The Expression of Transforming Growth Factor-beta1 and alpha-Smooth Muscle Actin is Increased in the Human Myxomatous Valve

BACKGROUND: In vitro experimental studies have reported that transforming growth factor-beta1 (TGF-beta1) stimulates the production of alpha-smooth muscle actin (alpha-SMA) in porcine valves. However, the relation between TGF-beta1 and alpha-SMA in myxomatous valves has not been elucidated. METHODS: We classified 27 subjects into two groups: 1) myxomatous group (M:F=11:12, mean age=55+/-15 years) and 2) rheumatic group (M:F=3:1, mean age=41+/-17 years) according to preoperative echocardiographic and postoperative histologic findings. Twenty-seven valve specimens from the patients who underwent valve replacement were obtained. Tissue samples were analyzed by immunohistochemistry for TGF-beta1 and alpha-SMA. The positively stained areas were measured using an image analysis program (Image Pro-Plus 4.5), and then the TGF-beta1 volume fraction (TGF-VF) and alpha-SMA volume fraction (alpha-SMA-VF) were calculated. RESULTS: TGF-VF in myxomatous valves was higher than in rheumatic valves (2,759+/-2,294 vs 864+/-276, p=0.04). alpha-SMA-VF in myxomatous valves was higher than in rheumatic valves (4,122+/-2,275 vs 2,421+/-844, p=0.002). There was a significant correlation between TGF-beta1 and alpha-SMA in myxomatous valves (r=0.38, p=0.04). There was no significant correlation between TGF-beta1 and alpha-SMA in rheumatic valves (r=-0.50, p=0.67). CONCLUSIONS: TGF-beta1 and alpha-SMA may be related to the pathogenesis of myxomatous valves. The activation of TGF-beta1 might increase the expression of alpha-SMA in human myxomatous valves.

Effect of Angiotensin Converting Enzyme Inhibitors and Angiotensin Receptor Blockers on Patients Following Ablation of Atrial Fibrillation

BACKGROUND AND OBJECTIVES: It is known that angiotensin converting enzyme inhibitors and angiotensin II type 1 receptor blockers (ACEIs and ARBs, respectively) are effective in preventing atrial fibrillation (AF) in high-risk patients. However, it is not known whether ACEIs and ARBs are effective in preventing the recurrence of AF after catheter ablation. SUBJECTS AND METHODS: One hundred fifty-two patients (mean age, 57+/-10 years; M : F=94 : 58) who underwent catheter ablation due to drug-refractory paroxysmal (mean age, 57+/-10 years; M : F=58 : 43) or persistent AF (mean age, 56+/-10 years; M : F=36 : 15) were enrolled. We compared the recurrence rates between the groups with and without ACEIs or ARBs use in paroxysmal and persistent AF. The mean duration of follow-up was 18+/-14 months. RESULTS: The overall recurrence rate after ablation therapy was 26% (n=39). The recurrence rate was significantly decreased in the patients with persistent AF with the use of ACEIs or ARBs (12.1% vs. 61.1%, p<0.01), but this difference was not observed in the patients with paroxysmal AF (24.2% vs. 22.9%, p=0.87). In patients with persistent AF with and without recurrence, the size of the left atrium (44.2+/-8.4 mm vs. 44.3+/-5.8 mm, respectively, p=0.45) and the ejection fraction (62+/-6.5% vs. 61.5+/-6.2%, respectively, p=0.28) were not significantly different. In multivariate analysis, the use of ACEIs or ARBs was independently associated with recurrence after adjusting for the size of the left atrium and the ejection fraction {odds ratio (OR)=0.078, 95% confidence interval (CI)=0.02-0.35, p<0.01}. CONCLUSION:ACEIs and ARBs were shown to be effective in preventing AF recurrence after catheter ablation in patients with persistent AF.

