Modulation of calcification of vascular smooth muscle cells in culture by calcium antagonists, statins, and their combination

Background Vascular calcification is an organized process in which vascular smooth muscle cells (VSMCs) are implicated primarily. The purpose of the present study was to assess the effects of calcium antagonists and statins on VSMC calcification in vitro. Methods VSMC calcification was stimulated by incubation in growth medium supplemented with 10 mmol/l β-glycerophosphate, 8 mmol/l CaCl2, 10 mmol/l sodium pyruvate, 1 μmol/l insulin, 50 μg/ml ascorbic acid, and 100 nmol/l dexamethasone (calcification medium). Calcification, proliferation, and apoptosis of VSMCs were quantified. Results Calcium deposition was stimulated dose-dependently by β-glycerophosphate, CaCl2, and ascorbic acid (all P < 0.01). Addition of amlodipine (0.01–1 μmol/l) to the calcification medium did not affect VSMC calcification. However, atorvastatin (2–50 μmol/l) stimulated calcium deposition dose-dependently. Combining treatments stimulated calcification to a degree similar to that observed with atorvastatin alone. Both atorvastatin and amlodipine inhibited VSMC proliferation at the highest concentration used. Only atorvastatin (50 μmol/l) induced considerable apoptosis of VSMCs. Conclusion In vitro calcification of VSMCs is not affected by amlodipine, but is stimulated by atorvastatin at concentrations ≥10 μmol/l, which could contribute to the plaque-stabilizing effect reported for statins

The connection between C‐reactive protein and atherosclerosis

The connection between C-reactive protein (CRP) and atherosclerosis lies on three grounds. First, the concentration of CRP in the serum, which is measured by using highly sensitive (a.k.a. ‘hs’) techniques, correlates with the occurrence of cardiovascular disease. Second, although CRP binds only to Fcγ receptor-bearing cells and, in general, to apoptotic and damaged cells, almost every type of cultured mammalian cells has been shown to respond to CRP treatment. Many of these responses indicate proatherogenic functions of CRP but are being reinvestigated using CRP preparations that are free of endotoxins, sodium azide, and biologically active peptides derived from the protein itself. Third, CRP binds to modified forms of low-density lipoprotein (LDL), and, when aggregated, CRP can bind to native LDL as well. Accordingly, CRP is seen with LDL and damaged cells at the atherosclerotic lesions and myocardial infarcts. In experimental rats, human CRP was found to increase the infarct size, an effect that could be abrogated by blocking CRP-mediated complement activation. In the Apob(100/100)Ldlr (-/-) murine model of atherosclerosis, human CRP was shown to be atheroprotective, and the importance of CRP-LDL interactions in this protection was noted. Despite all this, at the end, the question whether CRP can protect humans from developing atherosclerosis remains unanswered

Patients enrolled in coronary intervention trials are not representative of patients in clinical practice: Results from the Euro Heart Survey on Coronary Revascularization

Aims: Revascularization in patients with coronary artery disease changed over the last two decades, favouring the number of patients treated by means of percutaneous coronary interventions (PCI) when compared with coronary artery bypass grafting (CABG). Many randomized controlled trials (RCTs) have been performed to compare these two competing revascularization techniques. Because of the strict enrolment criteria of RCTs in which highly selected patients are recruited, the applicability of the results may be limited in clinical practice. The current study evaluates to what extent patients in clinical practice were similar to those who participated in RCTs comparing PCI with CABG. Methods and results: Clinical characteristics and 1-year outcome of 4713 patients enrolled in the Euro Heart Survey on Coronary Revascularization were compared with 8647 patients who participated in 14 major RCTs, comparing PCI with CABG. In addition, we analysed which proportion of survey patients would have disqualified for trial participation (n = 3033, 64%), aiming at identifying differences between trial-eligible and trial-ineligible survey patients. In general, important differences were observed between trial participants and survey patients. Patients in clinical practice were older, more often had comorbid conditions, single-vessel disease, and left main stem stenosis when compared with trial participants. Almost identical differences were observed between trial-eligible and trial-ineligible survey patients. In clinical practice, PCI was the treatment of choice, even in patients who were trial-ineligible (46% PCI, 26% CABG, 28% medical). PCI remained the preferred treatment option in patients with multi-vessel disease (57% in trial-eligible and 40% in trial-ineligible patients, respectively, P < 0.001); yet, the risk profile of patients treated by PCI was better than that for patients treated either by CABG or by medical therapy. In the RCTs, there was no mortality difference between PCI and CABG. In clinical practice, however, we observed 1-year unadjusted survival benefit for PCI vs. CABG (2.9 vs. 5.4%, P < 0.001). Survival benefit was only observed in trial-ineligible patients (3.3 vs. 6.2%, P < 0.001). Conclusion: Many patients in clinical practice were not represented in RCTs. Moreover, only 36% of these patients were considered eligible for participating in a trial comparing PCI with CABG. We demonstrated that RCTs included younger patients with a better cardiovascular risk profile when compared with patients in everyday clinical practice. This study highlights the disparity between patients in clinical practice and patients in whom the studies that provide the evidence for treatment guidelines are performed. © The European Society of Cardiology 2006. All rights reserved

Breast Arterial Calcification: a New Marker of Cardiovascular Risk?

Mammographically-detected breast arterial calcifications (BAC) are considered to be an incidental finding without clinical importance since they are not associated with increased risk of breast cancer. The goal of this article is to review existing evidence that the presence of BAC on mammography correlates with several (but not all) traditional cardiovascular disease (CVD) risk factors and with prevalent and incident CVD. Thus, BAC detected during routine mammography is a noteworthy finding that could be valuable in identifying asymptomatic women at increased future CVD risk that may be candidates for more aggressive management. In addition, there are notable differences in measures of subclinical atherosclerosis burden in women (ie, coronary artery calcification) by race/ethnic background, and the same appears to be true for BAC, although data are very limited. Another noteworthy limitation of prior research on BAC is the reliance on absence vs presence of BAC; no study to date has determined gradation of BAC. Further research is thus required to elucidate the role of BAC gradation in the prediction of CVD outcomes and to determine whether adding BAC gradation to prediction models based on traditional risk factors improves classification of CVD risk