TY - JOUR
T1 - Sympathetic nerve activity and simulated diving in healthy humans
AU - Shamsuzzaman, Abu
AU - Ackerman, Michael J.
AU - Kuniyoshi, Fatima Sert
AU - Accurso, Valentina
AU - Davison, Diane
AU - Amin, Raouf S.
AU - Somers, Virend K.
N1 - Funding Information:
These studies were supported by a Perkins Memorial Award , an American Heart Association Scientist Development Grant ( 0730129N , AS) and AHA Fellowship Grant ( 09-20069G , FSK), and by the National Institutes of Health (NIH) grants HL-70302 , HL-65176 , TW05463 , TW05469 , and 1 UL1 RR024150 . This publication was made possible by CTSA grant number UL1 TR000135 from the National Center for Advancing Translational Sciences (NCATS) , a component of the NIH. Its contents are solely the responsibility of the authors and do not necessarily represent the official view of NIH.
Funding Information:
Dr. Somers has served as a consultant for Cardiac Concepts, Sepracor, Boston Scientific, and ResMed and is an investigator on studies funded with grants from the Respironics Sleep and Breathing Foundation, Sorin, Inc., and Select Research. None of these companies were involved in this study. Dr. Ackerman is a consultant for Boston Scientific, Gilead Sciences, Medtronic, and St. Jude Medical and receives royalties from Transgenomic for FAMILION-LQTS and FAMILION-CPVT genetic tests. None of these companies were involved in this study. Other authors have no disclosures.
PY - 2014
Y1 - 2014
N2 - The goal of our study was to develop a simple and practical method for simulating diving in humans using facial cold exposure and apnea stimuli to measure neural and circulatory responses during the stimulated diving reflex. We hypothesized that responses to simultaneous facial cold exposure and apnea (simulated diving) would be synergistic, exceeding the sum of responses to individual stimuli. We studied 56 volunteers (24 female and 32 male), average age of 39. years. All subjects were healthy, free of cardiovascular and other diseases, and on no medications. Although muscle sympathetic nerve activity (MSNA), blood pressure, and vascular resistance increased markedly during both early and late phases of simulated diving, significant reductions in heart rate were observed only during the late phase. Total MSNA during simulated diving was greater than combined MSNA responses to the individual stimuli. We found that simulated diving is a powerful stimulus to sympathetic nerve traffic with significant bradycardia evident in the late phase of diving and eliciting synergistic sympathetic and parasympathetic responses. Our data provide insight into autonomic triggers that could help explain catastrophic cardiovascular events that may occur during asphyxia or swimming, such as in patients with obstructive sleep apnea or congenital long QT syndrome.
AB - The goal of our study was to develop a simple and practical method for simulating diving in humans using facial cold exposure and apnea stimuli to measure neural and circulatory responses during the stimulated diving reflex. We hypothesized that responses to simultaneous facial cold exposure and apnea (simulated diving) would be synergistic, exceeding the sum of responses to individual stimuli. We studied 56 volunteers (24 female and 32 male), average age of 39. years. All subjects were healthy, free of cardiovascular and other diseases, and on no medications. Although muscle sympathetic nerve activity (MSNA), blood pressure, and vascular resistance increased markedly during both early and late phases of simulated diving, significant reductions in heart rate were observed only during the late phase. Total MSNA during simulated diving was greater than combined MSNA responses to the individual stimuli. We found that simulated diving is a powerful stimulus to sympathetic nerve traffic with significant bradycardia evident in the late phase of diving and eliciting synergistic sympathetic and parasympathetic responses. Our data provide insight into autonomic triggers that could help explain catastrophic cardiovascular events that may occur during asphyxia or swimming, such as in patients with obstructive sleep apnea or congenital long QT syndrome.
KW - Arrhythmias
KW - Bradycardia
KW - Diving
KW - Long QT syndrome
KW - Microneurography
KW - Sympathetic nervous system
UR - http://www.scopus.com/inward/record.url?scp=84893927586&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84893927586&partnerID=8YFLogxK
U2 - 10.1016/j.autneu.2013.12.001
DO - 10.1016/j.autneu.2013.12.001
M3 - Article
C2 - 24368150
AN - SCOPUS:84893927586
SN - 1566-0702
VL - 181
SP - 74
EP - 78
JO - Autonomic Neuroscience: Basic and Clinical
JF - Autonomic Neuroscience: Basic and Clinical
IS - 1
ER -