TY - JOUR
T1 - Partial angiotension-converting enzyme inhibition during acute orthostatic stress in persons with tetraplegia
AU - Wecht, Jill M.
AU - Radulovic, Miroslav
AU - Weir, Joseph P.
AU - Lessey, Joanah
AU - Spungen, Ann M.
AU - Bauman, William A.
PY - 2005
Y1 - 2005
N2 - Introduction: Individuals with tetraplegia rely on the renin-angiotensin system for orthostatic blood pressure control. Objectives: To determine the effect of partial angiotensin-converting enzyme (ACE) inhibition on heart rate (HR), active plasma renin (PR), and mean arterial blood pressure (MAP) during acute orthostasis in subjects with tetraplegia (n = 7) and nondisabled persons (n = 8). Methods: Subjects were instructed to avoid caffeine and alcohol for 24 hours before testing and to report to the laboratory between 10 AM and 1 PM. Progressive head-up tilt (15°, 25°, 35°, and 45°) was performed on 2 separate days; Day 1: without ACE inhibition; Day 2: after intravenous (IV) infusion of enalaprilat (0.625 mg). Results: HR was reduced during orthostasis in the tetraplegia compared with the nondisabled group (P < 0.0001), and was unaffected by ACE inhibition in either group. PR was not increased with orthostasis in either group, but was increased after ACE inhibition in both groups (P < 0.001). MAP was not affected by orthostasis in either group, but was reduced with ACE inhibition in both groups (P < 0.01). In the tetraplegia group, MAP was initially reduced after ACE inhibition, but was maintained thereafter with increasing angles of tilt, and no subject complained of symptomatic orthostatic hypotension. Conclusion: Subjects with tetraplegia were tolerant of an acute bout of orthostatic stress after partial ACE inhibition. This may have clinical relevance because of the increased prevalence of type 2 diabetes mellitus in this population and the use of ACE inhibitors for the treatment of progressive renal and cardiovascular disease.
AB - Introduction: Individuals with tetraplegia rely on the renin-angiotensin system for orthostatic blood pressure control. Objectives: To determine the effect of partial angiotensin-converting enzyme (ACE) inhibition on heart rate (HR), active plasma renin (PR), and mean arterial blood pressure (MAP) during acute orthostasis in subjects with tetraplegia (n = 7) and nondisabled persons (n = 8). Methods: Subjects were instructed to avoid caffeine and alcohol for 24 hours before testing and to report to the laboratory between 10 AM and 1 PM. Progressive head-up tilt (15°, 25°, 35°, and 45°) was performed on 2 separate days; Day 1: without ACE inhibition; Day 2: after intravenous (IV) infusion of enalaprilat (0.625 mg). Results: HR was reduced during orthostasis in the tetraplegia compared with the nondisabled group (P < 0.0001), and was unaffected by ACE inhibition in either group. PR was not increased with orthostasis in either group, but was increased after ACE inhibition in both groups (P < 0.001). MAP was not affected by orthostasis in either group, but was reduced with ACE inhibition in both groups (P < 0.01). In the tetraplegia group, MAP was initially reduced after ACE inhibition, but was maintained thereafter with increasing angles of tilt, and no subject complained of symptomatic orthostatic hypotension. Conclusion: Subjects with tetraplegia were tolerant of an acute bout of orthostatic stress after partial ACE inhibition. This may have clinical relevance because of the increased prevalence of type 2 diabetes mellitus in this population and the use of ACE inhibitors for the treatment of progressive renal and cardiovascular disease.
KW - ACE inhibitors
KW - Blood pressure regulation
KW - Orthostasis veterans
KW - Spinal cord injuries
KW - Tetraplegia
UR - http://www.scopus.com/inward/record.url?scp=20844453070&partnerID=8YFLogxK
U2 - 10.1080/10790268.2005.11753806
DO - 10.1080/10790268.2005.11753806
M3 - Article
C2 - 15889697
AN - SCOPUS:20844453070
SN - 1079-0268
VL - 28
SP - 103
EP - 108
JO - Journal of Spinal Cord Medicine
JF - Journal of Spinal Cord Medicine
IS - 2
ER -