Si-Hoon Park

Reduction in Visceral Adiposity is Highly Related to Improvement in Vascular Endothelial Dysfunction among Obese Women: An Assessment of Endothelial Function by Radial Artery Pulse Wave Analysis

Because obesity is frequently complicated by other cardiovascular risk factors, the impact of a reduction in visceral adiposity on vascular endothelial dysfunction (VED) in obese patients is difficult to determine. In the present study, we evaluated the impact of a reduction in visceral adiposity on VED in obese women. Thirty-six premenopausal obese women (BMI ≥ 25 kg/m2) without complications were enrolled in the study. VED was evaluated by determining the augmentation index (AIx) from radial artery pulse waves obtained by applanation tonometry. Changes in AIx in response to nitroglycerin-induced endothelium-independent vasodilatation (ΔAIx-NTG) and in response to salbutamol administration (ΔAIx-Salb) were determined before and after weight reduction. After a 12-week weight reduction program, the average weight loss was 7.96±3.47 kg, with losses of 21.88±20.39 cm2 in visceral fat areas (p < 0.001). Pulse wave analysis combined with provocative pharmacological testing demonstrated preserved endothelium-independent vasodilation in healthy premenopausal obese women (ΔAIx-NTG: 31.36±9.80% before weight reduction vs. 28.25 ± 11.21% after weight reduction, p > 0.1) and an improvement in endothelial-dependent vasodilation following weight reduction (ΔAIx-Salb: 10.03±6.49% before weight reduction vs. 19.33 ± 9.28% after reduction, p < 0.001). A reduction in visceral adipose tissue was found to be most significantly related to an increase in ΔAIx-Salb (β=-0.57, p < 0.001). A reduction in visceral adiposity was significantly related to an improvement in VED. This finding suggests that reduction of visceral adiposity may be as important as the control of other major risk factors in the prevention of atherosclerosis in obese women.

Evaluation of the Dose-Response Relationship of Amlodipine and Losartan Combination in Patients with Essential Hypertension

BackgroundDespite recommendations for more intensive treatment and the availability of several effective treatments, hypertension remains uncontrolled in many patients.ObjectiveThe aim of this study was to determine the dose-response relationship and assess the efficacy and safety of amlodipine or losartan monotherapy and amlodipine camsylate/losartan combination therapy in patients with essential hypertension.MethodsThis was an 8-week, randomized, double-blind, factorial design, phase II, multicenter study conducted in outpatient hospital clinics among adult patients aged 18–75 years with essential hypertension. At screening, patients received placebo for 2–4 weeks. Eligible patients (n = 320) were randomized to one of eight treatment groups: amlodipine 5 mg or 10 mg, losartan 50 mg or 100 mg, amlodipine camsylate/losartan 5 mg/50 mg, 5 mg/100 mg, 10 mg/50 mg, or 10 mg/100 mg.Main Outcome MeasuresThe assumption of strict superiority was estimated using the mean change in sitting diastolic blood pressure (DBP) at 8 weeks. Safety was monitored through physical examinations, vital signs, laboratory test results, ECG, and adverse events.ResultsThe reduction in DBP at 8 weeks was significantly greater in patients treated with the combination therapies compared with the respective monotherapies for all specified comparisons except amlodipine camsylate/losartan 10 mg/100 mg versus amlodipine 10mg. The incidence of adverse events in the group of patients treated with the amlodipine camsylate/losartan 10 mg/50 mg combination tended to be higher than for any other group (27.9%, 12/43); however, the effect was not statistically significant.ConclusionCombination amlodipine camsylate/losartan (5 mg/50 mg, 5 mg/100 mg and 10 mg/50 mg) resulted in significantly greater BP lowering compared with amlodipine or losartan monotherapy, and was determined to be generally safe and tolerable in patients with essential hypertension.Clinical Trial RegistrationRegistered at clinicaltrials.gov: NCT00942344.

The Effect of Doubling the Statin Dose on Pro-Inflammatory Cytokine in Patients With Triple-Vessel Coronary Artery Disease

Background and Objectives Statin prevents atherosclerotic progression and helps to stabilize the plaque. According to a recent study, statin reduces inflammation in blood vessels. However, it has not been demonstrated to have any anti-inflammation reaction in patients who have been diagnosed as having a triple-vessel coronary artery disease (CAD). Subjects and Methods This study included a total of thirty (30) patients who had been diagnosed by coronary angiogram as having a triple-vessel CAD. Patients who already had been taking statin were given doubled dosage. An interview, physical examination and blood test were performed at the beginning of this study and three months later. Results After doubling the dose of statin, there was no statistically significant decrease in total cholesterol, low density lipoprotein-cholesterol, (increase in) high density lipoprotein-cholesterol and triglyceride in the blood test. C-reactive protein (CRP), an acute phase reactant, significantly decreased from 0.34 mg/dL at the beginning of the study to 0.12 mg/dL at the end of study (p<0.01). The interleukin-6 concentration also significantly decreased from 8.55 pg/dL to 4.81 pg/dL (p<0.001). No major cardiovascular events occurred and the dosage regimen was not modified during the close observation period. There was no difference in the symptoms of angina pectoris, established by World Health Organization Angina Questionnaires, before and after the dose increase. Liver enzymes remained within normal range with no significant increase before and after conducting this study. Conclusion Doubling the dose of statin alone significantly lowers pro-inflammatory cytokine concentration, which is closely related to the potential acute coronary syndrome, and CRP, a marker of vascular inflammation.