Takayasu's Arteritis Treated by Percutaneous Transluminal Angioplasty with Stenting in the Descending Aorta

A 17-yr-old young woman was referred to our hospital with a 2-yr history of claudication of the lower extremities and severe arterial hypertension. Physical examination revealed significantly different blood pressures between both arms (160/92 and 180/95 mmHg) and legs (92/61 and 82/57 mmHg). The hematological and biochemical values were within their normal ranges, except for the increased erythrocyte sedimentation rate (83 mm/hr) and C-reactive protein (6.19 mg/L). On 3- dimensional computed tomographic angiography, the ascending aorta, the aortic arch and its branches, and the thoracic and, descending aorta, but not the renal artery, were shown to be stenotic. The diagnosis of type IIb Takayasu's arteritis was made according to the new angiographic classification of Takayasu's arteritis, Takyasu conference 1994. Percutaneous transluminal angioplasty with stenting was performed on the thoracic and abdominal aorta. After the interventional procedures, the upper extremity blood pressure improved from 162/101 mmHg to 132/85 mmHg, respectively. She has been free of claudication and there have been no cardiac events during 2-yr of clinical follow-up.

Endomyocardial Biopsy: One Center's Report About Its Role

BACKGROUND AND OBJECTIVES: Cardiomyopathy is a common cause of heart failure, yet it is sometimes difficult to determine its exact etiology. Endomyocardial biopsy (EMBx) has been considered to be one of the important diagnostic modalities for unexplained cardiomyopathy. The aim of this study was to analyze the diagnostic value of EMBx. SUBJECTS AND METHODS: 30 patients (M : F=26 : 4, mean age: 41+/-11 yrs) who underwent EMBx since 1992 at St. Mary's hospital were enrolled. The patients were classified into 4 groups by their clinical manifestations as follows: Group I: 11 patients with left ventricular hypertrophy (LVH) of an unknown etiology and suspicious of having infiltrative disease on their non-invasive tests, Group II: 15 patients with heart failure of an unknown etiology and rapid progression, Group III: 2 patients with heart failure and peripheral eosinophilia, Group IV: 2 patients with suspicious arrhythmogenic right ventricular dysplasia and cardiac mass. RESULTS: EMBx confirmed the diagnosis in 8 of 30 cases (26.7%). In Group I, 3 patients were confirmed to have amyloidosis (27.3%). In Group II, 2 patients were diagnosed as having lymphocytic myocarditis (13.3%). In Group III, all of 2 patients (100%) were diagnosed as eosinophilic myocarditis. In Group IV, 1 patient was confirmed to have cardiac metastasis from esophageal cancer. The diagnostic rate was higher for Group III than for Group II (p=0.007). There were no complications related with EMBx. CONCLUSION: EMBx may be a useful tool to confirm the causes of cardiomyopathy in selected patients.

Erratum: The usefulness of ischemia modified albumin as an early ischemic marker to detect coronary artery disease in patients with chest pain presenting to the emergency department / 대한내과학회지

No abstract available.

Inhibition of Neointima Formation by Anti-Vascular Endothelial Growth Factor and Receptor-1 Peptides in a Balloon-Injured Rat Carotid Artery

BACKGROUND AND OBJECTIVES: Vascular endothelial growth factor (VEGF) is a potent endothelial cell-specific mitogen. This study was undertaken to test the hypothesis that the neointima hyperplasia induced by a balloon injury is inhibited by blocking VEGF and VEGF receptor-1 (VEGFR-1) with anti-VEGF peptides. Materials and Methods: Anti-VEGF RRKRRR peptide (dRK6) and anti-VEGFR-1 peptide (anti-flt-1) were synthesized at Pohang University of Science and Technology, Korea. Male Sprague-Dawley rats, weighing 300-350 g, were subcutaneously injected 0.5 mg/kg of dRK6 or 0.5 mg/kg of anti-flt-1, dissolved in phosphate buffer solution, 2 days before induction of a carotid balloon-injury, and then daily in the same manner post carotid balloon injury for 2 weeks. RESULTS: Neointima formation was suppressed in both the dRK6 and anti-flt-1 groups compared to that in the untreated controls at 2 weeks post carotid balloon-injury (neointimal area; control group 0.44+/-0.09 mm2, dRK6 group 0.25+/-0.05 mm2, anti-flt-1 group 0.19+/-0.05 mm2, p<0.01). Anti-flt-1 peptide and dRK6 reduced the numbers of proliferative bromodeoxyuridine-labeled cells in the neointima (control group 16.4+/-10.6%, dRK6 group 3.7+/-2.1%, anti-flt-1 group 5.9+/-3.4%, p<0.05). In addition, an inflammatory response, as determined by monocyte chemoattractant protein-1 and interleukin-6 upregulation, which was evident in the controls, was inhibited by both dRK6 and anti-flt-1. CONCLUSION: This study suggests anti-vascular endothelial growth factor peptides can reduce the inflammation and neointima formation in balloon injured rat carotid arteries.

