Prevalence of Chlamydia pneumoniae in the atherosclerotic plaque of patients with unstable angina and its relation with serology

BACKGROUND: Chlamydia pneumoniae has been associated with coronary artery disease by both seroepidemiological studies, and by direct detection of the micro-organism in atherosclerotic lesions. This bacteria could play a potential role in the development of acute coronary events. We examined coronary arteries from patients with unstable angina in order to verify an endovascular presence of C. pneumoniae, and to determine if there is any relationship between serology of acute infection by this pathogen and its presence inside the atherosclerotic plaque of these patients. METHODS: We analysed a total of 76 atherosclerotic plaques obtained from 45 patients who underwent coronary artery bypass surgery. In all patients unstable angina was present within the prior 3 weeks. The presence of C. pneumoniae in the plaque was determined by nested polymerase chain reaction (PCR). Antichlamydial immunoglobulin G (IgG), A (IgA) and M (IgM) was examined by microimmunofluorescence and compared to the PCR result. FINDINGS: DNA of C. pneumoniae was detected in 57 (75%) of 76 atherosclerotic lesions. In most cases (74/76: 97%) a positive IgA, IgM or IgG result was seen. Seven (12%) and 54 (94%) of the 57 PCR positive plaques came from patients with a positive IgM and IgA result, respectively. There was no statistical significant difference between PCR positive and PCR negative plaques in patients with a positive or negative serological result. Clinical characteristics were similarly distributed in patients with and without infected lesions. INTERPRETATION: C. pneumoniae organisms are frequently found in the atherosclerotic lesions of patients undergoing coronary surgery for unstable angina. Neither serological results of acute or recent infection by C. pneumoniae nor clinical characteristics are useful in predicting the individual risk of harbouring C. pneumoniae in the coronary lesions of patients with unstable angina.     

Internal mammary artery atherosclerosis in segments removed during coronary artery bypass grafting surgery and C.pneumoniae infection.

OBJECTIVE: Recent studies suggest the association of atherosclerotic cardiovascular disease with Chlamydia pneumoniae infection. We investigated C. pneumoniae DNA in internal mammarian artery (IMA) (used as a coronary bypass conduit) and its relationship with atherosclerosis. METHODS: Sixty-six consecutive patients who underwent coronary artery bypass grafting (CABG) during an eight-month period were included in this study. From all patients, we attempted to obtain surplus segments of harvested IMA grafts. The vessels were examined histopathologically, and presence of C. pneumoniae DNA in IMA grafts was assessed by polymerase chain reaction (PCR). RESULTS: C. pneumoniae DNA was found in 7 (10.6%) of 66 IMA specimens. The light microscopic examinations of IMA segments from the C. pneumonia positive group showed atherosclerotic intimal changes in four of the seven patients. These atherosclerotic changes were type II in three patients and type III in one patient according to the AHA classification. The rest of the IMA segments from 62 patients did not show any discernible atherosclerotic lesion. CONCLUSION: The IMA graft examination by PCR and histopathology may be helpful in the determination of future graft patency for IMA bypass surgery.     

Chlamydia pneumoniae infection and atherosclerotic coronary disease.

BACKGROUND: Previous works have suggested an association between Chlamydia pneumoniae infection and coronary heart disease. We evaluated the prevalence of C. pneumoniae infection in patients with acute myocardial infarction (AMI) and coronary heart disease (CHD). METHODS AND RESULTS: Ninety-eight patients with AMI, 80 patients with CHD, and 50 control subjects matched for age and sex were investigated. Immunoglobulin (Ig)M, IgG, and IgA antibodies to C pneumoniae were measured by the microimmunofluorescence test. IgM antibodies were not found; IgG positivity was found in 58.2% of the AMI group, 60.0% of the CHD group, and 38% of the control group, whereas for IgA, positivity was found in 33.7%, 43.7%, and 22% of cases in AMI, CHD, and control groups, respectively. Titers indicating reinfection were found in AMI and CHD groups in 6.1% and 10%, respectively, whereas titers indicating chronic infection were found in 14% of the AMI group and 25% of the CHD group. A significant correlation was found between chronic C pneumoniae infection and dyslipidemias in the AMI and CHD groups (P =.003; P =. 0006). CONCLUSIONS: The results suggest that chronic C pneumoniae infection may be associated with the development of atherosclerotic coronary disease. In our next step, we will test whether antichlamydial antibiotics may help to reduce the risk of atherosclerotic disease.     

