Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor is essential after percutaneous coronary intervention (PCI), while many studies have focused on determining the optimal degree of platelet inhibition and optimal DAPT duration to minimize complications after PCI. Current guidelines developed by the American College of Cardiology/American Heart Association and the European Society of Cardiology summarize previous studies and provide recommendations. However, these guidelines are mainly based on Western patients, and their characteristics might differ from those of East Asian patients. Previous data suggested that East Asian patients have unique features with regard to the response to antiplatelet agents. On comparing Western and East Asian patients, it was found that East Asian patients have a lower rate of ischemic events and higher rate of bleeding events after PCI, despite a higher on-treatment platelet reactivity, which is referred to as the “East Asian paradox.” As the main purpose of DAPT is to minimize ischemic and bleeding complications after PCI, these differences should be clarified before adopting the guidelines for East Asian patients. Therefore, in this article, we will review various issues regarding DAPT in East Asian patients, with a focus on the unique characteristics of East Asian patients, previous studies regarding antiplatelet agents in East Asian patients, and a guideline from an East Asian perspective.
Asian Continental Ancestry Group ; Aspirin ; Blood Platelets ; Cardiology ; Heart ; Hemorrhage ; Humans ; Percutaneous Coronary Intervention ; Platelet Aggregation Inhibitors

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor is essential after percutaneous coronary intervention (PCI), while many studies have focused on determining the optimal degree of platelet inhibition and optimal DAPT duration to minimize complications after PCI. Current guidelines developed by the American College of Cardiology/American Heart Association and the European Society of Cardiology summarize previous studies and provide recommendations. However, these guidelines are mainly based on Western patients, and their characteristics might differ from those of East Asian patients. Previous data suggested that East Asian patients have unique features with regard to the response to antiplatelet agents. On comparing Western and East Asian patients, it was found that East Asian patients have a lower rate of ischemic events and higher rate of bleeding events after PCI, despite a higher on-treatment platelet reactivity, which is referred to as the “East Asian paradox.” As the main purpose of DAPT is to minimize ischemic and bleeding complications after PCI, these differences should be clarified before adopting the guidelines for East Asian patients. Therefore, in this article, we will review various issues regarding DAPT in East Asian patients, with a focus on the unique characteristics of East Asian patients, previous studies regarding antiplatelet agents in East Asian patients, and a guideline from an East Asian perspective.

PURPOSE: An attempt was made to characterize the orbital shear stress by comparing the effects of orbital shear stress on vascular endothelial cells (ECs) with the results of animal experiments. MATERIALS AND METHODS: In the laboratory study, cultured ECs of well were distinguished by center and periphery then exposed to orbital shear stress using an orbital shaker. In the animal study, arteriovenous (AV) fistulas were made at the right femoral arteries of Sprague-Dawley rats to increase the effect of the laminar flow. The condition of the stenosis was given on the left femoral arteries. The protein expression of inducible nitric oxide synthase (iNOS) and Akt phosphorylation were observed and compared. RESULTS: Under orbital shear stress, ECs showed an increase in iNOS protein expression and phosphorylation of Akt but most of the protein expressions derived from the periphery. When compared to the animal study, the increased expression of iNOS protein and phosphorylation of Akt were observed in the sample of AV fistula conditions and the iNOS protein expression was decreased in the stenosis conditions. CONCLUSION: Orbital shear stress did not show the characteristics of a pure turbulent shear force. By comparing the observation with the morphological changes of vascular ECs and site-specific protein expression on the results of animal experiments, uniform directional lamina shear stress forces were expressed at the periphery.
Animal Experimentation ; Animals ; Constriction, Pathologic ; Endothelial Cells* ; Femoral Artery ; Fistula ; Nitric Oxide Synthase ; Nitric Oxide Synthase Type II ; Orbit* ; Phosphorylation ; Rats* ; Rats, Sprague-Dawley