Clinical features and prognostic factors in Korean patients hospitalized for coronary artery disease (Catholic Heart Care Network Study) / 대한내과학회지

BACKGROUND: Coronary artery disease (CAD) has recently become one of the major causes of mortality and morbidity in Korea. However, not much epidemiologic and demographic data has yet been reported. The purpose of this study was to investigate the clinical features as well as the prognostic factors of patients with CAD. METHODS: We prospectively enrolled 1,665 consecutive patients with CAD who had been admitted to the Catholic University Hospitals from December 1999 to April 2003. RESULTS: Acute myocardial infarction (AMI) was the most common cause of admission (n=715, 42.9%). Dyslipidemia, hypertension and smoking were the most common risk factors. More than 70% of the patients who underwent percutaneous coronary intervention (PCI) received stent implantation. A total of 965 (612 males) patients were followed at least for 6 months (the mean follow-up duration was 23.8+/-12.2 months). The incidence rates of major adverse cardiac events (MACE: cardiac death, acute myocardial infarction, target vessel revascularization) and cardiac death were 15.1% (n=146) and 2.2% (n=21), respectively. There was no difference in overall survival between the patients treated with medical therapy and those treated with PCI. By Cox regression analysis, the independent prognostic factors for MACE were PCI (95% CI: 1.75-4.85; p<0.01) and multivessel disease (95% CI: 1.03-2.04; p<0.05), and the independent prognostic factors for cardiac death were medical therapy (95% CI: 1.08-14.41; p<0.05) and old age (95% CI: 1.13-16.13; p<0.05). CONCLUSIONS: There was no difference in overall survival between the patients treated with medical therapy and those treated with PCI. However, PCI was superior to medical therapy for preventing death of the patients with acute coronary syndrome.

The usefulness of ischemia modified albumin as an early ischemic marker to detect coronary artery disease in patients with chest pain presenting to the emergency department / 대한내과학회지

BACKGROUND: A diagnosis of coronary artery disease (CAD) in the early phase of acute chest pain is often difficult in an emergency department (ED) due to the lower sensitive ECG and delayed expression of the cardiac necrosis markers. Ischemia modified albumin (IMA) has recently been reported to be an early sensitive biochemical marker of ischemia. The aim of this study was to evaluate the diagnostic value of IMA in patients with suspected CAD and less sensitive ECG/delayed cardiac necrosis markers. METHODS: 100 consecutive patients (mean age: 5413 years, male: 66%) presenting to the ED with suspected CAD and chest pain within 6 hours of chest pain were enrolled in this study. An ECG check and blood sampling for IMA and CK-MB, cardiac troponin-T (TnT) were done within 1 hour at the ED. The diagnosis of CAD was based upon the clinical findings, results of serial ECG/TnT and coronary angiography. The ideal cutoff value of IMA for CAD was calculated by the Receiver Operator Characteristic (ROC) curve analysis. RESULTS: CAD including acute coronary syndrome was diagnosed in 69/100 (69%). The optimum diagnostic cutoff point for the IMA levels in these study populations was found by ROC analysis to be 99.5 U/mL. The ROC curve area for the IMA test was 0.901 (95% confidential interval, 0.840-0.961, p=0.001). The IMA levels >99.5 U/mL demonstrated a sensitivity of 86%, specificity of 81%, positive predictive value of 90% and negative predictive value of 74% for the diagnosis of CAD. The combination of IMA-ECG-CKMB/TnT increased the sensitivity for detecting ischemia to 94%, with a negative predictive value of 85%. IMA is a highly sensitive with a high negative predictive value, and might improve the utility of standard biomarkers for CAD. CONCLUSIONS: IMA might be a useful ischemic marker of coronary artery disease in patients presenting within 6 hours after the onset of chest pain.

