Glycemic control in type 2 diabetes mellitus prevents coronary arterial wall infection.

BACKGROUND: Diabetes mellitus (DM) is a very well-known risk factor for development of atherosclerosis, and it has been hypothesized that poor glycemic control and hyperglycemia plays a major role in this process. In the current study, we aimed to evaluate the associates of poor glycemic control in Iranian patients who have already undergone coronary artery bypass grafting (CABG), with especial focus on the inhabitation of infectious agents within the coronary arterial wall. METHODS: In January 2010, 52 consecutive patients with type 2 DM who undergone CABG at the Department of Cardiovascular Surgery of Baqiyatallah University of Medical Sciences (Tehran, Iran) were included into this cross-sectional study and biopsy specimens from their coronary plaques were taken and analyzed by polymerase chain reaction (PCR) methods for detecting Helicobacter species, cytomegalovirus (CMV) and Chlamydia pneumoniae, and their potential relation to the glycemic control status in these patients. RESULTS: Compared to that in diabetic patients with mean fasting blood sugar (FBS) levels FBS < 126, atherosclerotic lesions in type 2 diabetic patients with poor glycemic control (FBS > 126) were significantly more likely to be positive for CMV PCR test (41% vs. 9%, respectively; P = 0.05). In laboratorial test results, mean triglyceride level was significantly higher among patients of poor glycemic control (168 ± 89 vs. 222 ± 125 mg/dl, respectively; P = 0.033). Hypertension was also significantly more prevalent in this population (73% vs. 36%, respectively; P = 0.034). CONCLUSION: Type 2 diabetic patients with poor glycemic control can be at higher risk for developing CMV infection in their coronary arterial wall, which can promote atherosclerosis formation process in this patient population. According to the findings of this study, we recommend better control of serum glucose levels in type 2 diabetic patients to prevent formation/progression of atherosclerosis.

Chlamydia pneumoniae in the atherosclerotic plaques of coronary artery disease patients.

An association between Chlamydia pneumoniae (C. pneumoniae) and cardiovascular disease has been demonstrated. In this study, we aimed to study this potential relationship in 105 Iranian patients. Coronary artery specimens from 105 Iranian patients undergoing CABG were analyzed by PCR method for C. pneumoniae. Serological evaluation for C. pneumoniae IgG and IgM was performed using ELISA. 53 specimens from mamillary artery were also investigated. C. pneumoniae PCR test result was positive for 23 (21.9%) of patients with coronary artery atherosclerosis, but none of the specimens from the mamillary artery was positive for C. pneumoniae when it was evaluated by the PCR (P<0.001). Coronary artery disease patients with and without a history of unstable angina or myocardial infarction were comparable in C. pneumoniae PCR test positive rates (P=0.618). Relevance of IgG and IgM positivity were also studied by correlating it to the study parameters, but no difference was found. CRP was significantly higher in the IgM positive group (P<0.001). A significant proportion of coronary atherosclerotic plaques are infected with C. pneumoniae while no infection was found in the normal mamillary artery specimens. No association was found between acute coronary syndromes and serological and PCR positivity. Further prospective randomized controlled studies with large patient population are needed to confirm our findings.

Cytomegalovirus localization in atherosclerotic plaques is associated with acute coronary syndromes: report of 105 patients.

It has been shown that cytomegalovirus (CMV) is present in coronary atherosclerotic plaques, but the clinical relevance of this presence remains to be elucidated. In this study we sought to examine CMV infection in atherosclerosis patients defined by different methods and to identify the clinical significance of CMV replication in the atherosclerotic plaques. The study included 105 consecutive patients who were admitted to our department and underwent coronary artery bypass grafting (CABG) surgical interventions. Coronary atherosclerotic specimens as well as 53 specimens from the mamillary artery of these same patients were analyzed. Enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) methods were used for evaluations. The CMV PCR test result was positive for 28 (26.7%) of patients with coronary artery atherosclerosis. After adjusting for other risk factors, coronary artery disease patients with a history of acute coronary syndrome were more likely to be positive for CMV PCR test (P=0.027; odds ratio: 4.2; 95% CI: 1.18-15.0). They were also more likely to have a positive family history for cardiovascular diseases (CVD). This study confirms previous evidence about the replication of CMV virus in the atherosclerotic plaques of coronary arteries and brings clinical significance to this observation by showing a higher prevalence of acute coronary syndromes in those patients with CMV-infected plaques. Our study also suggests a familial vulnerability to CMV replication in the coronary artery walls.

Helicobacter species in the atherosclerotic plaques of patients with coronary artery disease.

INTRODUCTION: Several epidemiological studies have proposed an association between Helicobacter pylori infection and coronary artery disease. In the current study, we aimed to evaluate the prevalence and relevance of H. pylori infection, using polymerase chain reaction (PCR) methods, in the coronary arterial wall of Iranian patients who have already undergone coronary bypass grafting (CABG). METHODS: A total of 105 consecutive patients who underwent CABG at the Department of Cardiovascular Surgery of Baqiyatallah University of Medical Sciences were included in the study, and biopsy specimens from their coronary plaques were taken and analyzed using the PCR methods for detecting Helicobacter species (H Spp.). Fifty-three specimens from biopsies of the left internal mamillary artery in the same patients were also collected and tested. RESULTS: H. Spp. PCR test result was positive for 31 (29.5%) specimens from coronary artery atherosclerotic plaques. Serologic test results also showed 25 (23.8%) positive cases for H. pylrori immunoglobulin A (IgA) and 56 (53.3%) positive for anti-H. pylori immunoglobulin G. None of the specimens from the mamillary artery were positive for H Spp. genome when it was evaluated using PCR (P<.0001). Patients with positive test result for H. pylori IgA were significantly more likely to have higher total cholesterol and low-density lipoprotein (LDL) levels than IgA-negative patients. CONCLUSION: H Spp. infection replication in the coronary arterial wall is associated with atherosclerotic plaque formation. Seropositivity for H. pylori IgA may also enhance blood values of total cholesterol and LDL in these patients.