History

Introduction Left bundle branch block (LBBB) can occur when there is a delay in or a block of conduction at several locations in the intraventricular conduction system. These locations include the main left bundle branch or in each of its two major fascicles; the distal conduction system of the left ventricle; the fibers of the bundle of His, which develop into the main left bundle branch; or the ventricular myocardium. Aim Serum levels of malondialdehyde (MDA) and ceruloplasmin (Cp) will be evaluated to understand more about the process of oxidative stress and its relationship to LBBB. Material and methods: Seventy patients with LBBB were compared to a control group of seventy healthy individuals. Groups were compared based on their MDA and Cp levels. Results Patients with LBBB had significantly higher MDA levels than healthy controls (p < 0.05). Furthermore, the levels of MDA in the study group were significantly higher than those in the control group (p <0.0001). In addition, the LBBB group had a significantly greater concentration of ceruloplasmin (p< 0.0001). Conclusions High amounts of MDA were found in patients with LBBB, which may contribute to haematological degradation when exposed to free radicals. These findings support the idea that oxidative stress may play a role in the etiopathogenesis of LBBB by showing the presence of anbalance in the oxidant-antioxidant system.