Yılmaz Özbay

The effect of long-term clopidogrel use on neointimal formation after percutaneous coronary intervention.

ObjectiveThe purpose of this study was to evaluate the long term effect of clopidogrel-based antiplatelet therapy on neointimal formation. MethodsThis study comprised 78 patients with typical stable angina pectoris or documented myocardial ischaemia, and with only one angiographic lesion in one native coronary artery undergoing successful stent implantation without predilatation with C-reactive protein levels ≤5 mg/l at 72 h after the procedure. All patients received dual antiplatelet therapy with 75 mg/day clopidogrel and 300 mg/day aspirin for four weeks. Clopidogrel was switched to isochronous placebo in half of the patients (n=39) at the end of the fourth week. This allocation was maintained for 20 weeks, and at week 24 of the study, coronary angiography and intravascular ultrasound imaging were performed again in all cases in order to evaluate the changes that had occurred in the in-stent neointimal formation; rates of restenosis were also recorded ResultsAt the end of the follow-up period, angiographic stenosis diameter and restenosis rates were smaller in the clopidogrel group than in the placebo group (23.3% versus 35.6%, p=0.05 and 5.12% versus 10.25%; p=0.03 respectively); the intravascular ultrasonographic neointimal cross sectional area was also smaller in the clopidogrel group (3.6±2.7 mm2 versus 5.2±2.5 mm2, p=0.03). ConclusionsLong-term clopidogrel administration significantly reduced neointimal formation at the stent site as well as reducing major clinical events in patients who did not develop high-risk systemic inflammatory response after percutaneous coronary intervention.

The level of hs-CRP in coronary artery ectasia and its response to statin and angiotensin-converting enzyme inhibitor treatment.

Background/Aim. Coronary artery ectasia (CAE) was thought of as a variant of atherosclerosis. C-reactive protein (CRP) which is among the most sensitive markers of systemic inflammation, and elevation of systemic and local levels of this inflammatory marker which has been associated with an increased risk for cardiovascular disease in the obstructive coronary artery disease (O-CAD) are well known, but little was known in CAE. The anti-inflammatory effects of statins and the effect of angiotensin-converting enzyme (ACE) inhibitors on endothelial dysfunction are well established in atherosclerosis. The aim of the present study was to investigate CRP level and its response to statin and ACE inhibitor treatment in CAE. Materials and method. We measured serum hs-CRP level in 40 CAE (26 males, mean age: 56.32 ± 9 years) and 41 O-CAD (34 males, mean age: 57.19 ± 10 years) patients referred for elective coronary angiography at baseline and after 3-month statin and ACE inhibitor treatment. Results. Plasma hs-CRP levels were significantly higher in CAE group than O-CAD group at baseline (2.68 ± 66 mg/L versus 1, 64 ± 64, resp., P < .0001). Plasma hs-CRP levels significantly decreased from baseline 3 months later in the CE (from 2.68±0.66 mg/L to 1.2±0.53 mg/L, P < .0001) as well as in the O-CAD group (from 1.64±0.64 mg/L to 1.01±0.56 mg/L, P < .001). Conclusion. We think that hs-CRP measurement may be a good prognostic value in CAE patients as in stenotic ones. Further placebo-controlled studies are needed to evaluate the clinical significance of this decrease in hs-CRP.

Effects of tirofiban on acute systemic inflammatory response in elective percutaneous coronary interventions

SUMMARY Objective: In this study the effect of a specific glycoprotein IIb/IIIa inhibitor, tirofiban [which also has antiplatelet activity on acute systemic inflammatory responses (IR) during elective percutaneous coronary intervention (PCI)] was evaluated. Patients and methods: Patients with stable angina pectoris and similar baseline characteristics who angiographically had a single lesion in their coronary arteries with a PCI performed on that lesion were enrolled in the study. One group of patients (control group, n = 52) received 0.9% NaCl (15 mL/h for 24h) and the other group (tirofiban group, n = 55) had tirofiban (10|ig/kg bolus infusion in 3min and 0.15jj,g/kg/mir for 24h) in addition to stenting without pre-dilatation. The effect of interventional procedure on levels of cardiac troponin T (cTnT) and several parameters of acute IR (leukocytes, fibrinogen, C-reactive protein, interleukin-1, interleukin-6, interleukin-8 and tumor necrotizing factor-α) was assessed on blood samples obtained from all patients before PCI and at pre-specified time points after PCI. Results: During the follow-up after PCI, the number of patients becoming cTnT-positive (> 0.1 ng/mL) was greater in the control group [12 (23%) patients vs. 3 (5%) patients, p = 0.01]. However, both groups had changes (generally observed as elevations) in their levels of all inflammatory parameters during the study and C-reactive protein, interleukin-6 and tumor necrotizing factor-α levels were elevated significantly. Yet, no significant difference occurred between groups due to these changes in any phase of the study (p > 0.05). Conclusions: Based on the findings of this study, it was concluded that although tirofiban limits development of myocardial necrosis during elective PCI, it does not directly affect the acute systemic inflammatory responses.

