Comparison of cobalt - albumin binding assay to echocardiogram in the diagnosis of patients with chest pain

Cardiovascular disease is the leading cause of mortality in developed countries andplaces a massive burden on healthcare services. Thousands of patients visit every yearthe Emergency Department (ED) with acute chest pain and a considerable proportionhas an acute coronary syndrome (ACS). In most cases, the electrocardiogram and thecommonly used biomarkers are not helpful in the early diagnosis of myocardialischemia.ObjectiveTo assess the role of ischemia modified albumin (IMA), a novel cardiac biomarker, inexcluding unstable angina (UA) in patients visiting the ED with acute chest pain. Thepredictive value of serum IMA concentrations were evaluated in comparison toechocardiogram.MethodsWe studied 33 patients (84.8% males, age 59.8±10.8 years) who presented at theAccident and Emergency Department with acute chest pain lasting < 3 h, normal ornon-diagnostic electrocardiogram and normal serum troponin and CK-MB levels.Serum IMA levels were determined and a comprehensive echocardiographic studywas performed. All patients were admitted to our Department of Cardiology and thediagnosis of UA was established with exercise or thallium stress test or with coronaryangiography.ResultsFive patients were eventually diagnosed with UA. The area under the curve for thediagnosis of unstable angina based on serum IMA levels was 0.193 (95% confidenceinterval 0.047-0.339, p < 0.05). Serum IMA levels ≥ 31,95 IU/ml had a sensitivity,specificity, positive and negative predictive value for the diagnosis of UA of 40.0%,28.6%, 9.1% and 72.7%, respectively. The sensitivity, specificity, positive andnegative predictive value of echocardiography for the diagnosis of UA was 60.0%,89.3%, 50.0% and 92.6%, respectively.Conclusion: Assessment of serum IMA levels in patients presenting with suspectedUA has comparable negative predictive value with echocardiography for excludingthe diagnosis of UA. Therefore, this biomarker appears to be useful in the diagnosisand stratification of risk in patients with ACS