Interpreting Troponin Tests: Coming to a New Consensus

Interpreting Troponin Tests: Coming to a New Consensus

Since its introduction in the early 1990s, cardiac troponin testing has been predominantly used to diagnose or rule out myocardial infarction (MI) in patients with possible symptoms of MI. However, it has become clear that a positive troponin indicates that cardiac injury has occurred, but it is not specific for the etiology of the injury. “Experience with troponin testing has also showed that higher levels identify patients at greater risk for adverse events, regardless of the clinical setting (eg, MI, heart failure, or non-cardiac etiologies),” explains L. Kristin Newby, MD, MHS, FACC, FAHA. “However, more recent studies have raised questions about cardiac troponin cutoffs that should be used for diagnostic and prognostic interpretations and the particular importance of the clinical context in making those interpretations.” In the Journal of the American College of Cardiology, Dr. Newby and colleagues from seven professional societies, led by the American College of Cardiology, released a consensus statement to help clinicians determine when to order troponin testing and how to interpret results. The document provides a framework for clinicians to interpret results of troponin testing in a useful mechanism-based construct. Key Recommendations on Troponin Testing According to the consensus statement, physicians should adopt the definition of MI that was recently updated in order to fully understand the implications of elevated troponin levels. “The universal definition of MI, which was updated in 2012, is important because it provides a standard framework in which to apply troponin testing for a diagnosis of MI and emphasizes not only troponin levels, but also the importance of clinical symptoms of MI,” Dr. Newby says. In addition, the consensus statement...

Updated Guidelines: Primary Stroke Prevention

In the February 1, 2011 issue of Stroke, the American Heart Association/American Stroke Association (AHA/ASA) released new guidelines for the primary prevention of stroke. The guideline reviews evidence on established and emerging risk factors for stroke. A significant change in these guidelines, which update a previous statement from 2006, is that clinicians are urged to address primary prevention of both ischemic and hemorrhagic stroke because the risk factors and prevention strategies for these events largely overlap. The critical role of a healthy lifestyle in the prevention of stroke is also emphasized. Areas of particular interest include emergency department (ED) screening, aspirin use among low-risk patients, asymptomatic carotid artery stenosis, and atrial fibrillation (AF), among other updates. ED screening for stroke risk represents an entirely new recommendation. Due to a lack of resources, there has been a surge in the number of people who receive care through the ED. This setting represents a unique opportunity to capture individuals at high risk of stroke and to offer information on smoking cessation programs, referrals for alcohol/drug abuse programs, screening for hypertension, and identification of AF. Aspirin Update A notable point in the AHA/ASA scientific statement is that aspirin is not recommended for preventing a first stroke in people at low risk or in those with diabetes or diabetes plus asymptomatic peripheral artery disease. Use of aspirin to prevent cardiovascular events—including but not limited to stroke—is recommended for those at sufficiently high risk. However, it’s important to weigh the risks, primarily bleeding, associated with treatment. Managing Asymptomatic Carotid Artery Stenosis Population screening for asymptomatic carotid artery stenosis is not recommended. An area that has...