Background The benefit of statin use after acute ST-segment elevation myocardial infarction (STEMI) has been well established, however, the influence of the timing of statin administration has not been elucidated. The objective of this study focused on early clinical outcomes after percutaneous coronary intervention (PCI). Methods This analysis of the Korea Working Group on Myocardial Infarction registry (KorMI) study included 3,584 STEMI patients (mean age, 63 ±13 years;male, 2,684, 74.9%) undergoing PCI from January 2008 to June 2009. Rates of major adverse cardiac events (MACE:all-cause death, recurrent MI, and target lesion revascularization) were compared among patients grouped according to statin therapy timing:I, both during and after hospitalization (n=2,653, 74%);II, only during hospita-lization (n=309, 8.6%);III, only after discharge (n=157, 4.4%);and IV, no statin therapy (n=465, 13%). Mean follow-up duration was 234 ± 113 days. Results Multivariate factors of statin use during hospitalization included prior statin use, multiple diseased vessels, final thrombolysis in myocardial infarction flow grade III, and low-density lipoprotein cholesterol level. At 6-month follow-up, groups III and IV had the highest MACE rates (2.3%, 3.9%, 5.1%, and 4.9%for groups I-IV, respectively, P=0.004). After adjusting for confounders, groups II-IV had a higher MACE risk than group I [hazard ratio (HR):3.20, 95%confidence interval (95%CI):1.31-7.86, P=0.011;HR:3.84, 95%CI:1.47-10.02, P=0.006;and HR:3.17, 95%CI:1.59-6.40, P=0.001;respectively]. Conclusions This study, based on the national registry database, shows early and continuous statin therapy improvs early outcomes of STEMI patients after PCI in real-world clinical prac-tice.

Vascular smooth muscle cells (VSMCs) undergo phenotypic changes in response to vascular injury such as angioplasty. Protein kinase G (PKG) has an important role in the process of VSMC phenotype switching. In this study, we examined whether rosiglitazone, a peroxisome proliferator-activated receptor (PPAR)-gamma agonist, could modulate VSMC phenotype through the PKG pathway to reduce neointimal hyperplasia after angioplasty. In vitro experiments showed that rosiglitazone inhibited the phenotype change of VSMCs from a contractile to a synthetic form. The platelet-derived growth factor (PDGF)-induced reduction of PKG level was reversed by rosiglitazone treatment, resulting in increased PKG activity. This increased activity of PKG resulted in phosphorylation of vasodilator-stimulated phosphoprotein at serine 239, leading to inhibited proliferation of VSMCs. Interestingly, rosiglitazone did not change the level of nitric oxide (NO) or cyclic guanosine monophosphate (cGMP), which are upstream of PKG, suggesting that rosiglitazone influences PKG itself. Chromatin immunoprecipitation assays for the PKG promoter showed that the activation of PKG by rosiglitazone was mediated by the increased binding of Sp1 on the promoter region of PKG. In vivo experiments showed that rosiglitazone significantly inhibited neointimal formation after balloon injury. Immunohistochemistry staining for calponin and thrombospondin showed that this effect of rosiglitazone was mediated by modulating VSMC phenotype. Our findings demonstrate that rosiglitazone is a potent modulator of VSMC phenotype, which is regulated by PKG. This activation of PKG by rosiglitazone results in reduced neointimal hyperplasia after angioplasty. These results provide important mechanistic insight into the cardiovascular-protective effect of PPARgamma.
Animals ; Aorta/injuries/metabolism/*pathology ; Calcium-Binding Proteins/genetics/metabolism ; Cell Proliferation ; Cyclic GMP/metabolism ; Cyclic GMP-Dependent Protein Kinases/genetics/*metabolism ; Hyperplasia/metabolism ; Microfilament Proteins/genetics/metabolism ; Muscle, Smooth, Vascular/metabolism/pathology ; Myocytes, Smooth Muscle/drug effects/*metabolism ; Nitric Oxide/metabolism ; PPAR gamma/agonists/*metabolism ; Promoter Regions, Genetic ; Rats ; Rats, Sprague-Dawley ; Sp1 Transcription Factor/metabolism ; Thiazolidinediones/pharmacology ; Thrombospondins/genetics/metabolism ; Tunica Intima/metabolism/*pathology ; Vascular System Injuries/*metabolism/pathology

