News & Views in 2009

Pulmonary vein antrum isolation is an accepted alternative to antiarrhythmic therapy for restoring normal sinus rhythm in patients with atrial fibrillation. The procedure has a high initial success rate, but many patients subsequently experience recurrence of the arrhythmia. Cardiac magnetic resonance might offer a means of identifying patients who are more likely to experience successful long-term results from pulmonary vein antrum isolation.

The results of HF-ACTION—the largest ever intervention trial of a nonpharmacological treatment for chronic heart failure—have been reported. The investigators randomly allocated participants to either a structured exercise program or to usual care. Although the primary end point was not reached at the prespecified significance level, the background evidence and data from previous trials and other prespecified analyses compel me to conclude that exercise training should be recommended for patients with stable chronic heart failure.

Stroke risk in patients with nonvalvular atrial fibrillation increases markedly with age. Although anticoagulation is more effective than antiplatelet therapy in atrial fibrillation, it tends to be underutilized in the elderly. A study by van Walraven et al. examines the influence of age on stroke prevention therapy in atrial fibrillation.

The DIAD trial investigators have demonstrated that screening for inducible myocardial ischemia did not improve overall clinical outcome in a contemporary cohort of patients with asymptomatic type 2 diabetes, most of whom were receiving excellent medical management and few of whom underwent revascularization. Future studies should be designed to evaluate the clinical value and cost effectiveness of unconditional treatment versus screening using techniques to detect atherosclerotic and ischemic burden, coupled with therapeutic interventions, risk-factor management, and selective use of revascularization in high-risk patients.

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is challenging to diagnose because of nonspecific findings, particularly in the early phases of the disease. Clinical diagnosis is made on the basis of several criteria, but these lack sensitivity. Asimaki et al. suggest that immunohistochemical analysis of myocardial desmosomal proteins is a highly sensitive and specific diagnostic test for ARVD/C.

The novel risk score for new-onset atrial fibrillation proposed by Schnabel et al. is based on readily identifiable risk factors and provides an excellent 'first draft' to focus primary prevention and halt the pandemic spread of this arrhythmia and its potentially lethal consequences. The risk score does, however, require further validation and sophistication with novel imaging techniques before it can be applied in clinical practice.

Dual antiplatelet therapy with aspirin and clopidogrel is effective in limiting adverse coronary thromboischemic events in most patients undergoing coronary stenting. However, platelet reactivity to clopidogrel is variable and stent thrombosis can occur suddenly and unexpectedly in up to 3% of patients. Is responsiveness to clopidogrel an indicator of risk of post-treatment thromboischemic events?

There is notable variation in incidence, presentation, risk factors, and prognosis for strokes occurring in children. At present, there is no stroke classification system specifically tailored to the multiple risk factors and etiologies of pediatric stroke. The study by the International Pediatric Stroke Study investigators on predictors of cerebral arteriopathy in children with arterial ischemic stroke deserves special attention in planning secondary stroke prevention strategies in this population of patients.

Should patients with high-risk coronary artery disease be treated with CABG or receive drug-eluting stents? The SYNTAX trial aimed to define the optimal revascularization strategy for patients with previously untreated three-vessel and/or left main coronary artery disease.

Proton-pump inhibitors (PPIs) can alter the pharmacodynamic profile of clopidogrel and reduce its platelet-inhibitory effects. Ho and colleagues have reported that concurrent use of PPIs and clopidogrel leads to in an increase in adverse cardiovascular outcomes. In this article we discuss the clinical implications of the interaction between these two drugs.

The ASSOCIATE study investigators have reported that the I_f current inhibitor, ivabradine, is safe, improves exercise performance, and delays the development of ischemia in patients with chronic stable angina being treated with atenolol. Ivabradine should be considered in the medical management of symptom-limited patients with angina, when heart rate is suboptimally controlled.

The A4 and other similar (small) studies strongly support the launch of major trials of left atrial catheter ablation for the maintenance of sinus rhythm, reduction of cardiovascular hospitalizations and improved survival in patients with symptomatic recurrent atrial fibrillation. Will pharmacological therapies continue to have an important place in the management of atrial fibrillation?

The benefits of clopidogrel in the treatment and prevention of coronary artery disease vary among patients. Studies have identified predictive markers of poor response to clopidogrel that might allow risk stratification of patients. Are we ready to enter the age of personalized medicine?

Management of asymptomatic patients with severe mitral valve regurgitation is controversial—conservative surveillance and early mitral valve repair have both been advocated as reasonable approaches on the basis of divergent data. A new study by Kang et al. fuels this debate. However, careful assessment of the existing literature can provide insight into the optimal care of this population of patients.

The cardiovascular community has witnessed an important transition over the past two decades—from awareness of the global nature of the cardiovascular disease epidemic, to identification of interventions to control it, and now to a resolution that global action is urgently required.

An effective risk score for patients undergoing coronary angioplasty is yet to be established. In this article we discuss the merits of using the EuroSCORE risk model for assessing these patients, and propose a potential modification to the system.

Two or more drugs are needed to control blood pressure in the majority of patients with hypertension. The most commonly used combinations include a diuretic; however, results of two large, controlled trials show that better cardiovascular protection is provided by a combination of a renin-angiotensin inhibitor and a long-acting calcium-channel blocker than combinations that include a diuretic.

Poor responders to clopidogrel have low levels of circulating active metabolite. However, in vitro experiments have shown that blood platelets from poor responders are fully inhibited by the active metabolite of this prodrug. Impaired platelet inhibition reflects inadequate plasma levels of active metabolites, and not differences in platelet P2Y₁₂ receptor function.

Magnetic Resonance Spectroscopy is a novel research tool used to noninvasively quantify myocardial triglyceride content. This method provides the opportunity to study myocardial steatosis in patients with diabetes.