RESUMEN
The arterial endothelium is a complex organ that modulates vascular tone by release of various substances to control perfusion. Endothelial function reflects vascular ageing and health. Already at the earliest stages of atherosclerosis the delicate balance between arterial constriction and relaxation is disturbed. Therefore, non-invasive assessment of endothelial function is a means to identify patients at increased cardiovascular risk, even at levels of disease that cannot be identified with classical imaging techniques that depict arterial wall and/or lumen or with functional assessment of ischaemia. Currently, there is an increasing interest in the early recognition of endothelial dysfunction to streamline and optimise preventive therapeutic measures. In this article, several methods for the assessment of endothelial function are briefly reviewed. In particular, we discuss the fast bed-side assessment of endothelial function by the reactive hyperaemia peripheral arterial tonometry (RH-PAT) method.
RESUMEN
Background. In acute myocardial infarction, thrombus aspiration prior to percutaneous coronary interventions (PCI) is often beneficial, but this approach has never been studied in patients without acute myocardial infarction. The aim of this retrospective study is to shed light on that topic based on our initial experience with manual thrombus aspiration in patients with stable or unstable angina pectoris and angiographic evidence of lesion-site thrombus. Methods. We assessed the feasibility (thrombus aspiration without predilatation) of this approach; in addition, we determined angiographic coronary flow and myocardial blush grade. Results. During 33 months in which a total of 4725 PCI were performed in our centre, manual thrombus aspiration was attempted in 14 patients with stable or unstable angina pectoris with angiographic evidence of thrombus. In nine of these 14 patients, the aspiration catheter could be advanced into the lesion without predilatation; in eight patients visible thrombus was obtained. The corrected TIMI frame count improved during the entire interventional procedure (21.1±11.2 vs. 12.8±5.9 frames; p=0.015). Myocardial blush grade, which overall improved during PCI (p<0.001), tended to show greater improvement in patients in whom thrombus aspiration could be achieved (1.6±0.9 vs. 0.7±0.5; p=0.06). Conclusions. Preliminary evidence suggests that manual thrombus aspiration may occasionally be considered in selected patients without acute myocardial infarction but with angiographic evidence of lesion-site thrombus. Nevertheless, prospective studies are required to clearly define the role of this approach in clinical practice. (Neth Heart J 2010;18:423-9.).
RESUMEN
Background. New-generation drug-eluting stents (DES) may solve several problems encountered with first-generation DES, but there is a lack of prospective head-to-head comparisons between new-generation DES. In addition, the outcome of regulatory trials may not perfectly reflect the outcome in 'real world' patients.Objectives. To compare the efficacy and safety of two new-generation DES in a 'real world' patient population.Methods. A prospective, randomised, single-blinded clinical trial to evaluate clinical outcome after Endeavor Resolute vs. Xience V stent implantation. The primary endpoint is target vessel failure at one-year follow-up. In addition, the study comprises a two-year and an open-label five-year follow-up. (Neth Heart J 2010;18:360-4.).
RESUMEN
OBJECTIVES: To infer the relative impact of elevated triglyceride levels and insulin resistance on endothelial dysfunction in patients with chronic hypertriglyceridemia (HTG). METHODS: Endothelial function was studied in 11 HTG patients and 16 normolipidemic controls. Cumulative-dose infusions of 5-hydroxytryptamine (5HT) and sodium nitroprusside were infused locally into the brachial artery to study endothelium-dependent and endothelium-independent vasodilation, respectively. Data of the HTG patients were dichotomized around the median of insulin resistance, calculated as HOMA-index, forming HTG groups with mild (HTG-MIR) and severe insulin resistance (HTG-SIR). RESULTS: HTG patients had higher triglyceride levels and smaller LDL particle size than controls (both P< or =0.001), whereas these parameters did not differ between both HTG groups. Insulin resistance was higher in both HTG groups than in controls (11.1 (7.0-14.5) and 4.9 (4.0-6.7) vs. 2.4 (4.9-5.2), respectively, both P<0.001). Similarly, free fatty acid levels, another indicator of insulin resistance, were highest in the HTG-SIR group, followed by those in the HTG-MIR and control group (0.7 (0.6-0.8), 0.5 (0.4-0.6) and 0.4 (0.3-0.4) mmol/l, respectively, all P<0.05). Endothelial-dependent vasodilation was similar in HTG-MIR and controls. In contrast, the response to 5HT was attenuated in the HTG-SIR group compared to controls (low and high dose by, respectively, -60 and -44%, both P<0.01), and tended to be lower than in the HTG-MIR group (-43%, P=0.068 and -41%, P=0.100, respectively). Endothelium-independent vasodilation did not differ between the three groups. CONCLUSION: These findings indicate that chronic hypertriglyceridemia per se is not associated with endothelial dysfunction. In contrast, the presence of insulin resistance, characterized by hyperinsulinemia and FFA elevation, contributes to the induction of endothelial dysfunction in chronic HTG.