Signaling Pathways (TNF-α-NF-κB, TLR2-TLR4 as well as ROS-MDA) and Cardiac Damages during Cardiac Surgeries (Coronary stenting, Permanent Pacemaker Implantations, Radiofrequency Ablations).

Introduction: The mutual activations of multiple signaling pathways are the key factors in the development and progression of myocardial cell injuries.

Objective: This research aimed to compare the different degrees of myocardial injury after coronary stenting, permanent pacemaker implantations, or cardiac radiofrequency ablation and to investigate the effects of the mutual activation of TNF-α/NF-κB, TLR2/TLR4, and ROS/MDA signaling pathways on myocardial injury in elderly patients after coronary stents or permanent pacemakers or radiofrequency ablation.

Methods: We determined reactive oxygen species (ROS), malondialdehyde (MDA), toll-like receptor 2 (TLR2), toll-like receptor 4 (TLR4), nuclear factor kappa B (NF-κB), tumor necrosis factor- α (TNF-α) and high-sensitive cardiac troponin T (hs-cTnT) as a marker of myocardial injury in patients.

Results: The levels of ROS, MDA, TLR2, TLR4, NF-κB, TNF-α, and hs-cTnT were increased in patients with permanent pacemaker implantations when compared to patients with cardiac radiofrequency ablation (P < 0.01) at 6 months and were further increased in patients with coronary stenting compared to patients with cardiac radiofrequency ablation and permanent pacemaker implantations at 6 months, respectively (P < 0.01). This research confirmed that ROS, MDA, TLR2, TLR4, NF-κB, and TNF-α predicted myocardial injury severity.

Conclusion: Oxidative stress (ROS/MDA signaling pathway) may be linked to immune response (TLR2/TLR4 signaling pathway) and pro-inflammatory response (TNF-α/NF-κB signaling pathway) in myocardial injury, and ROS/MDA signaling may play a dominant role.