Left bundle branch block and myocardial infarction, a diagnosis not always easy: Our experience and review of literature

Angela Sansone, Francesca Bonura, Fabiana Castellano, Rosanna Iacona, Dario Mancuso, Giuseppina Novo, Pasquale Assennato, Salvatore Novo

Department of Internal Medicine, Cardiovascular and Nephro-Urological Disease, Unit of Cardiology, University of Studies “P. Gi-accone” Palermo, Palermo, Italy.

DOI: 10.4236/wjcd.2012.22014                

Abstract

The occurrence of left bundle branch block (LBBB) is quite common in clinical practice. The changes in cardiac repolarization, caused by this disorder of electric conduction, may mask the presence of an acute myocardial infarction (AMI), delaying the diagnostic-therapeutic iter, with an important impact on prognosis. We describe the case of a woman of 59 years with LBBB, came to our observation for a constrictive chest pain associated with dyspnea. The diagnostic workup for suspected acute coronary syndrome (ACS), initially conducted only on the analysis of the electrocardiogram (negative TnI at entry), showed the presence of coronary arteries free of stenosis. However, the diagnostic confirmation of AMI was completed after the rise of cardiac markers and the electrocardiographic changes. This case confirm the difficulty about the diagnosis of AMI in patients with LBBB and stresses, however, as the use of some criteria proposed in the literature [1-3] can guide to its identification, directing patient to an appropriate treatment.

Keywords

Left Bundle Branch Block (LBBB); Myocardial Infarction; Electrocardiogram.

Conflicts of Interest

The authors declare no conflicts of interest.

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