• Journal of Chest Surgery
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• v.28 no.7
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• pp.666-670
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• 1995

A total of and consecutive 87 patients underwent concomitant double mitral and aortic valve replacement with the St. Jude Medical prosthesis between January 1985 and December 1993. They were 44 males and 43 females with the ages ranging from 18 to 59 years[mean$\pm$SD: 40.9$\pm$9.5 years . Fifteen patients[17.2% had a history of previous cardiac valve replacement. There were 2 early deaths[2.3% , and 85 early survivors were followed up for a total of 352.6 patient-years[mean$\pm$SD: 4.1 $\pm$2.6 years . All were anticoagulated with coumadin keeping the target international normalized ratio within the range of 1.5 and 2.5. There was a single late death[late mortality of 0.284%/patient-year . Thromboembolism was the most frequent complication[1.985%/patient-year , and bleeding related to anticoagulation was experienced in one patient [0.284%/patient-year . The incidences of prosthetic valve endocarditis and of paravalvular leak were also low[0.284%/patient-year, respectively . The survival including operative mortality was 96.1%$\pm$2.2% at 10 years. The actuarial probabilities of freedom from thromboembolism and from all events were 77.9%$\pm$11.1% and 72.4%$\pm$10.7%, respectively, at 10 years. There was no structural failure of the prosthesis. Results from a series of clinical studies suggest strongly that the use of lower intensity of anticoagulation therapy lowers the thromboembolic as well as bleeding rates in patients with the ST. Jude Medical prosthesis.

• International Journal of Arrhythmia
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• v.19 no.3
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• pp.235-284
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• 2018

In this part the writing group will cover strategies, techniques, and endpoints of atrial fibrillation (AF) ablation. Prior to all, electrical isolation of the pulmonary veins is recommended during all AF ablation procedures. In addition, techniques to be used for ablation of persistent and long-standing persistent AF, adjunctive ablation strategies, nonablative strategies to improve outcomes of AF ablation, and endpoints for ablation of paroxysmal, persistent, and long-standing persistent AF will be reviewed. Currently many technologies and tools are employed for AF ablation procedures. Radiofrequency energy, cryoablation, and other energy sources and tools are in various stages of development and/or clinical investigation. Finally, anticoagulation strategies pre-, during, and postcatheter ablation of AF and technical aspects of ablation to maximize safety are discussed in this section.

• Journal of Yeungnam Medical Science
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• v.40 no.3
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• pp.276-282
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• 2023

Background: Bleeding and thrombosis are major complications associated with high mortality in extracorporeal membrane oxygenation (ECMO) management. Anticoagulant therapy should be adequate to reduce thrombosis. However, related studies are limited. Methods: We retrospectively reviewed all patients supported with ECMO at a single institution between January 2014 and July 2022 and included those on all types of ECMO using the Permanent Life Support System. Patients were classified into two groups according to their measured mean activated partial thromboplastin time (aPTT) during ECMO management: a high-anticoagulation (AC) group (aPTT, ≥55 seconds; n=52) and a low-AC group (aPTT, <55 seconds; n=79). The primary outcome was thrombotic or bleeding events during ECMO. Results: We identified 10 patients with bleeding; significantly more of these patients were in the high-AC group (n=8) than in the low-AC group (15.4% vs. 2.5%, p=0.01). However, thrombus events and oxygenator change-free times were not significantly different between the two groups. Four patients in the high-AC group died of bleeding complications (brain hemorrhage, two; hemopericardium, one; and gastrointestinal bleeding, one). One patient in the low-AC group developed a thrombus and died of ECMO dysfunction due to circuit thrombosis. Conclusion: Heparin did not significantly improve thrombotic outcomes. However, maintaining an aPTT of ≥55 seconds was a significant risk factor for bleeding events, especially those associated with mortality.

