Inflammation and restenosis after percutaneous coronary interventions

The role of inflammation in the development of restenosis afterpercutaneous coronary interventions has been investigated inseveral studies. There is an interaction of inflammatory activationand vascular wall response to injury leading to intimal hyperplasia.Percutaneous interventions trigger inflammatory reactions leadingto the development of intimal hyperplasia. This reaction iseven more prominent in atheromatic plaques in which inflammatorycells have already been activated. In the clinical setting thereare several methods for the recognition of the inflammatoryactivation. In this article we review the data for the roleof inflammatory process in restenosis and the significance ofidentifying the inflamed lesions prior to the intervention.Moreover, the therapeutic implications for the inhibition ofinflammatory activation are mentioned.     

No influence of hemochromatosis-related gene mutations on restenosis rate in a retrospective study of 137 patients after coronary stent implantation

BACKGROUND: Recent publications have shown an increased risk of coronary artery disease and myocardial infarction in patients with alteration of the hemochromatosis-related gene (HFE gene). The HFE gene mutation is associated with elevated iron uptake and serum iron overloading. Iron plays an important role in promoting the oxidation of LDL cholesterol. The iron deposition in the endothelium and in the media is closely associated with the progression of atherosclerosis. However, it is unclear whether the mutation of the HFE gene also influences the rate of restenosis after coronary stent implantation. METHODS: In a retrospective analysis, 137 patients (pts.) who underwent elective coronary stent implantation were angiographically reevaluated after six months. All patients were part of the OPTICUS-study population which investigated optimized stent implantation guided by intravascular ultrasound. Computerized quantitative analysis was performed in all procedures in a double-blinded fashion. At six-month follow-up, DNA fragments containing the substitution of tyrosine for cytosine at codon 282 were amplified by PCR. The results were analyzed by polyacrylamide gel electrophoresis. Statistical analysis was performed by multivariate linear regression. RESULTS: According to the HFE gene polymorphism we formed two subgroups: 129 pts. (94%) did not show changes in HFE gene (NH), 8 pts. (6%) were heterozygous for HFE Cys282Tyr (H). The groups did not differ in age, gender, extent of coronary artery disease, initial degree and length of stenosis and all patients underwent re-angiography. At six-month follow-up the average luminal narrowing in the stented vessel was 36.2 &#45 20.3% in the NH group compared with 27.8 &#45 20.0% in the H group which was statistically not significant (n. s.). The minimal luminal diameter was 1.9 &#45 0.71 mm in the NH group and 2.2 &#45 0.66 mm in the H group respectively (n. s.). 33 pts (26%) in the NH group versus 2 pts (25%) in the H group had &#83 50% diameter narrowing at follow-up (n. s.). The odds ratio of stent restenosis in H patients was 0.932. CONCLUSIONS: The authors did not find any association between restenosis rate and HFE gene alteration and therefore, we conclude that the polymorphism of the HFE gene is not a risk factor for restenosis after coronary stent implantation.     

单核细胞趋化蛋白-1基因多态性与冠状动脉介入治疗后再狭窄的相关性研究

目的 探讨单核细胞趋化蛋白-1(MCP-1)启动子区-2518A/G基因多态性与冠状动脉(冠脉)粥样硬化病变进程及经皮冠脉腔内成形术(PCI)后再狭窄的相关性.方法 对276例接受PCI并进行冠脉造影随访的患者,采用PCR-RFLP方法进行MCP-1 -2518A/G多态性检测;按冠脉造影结果分为再狭窄组(113例)和无再狭窄组(163例),判定冠脉血管病变及再狭窄与MCP-1 -2518A/G多态性的相关性.结果 MCP-1 -2518A/G基因型频率为:AA纯合子21.0%,GG纯合子34.1%,AG杂合子44.9%,3种基因型血管病变支数和血管平均狭窄程度,差异均无统计学意义(P＞0.05).再狭窄组中AA、AG和GG基因型频率分别为23.9%、40.7%和35.4%,无再狭窄组分别为19.0%、47.9%和33.1%,差异无统计学意义(P=0.446).再狭窄组中-2518A和G等位基因频率分别为44.2%和55.8%,无再狭窄组分别为42.9%和57.1%,差异无统计学意义(P=0.761).结论 冠脉粥样硬化进程及PCI术后再狭窄可能与MCP-1 -2518A/G基因多态性无相关性.     

Gender and restenosis after coronary artery stenting.