A Case of Patent Ductus Arteriosus Associated with Pulmonary Valve Endocarditis

Isolated infective endocarditis in the native pulmonary valve is unusual in non-intravenous drug user. Intravenous drug abuse, alcoholism, sepsis, catheter related infections and congenital heart diseases account for the majority of predisposing factors. We report a case of patent ductus arteriosus complicating infective endocarditis involving pulmonary valve. A 24-year-old female was admitted with fever of unknown origin Physical examination revealed continuous murmur at left 2nd intercostals space. Transthoracic and transesophageal echocardiography was performed and patent ductus arteriosus and vegetation at the pulmonary valve were noted. Chest CT scan revealed multiple patch infiltrate suggestive of septic emboli. After 4 weeks of antibiotic treatment, she had no clinical signs of fever, and blood culture be negative. Percutaneous trans-catheter closure of patent ductus arteriosus was done after 2 months.

A Case of Patent Ductus Arteriosus Associated with Pulmonary Valve Endocarditis

Isolated infective endocarditis in the native pulmonary valve is unusual in non-intravenous drug user. Intravenous drug abuse, alcoholism, sepsis, catheter related infections and congenital heart diseases account for the majority of predisposing factors. We report a case of patent ductus arteriosus complicating infective endocarditis involving pulmonary valve. A 24-year-old female was admitted with fever of unknown origin Physical examination revealed continuous murmur at left 2nd intercostals space. Transthoracic and transesophageal echocardiography was performed and patent ductus arteriosus and vegetation at the pulmonary valve were noted. Chest CT scan revealed multiple patch infiltrate suggestive of septic emboli. After 4 weeks of antibiotic treatment, she had no clinical signs of fever, and blood culture be negative. Percutaneous trans-catheter closure of patent ductus arteriosus was done after 2 months.

A Case of Intramural Hematoma Coexisting with Autosomal Dominant Polycystic Kidney Disease and Intracranial Aneurysm

Autosomal dominant polycystic kidney disease(ADPKD) is one of the most common hereditary diseases, and frequently has well defined extrarenal manifestations. Among the fatal vascular complications associated with ADPKD, ruptured intracerebral aneurysm and ruptured abdominal aortic aneurysm are widely known. Intramural hematoma(IMH) is a rare but potentially disastrous complication, and clinicians should always consider this when dealing with patients with ADPKD who present with acute dyspnea or chest pain. We report a case of a 67-year-old woman with the IMH as a fatal complication of ADPKD and intracranial aneurysm.

The Prediction of High Echogenicity of Intimal Area in Carotid Artery for the Plaque Burden of Culprit Lesion in Coronary Artery Disease

BACKGROUND AND OBJECTIVES: The intima-media thickness (IMT) of the common carotid artery has been widely used as a good index of atherosclerosis. The aim of this study was to test the correlation between the thickness of the high echogenicity intimal area (HELIT) on carotid ultrasound and the plaque burden of the culprit lesion on coronary intravascular ultrasound (IVUS). SUBJECTS AND METHODS: In 33 patients (M:F=20:13, mean age 63+/-8 yrs) that underwent coronary angiogram, the HELIT and IMT from carotid ultrasound were compared with the plaque burden of the culprit vessel on IVUS. The high echogenic layer of the intimal area (HELIA) on carotid ultrasound was defined as a thickened echogenic superficial layer at the far wall of the common carotid artery using 15 MHz linear array transducer. The plaque burden was defined as the maximal percent plaque area of the culprit lesion on IVUS. The HELIT and IMT ration was defined as the percent ratio of HELIT on IMT. RESULTS: The mean HELIT, carotid IMT, ratio of HELIT/IMT and maximal percent plaque area of the culprit lesion were 0.27+/-0.03 mm, 0.85+/-0.22 mm, 0.33+/-0.07 and 68.43+/-11%, respectively. The HELIT was closely related to the maximal percent plaque area on IVUS (r=0.34, p<0.05), but not to the other IVUS parameters or risk factors of CAD. CONCLUSION: Our data suggest that the high echogenic layer of the intimal area on carotid ultrasound is predictive of the plaque burden in the culprit vessel.