BACKGROUND AND OBJECTIVES: Intravascular ultrasound (IVUS) is helpful during percutaneous coronary intervention (PCI), because it can be used to confirm good apposition or optimal expansion of stents. In this study, we compared angiographic result as well as clinical outcomes between two different strategies of IVUS-guidance, the selective vs. the routine. SUBJECTS AND METHODS: The study population consisted of 279 patients undergoing electric and emergency intracoronary implatation of TAXUS stent from August 2003 through September 2006. For this study, we divided physicians into two groups; doctors to perform PCI under 'routine' IVUS-guidance vs. PCI under 'selective' IVUS-guidance. Among a total of 279 patients (384 lesions) who underwent PCI with TAXUS stent, 87 patients underwent the procedure under the strategy of 'routine' IVUS-guidance, whereas 192 patients under 'selective' IVUS-guidance. RESULTS: The baseline clinical features of the patients are similar between the two groups. The actual rate of IVUS usage was 89.2% in the routine group and 68.2% in the selective group (p<0.01). A high rate of adjunctive ballooning was determined as a remarkable procedure-related parameter which was comparable between the two groups (72.5% vs. 76.1% in routine vs. selective, p=0.57). The minimal lumen diameter at immediate post-PCI was significantly larger in the routine IVUS group than that in the selective group (2.58 mm vs. 2.48 mm, p=0.03). However, the difference disappeared during the follow-up period (1.98 mm vs. 1.98 mm, p=0.94). Clinical outcomes at 1 year were not different between the two groups. CONCLUSION: PCI under the strategy of 'selective' IVUS-guidance was comparable to PCI under 'routine' IVUS-guidance in terms of angiographic and clinical outcomes in circumstances with frequent use of adjunctive ballooning after stenting.
Drug-Eluting Stents ; Emergencies ; Follow-Up Studies ; Humans ; Percutaneous Coronary Intervention ; Stents ; Taxus ; Ultrasonography, Interventional

Cardiovascular disease has been one of leading causes of death and has an increasing importance in Korea. However the current treatment modalities for cardiovascular disease have limited efficacy. To overcome the limitations of current therapies, stem cell therapy has been evaluated as a new therapeutic option. Most experience and achievements of stem cell therapy for clinical applications have come from bone marrow-derived stem cells. Recent meta-analyses showed that stem cell therapy is safe and effective for improving cardiac systolic functions in patients with acute myocardial infarction. However, the long term efficacy and effects on clinical outcomes need to be determined. Stem cell therapy for acute cardiovascular disease, especially for acute myocardial infarction, has a proven efficacy and safety in short term follow up. Newer stem cell sources and therapeutic approaches such as adjunctive therapy or pretransplantation cultivation will be applied in this field to improve the efficacy of stem cell therapy. Stem cell therapy is a promising new therapeutic option for cardiovascular disease.
Achievement ; Cardiovascular Diseases ; Cause of Death ; Humans ; Korea ; Myocardial Infarction ; Stem Cells

BACKGROUND AND OBJECTIVES: The drug-eluting balloon (DEB) catheter system was developed to treat restenosis. Furthermore, DEB angioplasty has been shown to reduce restenosis risk when compared to drug-eluting stents (DES) in patients with in-stent restenosis (ISR) or small vessel disease (SVD). In addition, DEB angioplasty reduces costs due to fewer revascularizations and reduced clopidogrel treatment length. The objective of this study was to predict the expected cost-savings when DEB is substituted for DES in patients with ISR or SVD. SUBJECTS AND METHODS: The subjects included were patients treated by DES at Seoul National University Hospital from January 2006 to June 2009, with clinical data after percutaneous coronary intervention, were. A model was developed to allow the costs of DES and the calculated costs of DEB incurred by patients with ISR or SVD to be compared. The overall cost of DEB was calculated to be 1,256,150 won and the overall cost of DES was 2,102,500 won, and the cost of clopidogrel was 2,168 won. Expected repeat revascularizations within 12 months of DEB were calculated based on information provided by the Paclitaxel-Eluting PTCA-Balloon Catheter in Coronary Artery (PEPCAD) I and II trials. RESULTS: By substituting DEB for DES, total cost (including the cost of initial DEB treatment, the cost of repeat revascularization after DEB treatment, and the cost of clopidogrel treatment) was found to be 34% lower in ISR patients and 48% lower in SVD patients. CONCLUSION: DEB angioplasty will significantly reduce costs as compared to DES in ISR and in SVD patients.
Angioplasty ; Angioplasty, Balloon ; Catheters ; Coronary Restenosis ; Coronary Vessels ; Drug-Eluting Stents ; Glycosaminoglycans ; Humans ; Percutaneous Coronary Intervention ; Ticlopidine