AIMS: To examine the impact of sex on restenosis in a large cohort of consecutive patients undergoing coronary stenting and systematic angiographic and clinical follow-up. METHODS AND RESULTS: The study includes a cohort of 4374 consecutive patients (1025 women and 3349 men), undergoing coronary stenting for stable or unstable angina. Follow-up angiography at 6 months was performed in 80% of patients. Clinical events were assessed for a period of 1 year after the procedure. Main end-points of the study were angiographic and clinical restenosis at follow-up. Compared to men, women were older, presented more often with diabetes, smaller vessel size and shorter lesions. Clinical restenosis (need for reintervention) was found in 14.8% of women and 17.5% of men (P=0.048). The incidence of angiographic restenosis was significantly lower in women then in men (28.9% vs 33.9%, respectively, P=0.01). After adjustment for other covariates, women presented a 23% reduction of the risk of restenosis: odds ratio 0.77 (95% confidence interval 0.63 to 0.93). While a small vessel size was a risk factor for restenosis in both sexes, the influence of diabetes on restenosis was mostly confined to women. CONCLUSION: Compared with men, women present a lower risk of restenosis after coronary stenting despite a more preponderant presence of two major risk factors for restenosis, diabetes and small vessel size. There are sex-based differences in predictive factors of restenosis with diabetes having a particularly strong impact in women.     

经皮冠状动脉腔内成形术及再狭窄对QT离散度的影响

目的观察经皮冠状动脉腔内成形术（ＰＴＣＡ）对ＱＴ离散度（ＱＴｄ）的影响及ＰＴＣＡ术后再狭窄时ＱＴｄ的变化。探讨ＱＴｄ在预测再狭窄中的意义。方法将３０例临床拟诊ＰＴＣＡ术后再狭窄的患者根据第二次冠状动脉造影（冠造）的结果分为再狭窄组（１９例）及非再狭窄组（１１例）。对两组患者第一次ＰＴＣＡ术前后、第二次ＰＴＣＡ（或冠造）术前后的同步１２导联心电图同时进行ＱＴｄ（ＱＴｄ＝最大ＱＴ间期－最小ＱＴ间期）及校正的ＱＴ离散度（ＱＴｃｄ）的测定。结果　两组患者第一次ＰＴＣＡ术后ＱＴｄ及ＱＴｃｄ均较术前显著减小（Ｐ＜０．００５）。再狭窄组第二次ＰＴＣＡ术前ＱＴｃｄ（７０．９±１７．１）ｍｓ又恢复至第一次ＰＴＣＡ术前（７３．５±１７．２）ｍｓ的水平,且显著大于（Ｐ＜０．００１）第一次ＰＴＣＡ术后（３５．２±８．９）ｍｓ及第二次ＰＴＣＡ术后（３４．５±９．３）ｍｓ的水平。非再狭窄组第二次冠造前ＱＴｃｄ（３０．７±８．５）ｍｓ与第一次ＰＴＣＡ术后（２９．３±８．１）ｍｓ比较无显著变化（Ｐ＞０．０５）,仍显著小于（Ｐ＜０．００５）第一次ＰＴＣＡ术前（６９．６±１２．７）ｍｓ。结论ＰＴＣＡ术可降低冠心病患者ＱＴ离散度,再狭窄时ＱＴ离     

Comparison of synchrotron radiation angiography with conventional angiography for the diagnosis of in-stent restenosis after percutaneous transluminal coronary angioplasty.

AIMS: Synchrotron radiation angiography (SRA) is a novel tool for minimally invasive coronary artery imaging. The method uses subtraction of two images produced at energies bracketing the iodine K-edge after intravenous infusion of iodinated contrast agent. We investigated the accuracy of SRA for detecting in-stent restenosis (ISR). METHODS AND RESULTS: We recruited 57 men, 4-6 months after successful PTCA. We visualized the right coronary artery (RCA) in 27 patients with 36 stented segments [12 segments with ISR>50% by quantitative coronary angiography (QCA)], and the left anterior descending artery (LAD) in 30 patients with 37 stented segments (10 ISR). SRA and QCA were performed within 2 days of each other. Two experienced observers unaware of QCA data evaluated the SRA results. Image quality was good or excellent in most patients. Global sensitivity was 64%, specificity was 95%, and positive and negative predictive values were approximately 85%. Inter-observer kappa concordance coefficient was 0.86. False negatives involved short eccentric lesions and superimposed segments, most frequently of the LAD. False positives occurred in intermediate stenoses slightly overestimated by SRA. CONCLUSION: In men, this minimally invasive approach, using small radiation doses, detects significant ISR in the RCA, but the LAD poses difficulties because of superimposition with others structures.     