Six-Month Versus 12-Month Dual Antiplatelet Therapy After Implantation of Drug-Eluting Stents

Background— The optimal duration of dual antiplatelet therapy (DAPT) after implantation of drug-eluting coronary stents remains undetermined. We aimed to test whether 6-month DAPT would be noninferior to 12-month DAPT after implantation of drug-eluting stents. Methods and Results— We randomly assigned 1443 patients undergoing implantation of drug-eluting stents to receive 6- or 12-month DAPT (in a 1:1 ratio). The primary end point was a target vessel failure, defined as the composite of cardiac death, myocardial infarction, or ischemia-driven target vessel revascularization at 12 months. Rates of target vessel failure at 12 months were 4.8% in the 6-month DAPT group and 4.3% in the 12-month DAPT group (the upper limit of 1-sided 95% confidence interval, 2.4%; P =0.001 for noninferiority with a predefined noninferiority margin of 4.0%). Although stent thrombosis tended to occur more frequently in the 6-month DAPT group than in the 12-month group (0.9% versus 0.1%; hazard ratio, 6.02; 95% confidence interval, 0.72–49.96; P =0.10), the risk of death or myocardial infarction did not differ in the 2 groups (2.4% versus 1.9%; hazard ratio, 1.21; 95% confidence interval, 0.60–2.47; P =0.58). In the prespecified subgroup analysis, target vessel failure occurred more frequently in the 6-month DAPT group than in the 12-month group (hazard ratio, 3.16; 95% confidence interval, 1.42–7.03; P =0.005) among diabetic patients. Conclusions— Six-month DAPT did not increase the risk of target vessel failure at 12 months after implantation of drug-eluting stents compared with 12-month DAPT. However, the noninferiority margin was wide, and the study was underpowered for death or myocardial infarction. Our results need to be confirmed in larger trials. Clinical Trial Registration— URL: . Unique identifier: [NCT00698607][1]. # Clinical Perspective {#article-title-31} [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT00698607&atom=%2Fcirculationaha%2F125%2F3%2F505.atomBackground— The optimal duration of dual antiplatelet therapy (DAPT) after implantation of drug-eluting coronary stents remains undetermined. We aimed to test whether 6-month DAPT would be noninferior to 12-month DAPT after implantation of drug-eluting stents. Methods and Results— We randomly assigned 1443 patients undergoing implantation of drug-eluting stents to receive 6- or 12-month DAPT (in a 1:1 ratio). The primary end point was a target vessel failure, defined as the composite of cardiac death, myocardial infarction, or ischemia-driven target vessel revascularization at 12 months. Rates of target vessel failure at 12 months were 4.8% in the 6-month DAPT group and 4.3% in the 12-month DAPT group (the upper limit of 1-sided 95% confidence interval, 2.4%; P=0.001 for noninferiority with a predefined noninferiority margin of 4.0%). Although stent thrombosis tended to occur more frequently in the 6-month DAPT group than in the 12-month group (0.9% versus 0.1%; hazard ratio, 6.02; 95% confidence interval, 0.72–49.96; P=0.10), the risk of death or myocardial infarction did not differ in the 2 groups (2.4% versus 1.9%; hazard ratio, 1.21; 95% confidence interval, 0.60–2.47; P=0.58). In the prespecified subgroup analysis, target vessel failure occurred more frequently in the 6-month DAPT group than in the 12-month group (hazard ratio, 3.16; 95% confidence interval, 1.42–7.03; P=0.005) among diabetic patients. Conclusions— Six-month DAPT did not increase the risk of target vessel failure at 12 months after implantation of drug-eluting stents compared with 12-month DAPT. However, the noninferiority margin was wide, and the study was underpowered for death or myocardial infarction. Our results need to be confirmed in larger trials. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00698607.

