed were the time of onset of anesthesia, intraoperative discomfort, hemodynamic parameters, and the duration of analgesia. Analysis of the data was done using the Mann-Whitney test, the Wilcoxon test, the Kruskal-Wallis ANOVA test, and the chi-square test. Statistical significance was established at P < 0.05. Results: Articaine showed a faster time of onset and longer duration of analgesia than lidocaine. However, the difference in the intraoperative discomfort and hemodynamic parameters was statistically insignificant. Conclusion: Within the limitations of the study, it can be concluded that the extraction of maxillary premolars can be performed with a single buccal infiltration of 2% lidocaine HCl with 1:100,000 adrenaline, which is one of the most commonly used local anesthetic agent.

• Archives of Pharmacal Research
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• v.14 no.3
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• pp.242-248
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• 1991

Antihypertensive effect of YH 334 was examined in various experimental hypertension rat models and the systemic and regional hymohynamic profiles of the compound were investigated in conscious spontaneously hypertensive rats (SHR). The antiypertensive potensive potency of YH 334 is found to be more than 10 times stronger than that of nitrendipine in the all hypertensive models. The effective doses to lower the initial blood pressure by 20% $(ED_{20})$ of YH334 were 1.4 mg/kg in normotensive rats (NR), 0.7 mglkg in SHR. 0.1 mg/kg in DOCA salt hypertensive rats (DHR) and 0.4 mg/kg in renal hypertensive rats (RHR), and the $ED_{20}$ values of nitrendipine were 15.8 mg/kg in NR, 7.1 mg/kg in SHR, 1.7 mg/kg in DHR and 4.8 mg/kg in RHR. The primary hemodynamic effect hemodynamic profile is similar to that of nitrendipine. Both compounds seem to produce potent antihypertensive effects by lowering peripheral resistance in the skeletal muscles. In the organ bath study using isolated rabbit aorta, YH 334 was found to be a potent voltage dependent calcium channel blocker without significant inhibitory effect on the receptor operated calcium channels like the most of other dihydropyridine type calcium antagonists. Furthermore, YH334 showed acute diuretic and natriuretic effects in conscious SHR, which may render the unnecessary restriction of sodium in the diet of those patients on long term hypertension therapy. This effect would provide an additional benefit to its potent antihypertensive activity.

• Journal of Trauma and Injury
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• v.20 no.2
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• pp.106-114
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• 2007

Purpose: There is little controversy that a classic indication such as hemodynamic instability or any sign of peritoneal irritation requires an immediate laparotomy in the management of abdominal stab wounds. However, omental herniation or bowel evisceration as an indication for an immediate laparotomy is controversial. The purpose of this study was to evaluate the significance of these factors as indications for an immediate laparotomy. Methods: The medical records of 98 consecutive abdominal stab wounds patients admitted to the Emergency Center of Masan Samsung Hospital from January 2000 to December 2006 were carefully examined retrospectively. Using multivariate logistic regression analysis, thirty-nine factors, including the classic indication and intraabdominal organ evisceration, were evaluated and were found to be associated with a need for a laparotomy. Also, the classic indication was compared with a new indication consisting of components of the classic indication and intra-abdominal organ evisceration by constructing a contingency table according to the need for a laparotomy. Results: Multivariate logistic regression analysis revealed any sign of peritoneal irritation, base deficit, and age to be significant factors associated with the need for a laparotomy (p<0.05). The sensitivity, specificity, and accuracy rates of the classic indication were 98.6%, 72.0%, and 91.8%, respectively, and those of the new indication were 93.2%, 84.0%, and 90.8%, respectively. The differences in those rates between the above two indications were not significant. Conclusion: Intra-abdominal organ evisceration was not a significant factor for an immediate laparotomy. Moreover, the new indication including intra-abdominal organ evisceration was not superior to the classic indication. Therefore, in the management of abdominal stab wounds, the authors suggest that an immediate laparotomy should be performed on patients with hemodynamic instability or with any sign of peritoneal irritation.