Detection of Chlamydia pneumoniae and Helicobacter pylori in atherosclerotic plaques of carotid artery by polymerase chain reaction.

OBJECTIVES: A possible role of some microorganisms has been proposed in the pathogenesis of atherosclerosis, but it is still an unresolved issue. We investigated the presence of Chlamydia pneumoniae and Helicobacter pylori DNA in carotid artery atherosclerotic plaques by using PCR. METHODS: One hundred and four patients with atherosclerotic diseases were included. The study group consisted of 52 atherosclerotic plaque specimens obtained from the carotid arteries of patients who had carotid endarterectomy and the control group consisted of 52 specimens obtained from the macroscopically healthy regions of ascending aorta in patients who had undergone coronary artery bypass grafting. The presence of C. pneumoniae and H. pylori DNA in endarterectomy specimens were demonstrated by PCR. RESULTS: C. pneumoniae DNA was detected in 16 of 52 (30.8%) atherosclerotic plaques and 1 of 52 (1.9%) macroscopically healthy ascending aorta wall specimens (P < 0.001). H. pylori DNA was detected in 9 of 52 (17.3%) atherosclerotic plaques and none of the controls (P = 0.003). CONCLUSIONS: The higher incidence of C. pneumoniae and H. pylori DNA in atherosclerotic plaques suggests that these microorganisms may play a role in the pathogenesis of atherogenesis.     

Chlamydia pneumoniae (TWAR) in coronary arteries of young adults (15-34 years old).

An association of Chlamydia pneumoniae with atherosclerosis of coronary and carotid arteries and aorta has been found by seroepidemiology and by demonstration of the organism in atheromata. Age-matched control tissue from persons without atherosclerosis was usually not available. We studied autopsy tissue from young persons, many with no atherosclerosis, to determine whether C. pneumoniae is present in atheroma in young persons with early atherosclerosis and to compare the findings in age- and sex-matched persons without atherosclerosis. A left anterior descending coronary artery sample, formalin-fixed, from 49 subjects, 15-34 years of age, from the multicenter study called Pathobiological Determinants of Atherosclerosis in Youth (PDAY), was examined by immunocytochemistry and the polymerase chain reaction (PCR) for the presence of C. pneumoniae and by PCR for cytomegalovirus. A hematoxylin/eosin-stained section was used to determine disease present in the studied sample. Seven of the artery samples were found to have atheromatous plaque, 11 had intimal thickening, and 31 had no lesions. Eight of the samples were positive for C. pneumoniae by immunocytochemistry (n = 7) and/or PCR (n = 3). Six of the 7 (86%) atheroma, 2 of the 11 (18%) with intimal thickening, and none of the 31 normal-appearing coronary samples were positive. Four were positive by PCR for cytomegalovirus, 2 from diseased arteries and 2 from normal arteries. Examination of the adjacent left coronary artery sample with a fat stain found abnormalities in 25 of the patients, but 19 still showed no evidence of atherosclerosis as a result of either examination. Thus, C. pneumoniae is found in coronary lesions in young adults with atherosclerosis but is not found in normal-appearing coronary arteries of both persons with and without other evidence of atherosclerosis.     

Demonstration of intracellular microorganisms (Rickettsia spp., Chlamydia pneumoniae, Bartonella spp.) in pathological human aortic valves by PCR

OBJECTIVES: Rickettsiae, which causes vasculitis, has not been linked to atherosclerotic cardiovascular disease in contrast to Chlamydia pneumoniae whose association with coronary artery disease and with sclerotic heart valves in patients undergoing aortic valve replacement is well established, even if causality is yet to unproven. In the search for any of these infectious agents, 84 pathological and 15 normal aortic heart valves of patients undergoing forensic autopsy were analysed by PCR and DNA-sequencing. METHODS: Two to four pieces of all valves were examined by semi-nested PCR, with primers specific for 16S rDNA, citrate synthase (gltA) and 17 kDa outer membrane protein (OMP) genes. RESULTS: Genetic material from Rickettsia spp. and C. pneumoniae was found in 17 (20.2%) and 22 (26.2%), respectively, of the 84 pathological aortic valves. In 35 (41.7%) of these 84 valves either C. pneumoniae or Rickettsia spp. were detected by PCR and in six cases (7.1%) these two organisms co-existed. In one case with Lambl's excrescences, previously considered as aseptic, presence of rickettsia-like organisms also was demonstrated by light microscopy, immunohistochemistry and sequencing of the amplified PCR product showing 100% homology with the published sequence for R. helvetica. In three of the 15 control valves, genetic material from only C. pneumoniae was detected compared to Rickettsia spp. that was significantly detected only in the pathological valves (Fisher's Exact test, 1-sided p = 0.046). CONCLUSIONS: The findings suggest that Rickettsia spp. also have a role in the pathogenesis of aortic valve disease.     