Echocardiographic Characteristics Related to Chronic Iron Overload in Patient with Aplastic Anemia

BACKGROUND AND OBJECTIVES: In patients with aplastic anemia, chronic iron overload due to multiple blood transfusions, leads to secondary hemochromatosis. Cardiac involvement in hemochromatosis is the leading cause of death. The goal of this study was to find the echocardiographic characteristics of patients with aplastic anemia and chronic iron overload. SUBJECTS AND METHODS: Echocardiography was performed on 33 patients with aplastic anemia (age 33+/-10, M:F=14:19) and 15 controls (age 34+/-8, M:F=6:9). The regions of interest on digitalized 2-D images of the papillary muscle (PM) in the parasternal short-axis view and the interventricular septum (IVS) in the apical 4-chamber view were analyzed using histograms, which quantified the echoreflectiveness (256 gray scales; black=0, white=255) of the myocardium. The echocardiographic parameters of each group were compared, including wall thickness, chamber dimensions, systolic, diastolic function indexes and echoreflectiveness. The aplastic anemic patients were divided into two groups (22 with serum ferritin level> or =2,000 microgram/L vs. 11 with<2,000 microgram/L) and then compared. RESULTS: The right ventricular (RV) wall was thicker in the patients than the controls (4.1+/-1.2 mm vs. 2.6+/-0.5 mm, p<0.01). In the patients, the echoreflectiveness of the PM was typically higher than in the controls (gray scale, 173.9+/-40.9 vs. 80.72+/-34.1, p<0.01), with IVS showing higher reflectivity, but this was not statistically significant (80.4+/-16.6 vs. 75.2+/-13.7, p=0.41). Patients with a ferritin level (2,000 microgram/L had a thicker RV wall (4.4+/-1.2 mm vs. 3.3+/-0.6 mm, p=0.01) and larger left atrium (LA) dimension (38.1+/-1.4 mm vs. 32.2+/-1.9 mm, p=0.02) than those with a ferritin level<2,000 microgram/L. No considerable difference was found between the echoreflectiveness of each group. CONCLUSION: The echocardiographic findings, such as high echoreflectiveness in the PM, RV wall hypertrophy and LA dilation, might be characteristics suggestive of early myocardial changes due to chronic iron overload as a result of multiple transfusions.

Utilization Pattern of Drug-Eluting Stents and Prognosis of Patients Who Underwent Drug-Eluting Stenting Compared with Bare Metal Stenting in the Real World

BACKGROUND AND OBJECTIVES: Currently, the drug-eluting stent (DES) has been widely used because of its excellent clinical outcome. We compared the utilization patterns and clinical outcomes between the DES and the bare metal stent (BMS) in the real world. SUBJECTS AND METHODS: We retrospectively reviewed the stent registry at the Catholic Medical Center between January 2002 and October 2004. There were 1120 patients treated with DES (n=1837) who were compared to 910 patients who received BMS implantation (n=1238). RESULTS: Patients with de novo lesions in the DES group more frequently had multivessel disease and received a greater number of stents than those in BMS group (p<0.001). The mean diameter of inserted stents was smaller in the DES group (p<0.001). The follow-up rate for clinical and angiographic evaluations at 6 months after stenting was 91% and 65% (n=592) in the BMS group and 90% and 74% (n=829) in the DES group, respectively. The rate of major adverse cardiac events (death, nonfatal myocardial infarction, or target vessel revascularization) at 6 months was 7.3% in the DES group and 17.5% in the BMS group (p<0.001). The rates of target vessel revascularization in the DES group and in the BMS group were 4.2% and 12.9%, respectively (p<0.001). CONCLUSION: The patients in the DES group had longer length, smaller diameter and higher number of placed stents, compared to the BMS group. The rates of revascularization and major adverse cardiac events in the DES group were lower than those in the BMS group.

