Byoung Kwon Lee

Endovascular Therapy Combined with Immunosuppressive Treatment for Pseudoaneurysms in Patients with Behçet's Disease:

PURPOSE To evaluate the feasibility, efficacy, and outcome of endovascular therapy combined with immunosuppression for the treatment of arterial pseudoaneurysms due to Behçets disease. METHODS Eleven pseudoaneurysms (3 in the abdominal aorta, 3 in the subclavian artery, and individual lesions in the brachiocephalic artery, renal artery, common iliac artery, common carotid artery, and the descending thoracic aorta) in 9 patients with Behçets disease were treated with 10 stent-grafts and 1 self-expanding stent. All patients with elevated erythrocyte sedimentation rate (ESR) were treated with immunosuppressive agents (azathioprine, prednisolone) before and after the procedure. RESULTS Endovascular treatment was successful in all cases, without major adverse events. The ESR was reduced from 42.7+/-18.0 mm/h initially to 18.6+/-12.6 mm/h after immunosuppressive therapy prior to endovascular repair. During follow-up (mean 24.1+/-14.0 months, range 6-43), 8 of 11 lesions showed complete resolution. One stent-graft to treat a postsurgical recurrent carotid artery pseudoaneurysm was occluded, and an abdominal aortic pseudoaneurysm recurred; both patients stopped their medications. ESR during follow-up was 7.9+/-4.5 mm/h. CONCLUSIONS Endovascular treatment for pseudoaneurysms due to Behçets disease is feasible and effective when disease activity is strictly controlled with immunosuppressive therapy.

Impact of Metabolic Syndrome and Its Individual Components on the Presence and Severity of Angiographic Coronary Artery Disease

Purpose Metabolic syndrome (MS) has been reported as a potential risk factor of coronary artery disease (CAD). The aims of this study were to assess whether there was a relationship between MS score and CAD angiographic severity, and to assess the predictive value of individual components of MS for CAD. Materials and Methods We retrospectively enrolled 632 patients who underwent coronary angiography for suspected CAD (394 men, 61.0 ± 10.6 years of age). MS was defined by the National Cholesterol Education Program criteria with the waist criterion modified into a body mass index (BMI) of more than 25 kg/m2. The MS score defined as the number of MS components. CAD was defined as > 50% luminal diameter stenosis of at least one major epicardial coronary artery. CAD angiographic severity was evaluated with a Gensini scoring system. Results Of the patients, 497 (78.6%) had CAD and 283 (44.8%) were diagnosed with MS. The MS score was significantly related to the Gensini score. High fasting blood glucose (FBG) was the only predictive factor for CAD. A cluster including high FBG, high blood pressure (BP), and low high-density lipoprotein cholesterol (HDL-C) showed the highest CAD risk. Conclusion The MS score correlates with the angiographic severity of CAD. The predictive ability of MS for CAD was carried almost completely by high FBG, and individual traits with high BP and low HDL-C may act synergistically as risk factors for CAD.

Local increase in microparticles from the aspirate of culprit coronary arteries in patients with ST-segment elevation myocardial infarction.

OBJECTIVE It has been reported that the levels of procoagulant microparticles (MPs) are increased in patients with acute coronary syndromes and this may contribute to the formation of intracoronary thrombi. In the current study, we investigated the presence of locally elevated MPs within the culprit coronary arteries of patients with ST-segment elevation myocardial infarction (STEMI). METHODS The study population consisted of 45 patients with STEMI who underwent primary percutaneous coronary intervention (PCI), and 16 control patients. Before and after PCI, blood samples were collected from the femoral artery and from the culprit coronary arteries. In controls, only peripheral blood was obtained. MPs were measured by a solid-phase capture assay using a commercial kit. The cell origins of MPs were determined by antigenic capture with specific antibodies. RESULTS Baseline levels of MPs in patients with STEMI were higher than in controls. Before PCI, the levels of MPs were significantly higher in culprit coronary arteries than in peripheral arteries in STEMI patients (20.7 ± 15.5 vs. 14.6 ± 15.4 nM phosphatidylserine (PS) equivalent, p = 0.027). MPs from the culprit coronary artery were significantly reduced after PCI (20.7 ± 15.5 vs. 14.3 ± 14.9 nM PS equivalent, p = 0.010). Similarly, the locally increased levels of endothelial- and platelet-derived MPs within the culprit coronary arteries were significantly decreased after PCI. CONCLUSION Locally increased levels of MPs in culprit coronary arteries and their significant reduction after successful PCI suggest a potential role in coronary atherothrombosis in the early period of STEMI.

Incidence and natural history of coronary artery aneurysm developing after drug-eluting stent implantation.

