A Comparative Study of Vagal Maneuver with Use of the Heart Rate Variability

Seo, Sang Won; Cho, Byung Jun; Kim, Ki Seong; Kim, Jin Woo; Lee, Jang Young; Yang, Hee Bum; Hong, Sung Youp

Abstract

PURPOSE: Aim of this study was to compare the effects of the Valsalva maneuver (VM), carotid sinus massage (CSM) and cold water facial immersion (CWFI) on the automomic nervous system of the heart by measuring heart rate variability.
METHODS
Maximal endurance VM, CSM for 10 seconds, and CWFI for 30 seconds were done on healthy subjects. Prolongation of the R-R interval (RRI), vagal ratio (ratio of maximal RRI after vagal stimulation to mean RRI before stimulation), duration of maximal RRI, and variables from a power spectrum analysis and time domain analysis were compared.
RESULTS
RRIs were significantly prolonged in the CSM and CWFI groups compared to the VM group. Vagal ratio was greatest with the CWFI group. The CSM group had the fastest reaction, with no right and left difference, and the VM group was the slowest. Increase in the high frequency (HF) power of RRI variability was greater with CWFI than with VM. LF/HF ratio showed meaningful decrease with CWFI and CSM as compared to VM. Standard deviation of all normal-to-normal intervals (SDNN) and Square root of the mean of the sum of the squares of differences between adjacent normal-to-normal intervals (RMSSD) was significantly greater with CWFI and with VM than with both CSMs.
CONCLUSION
CWFI could prolongate RRI more than other procedures and could also increase vagal activity of the heart more than other methods. VM is difficult to perform properly, and CSM is prone to complication when done by non-medical personnels. CWFI, however, is a relatively safe technique for primary treatment that can be done with paroxysmal supraventricular tachycardia.