Neurohumoral Markers of Cardiac Autonomic Denervation After Surgical Ablation of Long- Standing Persistent Atrial Fibrillation

Background: . The autonomic nervous system (ANS) plays an important role in modulation of cardiac electrophysiology and arrhythmogenesis. Disorders of the ANS components can be a prognostic factor of an unfavorable course of cardiovascular diseases. The aim of the study was to evaluate the association between efficacy of radiofrequency (RF) surgical ablation of long-standing persistent atrial fibrillation (AF) and neurohumoral transmitter levels as well as correlation between these data with myocardial iodine-123-metaiodobenzylguanidine ( 123 I-MIBG) uptake. Methods: . Two groups of patients with acquired valvular heart disease were compared: patients with surgical AF ablation and patients with sinus rhythm. Results: . The decrease of norepinephrine (NE) level in coronary sinus has a direct association with the heart-to-mediastinum ratio (p=0.02) and negative correlation with 123 I-MIBG uptake defect (p=0.01). NE level decreased significantly after the main stage of surgery, both in patients with AF (p=0.0098) and sinus rhythm (p=0.0039). Furthermore, the significance (p=0.001) of the aortic root and coronary sinus gradient of NE level 0.405 pg/mL was determined as a cut-off value for efficacy evaluation of the RF denervation. Conclusion: . The practical significance of the obtained results lies in the possibility of using the technique to predict the efficacy of the ‘Maze-IV’ procedure, which will allow assessing the risk of AF recurrence after ablation.