AIMS There is a growing concern about the occurrence of coronary artery aneurysms (CAAs) after drug-eluting stent (DES) implantation and their long-term course. We assessed the occurrence and the factors affecting the long-term outcome of DES-associated CAA. METHODS AND RESULTS We analyzed 3,612 consecutive patients (4,419 lesions) who underwent follow-up angiography after DES implantation. All 34 CAAs (0.76% per lesion) in 29 patients (0.8% per patient) were detected at follow-up, and the mean elapsed time from DES implantation to CAA diagnosis was 414 ± 213 days. Angiographically, CAAs developed almost exclusively in complex (type B2/C) de novo lesions (30 [88.2%] of 34 lesions), and lesion length was significantly greater in patients with CAA than without CAA (26.9 ± 9.03 vs 23.1 ± 7.14 mm; P = .004). Myocardial infarction with stent thrombosis occurred in 5 patients with CAA (17.2%), 4 of whom were on aspirin only without clopidogrel. CONCLUSION Although CAAs rarely develop after DES implantation and show mostly favorable clinical courses, long-term maintenance of clopidogrel therapy might be required to minimize occurrence of adverse clinical events resulting from stent thrombosis.

Clinical Feasibility of 3D Automated Coronary Atherosclerotic Plaque Quantification Algorithm on Coronary Computed Tomography Angiography: Comparison with Intravascular Ultrasound.

ObjectiveTo evaluate the diagnostic performance of automated coronary atherosclerotic plaque quantification (QCT) by different users (expert/non-expert/automatic).MethodsOne hundred fifty coronary artery segments from 142 patients who underwent coronary computed tomography angiography (CCTA) and intravascular ultrasound (IVUS) were analyzed. Minimal lumen area (MLA), maximal lumen area stenosis percentage (%AS), mean plaque burden percentage (%PB), and plaque volume were measured semi-automatically by expert, non-expert, and fully automatic QCT analyses, and then compared to IVUS.ResultsBetween IVUS and expert QCT analysis, the correlation coefficients (r) for the MLA, %AS, %PB, and plaque volume were excellent: 0.89 (p < 0.001), 0.84 (p < 0.001), 0.91 (p < 0.001), and 0.94 (p < 0.001), respectively. There were no significant differences in the mean parameters (all p values >0.05) except %AS (p = 0.01). The automatic QCT analysis showed comparable performance to non-expert QCT analysis, showing correlation coefficients (r) of the MLA (0.80 vs. 0.82), %AS (0.82 vs. 0.80), %PB (0.84 vs. 0.73), and plaque volume (0.84 vs. 0.79) when they were compared to IVUS, respectively.ConclusionFully automatic QCT analysis showed clinical utility compared with IVUS, as well as a compelling performance when compared with semiautomatic analyses.Key Points• Coronary CTA enables the assessment of coronary atherosclerotic plaque.• High-risk plaque characteristics and overall plaque burden can predict future cardiac events.• Coronary atherosclerotic plaque quantification is currently unfeasible in practice.• Quantitative computed tomography coronary plaque analysis software (QCT) enables feasible plaque quantification.• Fully automatic QCT analysis shows excellent performance.

Pathobiological role of advanced glycation endproducts via mitogen-activated protein kinase dependent pathway in the diabetic vasculopathy

Advanced glycation endproducts (AGEs) have been reported to play a role in neointimal formation and increase the rate of in-stent restenosis (ISR) in the diabetic coronary artery disease patients treated with stents, but the potential pathogenic mechanisms of AGEs in vascular smooth muscle cell proliferation remain unclear. We sought to determine the AGEs related pathobiological mechanism of diabetic vasculopathy. Rat aortic smooth muscle cell (RAoSMC) culture was done with different concentrations of AGEs and proliferation was assessed. Immunohistochemistry for receptor of AGEs (RAGE) was performed with human carotid atheroma. Western blotting was performed to assess the activation of MAP kinase system in the cultured RAoSMC. AGEs increased RAoSMC proliferation and were associated with increased phosphorylation of ERK and p38 kinase by time and dose dependent manner. The MAP kinase activity was decreased by RNA interference for RAGE. AGEs stimulation increased reactive oxygen species (ROS) generation in cultured RAoSMC. From this study it is concluded that AGEs played a key role in RAoSMC proliferation via MAP kinase dependent pathways. Activation of vascular smooth muscle cell (VSMC) proliferation by MAP kinase system and increased formation of ROS may be the possible mechanisms of AGEs induced diabetic vasculopathy.

Comparison of sirolimus-eluting stent and paclitaxel-eluting stent for long-term cardiac adverse events in diabetic patients: the Korean Multicenter Angioplasty Team (KOMATE) Registry.

Background: There is some controversy on long‐term cardiac outcomes between sirolimus‐eluting stents (SES) and paclitaxel‐eluting stents (PES) in diabetes mellitus (DM). We compared cardiac adverse events after SES and PES implantation in patients with DM over a period of 3 year. Methods: A total of 634 patients with DM treated with SES (n = 428) or PES (n = 206) were consecutively enrolled in the KOMATE registry from 2003 to 2004. We assessed major adverse cardiac events (MACEs, cardiovascular death, nonfatal myocardial infarction, ischemia driven target vessel revascularization) and stent thrombosis (ST) according to the definitions set by the Academic Research Consortium. Results: Propensity score (PS) analysis was performed to adjust different baseline characteristics. The mean follow‐up duration was 38 ± 8 month (at least 36 month and up to 53 month). The 3‐year MACE rate did not show a significant difference between the two groups [52 (12.1%) in SES vs. 29 (14.1%) in PES, P = 0.496]. The definite and probable ST at 3 year were similar in both SES and PES [12 (2.8%) in SES vs. 7 (3.4%) in PES, P = 0.681]. There were no differences in hazard ratio for MACE and ST between two stents [MACE, crude: 0.844 (0.536–1.330) and adjusted for PS: 0.858 (0.530–1.389); ST, crude: 0.820 (0.323–2.083) and adjusted for PS: 0.960 (0.357–2.587)]. Conclusions: The present study demonstrated that long‐tem cardiac outcomes including ST were not significantly different between SES and PES in patients with DM.