• Journal of Chest Surgery
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• v.49 no.4
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• pp.258-263
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• 2016

Background: The advantages of using a homograft in valve replacement surgery are the excellent hemodynamic profile, low risk of thromboembolism, and low risk of prosthetic valve infection. The aim of this study was to evaluate the long-term outcomes of homograft implantation in the aortic valve position. Methods: This is a retrospective study of 33 patients (>20 years old) who underwent aortic valve replacement or root replacement with homografts between April 1995 and May 2015. Valves were collected within 24 hours from explanted hearts of heart transplant recipients (<60 years) and organ donors who were not suitable for heart transplantation. The median follow-up duration was 35.6 months (range, 0 to 168 months). Results: Aortic homografts were used in all patients. The 30-day mortality rate was 9.1%. The 1- and 5-year survival rates were $80.0%{\pm}7.3%$ and $60.8%{\pm}10.1%$, respectively. The 1-, 5-, and 10-year freedom from reoperation rates were $92.3%{\pm}5.2%$, $68.9%{\pm}10.2%$, and $50.3%{\pm}13.6%$, respectively. The 1-, 5-, and 10-year freedom from significant aortic dysfunction rates were $91.7%{\pm}8.0%$, $41.7%{\pm}14.2%$, and $25.0%{\pm}12.5%$, respectively. Conclusion: Homografts had the advantages of a good hemodynamic profile and low risk of thromboembolic events, and with good outcomes in cases of aortitis.

• Journal of computational fluids engineering
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• v.22 no.1
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• pp.15-25
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• 2017

Swirl flow is often found in proximal coronary arteries, because the aortic valves can induce swirl flows in the coronary artery due to vortex formation. In addition, the curvature and tortuosity of arterial configurations can also produce swirl flows. The present study was performed to investigate fractional flow reserve alterations in a post-stenotic distal part due to the presence of pre-stenotic swirl flow by computational fluid dynamics analysis for virtual stenotic models by quantifying fractional flow reserve(FFR). Simplified stenotic coronary models were divided into those with and without pre-stenotic swirl flow. Various degrees of virtual stenosis were grouped into three grades: mild, moderate, and severe, with degree of stenosis of 0 ~ 40%, 50 ~ 60%, and 70 ~ 90%, respectively. In this study, three-dimensional computational hemodynamic simulations were performed under hyperemic conditions in virtual stenotic coronary models by coupling with a zero-dimensional lumped parameter model. The results showed that the influence of pre-stenotic swirl inflow is dominant on FFR alteration in mild stenosis, whereas stenosis is dominant on FFR alteration in moderate/severe stenosis. The decrease in FFR caused by swirl flow is more significant in mild stenosis than moderate/severe stenosis. Biomechanical modeling is useful for clinicians to provide insight for medical intervention strategies. This hemodynamic-based parameter study could play a critical role in the development of a non-invasive imaging-based strategy-support system for percutaneous transluminal angioplasty in cases of mild/moderate stenosis.

• The Korean Journal of Nuclear Medicine
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• v.19 no.2
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• pp.43-50
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• 1985

