Reviews & Analysis

The introduction of a new high-sensitivity troponin immunoassay might revolutionize the way acute coronary syndrome is diagnosed. The high analytical sensitivity of the assay enables earlier and more accurate identification of myocardial injury than with currently used methods, and also allows for the safe discharge of patients without myocardial ischaemia.

Coronary revascularization has a prominent role in the management of chronic, stable coronary artery disease, but decision-making guided by angiography alone for identifying haemodynamically relevant lesions can be challenging. The DEFER study now demonstrates favourable 15-year outcomes after deferral of revascularization in angiographically relevant, but functionally nonsignificant, coronary lesions.

The results of the first randomized, controlled trial to assess adaptive servo-ventilation (ASV) for central sleep apnoea were expected to confirm the positive findings from previous observational studies and meta-analyses. However, ASV did not have the expected beneficial effects for patients with heart failure and reduced ejection fraction.

Among patients with diabetes mellitus and ischaemic heart disease, high-sensitivity testing effectively identified 39.3% of patients with elevated troponin levels who were at high 5-year risk of cardiovascular death, myocardial infarction, or stroke. Compared with optimal medical therapy, revascularization did not reduce ischaemic events among patients with elevated troponin levels.

A new systematic review and meta-analysis by Lee and colleagues confirms the safety of nonprimary percutaneous coronary intervention (PCI) at centres without onsite surgical backup. In daily clinical practice at PCI centres without onsite surgical facilities, quality assurance and improvement programmes are important to ensure high-quality care.

Sudden cardiac death in elderly patients with recent myocardial infarction and reduced left ventricular ejection fraction can be substantially reduced using implantable cardioverter–defibrillators (ICDs) in appropriately selected, high-risk cardiac patients. Increased use of ICD therapy among eligible elderly patients will save lives.

Regulatory approval of high-risk cardiovascular devices is on the basis of clinical studies submitted with a premarket approval application. Failure to publish many of these studies in peer-reviewed literature, and major discrepancies between premarket approval submissions and those studies that are published, raise important questions for clinicians and other stakeholders.

The Wells rule is the most widely used pretest clinical probability score for patients with suspected deep-vein thrombosis. However, the rule was developed and validated in the outpatient setting, and its accuracy in hospitalized patients has not been investigated previously. A new study indicates that this rule should not be used in the inpatient setting.

Uncertainty surrounds the benefit of preventive pharmacological therapies in reducing aortic disease in patients with Marfan syndrome. The Marfan Sartan trial now suggests that losartan is not beneficial in reducing the rate of aortic dilatation—the precursor of dissections and premature death in Marfan syndrome.

Intra-aortic balloon pumping has recently been shown to be ineffective in treating cardiogenic shock due to myocardial infarction. Other, more potent percutaneous pumps have been developed, and their use is growing substantially, but they have not been studied in randomized trials. Two new reports provide provocative information about these devices.

Dual antiplatelet therapy is the cornerstone of treatment after drug-eluting stent implantation. Although treatment for 12 months is the standard of care in many parts of the world, the optimal duration of treatment is still being determined. Meta-analysis data now suggest that shorter or longer durations might yield preferred outcomes in different patient subgroups.

Meta-analyses and large population-based studies have linked shorter body height with increased risk of coronary heart disease (CHD). This complex association is now confirmed at the gene level, indicating that genetic variants affecting body height and associated with short stature seem to have independent roles as risk factors for CHD.

Women—especially younger women—have greater morbidity and mortality from myocardial infarction than men. The VIRGO study involving young patients (aged 18–55 years) suggests that delay in arrival to hospital and suboptimal management occurs more commonly in young women than men. Female sex was an independent predictor of delay.

Two types of genetic risk scores (GRS) have been devised to identify patients who will benefit most from cardiovascular-drug treatment: one related to the intermediate phenotype within a causal pathway, and another related to the expected clinical event. These GRS are promising and might have clinical implications for future practice.

The precise physiological mechanisms linking cigarette smoking with increased coronary risk remain largely speculative. Similarly, the reason why smoking cessation is effective at ameliorating this risk is also unclear. The subclinical study by Nakanishi and colleagues has challenged the orthodoxy that plaque formation is the necessary ingredient underpinning these associations.

Strong associations exist between sleep disordered breathing (SDB) and both atrial fibrillation (AF) and heart failure (HF). Burgeoning epidemics of obesity, SDB, AF, and HF make these conditions priorities for health-care policymakers. Two observational studies now suggest outcome benefits from screening and treating for SDB in AF and HF.

The ROX CONTROL HTN study demonstrated the efficacy of arteriovenous coupler therapy in patients with resistant hypertension. However, one-third of the patients developed late ipsilateral venous stenosis, which required venoplasty or stenting. Future research is needed to identify the risk–benefit ratio of this new approach.

The perioperative management of patients with atrial fibrillation who require an elective surgical or other invasive procedure is an area of ongoing uncertainty. Accumulating evidence from observational studies suggests that the use of bridging anticoagulation with heparin, although well-intentioned, might not reduce perioperative thromboembolism and can increase bleeding.