Is there a role for Chlamydia pneumoniae infection in systemic lupus erythematosus and in the associated atherosclerotic cardiovascular disease?

OBJECTIVE: To search for molecular evidence of Chlamydial infection in systemic lupus erythematosus (SLE) subjects and to assess if there is an association of this infectious agent with coronary artery calcification (CAC), a marker of total atherosclerotic burden. METHODS: 28 SLE subjects had blood samples drawn and DNA extracted from peripheral blood mononuclear cells (PBMC) and an electron beam computed tomography (EBCT) scan. Polymerase chain reaction (PCR) analysis was performed for Chlamydia trachomatis 16srRNA and major outer membrane protein (MOMP) and for C. pneumoniae 16srRNA, MOMP, as well as nested PCR for MOMP. RESULTS: Four of 28 subjects (14.2%) had evidence of C. pneumoniae nucleic acid in PBMC. The 16srRNA primers detected C. pneumoniae in one patient (3.57%) and the nested PCR MOMP primers in 3 subjects (10.71%). None were positive for Chlamydia trachomatis. Two of the 4 subjects with C. pneumoniae DNA had abnormal EBCT scans and 2/11 (18.3%) subjects with abnormal EBCT were positive for C. pneumoniae. There were significant associations of C. pneumoniae DNA with smoking (OR = 3) and corticosteroid use. The odds ratio for subjects with abnormal CAC and detectable C. pneumoniae was 1.67. CONCLUSION: This pilot study demonstrates for the first time that C. pneumoniae DNA can be identified in the PBMC of some SLE subjects and there may be an association with CAC. Smoking may be an additional risk factor for infection in this population. Determination of pathogenicity of this organism in atherosclerotic coronary vascular disease in SLE will require further study.     

The adventitia of atherosclerotic coronary arteries frequently contains Chlamydia pneumoniae.

The presence of Chlamydia pneumoniae in the human arterial system has mainly been determined in atherosclerotic plaque, whereas the adventitia has remained relatively unexplored. We assessed the presence of C. pneumoniae in all three vessel wall layers of coronary (n=72) and brachial (n=48) arteries in relation to local atherosclerosis. Immunohistochemical staining of C. pneumoniae was observed in plaque and adventitia. Cells stained for C. pneumoniae were detected in the same areas as cells stained for macrophages in adjacent sections. C. pneumoniae staining in the adventitia was associated with the extent and severity of atherosclerosis. Coronary sections with C. pneumoniae staining in both adventitia and plaque more often contained advanced atherosclerosis than sections with staining only in the adventitia. Staining was observed more often in the coronary artery than in the brachial artery (24/72 vs. 5/48 and 51/72 vs. 8/48 for plaque and adventitia, respectively, P=0.004 and P<0.001). PCR confirmed the presence of C. pneumoniae DNA in the adventitia. In summary, the adventitia of atherosclerotic coronary arteries frequently contains C. pneumoniae that seems to be located within macrophages. These results might indicate a possible route for infected circulating macrophages to home into atherosclerotic lesions in the artery via vasa vasorum.     

Low prevalence of Chlamydia pneumoniae in atherectomy specimens from patients with coronary heart disease.

Coronary atherectomy specimens from 50 patients with coronary heart disease were examined for the presence of Chlamydia pneumoniae by two different methods of polymerase chain reaction (PCR) and by in situ hybridization. C. pneumoniae DNA was detected by PCR in atherosclerotic plaques of four patients (8%). Two patients' coronary atheromas were positive, both by a single-step 16S rRNA-based PCR and by an omp1-based nested PCR. The other two patients' specimens were positive only by the nested PCR. In contrast, C. pneumoniae was not detected by in situ hybridization in any of the cardiovascular tissues tested. Of three patients with evidence of C. pneumoniae in coronary atheromas, two had an antibody titer of 1:32 and the third had no specific antibodies detectable. Results of this study demonstrate a low prevalence of C. pneumoniae DNA in coronary atheromas. These findings do not support the hypothesis that the organism plays a major role in atherogenesis.     

