Circulating serum adiponectin levels in patients with coronary artery disease: relationship to atherosclerotic burden and cardiac function.

BACKGROUND: Abnormal adipocyte function is implicated in both the pathophysiology of coronary heart disease (CHD) and cardiac function, where adiponectin provides a putative link. However, the utility of adiponectin as a discriminator of CHD severity is unclear and may be confounded by cardiac function. We hypothesized that plasma adiponectin would relate to indices of coronary artery disease severity (coronary atheroma scores, CAS), ejection fraction (EF) and regional wall motion abnormalities (RWMA) therein. METHOD: We measured adiponectin using a cross-sectional approach, we measured plasma adiponectin enzyme-linked immunosorbent assay in 204 consecutive patients (aged 34-81 years) undergoing elective coronary angiography. RESULTS: Levels of adiponectin decreased in an ordinal fashion across tertiles of increasing CAS (P = 0.047), but were nonsignificantly correlated to absolute values of CAS (P = 0.06). Adiponectin levels were unrelated to left ventricular dysfunction related measures of RWMA or EF. On multivariate analysis, (including factors relating to CHD risk, history and medication) adiponectin levels were independently inversely associated with triglycerides (P = 0.001), CAS tertiles (P = 0.01) and positively with age (P < 0.001). CONCLUSION: Levels of adiponectin decreased with coronary artery disease severity, without impact from systolic dysfunction, but levels may be moderated through established CHD risk factors such as smoking and triglycerides. Further work is warranted as to the clinical prognostic utility of this marker amongst CHD patients.

Platelet and leukocyte activation, atherosclerosis and inflammation in European and South Asian men.

BACKGROUND: Increased platelet activation occurs in ischemic heart disease (IHD), but increased platelet activation is also seen in cerebrovascular atherosclerosis and peripheral artery disease. It is not clear therefore whether platelet activation is an indicator of IHD or a marker of generalized atherosclerosis and inflammation. South Asian subjects are at high risk of IHD, but little is known regarding differences in platelet and leukocyte function between European and South Asian subjects. METHODS: Fifty-four male subjects (age 49-79 years) had coronary artery calcification measured by multislice computed tomography (CT), aortic atherosclerosis assessed by measurement of carotid-femoral pulse wave velocity (aortic PWV), and femoral and carotid atherosclerosis measured by B-mode ultrasound. Platelet and leukocyte activation was assessed by flow cytometry of platelet-monocyte complexes (PMC), platelet expression of PAC-1 binding site and CD62P, and expression of L-selectin on leukocytes. RESULTS: Elevated circulating PMC correlated significantly with elevated aortic PWV and PMC were higher in subjects with femoral plaques. In contrast PMC did not differ by increasing coronary artery calcification category or presence of carotid plaques. Higher numbers of PMC were independently related to elevated levels of C-reactive protein (CRP), higher aortic PWV, hypertension and smoking in a multivariate model. Markers of platelet and leukocyte activation did not differ significantly by ethnicity. CONCLUSIONS: Increased PMC are related to the extent of aortic and femoral atherosclerosis rather than coronary or carotid atherosclerosis. The association between elevated CRP and increased PMC suggests that inflammation in relation to generalized atherosclerosis may play an important role in PMC activation.

Antithrombotic therapy in patients with chronic heart failure: rationale, clinical evidence and practical implications.

Chronic heart failure (CHF) is traditionally associated with increased risk of thromboembolic complications. Key features of CHF pathophysiology, such as impairment of intracardiac hemodynamics, peripheral blood flow deceleration, neuroendocrine activation, chronic oxidative stress and proinflammatory changes, could explain the predisposition to thromboembolism. However, conclusive epidemiologic data on thromboembolic event incidence in CHF are lacking. Furthermore, the place of antithrombotic therapy in CHF management is still uncertain. Apart from established indications for warfarin (e.g. atrial fibrillation and previous embolic events), there is no robust evidence to support administration of vitamin K antagonists to other patients with CHF, particularly to patients in sinus rhythm. The role of aspirin in preventing thromboembolism in these patients is also controversial. Large randomized trial data on the effectiveness and risks of warfarin and aspirin use in CHF patients with sinus rhythm are forthcoming. This article provides a brief overview of the epidemiologic and pathobiological background of thromboembolism in CHF, and discusses the up-to-date clinical evidence on antithrombotic therapy in detail.

Low molecular weight heparins in cardiovascular medicine.

Cardiovascular diseases are the major cause of morbidity and mortality in the Western countries and their prevalence is increasing in developing world. The final biological evolution of atherosclerotic process, supporting development and progression of cardiovascular diseases, is thrombosis. In the most recent years several clinical trails have established that low molecular weight heparins play a major role in the area of prevention and treatment of arterial and venous thrombosis. It is now established, that low molecular weight heparins are efficacious and safe anticoagulant options for patients with deep vein thrombosis, pulmonary embolism, unstable angina and non-ST-segment elevation myocardial infarction. In addition, low molecular weight heparins play a major role to prevent thromboembolic events in patients with chronic diseases (e.g. due to cerebrovascular ischemic events, cancer) and in patients undergoing surgical interventions. Clinical trials have also shown that low molecular weight heparins might play a role in the treatment of patients with ST-segment elevation acute myocardial infarction, in the prevention of thrombotic events in patients with congestive heart failure, and in patients undergoing percutaneous coronary interventions. The combined use of low molecular weight heparins with fibrinolysis and other antithrombotic agents has been also studies in a number of clinical trials. This review summarises the results of the most recent clinical studies regarding the use of low molecular weight heparins in prevention and treatment of cardiovascular diseases.