With the improvement of hemodialysis, the course of the disease in patient with endstage renal disease has been clearly improved. Nevertheless, among several shortcomings to our present mode of renal replacement therapy, cardiovascular complications have been the leading cause of morbidity and mortality. Several factors such as anemia, arteriovenous shunting of blood, intermittent extracorporeal circulation and hypertension may be contributing. But little is known about the quantitative cardiac hemodynamic characteristics occurred during hemodialysis. The purpose of this study is to observe the sequential hemodynamic changes before, during and after the hemodialysis and to investigate reliable parameters in the detection of ventricular dysfunction. In the present study, equilibrium radionuclide cardiac angiography was performed and left and right ventricular volume indices, ejection phase indices of both ventricular, performance were measured in the 16 stable patients with chronic renal failure treated with maintenance hemodialysis sequentially i.e. before, during (early and late phase) and after the hemodialysis. The results obtained were as follows; 1) The indices of the left ventricular function were not changed during the hemodialysis but increased after the hemodialysis. 2) The indices of the right ventricular function(EF, SVI) were significantly decreased in the early phase (15, 30 minutes after starting extracorporeal circulation) but recovered after the hemodialysis. 3) The ratio of right ventricular to left ventricular ejection fraction was significantly decreased in the early phase and the lung volume indices were significantly increased at the same phase. As a conclusion, hemodialysis improves left ventricular function maybe due to increased contractility, and effects on the right ventricular function maybe due to the increased lung volume in the early phase of hemodialysis.

• Restorative Dentistry and Endodontics
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• v.27 no.5
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• pp.543-551
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• 2002

Nitric oxide (NO) is a small molecule (mol. wt. 30 Da) and oxidative free radical. It is uncharged and can therefore diffuse freely within and between cells across membrane. Such characteristics make it a biologically important messenger in physiologic processes such as neurotransmission and the control of vascular tone. NO is also highly toxic and is known to acts as a mediator of cytotoxicity during host defense. NO is synthesized by nitric oxide synthase (NOS) through L-arginine/nitric oxide pathway which is a dioxygenation process. NO synthesis involves several participants, three co-substrates, five electrons, five co-factors and two prosthetic groups. Under normal condition, low levels of NO are synthesized by type I and III NOS for a short period of time and mediates many physiologic processes. Under condition of oxidant stress, high levels of NO are synthesized by type II NOS and inhibits a variety of metabolic processes and can also cause direct damage to DNA. Such interaction result in cytostasis, energy depletion and ultimately cell death. NO has the potential to interact with a variety of intercellular targets producing diverse array of metabolic effects. It is known that NO is involved in hemodynamic regulation, neurogenic inflammation, re-innervation, management of dentin hypersensitivity on teeth. Under basal condition of pulpal blood flow, NO provides constant vasodilator tone acting against sympathetic vasoconstriction. Substance P, a well known vasodilator, was reported to be mediated partly by NO, while calcitonin-gene related peptide has provided no evidence of its relation with NO. This review describes the roles of NO in dental pulp in addition to the known general roles of it.

• Journal of Biomedical Engineering Research
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• v.23 no.2
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• pp.131-137
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• 2002

The remote monitoring system including hemodynamic information and pump status of the implanted animal could be helpful during the in vivo experiment or clinical trial for an artificial heart Implantation. In order to monitor the course of the in vivo experiment continuously and anywhere, web-based remote monitoring system was developed, which can monitor pressures(AoP, LAP, RAP, PAP) and flow information as well as the pump operating conditions. The system consists of data sending, storing viewer part. The data sending part was constructed using component object model and the viewer part was constructed using the Java applet. In addition, the dialog box was introduced to communicate earth other instantly and the alarming function was also introduced when the hemodynamic values were out of the desired ranges. The developed remote monitoring system was applied during the in vivo experiment of the BVAD (Bi-ventricular Assist Device) implantation for 1 month and showed designed work without failure.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.249-250
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• 1998

In this study, we modeled moving-actuator type Total Artificial Heart (TAH) with cardiovascular system as a form of electric circuit. The bronchial circulation, important for the imbalance between the left cardiac output and the right one, was considered and added to the model. In the model, the relations of hemodynamic variables, just as blood pressures, volumes, or flow rates of each part of body, can be expressed as simultaneous first order ordinary differential equations. To solve the equations by the numerical analysis, Runge-Kutta forth order approximation method was adopted. The simulation software (SimTAH), implemented in C++ as a window-based application program, was developed to display the hemodynamic variables and to receive control inputs from users. SimTAH was evaluated by comparison of the simulation results with the results of mock-circulation tests, in vitro.