['In heart failure (HF) patients, muscle sympathetic nerve activity is increased, and HF patients with the greatest sympathetic activation have the poorest prognosis. In animals, acupuncture is sympathoinhibitory, and the most profound sympathoinhibition occurs in animals with the highest resting sympathetic nerve activity. The purpose of this study was to test the hypothesis that acupuncture is sympathoinhibitory in humans with HF.', 'Fifteen advanced HF patients underwent acute mental stress testing before and during (1) "real" acupuncture (n = 10), (2) non-acupoint acupuncture (n = 10), and (3) no-needle acupuncture control (n = 10). Muscle sympathetic nerve activity (MSNA) was recorded using peroneal microneurography. Resting MSNA was not different before and after acupuncture (52 +/- 22 versus 50 +/- 21 bursts/min, P = NS). During mental stress, SNA increased significantly. This increase was eliminated following real acupuncture (mean delta MSNA pre-acupuncture versus post-acupuncture: 149 +/- 171 versus -169 +/- 130, P =.03), but not after non-acupoint or no-needle acupuncture controls. The changes in blood pressure and heart rate during mental stress were not attenuated by real or control acupuncture.'] Does acupuncture inhibit sympathetic activation during mental stress in advanced heart failure patients?