[The relation of intima-media thickness with endothelial function and left ventricular mass index].

OBJECTIVE We aimed to investigate the relation of brachial artery intima-media thickness (IMT) with endothelial function and left ventricular mass (LVM). METHODS Fifty-four stage I-II hypertensive patients according to JNC VII who were not taking any medication and 27 age and sex-matched healthy controls were included to this cross-sectional observational study. IMT was measured by the same radiologist who was unaware of the patients clinical status by using high resolution ultrasound machine. Endothelial function was evaluated by flow mediated dilation (endothelium-dependent vasodilatation, FMD). LVM was calculated by using Devereux method. LVM index (LVMI) was obtained by dividing LVM to body surface area. Mann-Whitney U test was used to compare continuous variables, qualitative variables were compared by Chi-square test and the relations of parameters were evaluated by multiple linear regression analysis. RESULTS Both groups (hypertensive and control) were similar with respect to age, sex, left ventricular ejection fraction. IMT was significantly higher in hypertensive group (0.43+/-0.09 vs 0.33+/-0.06 mm; p<0.001). FMD values were also significantly different between hypertensive and control groups (4+/-4% vs 13+/-12%; p<0.001). LVMI was significantly different between hypertensive and control groups LVMI (124 +/- 5 vs 99+/-6 gr/m2, p=0.002). The correlation between IMT and FMD (r=0.260; p=0.026) and IMT and LVMI (r =0.348; p=0.004) were statistically significant. A correlation was found between IMT and LVMI independently of other variables (beta=105; p=0.004) when LVMI was accepted as dependent variable in multivariate linear regression analysis (R2=0.570, p<0.001). According to this finding, the 105 units increase in LVMI occurs when IMT increases by 1 mm. CONCLUSION Brachial artery IMT is related to endothelial function and LVM. According to these data, any negative changes of the IMT may reflect the similar negative changes in other parameters.

Efficacy of Clopidrogel on Reperfusion and High-Sensitivity C-Reactive Protein in Patients with Acute Myocardial Infarction

We investigated the effects of clopidogrel on reperfusion and inflammatory process in STEMI. A total of 175 STEMI patients with similar clinical characteristics were included to this study. One was the standard pharmacological reperfusion therapy group (group 1, n : 90), who received 300 mg aspirin, 70 U/kg bolus, and 12 U/kg/hr continuous infusion of unfractioned heparin and accelerated t-PA. Clopidogrel 450 mg loading and 75 mg/d thereafter was added to standard reperfusion therapy in the other group (group 2, n : 85). The ST-segment resolution, CK-MB, and high-sensitive CRP (hs-CRP) parameters were measured. Complete ST resolution was observed in 32 patients (36.8%) in group 1 and 53 patients (63.8%) in group 2 (P < .001). Also in the first 24 hours, the CK-MB levels of patients in group 1 were significantly higher than those of group 2 (P = .001). The hs-CRP values were greater in group 1 than group 2 at 48th hour (gruop 1: 9.4 ± 0.1 mg/L, group 2: 3.7 ± 1.4 mg/L; P = .000). We concluded that adding clopidogrel to standard treatment in STEMI patients provided early reperfusion and suppression of inflammatory response.