血凝素样氧化型低密度脂蛋白1基因多态性与汉族老年患者冠状动脉病变的关系

目的 分析老年汉族冠心病患者血凝素样氧化型低密度脂蛋白1(lectin-like oxidized low-density lipoprotein receptor-1,LOX-1)501G/C和3'UTR位点C/T基因多态性与冠状动脉病变支数及狭窄程度的关系.方法 选择行冠状动脉造影患者165例,根据冠状动脉造影结果...     

Chlamydia pneumoniae DNA is more frequent in advanced than in mild atherosclerosis lesions

There is growing evidence of an association between Chlamydia pneumoniae infection and atherosclerosis. By using polymerase chain reaction (PCR), we detected the presence of C. pneumoniae DNA in 16 of 92 (17%) arterial specimens with severe atherosclerotic lesions, and in 3 of 109 (3%) such specimens with mild atherosclerotic lesions (p < 0.01) from 49 cases with an autopsy diagnosis of cardiac death and 5 patients who underwent vascular reconstructive surgery. 14 of the 54 cases (28%) were C. pneumoniae-positive in at least 1 vascular sample. 12 of the 14 (86%) PCR positive cases were aged 60 y or older. Normal pulmonary artery specimens from 24 autopsy cases, used as a methodological control, tested negative. The levels of low density lipoprotein cholesterol and triglycerides were significantly lower in the PCR-positive cases than in the PCR-negative cases (p < 0.05). Importantly, 11 of the 14 PCR-positive cases had only 1 risk factor for atherosclerotic cardiovascular disease, whereas all PCR-negative cases had multiple risk factors (p < 0.05). Our data support the idea that C. pneumoniae may be involved in the development of atherosclerosis in humans, especially in cases where classic risk factors are not identified to explain the incidence of atherosclerotic vascular disease.     

Relation of secretory phospholipase A(2) and high-sensitivity C-reactive protein to Chlamydia pneumoniae infection in acute coronary syndromes.

BACKGROUND: Recently it has become clear that inflammatory changes play a part in the development of atherosclerosis, including coronary artery disease, and Chlamydia pneumoniae (C. pneumoniae) is thought to be a proinflammatory factor. The plasma concentration of high-sensitive C-reactive protein (hs-CRP) is a potential predictor of outcome in atherosclerotic diseases. Recent interest has focused on secretory group IIA phospholipase A(2) (sPLA (2)) in regard to the progression of atherosclerotic disease. METHODS AND RESULTS: The concentrations of sPLA(2), hs-CRP, and the titers of C. pneumoniae IgG and IgA antibodies were measured in blood samples. The study groups were an acute coronary syndrome (ACS) group, old myocardial infarction/angina pectoris (OMI/AP) group, and a control group. The concentrations of sPLA(2) and hs-CRP in the ACS group and the OMI/AP group were higher than in the control group. The titers of C. pneumoniae IgG and IgA were higher in the ACS group than in the control group. The sPLA(2) concentration was higher in those who were positive to C. pneumoniae IgG/IgA than in those who were negative. CONCLUSION: Increased concentrations of sPLA(2) reflect participation in the progression of coronary artery disease. The sPLA(2) concentration was higher in patients positive for C. pneumoniae than in those negative for C. pneumoniae, so C. pneumoniae infection poses a greater risk for ACS in those individuals than in those who are free of such infection.     

Serological evidence of Chlamydia pneumoniae lipopolysaccharide antibodies in atherosclerosis of various vascular regions