细胞间黏附分子-1基因K469E多态性与冠状动脉支架置入后再狭窄相关性的初步探讨

目的　炎症反应是冠状动脉支架置入后再狭窄的重要因素 ,细胞间黏附分子 1(ICAM 1)是介导白细胞在血管内皮细胞表面紧密黏附的重要黏附分子。本研究的目的在于探索ICAM 1基因多态性与中国北方汉族人群中冠状动脉支架置入后再狭窄的相关性。方法　收集冠状动脉支架术后行冠状动脉造影随访的患者 12 4例 ,同时收集传统危险因素、手术相关因素信息。应用PCR RFLP方法确定ICAM 1K4 6 9E基因型。结果　入选的 12 4例患者中再狭窄者 72例 ,无再狭窄者 5 2例 ;12 4例中ICAM 1K4 6 9E基因型频率为 :KK纯合子 5 0 8% ,EE纯合子 7 3% ,EK杂合子 4 1 9%。再狭窄患者中KK纯合子和E等位基因携带基因型的频率分别为 5 8 3%、4 1 7% ;无再狭窄患者中二者的频率分别为 4 0 4 %、5 9 6 %。二者分布差异有显著性 (P =0 0 4 9)。调整混杂因素后显著性差异更为明显 ,KK纯合子OR值为 2 6 ,95 %可信区间为 1 2～ 5 8(P =0 0 18)。危险因素分层发现在肥胖 (体重指数≥ 2 7)、高脂血症患者KK纯合子的再狭窄危险更高 ,OR值分别为 9 3、3 7(P值均小于 0 0 5 )。结论　ICAM 14 6 9KK纯合子冠状动脉支架置入后再狭窄危险性较高 ,且在肥胖或高脂血症患者中作用更为显著。     

冠状动脉血管的口径对PTCA术后再狭窄的影响

经皮冠状动脉腔内成形术（PTCA）术后再狭窄仍然是目前的重要难题之一。本研究对303例PTCA成功者，测定正常冠状动脉管径和PTCA术后再狭窄管径，结合临床冠心病危险因子及与再狭窄相关连的病变形态因子的定量分析进行对比研究，采用Automatededgedetecting法测出术前正常冠状动脉管径（NCD）按NCD的大小分为三组，A组NCD＜25mm；B组2．5～3．0mm；C组≥3．0mm；同时分别测出A、B、C三组术前、术后PTCA部位的最小血管径（MVD．mm）以及PTCA术后3个月追踪造影时PTCA部位的MVD，采用Caliper法分别计算出PTCA前、后狭窄率、3个月后追踪时再狭窄率。结果显示，冠心病的危险因子、PTCA前偏心性病变、钙化病变及扩张后冠状动脉夹层在三组间未见显著差异，PTCA前NCD（mm）、MVD（mm）及PTCA术后MVD（mm）C组显著高于A组（P＜0．01），再狭窄率A组显著高于C组（P＜0．01）。我们认为正常冠状动脉径较细者，PTCA术后容易发生再狭窄，冠状动脉本身的粗细可以作为PTCA术后再狭窄的独立预测因子之一。     

Recruitable collateral blood flow index predicts coronary instent restenosis after percutaneous coronary intervention.