• Journal of Chest Surgery
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• v.42 no.2
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• pp.193-200
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• 2009

Background: The long-term administration of oral anticoagulant to the patients with a mechanical heart valve prosthesis is mandatory. However, the appropriate intensity of oral anticoagulant therapy to prevent thromboembolic or hemorrhagic complications is still controversial. We tried to apply low intensity anticoagulant therapy for which the International Normalized Ratios ranged between 1.5 and 2.5, and we analyzed the anticoagulation-related long term outcomes. Material and Method: From January 1992 to December 2002, 144 patients who underwent a single cardiac valve replacement were included in the study, and their ages ranged from 15 to 72 years (mean age: $47.4{\pm}15.1$): there were 49 aortic valve replacements (AVR) and 95 mitral valve replacements (AVR). The patients were followed up monthly or bi-monthly at the outpatient clinic with clinical examinations and measuring the prothrombin time to adjust the International Normalized Ratios (INRs) within the low-intensity target range between 1.5 and 2.5. Result: The follow-up period was 835.3 patient-years (mean: $5.9{\pm}3.5$) and the INRs of 7,706 measurements were available for evaluation. The mean INRs of the aortic and the mitral valve replacement groups were significantly different (p<0.01). All the patients' INRs were within the target range in 61.9% of the measurements. The mean INRs $(2.16{\pm}0.23)$ of the patients with atrial fibrillation, which was found in 30.3% of the patients, were definitely higher than those $(2.03{\pm}0.27)$ measured in the patients with regular rhythm (p<0.01). Thromboembolic episodes occurred in 9 patients with an incidence of 1.08%/patient-year. Major bleeding occurred in 2 patients (MVR) with an incidence of 0.24%/patient-year. The patients who displayed better compliance showed a lower incidence of complications (p=0.000). Conclusion: The anticoagulation therapy with a low-intensity target range after MVR or AVR seems to be effective and feasible, and increasing the patients’ compliance should be done for achieving more effective anticoagulation therapy.

• Microbiology and Biotechnology Letters
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• v.41 no.2
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• pp.228-235
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• 2013

Radish (Raphanus sativus) is a common cruciferous vegetable, and its aerial parts, called Mu-chung in Korean, have plentiful nutritional components such as vitamins, minerals and dietary fibers. Mu-chung has been used as a kimchi, a traditional Korean fermented dish, and dried Mu-chung is an important component of soups commonly consumed during winter in Korea. Since the advent of the mass production of radish in Korea, with the segregation of farm areas and towns and changing diets, Mu-chung has mostly been discarded instead of utilized. In addition, studies concerning the efficient utilization and useful bioactivities of Mu-chung are still lacking worldwide. In this study, we prepared the ethanol extract of Mu-chung and its subsequent solvent fractions. Antimicrobial, antioxidation, and anticoagulation activities were then evaluated in the hopes of developing a functional biomaterial from Korean radishes' aerial parts. The ethanol extraction yield for hot-air dried Mu-chung was 5.6%, and the fraction yields of n-hexane (H), ethylacetate (EA), butanol (B) and water residue were 25.3, 3.6, 19.4, and 51.7%, respectively. Analysis of total polyphenol and total flavonoid contents showed that the EA fraction had the highest content (97.57 and 152.91 mg/g) amongst the fractions. In antimicrobial activity assays, the H and EA fractions were effective against gram positive bacteria (Staphylococcus aureus, Listeria monocytogenes, and Bacillus subtilis), but not effective against gram negative bacteria (Escherichia coli and Pseudomonas aeruginosa). The B fraction also exhibited moderate antibacterial activity, suggesting that the extract of Mu-chung has various antibacterial components. In antioxidation activity assays, the EA fraction showed strong DPPH, ABTS and nitrite scavenging activities ($69-222{\mu}g/ml$ of $IC_{50}$), including reducing power. In anticoagulation activity assays, the EA fraction demonstrated strong inhibition activity against human thrombin and prothrombin. Prominent anticoagulation activity was found in aPTT assays; the aPTT of the EA fraction was extended 15-fold compared than that of the solvent control. Our results suggest that Mu-chung is an attractive nutritional food material possessing useful bioactivities, and the EA fraction of Mu-chung could be developed as a functional food ingredient.