Association between the Serum Osteoprotegerin Level and Target Lesion Calcium in Coronary Artery Disease

BACKGROUND AND OBJECTIVES: Osteoprotegerin (OPG) is a decoy receptor for receptor nuclear factor-kB ligand (RANKL). We sought to evaluate the association between the serum OPG level and the target lesion calcium (TLC) in those patients suffering with coronary artery disease (CAD). SUBJECTS AND METHODS: We assayed the serum OPG levels in 65 CAD patients (mean age: 62+/-10 yrs, M : F=46 : 19) with using enzyme immunoassay, and these patient underwent intravascular ultrasound (IVUS) examinations of their target lesions. The degree of TLC was estimated by the maximum arc of calcium and also the calcified plaque surface area that was calculated from the serial cross-section IVUS images. RESULTS: The median serum OPG levels were greater in the subjects with TLC than in the subjects without TLC (1.36 vs 0.95 ng/mL, respectively, p<0.05). Significant correlation was noted between the serum OPG levels and the maximum arc of calcium (r=0.274, p=0.027). The median serum OPG levels were significantly increased more in the subjects who had a maximum arc of calcium ranging from 90 to 180 degrees than in those subjects who had a maximum arc of calcium less than 90 degrees (1.63 vs 1.14 ng/mL, respectively, p<0.05) and the median serum OPG levels were also increased more in the subjects who fell within the second tertile of the calcified plaque surface area than that in those subjects who fell within the first and third tertile (0.96, 1.53, 1.40 ng/mL for the first, second, third tertile, respectively, p<0.05). On the stepwise multivariate logistic regression analysis, the serum OPG level remained a risk factor for TLC after adjustment was made for the other risk factors such as age, diabetes mellitus, HbA1C and a smoking history (p=0.019, odds ratio 5.208 [95% confidence interval: 1.308-20.744]). CONCLUSION: In patients with CAD, an increased serum OPG level is associated with target lesion calcification.

Hemodynamic Effects of Simulated Ventricular Tachycardia and Supraventricular Tachycardia in Dogs

BACKGROUND AND OBJECTIVES: Tachycardias have various clinical features according to the heart rate, the left ventricular systolic function, the site of origin and the mechanisms of the tachycardias. The primary purpose of this study was to evaluate the role of the origin site and cycle length on the ventricular tachycardia (VT) hemodynamics. Our secondary purpose was to explore the possible hemodynamic differences between the two common supraventricular tachycardias (SVT). MATERIALS AND METHODS: VT was simulated in 18 dogs that had there chests opened by using ventricular pacing (VP) at 3 different sites: the left ventricular apex (LVA), the right ventricular outflow tract (RVOT), and the right ventricular apex (RVA). The mean arterial pressure (MAP), the mean left atrial pressure (MLAP) and the mean pulmonary artery pressure (MPAP) were monitored during VP. To simulate SVT, the right atrial appendage and the right ventricular basal septum were stimulated at different cycle lengths with different ventriculo-atrial (VA) time intervals in another 11 dogs that had their chests opened. The arterial pressure, the pulmonary capillary wedge pressure and the cardiac output was observed during simulated atrial tachycardia (Group I), AVRT (Group II) and AVNRT (Group III). RESULTS: In the VT study, at the same pacing site as of the VP, the MAP was significantly decreased with the VP, and the deltaMAP was significantly increased as the length of the VP cycle shortened. At the same pacing cycle length of the VP, the deltaMAP was significantly greater at the RVA or RVOT than at the LVA. At the same pacing site of the VP, the MLAP and the deltaMLAP were significantly increased as the VP cycle length shortened. In the SVT study, MAP was highest in Group I and it decreased with the decreasing VA interval, but this was not significant. The systolic arterial pressure was significantly higher in Group II than in Group III. The CO was higher in Group I than in the other two groups, with a significant difference, and the CO decreased with shortening of the VA interval, but this was not significant. CONCLUSION: The above results suggest that in addition to the tachycardia rate, the origin site could be an independent factor of the VT hemodynamics. Episodes of AVRT and AVNRT may have a different hemodynamic impact that probably originates from the different timing of the ventricular and atrial contraction.