AIMS: Collateral flow may influence long-term results after percutaneous coronary intervention (PCI) because of haemodynamic forces compete with the antegrade flow through the dilated lesion. The aim of the study was to assess the influence of recruitable collateral blood flow on restenosis in patients undergoing PCI with bare metal stents and using optimal antithrombotic treatment. METHODS AND RESULTS: In 95 patients, 95 de novo lesions were treated with PCI and a bare metal stent. Fractional flow reserve (FFR) at maximum hyperaemia induced by intravenous adenosine was determined. The pressure-derived collateral flow index (CFI) was determined as (P(w)-P(cvp))/(P(a)-P(cvp)), where P(w) represents coronary wedge pressure, P(cvp) central venous pressure, and P(a) mean aortic blood pressure. Both were measured during transient coronary occlusion by a balloon inflation of 30 s. Pre-interventional FFR (0.65 +/- 0.20) correlated inversely with the CFI (0.18 +/- 0.11), r =- 0.356, P < 0.001. After 9 months, binary angiographic restenosis (>/=50% diameter stenosis) was seen in 29.1%. Compared to patients with poorly developed collaterals (CFI < 0.25), patients with well-developed collaterals (CFI >/= 0.25) had a lower pre-interventional FFR (0.50 +/- 0.14 vs. 0.72 +/- 0.18, P < 0.001), a higher CFI (0.33 +/- 0.08 vs. 0.13 +/- 0.07, P < 0.001), and a higher binary restenosis rate (54.2% vs. 19.4, P = 0.003). CFI*100 was an independent predictor of restenosis after 9 months (odds ratio 1.07, 95% CI 1.02-1.12, P = 0.016). CONCLUSION: Recruitable collateral blood flow measured during balloon inflation predicts angiographic instent restenosis in PCI patients treated with bare metal stents.     

Adiponectin incompletely prevent MCP-1-dependent restenosis after percutaneous coronary intervension in patients with coronary artery disease

Background Some factors play pathogenic roles in the development of restenosis after percutaneous coronary intervention (PCI). We measured and compared the ratio of elevated levels of monocytic chemotactic peptide-1 (MCP-1), regulated on activation normally T-cell expressed and secreted (RANTES), soluble (s) P-selectin, sE-selectin and adiponectin after PCI. Methods Plasma levels of chemokines and soluble markers were measured before and 30 days after PCI in 96 patients (69 males and 27 females, aged 63 ± 9 years) who underwent PCI and who had repeated angiograms at a 6-month follow-up. In addition, we carried out the basic study of the tissue factor expression on monocytic cell line (THP-1) by MCP-1. Results Restenosis occurred in 33 (34.4%) patients. A significant and time-dependent increase in MCP-1 was observed in the restenosis group. However, there were no significant differences in RANTES, sP-selectin, and sE-selectin levels with or without restenosis. Adiponectin levels in patients with coronary artery disease were significantly lower than levels in normal controls. However, adiponectin levels were no different at baseline between patients with or without restenosis. MCP-1 did not induce the expression of tissue factor on THP-1. However, the recombinant sCD40 ligand-induced expression of tissue factor on THP-1 was enhanced by the addition of MCP-1. Conclusion These findings suggest that restenosis development after PCI in patients with coronary artery disease may involve the participation of MCP-1 after PCI, and adiponectin incompletely prevent this MCP-1-dependent restenosis.     

The 5A6A polymorphism in the promoter of the stromelysin-1 (MMP3) gene as a risk factor for restenosis.

AIMS: Intracoronary ultrasound studies in humans show that chronic remodelling rather than neointimal hyperplasia is the mechanism of restenosis. Stent implantation limits this remodelling process and significantly reduces restenosis. MMP3 (Stromelysin-1), a member of the matrix metalloproteinase family may play a role in this remodelling. We used a functional polymorphism (with alleles designated 5A or 6A) in the promoter of the MMP3 gene to examine the possible role of MMP3 in restenosis. METHODS AND RESULTS: Genotypes were determined in a series of consecutive patients who underwent conventional balloon coronary angioplasty without stenting (n=287) or who also had successful implantation of a Palmaz-Schatz stent (stent) (n=198). For all patients restenosis was estimated at 6 months using quantitative computer-assisted angiography. The minimal luminal diameters before and after the procedures did not differ significantly between genotypes. At follow-up in the patients without stent, those with the 6A6A genotype had an increased degree of restenosis after coronary angioplasty compared to those with one or more 5A alleles, with a greater diameter stenosis (52+/-21% vs 45+/-19%, P=0.012), and a greater late loss (0.58+/-0.59 mm vs 0.38+/-0.59 mm, P=0.038). By contrast, in the stented patients MMP3 genotype was not associated with any angiographically determined measure of vessel dimensions. CONCLUSIONS: These data imply the involvement of MMP3 in chronic remodelling after conventional balloon angioplasty, and suggest that the 6A6A MMP3 genotype is a genetic susceptibility factor for restenosis after angioplasty without stenting.     