• Journal of Chest Surgery
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• v.43 no.3
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• pp.266-272
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• 2010

Background: Deep vein thrombosis (DVT) is a serious disease that causes life-threatening pulmonary embolism and chronic venous insufficiency. Anticoagulation is the standard therapy for DVT. However, the results of standard anticoagulation for treating DVT have been disappointing, so endovascular treatment is commonly performed nowadays. The aim of this study was to evaluate the efficacy of an endovascular procedure for treating patients with DVT. Material and Method: We retrospectively evaluated the clinical data of 29 DVT patients who underwent an endovascular procedure between December 2006 and July 2008. We compared the results of the 29 patients with the results of another 45 patients who were treated with only aspirin and heparin. Result: The patient’s mean age was 55.4 years in the intervention group and 53.7 years in the control group. DVT occurred more frequently in the females. Catheter-directed thrombolysis was performed in 22 patients (75.8%). Aspiration thrombectomy was performed in 18 patients (62%) and a endovascular stent was placed in 25 patients (86.2%). Fifteen patients (51.7%) underwent percutaneous insertion of a retrievable IVC filter for the prevention of pulmonary embolism. In the control group, thirty nine patients (86.7%) were treated with low-molecular heparin, and seven patients (15.6%) who were contraindicated for warfarin were treated with aspirin. No bleeding complications occurred during thrombolysis or anticoagulation. We analyzed the statistical data according to recurrence of DVT and the incidence of post-thrombotic syndrome (PTS) during the follow-up period. The intervention group had a significantly lower incidence of PTS (p-value=0.008), but they had the same result as the control group for the recurrence of DVT. In addition, death from the DVT did not occur in the intervention group. Thus, we obtained better clinical outcomes in the intervention group as compared to those in the anticoagulation only group. Conclusion: Endovascular procedures are effective alternative modalities, as compared to systemic anticoagulation, for the treatment of DVT. But more studies are needed to determine the specific indications and to validate the long-term efficacy of endovascular procedures for the treatment of DVT.

• Journal of Chest Surgery
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• v.51 no.2
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• pp.100-108
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• 2018

Background: The question of which type of prosthetic aortic valve leads to the best outcomes in patients in their 60s remains controversial. We examined the hemodynamic and clinical outcomes of aortic valve replacement in sexagenarians according to the type of prosthesis. Methods: We retrospectively reviewed 270 patients in their 60s who underwent first-time aortic valve replacement from 1995 to 2011. Early and late mortality, major adverse valve-related events, anticoagulation-related events, and hemodynamic outcomes were assessed. The mean follow-up duration was $58.7{\pm}44.0$ months. Results: Of the 270 patients, 93 had a mechanical prosthesis (mechanical group), and 177 had a bioprosthesis (tissue group). The tissue group had a higher mean age and prevalence of preoperative stroke than the mechanical group. The groups had no differences in the aortic valve mean pressure gradient (AVMPG) or the left ventricular mass index (LVMI) at 5 years after surgery. In a sub-analysis limited to prostheses in the supra-annular position, the AVMPG was higher in the tissue group, but the LVMI was still not significantly different. There was no early mortality. The 10-year survival rate was 83% in the mechanical group and 90% in the tissue group. The type of aortic prosthesis did not influence overall mortality, cardiac mortality, or major adverse valve-related events. Anticoagulation-related events were more common in the mechanical group than in the tissue group (p=0.034; hazard ratio, 4.100; 95% confidence interval, 1.111-15.132). Conclusion: The type of aortic prosthesis was not associated with hemodynamic or clinical outcomes, except for anticoagulation-related events.

• Journal of Life Science
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• v.26 no.3
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• pp.289-295
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• 2016