Predictability of the Left Ventricular Systolic and Diastolic Function according to the QRS Duration for Left Bundle Branch Block Patients

BACKGROUND AND OBJECTIVES: Left bundle branch block (LBBB) is an ECG finding that suggests a poor prognosis for patients suffering with cardiovascular disease. The aim of this study was to elucidate the relation between the QRS duration and the left ventricular function in the patients with LBBB. SUBJECTS AND METHODS: 95 patients (M : F=35 : 60, mean age: 69+/-13 yrs) with LBBB observed on ECG were recruited for this study. The relations among the QRS duration, the demographic.clinical findings and the conventional echocardiographic findings, including the LV systolic and diastolic function, were analyzed for these subjects. RESULTS: The QRS duration was closely related to the LV ejection fraction (r=-0.613, p or =158 msec showed a sensitivity of 73% and a specificity of 77% for predicting a LV EF <35%. CONCLUSION: The QRS duration is an important predictor that reflects the disease progression in patients with LBBB. Therefore, the QRS duration should be closely monitored in symptomatic patients with LBBB.

Chlamydia Pneumoniae Infection Initiates the Development of Atherosclerosis in OLETF and LETO Rats: The Role of Platelet-derived Growth Factor-B

BACKGROUND AND OBJECTIVES: Chlamydia pneumoniae (CP) has been linked with atherosclerosis. While several studies have shown that CP contributes to the acceleration of atherosclerotic lesions, any studies on the initiation of atherosclerosis are sparse. The present study investigated whether CP infection could initiate atherosclerotic lesions in rats that are known to be resistant to atherosclerosis; further, we investigated if these lesions do form, then how does the CP participate in this and develop of atherosclerosis in these rats. MATERIALS AND METHODS: Thirty 11-week-old Otsuka Long-Evans Tokushima Fatty (OLETF) rats, thirty type 2 diabetic rats and thirty age-matched Long-Evans Tokushima Fatty (LETO) rats that were maintained on a high-cholesterol diet were either mock-inoculated or inoculated intranasally 3 times at 11, 13 and 15 weeks of age. The serum levels of the lipid profiles, plasminogen activator inhibitor-1 (PAI-1), monocyte chemoattractant protein-1 (MCP-1) and C-reactive protein (CRP) were measured by performing ELISA at 24 weeks and 40 weeks of age. The atherosclerotic lesion areas were analyzed, and immunohistochemical staining using chlamydia genus-specific monoclonal antibody and PDGF-B was performed in the ascending aorta at 40 weeks of age. RESULTS: Immunohistochemical staining with using specific monoclonal antibody demonstrated CP infection in the vessel walls. The serum PAI-1 level of the OLETF rats was higher than that of the LETO rats (p<0.05) regardless of the state of the CP infection, but there were no differences in the serum MCP-1 and CRP levels between the OLETF rats and the LETO rats. While no atherosclerotic lesion was observed in the mock-infected LETO rats, early-to-advanced atherosclerotic lesions were found in the other rat groups. CP-infected OLETF rats showed more advanced atherosclerotic lesions and greater mean lesion areas than the other rat groups (LT-N, 0 mm2; LETO-CP, 3.29+/-1.23 mm2; OT-N, 4.91+/-2.11 mm2; OT-CP, 9.20+/-4.62 mm2)(p<0.05). The characteristics of the atherosclerotic lesions in the rats were intimal thickening that was mainly composed of smooth muscle cells. The atherosclerotic lesion area positively correlated with the presence and the extent of PDGF-B staining in the aortic wall (p<0.01). CONCLUSION: Chronic infection of CP in the vessel walls initiated the development of atherosclerosis in the LETO rats and it accelerated the atherosclerosis in the OLETF rats. CP-induced smooth muscle proliferation and the resultant intimal thickening may be mediated by PDGF-B in these atherosclerotic lesions.