白细胞介素-1及白细胞介素-1受体拮抗剂与经皮腔内血管成形术后再狭窄的关系

炎性反应是经皮腔内血管成形术后再狭窄的主要发病机制之一。炎性反应通过刺激内膜增生在支架置入术后再狭窄的过程中发挥重要作用。支架置入术后局部和系统炎性反应的强度和持续时间直接与患者的预后有关。白细胞介素（IL）-1在其发病过程中发挥了重要作用,而作为IL-1特异性的天然拮抗物IL-1受体拮抗剂（IL-1Ra）也越来越受到广泛的重视。本文就IL-1和IL-1Ra与再狭窄的关系作一综述。     

凝集素样氧化型低密度脂蛋白受体水平对冠状动脉支架置入术后再狭窄的预测价值

目的探讨冠状动脉粥样硬化性心脏病(冠心病)患者冠状动脉支架置入术后血清凝集素样氧化型低密度脂蛋白受体-1(Lox-1)变化趋势及与支架内再狭窄(ISR)的关系。方法连续入选经皮冠状动脉介入治疗并置入冠状动脉支架的冠心病患者128例。分别于术前和术后24h、1周、2周、1月、3月、6月时采集外周静脉血,测定血清Lox-1水平。所有患者术后6月常规复查冠状动脉造影,以支架内径狭窄≥50%为再狭窄,分为再狭窄组(n=24)和无再狭窄组(n=104),并分析两组患者血清Lox-1水平变化趋势及差别。结果术后24h两组患者血清Lox-1水平较术前明显增加,有统计学差异(P0.05);冠状动脉无再狭窄组患者术后1周血清Lox-1水平有下降趋势,2周时恢复至术前水平,术后1个月、3个月、6个月血清Lox-1水平与术前比较无统计学差异(P0.05)。冠状动脉再狭窄组患者血清Lox-1水平术后两周、术后1个月、3个月、6个月时血清Lox-1水平呈持续性升高,与无再狭窄组相比,差异有统计学意义(P0.05)。结论冠状动脉支架置入患者血清Lox-1水平在两周时基本恢复至术前水平,未恢复至术前水平且持续升高者发生支架内再狭窄危险性高。     

冠心病患者首次PTCA后发生再狭窄的危险因素分析

目的：探讨PTCA后再狭窄的危险因素,为防治PTCA后再狭窄提供依据。方法：对70例患PTCA的一般情况、PTCA有关数据,采用SPSS10．0软件进行分析。结果：再狭窄率为25．7％（18／70）。Logistic回归结果显示大量喝酒、糖尿病、缺少运动是再狭窄发生的危险因素,其相对危险度分别为18．122,7．528,4．906。首次PTCA时低年龄、男性相对容易发生再狭窄。结论：PTCA患（尤其是男性）不宜嗜酒,应控制血糖,更多活动。     

Association of a genetic variant of endothelial nitric oxide synthase with the 1 year clinical outcome after coronary stent placement.

AIMS: Endothelial nitric oxide synthase (eNOS) catalyzes the formation of nitric oxide which has vasodilatory, antithrombotic, antiinflammatory and antiproliferative properties. The TT genotype of the single nucleotide polymorphism 894 G/T, located in exon 7 of the eNOS gene, was found to be associated with coronary spasm, coronary artery disease (CAD) and myocardial infarction (MI). We investigated the possibility that the 894 TT genotype has an unfavorable impact on the angiographic and clinical outcome after the placement of stents in coronary arteries. METHODS AND RESULTS: Our study included 1850 patients with CAD who were treated with stent implantation. Major adverse clinical events, including death, MI, and target vessel revascularization, were recorded for 1 year after the intervention. Patients with genotype 894 TT had an increase in the risk of death or MI (hazard ratio 2.14, 95% confidence interval (CI) 1.23-3.72; p=0.007), if compared with G allele carriers. TT patients showed no significant increase in the risk for angiographic restenosis (odds ratio (OR) 1.11, 95% CI 0.78-1.56; p=0.56) and target vessel revascularization (OR 1.21, 95% CI 0.82-1.78; p=0.34). CONCLUSIONS: In comparison with eNOS 894 G allele carriers, patients of the TT genotype were at an increased risk of death or MI within 1 year after coronary artery stenting.     

冠心病患者首次PTCA后发生再狭窄的危险因素分析

目的探讨PTCA后再狭窄的危险因素,为防治PTCA后再狭窄提供依据.方法对70例患者PTCA的一般情况、PTCA有关数据,采用SPSS 10.0软件进行分析.结果再狭窄率为25.7%(18/70).Logistic回归结果显示大量喝酒、糖尿病、缺少运动是再狭窄发生的危险因素,其相对危险度分别为18.122,7.528,4.906.首次PTCA时低年龄、男性相对容易发生再狭窄.结论PTCA患者(尤其是男性)不宜嗜酒,应控制血糖,更多活动.     