Sorbus commixta, a flowering plant in the Rosaceae family, is native to Japan and Ulleung Island, Korea. This plant is also called maga-mok or mai-mok in Korea because the bud of the stem has a similar shape to the teeth of a horse. In this study, hot water extracts from different parts of S. commixta, such as leaf, stem, and immature and mature fruits, were prepared, and their antithrombosis and antioxidant activities were evaluated. The extraction yield and pH of stem extracts were 3.99% and 5.5, respectively. The stem extracts contained 89.2 mg/g of total polyphenols and 28.3 mg/g of total flavonoids. The hot water extracts prepared from the leaf, stem, immature, and mature fruit of S. commixta exhibited no hemolytic activity against human red blood cells, up to a concentration of 0.5 mg/ml. In an anticoagulation assay, the stem extracts showed strong extension in thrombin, prothrombin, and activated partial thromboplastin times, whereas the other extracts had no anticoagulation activity. In a platelet aggregation inhibitory activity assay, all the extracts tested had no inhibitory activity against human platelets. With regard to antioxidation activity, the stem extracts showed stronger radical scavenging activity and reducing power activity than the other extracts. The calculated RC₅₀s, the concentration required for 50% radical scavenging activity, for DPPH anions, ABTS cations, and nitrite of the crude stem extracts were 119.7, 53.3, and 117.5 μg/ml, respectively, whereas they were 13.7, 5.2, and 14.9 μg/ml for DPPH anions, ABTS cations, and nitrite, respectively, for vitamin C. The results suggest that the stem extracts of S. commixta have strong potential for use as a novel resource for antithrombosis agents.

• Journal of Life Science
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• v.24 no.5
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• pp.515-521
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• 2014

The oriental traditional medicine, Aruncus dioicus var kamtschaticus (ADK) is used for hemostasis (blood stopping) and the promotion of blood circulation. Recently, the demands of the aerial part of ADK as edible mountain herbs are rapidly increased due to its unique fragrance and bioactivity. In this study, to evaluate the anti-thrombosis activity of ADK, ethanol extract and organic solvent fractions were prepared from aerial parts of ADK, and their anticoagulation and anti-platelet aggregation activities were determined. In an anticoagulation activity assay, the ethanol extract of ADK increased the thrombin time, prothrombin time, and activated partial thromboplastin time (aPTT) 1.4-2.3 times at a concentration of 5 mg/ml. Among the fractions, the ethylacetate fraction showed strong inhibitory effects against blood clotting factors, as shown in an extension of the aPTT. In contrast, the butanol fraction strongly promoted blood clotting. In an anti-platelet aggregation assay, the activity of the ethanol extract was comparable to that of aspirin, a commercial anti-platelet aggregation agent, and the butanol fraction showed 2-fold higher aggregation inhibitory activity than aspirin. The aforementioned ethanol extract and active fractions have ignorable hemolytic activity against human red blood cells up to a concentration of 0.5 mg/ml. Considering the high content of total polyphenol, total flavonoid, and total sugar of the ethylacetate and butanol fractions, the purified active substances have potential as safe and novel anti-thrombosis agents. This report provides the first evidence of anti-thrombosis activity of ADK.

• Journal of The Korean Society of Clinical Toxicology
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• v.7 no.2
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• pp.164-171
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• 2009

Purpose: The number of patients who take warfarin is growing and so is the number of complications. Hemorrhage is the major complication, but the clinical characteristics and outcomes have not been determined for Korean patients. Therefore, we tried to evaluate the characteristics of the patients with hemorrhagic complications after taking warfarin as anticoagulation therapy. Methods: We retrospectively reviewed the medical records of the patients who visited the emergency room with bleeding complications after taking warfarin anticoagulation at the out-patient clinic for 1 year from 1 st January 2008. We compared between two groups (the major hemorrhage group vs. the minor hemorrhage group) according to the clinical criteria, the unstable vital signs that required blood transfusion, transfusion more than 2 units of blood, the need for further laboratory follow-up, the need for interventional treatment and the development of critical complications or death due to bleeding. Results: There were 150 patients who met the criteria and had acute hemorrhagic complications (the major group: 90 patients and the minor group: 60 patients). In the major hemorrhage group, the frequent sites of bleeding were the gastro-intestinal system (40 patients), lung (14 patients) and intracranium (7 patients). At the emergency room, the major group showed a higher initial INR of the activated prothrombin time than did the minor group (p=0.02). The bleeding sites of the fatal cases were the gastro-intestinal system (3 patients), lung (3 patients) and intracranium (3 patients), but the percentage of fatality was the highest for intracranium bleeding. Conclusion: In the major hemorrhage group, gastrointestinal bleeding was the most frequent complication and fatality was the highest for intracranium bleeding. An initially higher INR showed a greater risk of major bleeding, but not more fatalities.