There is currently substantial confusion between the conceptual definition of the metabolic syndrome and the clinical screening parameters and cut-off values proposed by various organizations (NCEP-ATP III, IDF, WHO, etc) to identify individuals with the metabolic syndrome. Although it is clear that in vivo insulin resistance is a key abnormality associated with an atherogenic, prothrombotic, and inflammatory profile which has been named by some the “metabolic syndrome” or by others “syndrome X” or “insulin resistance syndrome”, it is more and more recognized that the most prevalent form of this constellation of metabolic abnormalities linked to insulin resistance is found in patients with abdominal obesity, especially with an excess of intra-abdominal or visceral adipose tissue. We have previously proposed that visceral obesity may represent a clinical intermediate phenotype reflecting the relative inability of subcutaneous adipose tissue to act as a protective metabolic sink for the clearance and storage of the extra energy derived from dietary triglycerides, leading to ectopic fat deposition in visceral adipose depots, skeletal muscle, liver, heart, etc. Thus, visceral obesity may partly be a marker of a dysmetabolic state and partly a cause of the metabolic syndrome. Although waist circumference is a better marker of abdominal fat accumulation than the body mass index, an elevated waistline alone is not sufficient to diagnose visceral obesity and we have proposed that an elevated fasting triglyceride concentration could represent, when waist circumference is increased, a simple clinical marker of excess visceral/ectopic fat. Finally, a clinical diagnosis of visceral obesity, insulin resistance, or of the metabolic syndrome is not sufficient to assess global risk of cardiovascular disease. To achieve this goal, physicians should first pay attention to the classical risk factors while also considering the additional risk resulting from the presence of abdominal obesity and the metabolic syndrome, such global risk being defined as cardiometabolic risk.
Calcific aortic stenosis (AS), the most prevalent heart valve disorder in developed countries,, is characterized by progressive fibro-calcific remodelling and thickening of the aortic valve leaflets that evolve over years to cause severe obstruction to cardiac outflow. In developed countries, AS is the second-most frequent cardiovascular disease after coronary artery disease and systemic arterial hypertension with a prevalence of 0.4% in the general population and 1.7% in the population >65 years old. Congenital abnormality (bicuspid valve) and older age are powerful risk factors for calcific AS. Metabolic syndrome and an elevated plasma level of lipoprotein(a) have also been associated with increased risk of calcific AS. The pathobiology of calcific AS is complex and involves genetic factors, lipoprotein deposition and oxidation, chronic inflammation, osteoblastic transition of cardiac valve interstitial cells and active leaflet calcification Although no pharmacotherapy has proven to be effective in reducing the progression of AS, promising therapeutic targets include lipoprotein(a), the renin-angiotensin system, tumor necrosis factor ligand superfamily member 11 (also called receptor activator of NF-κB ligand (RANKL)) and ectonucleotidases. Currently, aortic valve replacement (AVR) remains the only effective treatment for severe AS. The diagnosis and staging of AS are based on the assessment of stenosis severity and left ventricular systolic function by Doppler echocardiography and the presence of symptoms. The introduction of transcatheter AVR in the past decade has been a transformative innovation for patients at high or extreme-high risk for surgical AVR and this new technology might extend to lower-risk patients in the near future.
Post-operative atrial fibrillation (POAF) is a frequent complication occurring in 30% to 50% of patients after cardiac surgery. It is associated with an increased risk of mortality and morbidity, predisposes patients to a higher risk of stroke, requires additional treatment, and increases the costs of the post-operative care. The aim of this review is to present the current state of knowledge about the risk factors, mechanisms, prevention, and treatment of this complication. In addition to the well known risk factors for the development of POAF such as age, left atrial enlargement, and valvular surgery, new metabolic risk factors related to visceral obesity have been identified. With regard to the prevention of POAF, beta-blocker drugs are effective and safe and can be used in most patients, whereas amiodarone can be added in high-risk patients. Biatrial pacing was shown to be effective; however, its complexity might limit its application. Although there are only few data regarding the usefulness of magnesium, statins, N-3 polyunsaturated fatty acids, and corticosteroids, their addition to beta-blocker drugs might be of benefit for further reducing POAF. Treatment includes the use of an AV nodal blocking agent to achieve the rate control. If AF does not spontaneously convert to sinus rhythm within 24 h, anticoagulation should be initiated and a rhythm control strategy should be attempted. More investigations are warranted to explore mechanisms by which POAF occurs. This new knowledge would undoubtedly translate into a more efficient prevention and treatment of this common post-operative complication that is associated with a major health and economic burden.
Elevated Lp(a) and OxPL-apoB levels are associated with faster AS progression and need for aortic valve replacement. These findings support the hypothesis that Lp(a) mediates AS progression through its associated OxPL and provide a rationale for randomized trials of Lp(a)-lowering and OxPL-apoB-lowering therapies in AS. (Aortic Stenosis Progression Observation: Measuring Effects of Rosuvastatin [ASTRONOMER]; NCT00800800).
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