Predictors and Long-Term Clinical Outcome of Longitudinal Stent Deformation: Insights From Pooled Analysis of Korean Multicenter Drug-Eluting Stent Cohort

Background— There are limited data on the frequency of and factors associated with quantitative coronary angiography (QCA)–defined longitudinal stent deformation (LSD) in various contemporary drug-eluting stents platforms. This study sought to evaluate the predictors of LSD and its long-term clinical implication. Methods and Results— A patient-level pooled analysis was performed with 7350 lesions in 5871 patients treated with platinum-chromium–based everolimus-eluting stent (Promus Element), cobalt-chromium–based everolimus-eluting stent (Promus/Xience V), or cobalt-chromium–based zotarolimus-eluting stent (Endeavor Resolute). QCA was performed to analyze differences of stent length between immediate post-deployment and final post-procedure. Independent factors associated with LSD were identified. Clinical outcomes at 3 years were compared between those with and without QCA-based LSD. The frequency of QCA-based LSD was 1.12% (82 cases). Nine of these cases were angiographically overt. Left main or ostial lesion, bifurcation treatment with provisional side branch stenting or ballooning, additional downstream intervention of a distal lesion, intravascular ultrasound use, and adjunctive post-dilatation were independently associated with QCA-based LSD. The type of stent was not associated with QCA-based LSD. Rates of target lesion failure were nominally higher in lesions with QCA-based LSD than in those without (8.97% versus 5.88%; hazard ratio, 1.415; 95% confidence interval, 0.631–3.175; P=0.399). Conclusions— LSD is uncommon with contemporary drug-eluting stents, regardless of the type of stent platform. LSD is mainly associated with procedural factors, especially with additional downstream procedures which require the passage of devices through the stent. Careful manipulation of poststent imaging or procedural devices is required to prevent LSD. More data are needed to clarify the impact of LSD on clinical events.

Six-Month Versus 12-Month Dual Antiplatelet Therapy After Implantation of Drug-Eluting StentsClinical Perspective

Background— The optimal duration of dual antiplatelet therapy (DAPT) after implantation of drug-eluting coronary stents remains undetermined. We aimed to test whether 6-month DAPT would be noninferior to 12-month DAPT after implantation of drug-eluting stents. Methods and Results— We randomly assigned 1443 patients undergoing implantation of drug-eluting stents to receive 6- or 12-month DAPT (in a 1:1 ratio). The primary end point was a target vessel failure, defined as the composite of cardiac death, myocardial infarction, or ischemia-driven target vessel revascularization at 12 months. Rates of target vessel failure at 12 months were 4.8% in the 6-month DAPT group and 4.3% in the 12-month DAPT group (the upper limit of 1-sided 95% confidence interval, 2.4%; P =0.001 for noninferiority with a predefined noninferiority margin of 4.0%). Although stent thrombosis tended to occur more frequently in the 6-month DAPT group than in the 12-month group (0.9% versus 0.1%; hazard ratio, 6.02; 95% confidence interval, 0.72–49.96; P =0.10), the risk of death or myocardial infarction did not differ in the 2 groups (2.4% versus 1.9%; hazard ratio, 1.21; 95% confidence interval, 0.60–2.47; P =0.58). In the prespecified subgroup analysis, target vessel failure occurred more frequently in the 6-month DAPT group than in the 12-month group (hazard ratio, 3.16; 95% confidence interval, 1.42–7.03; P =0.005) among diabetic patients. Conclusions— Six-month DAPT did not increase the risk of target vessel failure at 12 months after implantation of drug-eluting stents compared with 12-month DAPT. However, the noninferiority margin was wide, and the study was underpowered for death or myocardial infarction. Our results need to be confirmed in larger trials. Clinical Trial Registration— URL: . Unique identifier: [NCT00698607][1]. # Clinical Perspective {#article-title-31} [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT00698607&atom=%2Fcirculationaha%2F125%2F3%2F505.atomBackground— The optimal duration of dual antiplatelet therapy (DAPT) after implantation of drug-eluting coronary stents remains undetermined. We aimed to test whether 6-month DAPT would be noninferior to 12-month DAPT after implantation of drug-eluting stents. Methods and Results— We randomly assigned 1443 patients undergoing implantation of drug-eluting stents to receive 6- or 12-month DAPT (in a 1:1 ratio). The primary end point was a target vessel failure, defined as the composite of cardiac death, myocardial infarction, or ischemia-driven target vessel revascularization at 12 months. Rates of target vessel failure at 12 months were 4.8% in the 6-month DAPT group and 4.3% in the 12-month DAPT group (the upper limit of 1-sided 95% confidence interval, 2.4%; P=0.001 for noninferiority with a predefined noninferiority margin of 4.0%). Although stent thrombosis tended to occur more frequently in the 6-month DAPT group than in the 12-month group (0.9% versus 0.1%; hazard ratio, 6.02; 95% confidence interval, 0.72–49.96; P=0.10), the risk of death or myocardial infarction did not differ in the 2 groups (2.4% versus 1.9%; hazard ratio, 1.21; 95% confidence interval, 0.60–2.47; P=0.58). In the prespecified subgroup analysis, target vessel failure occurred more frequently in the 6-month DAPT group than in the 12-month group (hazard ratio, 3.16; 95% confidence interval, 1.42–7.03; P=0.005) among diabetic patients. Conclusions— Six-month DAPT did not increase the risk of target vessel failure at 12 months after implantation of drug-eluting stents compared with 12-month DAPT. However, the noninferiority margin was wide, and the study was underpowered for death or myocardial infarction. Our results need to be confirmed in larger trials. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00698607.