The 24-Month Prognosis of Patients With Positive or Intermediate Results in the Intracoronary Ergonovine Provocation Test.

OBJECTIVES This study was an observational, multicenter registry to determine clinical characteristics and 24-month prognosis of patients who underwent intracoronary ergonovine provocation tests. BACKGROUND The clinical characteristics and prognosis of patients who underwent the ergonovine provocation for vasospastic angina were not fully elucidated. METHODS A total of 2,129 patients in the VA-KOREA (Vasospastic Angina in Korea) registry were classified into positive (n = 454), intermediate (n = 982), and negative (n = 693) groups by intracoronary ergonovine provocation tests. The 24-month incidences of cardiac death, new-onset arrhythmia, and acute coronary syndrome were determined (mean 26.7 ± 8.8 months). RESULTS The number of smokers, frequency of angina before angiography, high-sensitivity C-reactive protein, and triglyceride were higher in the positive group than in other groups. The clinical characteristics of the intermediate and the negative groups were very similar. In the positive group, the incidences of diffuse, focal, and mixed spasm were 65.9%, 23.6%, and 10.6%. Coronary spasm was more frequently provoked on atherosclerotic segments. The 24-month incidences of cardiac death, arrhythmia, and acute coronary syndrome were low (0.9%, 1.6%, and 1.9%, respectively) in the positive group, and there was no cardiac death in the intermediate group (p = 0.02). In the positive group, frequent angina, current smoking, and multivessel spasm were independent predictors for adverse events. CONCLUSIONS The 24-month prognosis of the positive group in the intracoronary ergonovine provocation test was relatively worse than that of the intermediate group. More intensive clinical attention should be paid to vasospastic angina patients with high-risk factors including frequent angina before angiography, current smoking, and multivessel spasm.

Non-invasively measured aortic wave reflection and pulse pressure amplification are related to the severity of coronary artery disease

BACKGROUND Augmentation index (AIx) and pulse pressure amplification (PPA, here the aortic/brachial pulse pressure ratio) are an age-related emerging risk factor for cardiovascular disease. However, it has not been clearly shown that AIx and PPA predict a high risk of coronary artery disease (CAD). OBJECTIVES The aim of the study was to investigate the association between non-invasively measured aortic wave reflection (AWR) and PPA and CAD. METHODS The study group consisted of 80 patients who were admitted to our institute for elective coronary angiography. We non-invasively measured augmentation pressure (AP), AIx, and PPA using radial applanation tonometry. RESULTS When the extent of CAD was divided by no or minimal CAD, 1- or 2- and 3-vessel disease (VD), there was a significant association between the extent of CAD and AIx and PPA in patients aged <65 years, but not in patients aged ≥ 65 years. In multivariate regression analysis after controlling the traditional risk factors, the odds ratio of having 3VD was significant in patients aged <65 years: 2.15 (1.04-4.44; p=0.039) per 5% increase of AIx and 2.02 (1.15-3.55; p=0.015) per 0.05 increase of PPA, but not in patients aged ≥ 65 years. The severity of CAD expressed as a Gensini score showed a significant correlation with AP, AIx, and PPA in patients aged <65 years, but not in patients aged ≥ 65 years. CONCLUSION Increasing of non-invasively measured AWR and PPA is related to the severity of CAD, particularly in younger patients up to 65 years of age.

Significance of hemodynamic effects on the generation of atherosclerosis

Atherosclerosis, which is a degenerative vascular disease, is believed to occur in the blood vessels due to deposition of cholesterol or low density hpoprotein (LDL) Atherosclerotic lumen narrowing causes reduction of blood flow due to hemodynamic features Several hypothetical theories related to the hemodynamic effects have been reported. high shear stress theory, low shear stress theory, high shear stress gradient theory, flow separation and turbulence theory, and high pressure theory However, no one theory clearly explains the causes of atherosclerosis The objective of the present study was to investigate the mechanism of the generation of atherosclerosis In the study, the database of Korean carotid and coronary arteries for geometrical and hemodynamic clinical data was established The atherosclerotic sites were predicted by the computer simulations. The results of the computer simulation were compared with the in vivo experimental results, and then the pathogenesis of atherosclerosis by using the clinical data and several hypothetical theories were investigated From the investigation, it was concluded carefully that the mechanism of the generation of atherosclerosis was related to the hemodynamic effects such as flow separation and oscillatory wall shear stress on the vessel walls