Left Bundle Branch Blockade in Suspected Acute Myocardial Infarction

The diagnosis of acute myocardial infarction (AMI) in the setting of left bundle branch block of the Hiss left bundle branch block (LBBB) is challenging for the clinician. Despite current guidelines for therapy, early reperfusion may not be appropriate for all patients with new or suspected new BLNPG because only a minority are due to acute myocardial infarction with true arterial occlusion. Current guidelines recommend that patients with probable myocardial infarction (MI) who have a new or suspected new BLNPG should be considered diagnostic for AMI and should receive early reperfusion therapy. Despite this recommendation, early reperfusion may not be appropriate for all patients with new BLNPG because only a minority are diagnosed with myocardial infarction. The prevalence of false-positive catheterization laboratory activation is frequent among patients with BLNPG, and a significant proportion of patients with BLNPG with AMI do not have a blocked culprit artery at catheterization. Careful clinical evaluation is essential in the diagnosis and management of patients with acute MI and BLNPG. Avoiding unnecessary burdens and risks resulting from early reperfusion therapy can have a significant impact, especially in a center with limited modality options.