This study compared two-stent strategies for treatment of bifurcation lesions by stenting order, 'main across side first (A-family)' vs 'side branch first (S-family). The study population was patients from 16 centers in Korea who underwent drug eluting stent implantation with two-stent strategy (A-family:109, S-family:140 patients). The endpoints were cardiac death, myocardial infarction (MI), stent thrombosis (ST), and target lesion revascularization (TLR) during 3 years. During 440.8 person-years (median 20.2 months), there was 1 cardiac death, 4 MIs (including 2 STs), and 12 TLRs. Cumulative incidence of cardiac death, MI and ST was lower in A-family (0% in A-family vs 4.9% in S-family, P = 0.045). However, TLR rates were not different between the two groups (7.1% vs 6.2%, P = 0.682). Final kissing inflation (FKI) was a predictor of the hard-endpoint (hazard ratio 0.061; 95% CI 0.007-0.547, P = 0.013), but was not a predictor of TLR. The incidence of hard-endpoint of S-family with FKI was comparable to A-family, whereas S-family without FKI showed the poorest prognosis (1.1% vs 15.9%, retrospectively; P = 0.011). In conclusion, 'A-family' seems preferable to 'S-family' if both approaches are feasible. When two-stent strategy is used, every effort should be made to perform FKI, especially in 'S-family'.
Aged ; Angioplasty, Balloon, Coronary/*methods ; Coronary Stenosis/surgery/*therapy ; Death, Sudden, Cardiac/etiology ; *Drug-Eluting Stents ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Myocardial Infarction/etiology ; Myocardial Revascularization ; Thrombosis/etiology

BACKGROUND AND OBJECTIVES: The prevalence of arthritis, which is often treated with celecoxib, is high in patients with coronary artery disease. Furthermore, celecoxib has been reported to reduce restenosis after coronary stenting by inhibiting expression of the proto-oncogene Akt. A concern is that celecoxib increases thrombogenicity by inhibiting the synthesis of prostacyclin in endothelial cells. However, it is not known whether the administration of celecoxib will attenuate the antiplatelet effects of aspirin and clopidogrel, which are used after stenting. We addressed this gap in our knowledge. SUBJECTS AND METHODS: We recruited healthy volunteers (n=40) and randomized them into five subgroups (n=8 for each group: aspirin, celecoxib, aspirin+celecoxib, aspirin+clopidogrel, and aspirin+clopidogrel+celecoxib). Each subject received their medications for 6 days and blood samples were taken on day 0 and day 7. Celecoxib (200 mg twice a day), and/or aspirin (100 mg daily), and/or clopidogrel (75 mg daily) were administered. We compared platelet function among subgroups using light transmittance aggregometry and arachidonic acid metabolite assays. RESULTS: Celecoxib treatment alone did not significantly affect platelet aggregation. The reduction in adenosine diphosphase (ADP)-induced platelet aggregation by aspirin+clopidogrel was not affected by addition of celecoxib (31.3+/-6.9% vs. 32.4+/-12.2%, p=0.83). Inhibition of collagen-induced platelet aggregation by aspirin+clopidogrel was not affected by addition of celecoxib (47.6+/-13.4% vs. 51.6+/-3.7%, p=0.69). Drug-induced changes in prostacyclin and thromboxane levels did not differ among treatment groups. CONCLUSION: Celecoxib treatment does not interfere with the antiplatelet effects of aspirin or clopidogrel, suggesting that celecoxib can be safely administered in combination with dual antiplatelet therapy in patients with coronary stenting without increased thrombogenicity.
Adenosine ; Arachidonic Acid ; Arthritis ; Aspirin ; Blood Platelets ; Coronary Artery Disease ; Endothelial Cells ; Epoprostenol ; Humans ; Light ; Platelet Aggregation ; Platelet Aggregation Inhibitors ; Prevalence ; Proto-Oncogenes ; Pyrazoles ; Stents ; Sulfonamides ; Thrombosis ; Celecoxib ; Ticlopidine