Poor baroreflex gain is a marker of heightened sympathetic activity post-tachycardia termination in humans.
We hypothesized that sympathetic nerve activity (SNA) remains elevated after tachycardia termination in patients with low baroreflex gain (BRG), and decreased to or below baseline in patients with high BRG. In a cohort of patients who participated in a previously published study [3], BRG, SNA, blood pressure, and central venous pressure were measured immediately after the termination of simulated tachycardia. While the hemodynamic responses following tachycardia termination were similar in both groups, SNA remained elevated in patients with low BRG compared to a decrease below baseline levels in patients with high BRG (p = 0.04). Increased sympathetic activity following tachycardia termination could be arrhythmogenic and might play a role in the genesis of recurrent ventricular arrhythmias following tachycardia termination.
Kowal
Robert C
RC
Division of Cardiology, Dept. of Internal Medicine, University of Texas, Southwestern Medical Center, Room C57.102, 5323 Harry Hines Blvd, Dallas, TX 75390-9047, USA.
Wasmund
Stephen L
SL
Smith
Michael L
ML
Page
Richard L
RL
Joglar
Jose A
JA
Hamdan
Mohamed H
MH
D017704:Baroreflex; D002304:Cardiac Pacing, Artificial; D015331:Cohort Studies; D006439:Hemodynamics; D006801:Humans; D013564:Sympathetic Nervous System / Q000503:physiopathology*; D013610:Tachycardia / Q000503:physiopathology* / Q000628:therapy*