Abstract 4864: Electrocardiographic and Angiographic Correlations in Patients With Left Bundle Branch Block With Suspected Myocardial Infarction Undergoing Urgent Coronary Angiography
Background: The purpose of this study is to determine the accuracy of the Sgarbosa criteria to identify the presence of acute Myocardial Infarction (MI) diagnosed by biomarkers and to predict coronary occlusions in patients with new or presumed new Left Bundle Branch Block (LBBB) and suspected acute MI.
Methods: We retrospectively reviewed the records of 1322 consecutive patients presenting to our institution with suspected acute transmural MI who underwent urgent coronary angiography between 2004 and 2008.
Results: Thirty four patients (2.6%) had LBBB. Results of Sgarbosa criteria versus presence of an occluded coronary artery and troponin status are shown in the table⇓ below.
Conclusions: In our cohort of patients 26 out of 34 (76%) patients had MI as determined by elevated tropnin levels. Sgarbosa criteria, when applied with the weighted score of >/=2, could detect patients of myocardial infarction with a sensitivity of 62%, specificity of 63%, positive predictive value of 76% and negative predictive value of 23%. When the same criteria were applied to detect occlusion of any coronary artery the sensitivity was found to be 50% with a specificity of 32%, positive predictive value of 29% and negative predictive value of 54%. In conclusion, the incidence of MI among the patients of new or presumed new LBBB is high at 76%. The overall usefulness of Sgarbosa criteria to diagnose MI and occluded coronaries (which are most likely to benefit from early revascularization) in patients with LBBB is moderate but the negative predictive value is very low. Hence patients with new or presumed new LBBB with suspected myocardial infarction should get the benefit of early catheterization if clinically justified.