Exercise-induced brachial artery blood flow and vascular function is impaired in systemic sclerosis.
Am J Physiol Heart Circ Physiol
; 311(6): H1375-H1381, 2016 12 01.
Article
in En
| MEDLINE
| ID: mdl-27694218
ABSTRACT
Systemic sclerosis (SSc) is a rare autoimmune disease characterized by debilitating fibrosis and vascular dysfunction; however, little is known about the circulatory response to exercise in this population. Therefore, we examined the peripheral hemodynamic and vasodilatory responses to handgrip exercise in 10 patients with SSc (61 ± 4 yr) and 15 age-matched healthy controls (56 ± 5 yr). Brachial artery diameter, blood flow, and mean arterial pressure (MAP) were determined at rest and during progressive static-intermittent handgrip exercise. Patients with SSc and controls were similar in body stature, handgrip strength, and MAP; however, brachial artery blood flow at rest was nearly twofold lower in patients with SSc compared with controls (22 ± 4 vs. 42 ± 5 ml/min, respectively; P < 0.05). Additionally, SSc patients had an â¼18% smaller brachial artery lumen diameter with an â¼28% thicker arterial wall at rest (P < 0.05). Although, during handgrip exercise, there were no differences in MAP between the groups, exercise-induced hyperemia and therefore vascular conductance were â¼35% lower at all exercise workloads in patients with SSc (P < 0.05). Brachial artery vasodilation, as assessed by the relationship between Δbrachial artery diameter and Δshear rate, was significantly attenuated in the patients with SSc (P < 0.05). Finally, vascular dysfunction in the patients with SSc was accompanied by elevated blood markers of oxidative stress and attenuated endogenous antioxidant activity (P < 0.05). Together, these findings reveal attenuated exercise-induced brachial artery blood flow and conduit arterial vasodilatory dysfunction during handgrip exercise in SSc and suggest that elevated oxidative stress may play a role.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Scleroderma, Systemic
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Vasodilation
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Brachial Artery
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Exercise
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Oxidative Stress
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Hand Strength
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Hyperemia
Type of study:
Observational_studies
Limits:
Female
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Humans
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Male
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Middle aged
Language:
En
Journal:
Am J Physiol Heart Circ Physiol
Journal subject:
CARDIOLOGIA
/
FISIOLOGIA
Year:
2016
Type:
Article