The Diagnostic Values of Brain Natriuretic Peptide and Cardiac Troponin I for Determining the Right Ventricle Dysfunction in Patients with Submassive Pulmonary Thromboembolism

Determinig the right ventricule dysfunction (RVD) in pulmonary thromboembolism (PTE) is very important for prognosis and treatment option. RVD is usually diagnosed by echocardiographic findings. Recent studies have suggested that the measurement of levels of serum levels of cardiac troponın I (cTnI) and brain natriuretic peptid (BNP) which cardiac biomarkers can define RVD. The aim of this study is evaluating the diagnostic value of BNP, cTnI serum levels for determining RVD in patients with submassive PTE. Fifty patients with definitive diagnosis of PTE is included in the study. For determining a probable RVD, echocardiography is applied to them. Serum BNP, cTnI levels were measured during admission. Fifty-two of the patients included in the study, RVD were detected with EKO. In 44% of the patients high levels of BNP and 10% of the patients high l cTnI were found respectively. High levels of BNP was found in %73 of patients with RVD (+) and in %12 of patients with RVD ( -). High levels of cTnI was found in %12 of patients with RVD (+) and in %8 of patients with RVD ( -). BNP levels were significantly high in patients with RVD (+) when compared with RVD ( -), and control group. When cTnI levels of groups are compared no significant difference was observed. In conlusion, it is suggested that high levels of BNP can be thought as a marker for RVD, patients who have high levels of BNP can be followed closely, and determined for thrombolitic therapy.

Direct stenting application in acute coronary syndromes

Although published reports about direct stenting in treating stable coronary artery disease have been increasing, the number of studies regarding direct stenting for acute coronary syndrome is limited. In this study, we report immediate and mid-term results of patients who underwent direct stenting for treating acute coronary syndrome. The average lesion length was 12.1 ± 3.3 mm. The preprocedure average minimum luminal diameter (MLD) was 0.67 ± 0.33 mm. Post-procedure average MLD was 3.19 ± 0.42 mm. In 35 of the 36 cases (97%), the stent delivery system crossed the lesion and was implanted successfully. In one case, an acute occlusion, which was treated by percutaneous transluminal coronary angioplasty (PTCA), occurred. The rate of procedure success was 94%. The amount of contrast media used was 88 ± 16 ml and duration of radiation exposure was 9 ± 2 min. Control angiography was performed in 28 out of 35 cases (80%). Seven patients who did not consent to coronary angiography were asymptomatic and had negative exercise tests. MLD was 2.66 ± 0.53 mm after a six month follow-up. The clinical and angiographic restenosis rates were 14% (5/35) and 18% (5/28), respectively. Three of the five cases of restenosis were treated by excimer laser coronary angioplasty (ELCA) and PTCA and the other two were treated with PTCA only. Target lesion revascularization rate was 14% (5/35). The rate of major adverse cardiac events (MACE) was 17% (6/35) after the six month follow-up period. Based on these results, we conclude that direct stenting for acute coronary syndrome is safe if the lesion is determined to be suitable.

A single center experience with the newly designed R Stent in small coronary vessels.

BACKGROUND: Over the past 10 years stents have been used more frequently for the treatment of de novo coronary artery stenosis. Initally these devices were used primarily in coronary arteries with diameters ranging from 3.0 to 4.0 mm. Traditionally, coronary arteries less than 3.0 mm in diameter were treated with only balloon angioplasty, due to the unavailablity of flexible, low profile, small diameter stents. In the past three years, many stents have been designed to be implanted in small coronary arteries. OBJECTIVE: The objective of this study was to evaluate the safety and feasiblity of the R Stent in patients with coronary lesions located in coronary arteries with a reference diameter 2.5-3.0 mm. METHODS AND RESULTS: Between November 1998 and September 1999, 32 patients with stable (37%) and unstable (63%) angina treated with the R Stent were included in this study. The treated lesions were in the right coronary artery (RCA) ( n = 13), left cirumflex coronary artery (LCX) ( n = 10), and left anterior descending coronary artery (LAD) ( n = 9). Of these lesions thirteen were anatomically complex. Stent deployment was successful in 97% with one crossing failure in a patient with a vessel tortuosity of greater than 75 degrees of the circumflex artery. No post-procedual major adverse cardiac and cerebrovascular event (MACCE) occurred within 30 days of stent implantation. After the procedure, patients were scheduled for a two-week telephone follow-up and a one-month clinical evaluation. At 30 days, only one patient (3%) experienced the recurrence of angina Canadian cardiovascular society classification ((CCS) Class 2). All other patients were event and angina free. CONCLUSION: This first clinical experience in patients with small vessel disease shows that the use of the R stent is safe and feasible with low rates of acute stent thrombosis.