Abstract 17087: VNS Induced Early Suppression of the Excessive Inflammatory Response May Contribute to its Beneficial Effects on Chronic Heart Failure

Background: The inflammatory response plays a pivotal role in the pathogenesis of chronic heart failure (CHF). Although vagal nerve stimulation (VNS) improves CHF, the central mechanism remains unclear. Since VNS exerts powerful anti-inflammatory effects, we investigated how VNS impacts on the inflammatory regulation and the development of CHF. Methods: In 8 weeks old Sprague-Dawley rats, we created large myocardial infarction (MI) and started VNS 2 weeks after MI. We adjusted the intensity of VNS below the threshold of bradycardia (20 Hz, 1.5±0.9 volts, 10 sec on, 50 sec off). In the first group (EARLY) (CHF: n=8, VNS: n=13), we continued VNS for 3 days and evaluated the early impact of VNS on inflammation on the 3rd day. In the second group (LATE) (CHF: n=13, VNS: n=13), we continued VNS for 4 weeks and evaluated cardiac remodeling and function on the last day. Results: In EARLY, hemodynamic parameters or plasma BNP as an index of CHF did not change significantly. In contrast, VNS halved the invasion of...