BACKGROUND: The role of Chlamydia pneumoniae in the pathogenesis of atherosclerosis has so far mainly been investigated in patients suffering from coronary heart disease; the other vascular regions have virtually been ignored. The aim of this study was to carry out a statistical survey of serological markers of a C. pneumoniae infection in patients with different patterns of atherosclerosis manifestation. PATIENTS AND METHODS: 340 patients were examined for the atherosclerotic alteration of peripheral arteries of the lower limbs, carotid arteries and coronary arteries by ultrasound scan and/or angiography. Immunoglobulin(Ig)G and IgA-rELISA were used to measure chlamydial lipopolysaccharide antibodies. Species determination was performed using the IgG micro-immunofluorescence test. RESULTS: 24.0% of atherosclerotic cases (A) and 52.3% of controls (C) were negative for C. pneumoniae lipopolysaccharide antibodies (p = 0.00002). By contrast, 45.1% of atherosclerotic cases and 16.9% of controls were positive for both IgG and IgA (p = 0.00002). The mean antibody titers of the atherosclerosis group were higher than in the control group (IgG positive xAIgG = 344, xCIgG = 272; IgG and IgA positive xAIgG = 576, xCIgG = 486 and xAIgA = 120, xCIgA = 91). Concerning atherosclerosis manifestation in various vascular regions, no significant differences were found between IgG and IgA antibody titers and prevalence. CONCLUSIONS: The results show that a persistent C, pneumoniae infection with evidence of lipopolysaccharide immunoglobulin G and A is equally associated with the atherosclerotic alteration of coronary arteries, carotid arteries and peripheral arterial occlusive disease, irrespective of the severity of atherosclerosis and with no predisposition to any particular vascular region.     

Correlation of hyperhomocysteinaemia and Chlamydia pneumoniae IgG seropositivity with coronary artery disease in a general population

BACKGROUND: Both Chlamydia pneumoniae infection and hyperhomocysteinaemia have been assumed to increase the atherosclerotic risk independently of each other and independently of the classic risk factors. The correlation between hyperhomocysteinaemia, C. pneumoniae infection and coronary artery disease (CAD) have not been investigated in the general population. METHODS: In an ancillary study to the Persian Gulf Healthy Heart Study, a cohort study of men and women aged >or=25 years, a random sample of 1699 (48.9% males, 51.1% females) subjects were evaluated. Total homocysteine, high sensitivity C-reactive protein (CRP) and IgG antibodies to C. pneumoniae were determined by ELISA. Minnesota coding criteria of a 12-lead resting electrocardiogram was used for evaluation of CAD. RESULTS: A total of 12.4% of the subjects had electrocardiogram-defined (Minnesota-coding criteria) coronary artery disease. Hyperhomocysteinaemia (>14 micromol/l) and IgG seropositivity were found in 50.8% and 37.7%, respectively. Neither of hyperhomocysteinaemia nor C. pneumoniae IgG seropositivity showed a significant association with CAD after adjusting of sex and age. Concurrent elevated CRP level (>8.2mg/l) and C. pneumoniae seropositivity (chronic C. pneumoniae infection) had a significant association with CAD [OR=1.73, CI (1.09-2.75); p=0.01] after adjusting for age, sex, systolic and diastolic blood pressures, BMI, and serum levels of LDL-cholesterol, fasting blood sugar and triglyceride as covariates in a logistic regression model. This odds ratio increased to 2.11, CI (1.18-4.12; p=0.02) when concurrent hyperhomocysteinaemia and chronic C. pneumoniae infection, as a single covariate entity; was adjusted for multiple risk factors in another logistic regression model. CONCLUSION: Concurrent hyperhomocysteinaemia and chronic C. pneumoniae infection, as a single entity, was independently associated with coronary artery disease in the general population. This synergism may have important implications for risk-stratification and intervention trials.     

Coronary artery disease: an inflammatory or infectious process

It is well accepted that coronary artery disease is linked to an inflammatory process. It is unknown which agents may cause or accelerate coronary artery disease. An inflammation of the vessel wall may be caused by a number of mechanisms such as accumulation of glycosylated proteins in diabetic patients, oxidised LDL in patients with hypercholesterolemia or infectious agents. Among the possible infectious agents Chlamydia pneumoniae is the most likely microorganism involved in atherosclerosis. The arguments in favour of Chlamydia pneumoniae result from seroepidemiologic studies and from detection of chlamydial DNA in atherosclerotic plaques by polymerase chain reaction (PCR). In addition this microorganism is the only one that could be isolated from atherosclerotic tissue. This review summarises the present understanding of the role of an inflammatory process in the development or progression of coronary artery disease.     

Failure to detect Chlamydia pneumoniae in aortic valves and peripheral blood mononuclear cells from patients undergoing aortic valve replacement in Norway

The association of Chlamydia pneumoniae with atherosclerosis is still controversial. Reports from different laboratories have varied widely and "gold standards" for the detection of C. pneumoniae are lacking. In the present study, aortic valves and peripheral blood mononuclear cells from 48 patients undergoing aortic valve replacement were examined for the presence of C. pneumoniae using a nested PCR. C. pneumoniae-specific DNA was not detected in any of the clinical samples. No PCR inhibition was observed by spiking the samples with target C. pneumoniae. A total of 31/46 patients (67%) were seropositive for C. pneumoniae IgG. These results do not support the association of C. pneumoniae with aortic valves and peripheral blood mononuclear cells in patients with atherosclerotic aortic heart valve disease.     

