Left bundle branch block (LBBB)-induced cardiomyopathy

Left bundle branch block (LBBB)-induced cardiomyopathy (CMP) is an increasingly recognized type of dilated CMP identified in a minority but not negligible proportion of patients with newly diagnosed heart failure. However, it has not yet been included among the possible etiologies of dilated CMPs or among the unclassified CMPs. Although a few sets of diagnostic criteria have been proposed, currently there is a lack of universal consensus regarding diagnostic criteria. Some specific clinical features and electrocardiography, echocardiography and cardiac magnetic resonance imaging findings are recommended to help physicians in the diagnosis of LBBB-induced CMP. In this review, prevalence, pathophysiological mechanisms, diagnostic criteria, diagnostic modalities and specific features of LBBB-induced CMP has been addressed with the attention to the differential diagnosis of other dilated CMPs.