Prospective, Randomized, Preliminary Clinical Trial with Low-Molecular-Weight Heparin or Unfractionated Heparin as Periprocedural Anticoagulant during Elective Percutaneous Coronary Intervention

BACKGROUND AND OBJECTIVES: LMWH as a periprocedural anticoagulant during PCI has not yet been extensively studied. The aim of this study is to compare the clinical outcomes of enoxaparin to those of unfractionated heparin (UH) during elective PCI. SUBJECTS AND METHODS: The eligible patients were randomized 1:1 into two treatment arms, either a single IV bolus of enoxaparin (75 IU/kg) or UH (100 IU/kg). The patients who had received any anticoagulants at therapeutic doses were excluded in this study. Data on patient characteristics, angiographic complications, laboratory variables and the in-hospital and 1-month clinical outcomes were compared between the two groups. RESULTS: Of the 139 patients enrolled in this study, 68 received enoxaparin and 71 received UH. The patients' demographic and angiographic characteristics (gender, weight, creatinine and the PCI target vessel) were not different except for age between the groups. Multi-vessel angioplasty was performed in 59 (42.4%) patients. At least one stent was implanted in 130 (93.5%) patients. The sheath was removed immediately after PCI, except for one case, and then a collagen plug was applied in all the cases. There were no significant differences in angiographic complications like no reflow, thrombus at the treated lesion site, occlusion of collateral branches, distal embolism, dissection, coronary rupture or abrupt closure. Cardiac markers including CK (6 [8.8%] in the LMWH group vs 8 [11.3%] in the UH group), CK-MB (6 [8.8%] vs 8 [11.3%], respectively), and troponin-I (6 [8.8%] vs 10 [14.1%], respectively) were slightly increased after PCI compared to the last value obtained before the procedure in both groups, but the differences were not statistically significant. One patient in the enoxaparin arm and 2 patients in the UH arm developed NSTEMI during their admission. Four patients from the UH arm and 3 from the enoxaparin arm experienced hematoma at the puncture site. After discharge, no other events were reported at the 1-month follow-up. CONCLUSION: The use of enoxaparin (75 IU/kg) during elective PCI was effective and safe as using UH. Enoxaparin could be used like UH as a periprocedural anticoagulant in the elective PCI setting.

Prospective, Randomized, Preliminary Clinical Trial with Low-Molecular-Weight Heparin or Unfractionated Heparin as Periprocedural Anticoagulant during Elective Percutaneous Coronary Intervention

BACKGROUND AND OBJECTIVES: LMWH as a periprocedural anticoagulant during PCI has not yet been extensively studied. The aim of this study is to compare the clinical outcomes of enoxaparin to those of unfractionated heparin (UH) during elective PCI. SUBJECTS AND METHODS: The eligible patients were randomized 1:1 into two treatment arms, either a single IV bolus of enoxaparin (75 IU/kg) or UH (100 IU/kg). The patients who had received any anticoagulants at therapeutic doses were excluded in this study. Data on patient characteristics, angiographic complications, laboratory variables and the in-hospital and 1-month clinical outcomes were compared between the two groups. RESULTS: Of the 139 patients enrolled in this study, 68 received enoxaparin and 71 received UH. The patients' demographic and angiographic characteristics (gender, weight, creatinine and the PCI target vessel) were not different except for age between the groups. Multi-vessel angioplasty was performed in 59 (42.4%) patients. At least one stent was implanted in 130 (93.5%) patients. The sheath was removed immediately after PCI, except for one case, and then a collagen plug was applied in all the cases. There were no significant differences in angiographic complications like no reflow, thrombus at the treated lesion site, occlusion of collateral branches, distal embolism, dissection, coronary rupture or abrupt closure. Cardiac markers including CK (6 [8.8%] in the LMWH group vs 8 [11.3%] in the UH group), CK-MB (6 [8.8%] vs 8 [11.3%], respectively), and troponin-I (6 [8.8%] vs 10 [14.1%], respectively) were slightly increased after PCI compared to the last value obtained before the procedure in both groups, but the differences were not statistically significant. One patient in the enoxaparin arm and 2 patients in the UH arm developed NSTEMI during their admission. Four patients from the UH arm and 3 from the enoxaparin arm experienced hematoma at the puncture site. After discharge, no other events were reported at the 1-month follow-up. CONCLUSION: The use of enoxaparin (75 IU/kg) during elective PCI was effective and safe as using UH. Enoxaparin could be used like UH as a periprocedural anticoagulant in the elective PCI setting.