川芎嗪防治冠心病经皮冠状动脉介入术后再狭窄的临床研究

目的　探讨中药川芎嗪防治经皮冠状动脉介入术 (PCI)后再狭窄的作用。方法　对 16 5例首次接受 PCI治疗的冠心病 (CAD)患者随机分为服用川芎嗪组和对照组。观察两组临床症状、心功能 (NYHA)状况并复查心电图、超声心动图和检验指标 ,部分病例行冠状动脉造影复查。术后随访 6～ 12个月。结果　术前和术中两组在冠心病危险因素、病变特点和手术参数等方面无显著差异 (P>0 .0 5 )。经 6～ 12个月随访 ,川芎嗪组再狭窄发生率(4 1.6 7% )明显低于对照组 (76 .19% ) ,P<0 .0 5。两组患者均未见服药不良影响。结论　川芎嗪具有防治 PCI术后再狭窄的良好临床效果 ,本研究为我国传统中药应用于 PCI术后再狭窄开辟了一条中西医结合的道路。     

冠心病PCI术后再狭窄的临床分析

目的：了解冠心病冠状动脉介入治疗（PCI）术后再狭窄的原因,为预防再狭窄发生提供根据。方法：回顾性分析我院冠脉支架置入300例中冠脉造影随访的74例的临床、血管造影及处理资料。并根据随访结果有、无再狭窄分为再狭窄组（42例）,无再狭窄组（32例）,分析病人年龄、性别、冠心病易患因素,靶病变形态学及术后最小管腔开放直径（MLD）等因素与再狭窄的关系。结果：与无再狭窄组比较,再狭窄组的男性（34.4%比76.2%）、吸烟（46.9%比71.4%）、PCI术后管腔直径〈3.5mm（40.0%比62.2%）显著增加。结论：男性、吸烟、支架直径〈3.5mm与PCI后冠状动脉再狭窄有关。     

Chlamydia pneumoniae seropositivity predicts the risk of restenosis after percutaneous transluminal coronary angioplasty

This study was done to evaluate whether anti-Chlamydia pneumoniae seropositivity can be a predictor of restenosis after coronary intervention. Recent studies indicate that latent infection with C. pneumoniae is associated with and could possibly cause atherosclerosis. However, it is unknown whether chronic infection with this microorganism is involved in the mechanism of restenosis after percutaneous transluminal coronary angioplasty. We prospectively studied 78 consecutive patients (90 target lesions) with symptomatic coronary artery disease who underwent successful coronary intervention to a de novo lesion (conventional balloon angioplasty to 31 lesions and stent implantation to 59 lesions). At angioplasty, blood samples were collected to measure the serum level of anti-C. pneumoniae IgG to examine whether seropositive patients were prone to restenosis and whether the seropositivity could predict the risk of restenosis determined by follow-up coronary angiography performed within 6 months after the angioplasty. Restenosis, defined as more than 50% stenosis with an increase of 15% or more in the degree of stenosis from that measured on cineangiograms after angioplasty, developed in 36 of 62 seropositive patients and in 4 of 16 seronegative patients (58% vs 25%, P = 0.025). Lesions in the seropositive patients had a greater mean loss index (mean ± SD 0.75 ± 0.45 vs 0.35 ± 0.41, P < 0.001), which was defined as late loss (luminal diameter reduction at follow-up angiography) divided by acute gain (luminal diameter gain by angioplasty), in late loss (1.07 ± 0.64 mm vs 0.65 ± 0.79 mm, P = 0.019), in percentage of diameter stenosis (57% ± 20% vs 41% ± 21%, P = 0.003) and a lesser mean in minimal luminal diameter (1.18 ± 0.58 mm vs 1.67 ± 0.63 mm, P = 0.002) at follow-up angiography. In a multivariate logistic regression model, anti-C. pneumoniae IgG seropositivity was a strong independent predictor of restenosis compared to the other risk factors (odds ratio = 6.2, P = 0.01). C. pneumoniae could play an important role in the mechanism of restenosis and evaluation of the IgG seropositivity, and may help to identify patients at high risk for restenosis. Received: June 13, 2001 / Accepted: December 7, 2001