成人冠状动脉左前降支粥样硬化斑块中检测出肺炎衣原体

为了探索肺炎衣原体感染和冠状动脉粥样硬化之间的关系、利用肺炎衣原体主要外膜蛋白基因上的保守序列设计的3条引物，通过多聚酶链反应检测32例冠状动脉左前降支粥样硬化斑块以及7例正常冠状动脉左前降支中肺炎衣原体。结果发现，32例有粥样硬化斑块的冠状动脉左前降支中有14例多聚酶链反应阳性．阳性率为43．75％，7例正常冠状动脉中无一例阳性，阳性率为0％。结果提示肺炎衣原体在有粥样硬化冠状动脉和正常冠状动豚中存在显著差异。     

Detection of Chlamydia pneumoniae but not cytomegalovirus in occluded saphenous vein coronary artery bypass grafts

BACKGROUND: A causal relation between atherosclerosis and chronic infection with Chlamydia pneumoniae and/or cytomegalovirus (CMV) has been suggested. Whether the unresolved problem of venous coronary artery bypass graft occlusion is related to infection with C pneumoniae and/or CMV has not been addressed. METHODS AND RESUTLS: Thirty-eight occluded coronary artery vein grafts and 20 native saphenous veins were examined. Detection of C pneumoniae DNA was performed by use of nested polymerase chain reaction (PCR). Homogenisates from the specimen were cultured for identification of viable C pneumoniae. Both conventional PCR and quantitative PCR for detection of CMV DNA were applied. Differential pathological changes (degree of inflammation, smooth muscle cell proliferation [MIB-1]) were determined and correlated to the detection of both microorganisms. C pneumoniae DNA could be detected in 25% of occluded vein grafts. Viable C pneumoniae was recovered from 16% of occluded vein grafts. Except for 1 native saphenous vein, all control vessels were negative for both C pneumoniae detection and culture. All pathological and control specimens were negative for CMV DNA detection. Pathological changes did not correlate with C pneumoniae detection. CONCLUSIONS: Occluded aorto-coronary venous grafts harbor C pneumoniae but not CMV. The detection of C pneumoniae in occluded vein grafts warrants further investigation.     

Systemic inflammation,Chlamydia pneumoniae DNA in circulating leukocytes and coronary atherosclerosis

OBJECTIVE: Earlier studies have suggested that C. pneumoniae may be involved in the progression of atherosclerosis by contributing to the pathogenesis of inflammation in the vessel wall. The aim of the present study was to determine the prevalence of C. pneumoniae DNA in circulating white blood cells of patients with ischaemic heart disease and to correlate these findings with the extent of coronary atherosclerosis and serum markers of inflammation. METHODS AND RESULTS: In 203 consecutive patients undergoing diagnostic coronary angiography for different coronary syndromes, presence of C. pneumoniae DNA in circulating leukocytes could not be demonstrated by the polymerase chain reaction. Serum concentrations of CRP were significantly higher in patients with significant coronary artery disease compared to those with normal coronary arteries. In addition, patients with a three-vessel disease had significantly higher serum CRP compared to patients with diffuse, non-critical coronary atherosclerosis. A positive correlation was found between serum fibrinogen and serum CRP. CONCLUSION: In spite of a significant relation between serum CRP and the extent of atherosclerotic coronary artery disease, we were unable to detect C. pneumoniae DNA in circulating white blood cells. This observation suggests that there is no relation between circulating C. pneumoniae, systemic inflammation and extent of coronary atherosclerosis.     

The Study of Chlamydia Pneumoniae DNA in the Peripheral Blood Mononuclear Cell of Coronary Heart Disease

Cardiovascular disease is the leading cause of death in developed countries. The cause is multifactori- al. A substantial proportion of patients with coronary artery disease do not have traditional risk factors. Therefore, scientific attention has recently focused on investigating hypothetical additional risk factors and on achieving a deeper understanding of the development of atherosclerosis . Infectious diseases may play a role in these cases , or they may intensity the effect of other risk…