Reviews & Analysis

A single definition for the metabolic syndrome is not forthcoming since discussion of its forms and causes is continuing. Genetic causes and onset of the syndrome in relation to triggering genetic–environment interactions have been suggested. In this Review, the currently available knowledge about the most common purported genetic causes is drawn together.

In healthy adult hearts approximately 70% of energy is obtained from fatty acids; the balance comes from lactate, pyruvate and ketones. The pattern of substrate use is altered in failing hearts. This Review discusses substrate use and the possible benefits of using metabolic agents to cause a shift away from fatty acids as the main substrate.

The severity of left ventricular dilatation and remodeling represents one of the strongest predictors of mortality. Prevention, reversal, or both of left ventricular remodeling therefore constitute crucial parts of therapy in many cases. Along with pharmacologic therapies various surgical procedures are available. In this Review, the most common surgical options for left ventricular remodeling are discussed.

In the no-reflow phenomenon, blood flow to an infarcted area can be markedly reduced by destruction of the microvasculature or blockage of vessels by microemboli, despite an open infarct-related artery. Minimization of the affected area is important to improve outcomes. Data are presented in this Review on causes and therapies.

Major bleeding is the most common noncardiac complication after percutaneous coronary intervention for coronary artery disease. The reduction of vascular access site complications in PCI procedures is, therefore, a critical challenge. In this month's Viewpoint, Martial Hamon discusses why an alternative access site is needed and compares the benefits of the transradial approach with those of the femoral approach.

Despite LDL-cholesterol targets being lowered several times in recent years, are they low enough? New data continue to be published showing that LDL lowering should be a primary target of therapy, with the possibility of simultaneously raising HDL cholesterol. Wiviott and Cannon bring together the extensive data to provide an update.

Many protein kinases are positioned proximal to critical proteins that mediate cell function. Since these functions can be altered by disease, attention has turned to protein kinases as therapeutic targets. In this Review, the role of protein kinases in myocardial disease, and the pharmacologic therapy possibilities they present are discussed.

In this Review, Amish Desai, Cindy Fuller, Jill Jesurum and Mark Reisman discuss the possible link between patent foramen ovale and cryptogenic stroke, treatment options for prevention of paradoxical embolism related to patent foramen ovale and the controversial association between patent foramen ovale and migraine headaches.

Major advances have been seen both in the development and design of left ventricular assist devices. As a result, the indications for use have increased substantially. In this month's Viewpoint, Jonathan Chen, Yoshifumi Naka and Eric Rose explore the clinical promise and the current technical barriers of widespread application of left ventricular assist devices as destination therapy.

Although mechanical circulatory support has been used in children for many years, the development of implantable devices and improvements in extracorporeal support have provided viable options for bridging to transplantation or even to recovery. Hetzer and Stiller share their experience with the technology and techniques and discuss the decision-making processes.

Clopidogrel is widely used during percutaneous coronary intervention and to treat acute coronary syndromes. Nonresponsiveness and variability in responsiveness to clopidogrel therapy have been noted in numerous studies, and could put some patients at risk of repeat thrombotic events. The possible mechanisms and ways to overcome poor response to clopidogrel are discussed here.

Since the ventricles share a common septum, interaction between them is inevitable. Performance of each ventricle is influenced by the compliance, filling volume and pressure of the other, as well as by external constraints from the pericardium. In this review, the role of direct diastolic ventricular interaction is explored in various cardiovascular disorders.

A huge body of evidence now supports aggressive LDL cholesterol lowering to reduce cardiovascular risk, but what LDL cholesterol target level should be recommended? Here, Philip Barter and Kerry-Anne Rye examine the safety issues associated with achieving very low levels of LDL cholesterol and whether it is feasible to achieve very low levels in all high-risk people.

Despite imaging advances, diagnosis of infective endocarditis is not simple, and uncertainty about whether a surgical or nonsurgical approach is best and the timing of intervention can hamper therapy. In this Review, Saptarsi Haldar and Patrick O'Gara discuss the major features of diagnosis and therapy and make recommendations based on the available data.

Improvement is still needed in the diagnosis of renal artery stenosis, which is the most common treatable cause of secondary hypertension. An accurate functional and morphological characterization of the disease might assist in management of patients. The value of magnetic resonance angiography in this setting is discussed.

More than 80% of the US elderly population dies from coronary heart disease, but the benefits of statin therapy are not realized. These drugs are frequently underprescribed to elderly patients because few relevant age-specific data are available. This Review draws together the findings from major studies and assesses the value of statin use in the elderly.