Abstract
BACKGROUND: Management of patients with a suspected ACS and LBBB is a challenge to the clinician. AIM: To detect the ability of IMA to exclude myocardial ischemia in suspected patients with ACS and LBBB. MATERIAL AND METHODS: A total of 68 patients with suspected ACS and LBBB (group I) and another twenty patients age and sex matched known to have LBBB with normal coronary angiography (group II) were included in this study and subjected to: routine laboratory tests, 12 lead ECG, echocardiography, and measurement of serum troponin I (TnI) and IMA (measured by ELISA). Diagnostic coronary angiography was performed on all patients and scored by severity and modified Gensini scores. RESULTS: IMA and TnI levels are significantly increased in group I compared to group II (P value <0.001). IMA with a cutoff value >95 could predict significant CAD (lesions >50%) with AUC of 0.923, sensitivity of 88%, specificity of 83.33%, PPV of 93.6%, NPV of 71.4% and accuracy 86.76%. Moreover, by using both simple and multiple logistic regression analyses IMA could also independently detect significant CAD. The combined use of IMA and TnI significantly improved the sensitivity and the negative predictive value to 98% and 90.9% respectively. CONCLUSION: There was a distinct advantage of measuring IMA in patients presenting to the emergency department with acute chest pain and LBBB to rule out a final diagnosis of ACS.