Regarding myoglobin's clinical utility, which statement is correct?

The correct statement emphasizes that myoglobin levels below 100 µg/L upon admission can help in excluding an acute myocardial infarction (AMI). Myoglobin is an early biomarker released into the bloodstream when muscle cells, including cardiac muscle, are damaged. Its rapid release means that low levels can indicate that significant cardiac damage has not occurred, thereby serving as a useful exclusion criterion for AMI.

When myoglobin levels are low at the time of presentation, it suggests that, despite the patient’s symptoms, there is no significant muscle damage, which decreases the likelihood of AMI. In clinical practice, using myoglobin in this way aids in making timely decisions about further diagnostic testing and management for potentially life-threatening conditions such as AMI.

In clinical evaluation, other factors must be taken into account, and myoglobin is often used in conjunction with other biomarkers such as cardiac troponins and clinical assessments.