Using a high-sensitivity cardiac troponin test ruled-in or ruled-out a heart attack in the first hour in more than three quarters of patients in the emergency department, according to research published in Archives of Internal Medicine. This would cut monitoring time and ensure immediate treatment for patients with heart attacks, which improves outcomes, and allow patients to be reassured and sent home quickly as "worried well," or investigated for other conditions.
The researchers from University Hospital in Basel, Switzerland, used the high-sensitivity cardiac troponin test to measure the levels of troponin before and after one hour in patients with acute chest pain, and created an algorithm based on the baseline levels and the changes in troponin. Of these 17% were "ruled-in" as having had an acute myocardial infarction (acute MI, or heart attack), 60% were "ruled out," and the remaining 23% remained under observation.
"The use of this algorithm seems to be safe, significantly shortens the time needed for rule-out and rule-in of AMI, and may obviate the need for prolonged monitoring and serial blood sampling in 3 of 4 patients with chest pain," the authors conclude.
Patients with symptoms of heart attacks take up around 10% of all emergency department consultations. Using this algorithm could allow more than 75% of these patients to be dealt with quickly, either admitted into the hospital or discharged, freeing up time to assess the patients with less clear-cut conditions.
In a commentary published alongside the paper, L. Kristin Newby of Duke University Medical Center writes that this study provides: "…an important step forward in application of hsTn [high-sensitivity troponin] as a tool for triage of ED patients with possible MI. However much work remains to develop the evidence to bring hsTn testing and the algorithms they have developed to use in clinical practice." Newby warns that multicomponent algorithms can be hard to remember for busy and pressured physicians, suggesting that they should be "provided electronically to physicians along with the algorithmic interpretation to allow systematic application in triage and treatment."